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st-kitty-graphics-20251230-0.9.3.diff (262745B)

---

 From 16663a03b6d7522d171b9717151040f9fad67f9f Mon Sep 17 00:00:00 2001
 From: Sergei Grechanik <sergei.grechanik@gmail.com>
 Date: Sat, 10 Jan 2026 16:09:05 -0800
 Subject: [PATCH] Kitty graphics protocol support eb8d6cb 2025-12-30
 
 This patch implements the kitty graphics protocol in st.
 See https://github.com/sergei-grechanik/st-graphics
 Created by squashing the graphics branch, the most recent
 commit is eb8d6cbc964a864e6391c4288aebe4ebe74bb5c7 (2025-12-30).
 
 Squashed on top of 6e970474743d57a5d8b054c41fd3bff2bc895742 (0.9.3)
 
 Note that the following files were excluded from the squash:
   .clang-format
   README.md
   generate-rowcolumn-helpers.py
   rowcolumn-diacritics.txt
   rowcolumn_diacritics.sh
 
 Main changes since 2025-02-22:
   * Restore evicted images from original files when available.
   * Fix an issue that caused too many files to be opened during
     concurrent direct uploads.
   * Optimize scaled pixmap generation (don't store pad pixels; upscale
     with XRender).
 
 Main changes since 2024-09-22:
   * Restore text under classic placements on deletion.
   * Support uploading via shared memory (t=s).
   * Bug fixes.
 ---
  Makefile                       |    7 +-
  config.def.h                   |   46 +-
  config.mk                      |    5 +-
  graphics.c                     | 4393 ++++++++++++++++++++++++++++++++
  graphics.h                     |  112 +
  icat-mini.sh                   |  875 +++++++
  khash.h                        |  627 +++++
  kvec.h                         |   90 +
  rowcolumn_diacritics_helpers.c |  391 +++
  st.c                           |  303 ++-
  st.h                           |   84 +-
  st.info                        |    6 +
  win.h                          |    3 +
  x.c                            |  411 ++-
  14 files changed, 7295 insertions(+), 58 deletions(-)
  create mode 100644 graphics.c
  create mode 100644 graphics.h
  create mode 100755 icat-mini.sh
  create mode 100644 khash.h
  create mode 100644 kvec.h
  create mode 100644 rowcolumn_diacritics_helpers.c
 
 diff --git a/Makefile b/Makefile
 index 15db421..413e7ab 100644
 --- a/Makefile
 +++ b/Makefile
 @@ -4,7 +4,7 @@
  
  include config.mk
  
 -SRC = st.c x.c
 +SRC = st.c x.c rowcolumn_diacritics_helpers.c graphics.c
  OBJ = $(SRC:.c=.o)
  
  all: st
 @@ -15,8 +15,9 @@ config.h:
  .c.o:
  	$(CC) $(STCFLAGS) -c $<
  
 -st.o: config.h st.h win.h
 -x.o: arg.h config.h st.h win.h
 +st.o: config.h st.h win.h graphics.h
 +x.o: arg.h config.h st.h win.h graphics.h
 +graphics.c: graphics.h khash.h kvec.h st.h
  
  $(OBJ): config.h config.mk
  
 diff --git a/config.def.h b/config.def.h
 index 2cd740a..4aadbbc 100644
 --- a/config.def.h
 +++ b/config.def.h
 @@ -8,6 +8,13 @@
  static char *font = "Liberation Mono:pixelsize=12:antialias=true:autohint=true";
  static int borderpx = 2;
  
 +/* How to align the content in the window when the size of the terminal
 + * doesn't perfectly match the size of the window. The values are percentages.
 + * 50 means center, 0 means flush left/top, 100 means flush right/bottom.
 + */
 +static int anysize_halign = 50;
 +static int anysize_valign = 50;
 +
  /*
   * What program is execed by st depends of these precedence rules:
   * 1: program passed with -e
 @@ -23,7 +30,8 @@ char *scroll = NULL;
  char *stty_args = "stty raw pass8 nl -echo -iexten -cstopb 38400";
  
  /* identification sequence returned in DA and DECID */
 -char *vtiden = "\033[?6c";
 +/* By default, use the same one as kitty. */
 +char *vtiden = "\033[?62c";
  
  /* Kerning / character bounding-box multipliers */
  static float cwscale = 1.0;
 @@ -163,6 +171,28 @@ static unsigned int mousebg = 0;
   */
  static unsigned int defaultattr = 11;
  
 +/*
 + * Graphics configuration
 + */
 +
 +/// The template for the cache directory.
 +const char graphics_cache_dir_template[] = "/tmp/st-images-XXXXXX";
 +/// The max size of a single image file, in bytes.
 +unsigned graphics_max_single_image_file_size = 20 * 1024 * 1024;
 +/// The max size of the cache, in bytes.
 +unsigned graphics_total_file_cache_size = 300 * 1024 * 1024;
 +/// The max ram size of an image or placement, in bytes.
 +unsigned graphics_max_single_image_ram_size = 100 * 1024 * 1024;
 +/// The max total size of all images loaded into RAM.
 +unsigned graphics_max_total_ram_size = 300 * 1024 * 1024;
 +/// The max total number of image placements and images.
 +unsigned graphics_max_total_placements = 4096;
 +/// The ratio by which limits can be exceeded. This is to reduce the frequency
 +/// of image removal.
 +double graphics_excess_tolerance_ratio = 0.05;
 +/// The minimum delay between redraws caused by animations, in milliseconds.
 +unsigned graphics_animation_min_delay = 20;
 +
  /*
   * Force mouse select/shortcuts while mask is active (when MODE_MOUSE is set).
   * Note that if you want to use ShiftMask with selmasks, set this to an other
 @@ -170,12 +200,18 @@ static unsigned int defaultattr = 11;
   */
  static uint forcemousemod = ShiftMask;
  
 +/* Internal keyboard shortcuts. */
 +#define MODKEY Mod1Mask
 +#define TERMMOD (ControlMask|ShiftMask)
 +
  /*
   * Internal mouse shortcuts.
   * Beware that overloading Button1 will disable the selection.
   */
  static MouseShortcut mshortcuts[] = {
  	/* mask                 button   function        argument       release */
 +	{ TERMMOD,              Button3, previewimage,   {.s = "feh"} },
 +	{ TERMMOD,              Button2, showimageinfo,  {},            1 },
  	{ XK_ANY_MOD,           Button2, selpaste,       {.i = 0},      1 },
  	{ ShiftMask,            Button4, ttysend,        {.s = "\033[5;2~"} },
  	{ XK_ANY_MOD,           Button4, ttysend,        {.s = "\031"} },
 @@ -183,10 +219,6 @@ static MouseShortcut mshortcuts[] = {
  	{ XK_ANY_MOD,           Button5, ttysend,        {.s = "\005"} },
  };
  
 -/* Internal keyboard shortcuts. */
 -#define MODKEY Mod1Mask
 -#define TERMMOD (ControlMask|ShiftMask)
 -
  static Shortcut shortcuts[] = {
  	/* mask                 keysym          function        argument */
  	{ XK_ANY_MOD,           XK_Break,       sendbreak,      {.i =  0} },
 @@ -201,6 +233,10 @@ static Shortcut shortcuts[] = {
  	{ TERMMOD,              XK_Y,           selpaste,       {.i =  0} },
  	{ ShiftMask,            XK_Insert,      selpaste,       {.i =  0} },
  	{ TERMMOD,              XK_Num_Lock,    numlock,        {.i =  0} },
 +	{ TERMMOD,              XK_F1,          togglegrdebug,  {.i =  0} },
 +	{ TERMMOD,              XK_F6,          dumpgrstate,    {.i =  0} },
 +	{ TERMMOD,              XK_F7,          unloadimages,   {.i =  0} },
 +	{ TERMMOD,              XK_F8,          toggleimages,   {.i =  0} },
  };
  
  /*
 diff --git a/config.mk b/config.mk
 index 2fc854e..7b22243 100644
 --- a/config.mk
 +++ b/config.mk
 @@ -14,9 +14,12 @@ PKG_CONFIG = pkg-config
  
  # includes and libs
  INCS = -I$(X11INC) \
 +       `$(PKG_CONFIG) --cflags imlib2` \
         `$(PKG_CONFIG) --cflags fontconfig` \
         `$(PKG_CONFIG) --cflags freetype2`
 -LIBS = -L$(X11LIB) -lm -lrt -lX11 -lutil -lXft \
 +LIBS = -L$(X11LIB) -lm -lrt -lX11 -lutil -lXft -lXrender \
 +       `$(PKG_CONFIG) --libs imlib2` \
 +       `$(PKG_CONFIG) --libs zlib` \
         `$(PKG_CONFIG) --libs fontconfig` \
         `$(PKG_CONFIG) --libs freetype2`
  
 diff --git a/graphics.c b/graphics.c
 new file mode 100644
 index 0000000..801f5c9
 --- /dev/null
 +++ b/graphics.c
 @@ -0,0 +1,4393 @@
 +/* The MIT License
 +
 +   Copyright (c) 2021-2024 Sergei Grechanik <sergei.grechanik@gmail.com>
 +
 +   Permission is hereby granted, free of charge, to any person obtaining
 +   a copy of this software and associated documentation files (the
 +   "Software"), to deal in the Software without restriction, including
 +   without limitation the rights to use, copy, modify, merge, publish,
 +   distribute, sublicense, and/or sell copies of the Software, and to
 +   permit persons to whom the Software is furnished to do so, subject to
 +   the following conditions:
 +
 +   The above copyright notice and this permission notice shall be
 +   included in all copies or substantial portions of the Software.
 +
 +   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 +   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 +   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 +   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 +   BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 +   ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 +   CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 +   SOFTWARE.
 +*/
 +
 +////////////////////////////////////////////////////////////////////////////////
 +//
 +// This file implements a subset of the kitty graphics protocol.
 +//
 +////////////////////////////////////////////////////////////////////////////////
 +
 +// A workaround for mac os to enable mkdtemp.
 +#ifdef __APPLE__
 +#define _DARWIN_C_SOURCE
 +#endif
 +
 +#define _POSIX_C_SOURCE 200809L
 +
 +#include <zlib.h>
 +#include <Imlib2.h>
 +#include <X11/Xlib.h>
 +#include <X11/extensions/Xrender.h>
 +
 +#include <assert.h>
 +#include <ctype.h>
 +#include <errno.h>
 +#include <fcntl.h>
 +#include <math.h>
 +#include <spawn.h>
 +#include <stdarg.h>
 +#include <stdio.h>
 +#include <stdlib.h>
 +#include <string.h>
 +#include <sys/mman.h>
 +#include <sys/stat.h>
 +#include <time.h>
 +#include <unistd.h>
 +
 +#include "khash.h"
 +#include "kvec.h"
 +
 +#include "st.h"
 +#include "graphics.h"
 +
 +extern char **environ;
 +
 +#define MAX_FILENAME_SIZE 256
 +#define MAX_INFO_LEN 256
 +#define MAX_IMAGE_RECTS 20
 +
 +/// The type used in this file to represent time. Used both for time differences
 +/// and absolute times (as milliseconds since an arbitrary point in time, see
 +/// `initialization_time`).
 +typedef int64_t Milliseconds;
 +
 +enum ScaleMode {
 +	SCALE_MODE_UNSET = 0,
 +	/// Stretch or shrink the image to fill the box, ignoring aspect ratio.
 +	SCALE_MODE_FILL = 1,
 +	/// Preserve aspect ratio and fit to width or to height so that the
 +	/// whole image is visible.
 +	SCALE_MODE_CONTAIN = 2,
 +	/// Do not scale. The image may be cropped if the box is too small.
 +	SCALE_MODE_NONE = 3,
 +	/// Do not scale, unless the box is too small, in which case the image
 +	/// will be shrunk like with `SCALE_MODE_CONTAIN`.
 +	SCALE_MODE_NONE_OR_CONTAIN = 4,
 +};
 +
 +enum AnimationState {
 +	ANIMATION_STATE_UNSET = 0,
 +	/// The animation is stopped. Display the current frame, but don't
 +	/// advance to the next one.
 +	ANIMATION_STATE_STOPPED = 1,
 +	/// Run the animation to then end, then wait for the next frame.
 +	ANIMATION_STATE_LOADING = 2,
 +	/// Run the animation in a loop.
 +	ANIMATION_STATE_LOOPING = 3,
 +};
 +
 +/// The status of an image. Each image uploaded to the terminal is cached on
 +/// disk, then it is loaded to ram when needed.
 +enum ImageStatus {
 +	STATUS_UNINITIALIZED = 0,
 +	STATUS_UPLOADING = 1,
 +	STATUS_UPLOADING_ERROR = 2,
 +	STATUS_UPLOADING_SUCCESS = 3,
 +	STATUS_RAM_LOADING_ERROR = 4,
 +	STATUS_RAM_LOADING_SUCCESS = 6,
 +};
 +
 +const char *image_status_strings[6] = {
 +	"STATUS_UNINITIALIZED",
 +	"STATUS_UPLOADING",
 +	"STATUS_UPLOADING_ERROR",
 +	"STATUS_UPLOADING_SUCCESS",
 +	"STATUS_RAM_LOADING_ERROR",
 +	"STATUS_RAM_LOADING_SUCCESS",
 +};
 +
 +enum ImageUploadingFailure {
 +	ERROR_OVER_SIZE_LIMIT = 1,
 +	ERROR_CANNOT_OPEN_CACHED_FILE = 2,
 +	ERROR_UNEXPECTED_SIZE = 3,
 +	ERROR_CANNOT_COPY_FILE = 4,
 +	ERROR_CANNOT_OPEN_SHM = 5,
 +	ERROR_MTIME_MISMATCH = 3,
 +};
 +
 +const char *image_uploading_failure_strings[7] = {
 +	"NO_ERROR",
 +	"ERROR_OVER_SIZE_LIMIT",
 +	"ERROR_CANNOT_OPEN_CACHED_FILE",
 +	"ERROR_UNEXPECTED_SIZE",
 +	"ERROR_CANNOT_COPY_FILE",
 +	"ERROR_CANNOT_OPEN_SHM",
 +	"ERROR_MTIME_MISMATCH",
 +};
 +
 +////////////////////////////////////////////////////////////////////////////////
 +//
 +// We use the following structures to represent images and placements:
 +//
 +//   - Image: this is the main structure representing an image, usually created
 +//     by actions 'a=t', 'a=T`. Each image has an id (image id aka client id,
 +//     specified by 'i='). An image may have multiple frames (ImageFrame) and
 +//     placements (ImagePlacement).
 +//
 +//   - ImageFrame: represents a single frame of an image, usually created by
 +//     the action 'a=f' (and the first frame is created with the image itself).
 +//     Each frame has an index and also:
 +//     - a file containing the frame data (considered to be "on disk", although
 +//       it's probably in tmpfs),
 +//     - an imlib object containing the fully composed frame (i.e. the frame
 +//       data from the file composed onto the background frame or color). It is
 +//       not ready for display yet, because it needs to be scaled and uploaded
 +//       to the X server.
 +//
 +//   - ImagePlacement: represents a placement of an image, created by 'a=p' and
 +//     'a=T'. Each placement has an id (placement id, specified by 'p='). Also
 +//     each placement has an array of pixmaps: one for each frame of the image.
 +//     Each pixmap is a scaled and uploaded image ready to be displayed.
 +//
 +// Images are store in the `images` hash table, mapping image ids to Image
 +// objects (allocated on the heap).
 +//
 +// Placements are stored in the `placements` hash table of each Image object,
 +// mapping placement ids to ImagePlacement objects (also allocated on the heap).
 +//
 +// ImageFrames are stored in the `first_frame` field and in the
 +// `frames_beyond_the_first` array of each Image object. They are stored by
 +// value, so ImageFrame pointer may be invalidated when frames are
 +// added/deleted, be careful.
 +//
 +////////////////////////////////////////////////////////////////////////////////
 +
 +struct Image;
 +struct ImageFrame;
 +struct ImagePlacement;
 +
 +KHASH_MAP_INIT_INT(id2image, struct Image *)
 +KHASH_MAP_INIT_INT(id2placement, struct ImagePlacement *)
 +
 +/// A transformation to apply to a pixmap before drawing it.
 +typedef struct PixmapTransformation {
 +	/// The width and height of the pixmap.
 +	int pixmap_w, pixmap_h;
 +	/// The width and height of the transformed pixmap.
 +	int dst_w, dst_h;
 +	/// The offset relative to the top-left corner of the box of cells where
 +	/// the transformed pixmap is drawn.
 +	int dst_x, dst_y;
 +} PixmapTransformation;
 +
 +typedef struct ImageFrame {
 +	/// The image this frame belongs to.
 +	struct Image *image;
 +	/// The 1-based index of the frame. Zero if the frame isn't initialized.
 +	int index;
 +	/// The last time when the frame was displayed or otherwise touched.
 +	Milliseconds atime;
 +	/// The background color of the frame in the 0xRRGGBBAA format.
 +	uint32_t background_color;
 +	/// The index of the background frame. Zero to use the color instead.
 +	int background_frame_index;
 +	/// The duration of the frame in milliseconds.
 +	int gap;
 +	/// The expected size of the frame image file (specified with 'S='),
 +	/// used to check if uploading succeeded.
 +	unsigned expected_size;
 +	/// Format specification (see the `f=` key).
 +	int format;
 +	/// Pixel width and height of the non-composed (on-disk) frame data. May
 +	/// differ from the image (i.e. first frame) dimensions.
 +	int data_pix_width, data_pix_height;
 +	/// The offset of the frame relative to the first frame.
 +	int x, y;
 +	/// Compression mode (see the `o=` key).
 +	char compression;
 +	/// The status (see `ImageStatus`).
 +	char status;
 +	/// Whether loading into ram is in progress. This is used to avoid
 +	/// cyclic dependencies between frames.
 +	char ram_loading_in_progress;
 +	/// The reason of uploading failure (see `ImageUploadingFailure`).
 +	char uploading_failure;
 +	/// Whether failures and successes should be reported ('q=').
 +	char quiet;
 +	/// Whether to blend the frame with the background or replace it.
 +	char blend;
 +	/// The original file name used with file transmission. Malloced.
 +	char *original_filename;
 +	/// The modification time of the original file used with file
 +	/// transmission.
 +	time_t original_file_mtime;
 +	/// The file corresponding to the on-disk cache, used when uploading.
 +	FILE *open_file;
 +	/// The size of the corresponding file cached on disk.
 +	unsigned disk_size;
 +	/// The imlib object containing the fully composed frame. It's not
 +	/// scaled for screen display yet.
 +	Imlib_Image imlib_object;
 +} ImageFrame;
 +
 +typedef struct Image {
 +	/// The client id (the one specified with 'i='). Must be nonzero.
 +	uint32_t image_id;
 +	/// The client id specified in the query command (`a=q`). This one must
 +	/// be used to create the response if it's non-zero.
 +	uint32_t query_id;
 +	/// The number specified in the transmission command (`I=`). If
 +	/// non-zero, it may be used to identify the image instead of the
 +	/// image_id, and it also should be mentioned in responses.
 +	uint32_t image_number;
 +	/// The last time when the image was displayed or otherwise touched.
 +	Milliseconds atime;
 +	/// The total duration of the animation in milliseconds.
 +	int total_duration;
 +	/// The total size of cached image files for all frames.
 +	int total_disk_size;
 +	/// The global index of the creation command. Used to decide which image
 +	/// is newer if they have the same image number.
 +	uint64_t global_command_index;
 +	/// The 1-based index of the currently displayed frame.
 +	int current_frame;
 +	/// The state of the animation, see `AnimationState`.
 +	char animation_state;
 +	/// The absolute time that is assumed to be the start of the current
 +	/// frame (in ms since initialization).
 +	Milliseconds current_frame_time;
 +	/// The absolute time of the last redraw (in ms since initialization).
 +	/// Used to check whether it's the first time we draw the image in the
 +	/// current redraw cycle.
 +	Milliseconds last_redraw;
 +	/// The absolute time of the next redraw (in ms since initialization).
 +	/// 0 means no redraw is scheduled.
 +	Milliseconds next_redraw;
 +	/// The unscaled pixel width and height of the image. Usually inherited
 +	/// from the first frame.
 +	int pix_width, pix_height;
 +	/// The first frame.
 +	ImageFrame first_frame;
 +	/// The array of frames beyond the first one.
 +	kvec_t(ImageFrame) frames_beyond_the_first;
 +	/// Image placements.
 +	khash_t(id2placement) *placements;
 +	/// The default placement.
 +	uint32_t default_placement;
 +	/// The initial placement id, specified with the transmission command,
 +	/// used to report success or failure.
 +	uint32_t initial_placement_id;
 +} Image;
 +
 +typedef struct ImagePlacement {
 +	/// The image this placement belongs to.
 +	Image *image;
 +	/// The id of the placement. Must be nonzero.
 +	uint32_t placement_id;
 +	/// The last time when the placement was displayed or otherwise touched.
 +	Milliseconds atime;
 +	/// The 1-based index of the protected pixmap. We protect a pixmap in
 +	/// gr_load_pixmap to avoid unloading it right after it was loaded.
 +	int protected_frame;
 +	/// Whether the placement is used only for Unicode placeholders.
 +	char virtual;
 +	/// The scaling mode (see `ScaleMode`).
 +	char scale_mode;
 +	/// Height and width in cells.
 +	uint16_t rows, cols;
 +	/// Top-left corner of the source rectangle ('x=' and 'y=').
 +	int src_pix_x, src_pix_y;
 +	/// Height and width of the source rectangle (zero if full image).
 +	int src_pix_width, src_pix_height;
 +	/// The image appropriately scaled and uploaded to the X server. This
 +	/// pixmap is premultiplied by alpha.
 +	Pixmap first_pixmap;
 +	/// The array of pixmaps beyond the first one.
 +	kvec_t(Pixmap) pixmaps_beyond_the_first;
 +	/// The dimensions of the cell used to scale the image. If cell
 +	/// dimensions are changed (font change), the image will be rescaled.
 +	uint16_t scaled_cw, scaled_ch;
 +	/// The transformation to apply to the pixmap before drawing it.
 +	PixmapTransformation pixmap_transformation;
 +	/// If true, do not move the cursor when displaying this placement
 +	/// (non-virtual placements only).
 +	char do_not_move_cursor;
 +	/// The text underneath this placement, valid only for classic
 +	/// placements. On deletion, the text is restored. This is a malloced
 +	/// array of rows*cols Glyphs.
 +	Glyph *text_underneath;
 +} ImagePlacement;
 +
 +/// A rectangular piece of an image to be drawn.
 +typedef struct {
 +	uint32_t image_id;
 +	uint32_t placement_id;
 +	/// The position of the rectangle in pixels.
 +	int screen_x_pix, screen_y_pix;
 +	/// The starting row on the screen.
 +	int screen_y_row;
 +	/// The part of the whole image to be drawn, in cells. Starts are
 +	/// zero-based, ends are exclusive.
 +	int img_start_col, img_end_col, img_start_row, img_end_row;
 +	/// The current cell width and height in pixels.
 +	int cw, ch;
 +	/// Whether colors should be inverted.
 +	int reverse;
 +} ImageRect;
 +
 +/// Executes `code` for each frame of an image. Example:
 +///
 +///     foreach_frame(image, frame, {
 +///         printf("Frame %d\n", frame->index);
 +///     });
 +///
 +#define foreach_frame(image, framevar, code) { size_t __i; \
 +	for (__i = 0; __i <= kv_size((image).frames_beyond_the_first); ++__i) { \
 +		ImageFrame *framevar = \
 +			__i == 0 ? &(image).first_frame \
 +			: &kv_A((image).frames_beyond_the_first, __i - 1); \
 +		code; \
 +	} }
 +
 +/// Executes `code` for each pixmap of a placement. Example:
 +///
 +///     foreach_pixmap(placement, pixmap, {
 +///         ...
 +///     });
 +///
 +#define foreach_pixmap(placement, pixmapvar, code) { size_t __i; \
 +	for (__i = 0; __i <= kv_size((placement).pixmaps_beyond_the_first); ++__i) { \
 +		Pixmap pixmapvar = \
 +			__i == 0 ? (placement).first_pixmap \
 +			: kv_A((placement).pixmaps_beyond_the_first, __i - 1); \
 +		code; \
 +	} }
 +
 +
 +static Image *gr_find_image(uint32_t image_id);
 +static void gr_get_frame_filename(ImageFrame *frame, char *out, size_t max_len);
 +static void gr_delete_image(Image *img);
 +static void gr_erase_placement(ImagePlacement *placement);
 +static void gr_check_limits();
 +static void gr_try_restore_imagefile(ImageFrame *frame);
 +static char *gr_base64dec(const char *src, size_t *size);
 +static void sanitize_str(char *str, size_t max_len);
 +static const char *sanitized_filename(const char *str);
 +
 +/// The array of image rectangles to draw. It is reset each frame.
 +static ImageRect image_rects[MAX_IMAGE_RECTS] = {{0}};
 +/// The known images (including the ones being uploaded).
 +static khash_t(id2image) *images = NULL;
 +/// The total number of placements in all images.
 +static unsigned total_placement_count = 0;
 +/// The total size of all image files stored in the on-disk cache.
 +static int64_t images_disk_size = 0;
 +/// The total size of all images and placements loaded into ram.
 +static int64_t images_ram_size = 0;
 +/// The id of the last loaded image.
 +static uint32_t last_image_id = 0;
 +/// Current cell width and heigh in pixels.
 +static int current_cw = 0, current_ch = 0;
 +/// The id of the currently uploaded image (when using direct uploading).
 +static uint32_t current_upload_image_id = 0;
 +/// The index of the frame currently being uploaded.
 +static int current_upload_frame_index = 0;
 +/// The time when the graphics module was initialized.
 +static struct timespec initialization_time = {0};
 +/// The time when the current frame drawing started, used for debugging fps and
 +/// to calculate the current frame for animations.
 +static Milliseconds drawing_start_time;
 +/// The global index of the current command.
 +static uint64_t global_command_counter = 0;
 +/// The next redraw times for each row of the terminal. Used for animations.
 +/// 0 means no redraw is scheduled.
 +static kvec_t(Milliseconds) next_redraw_times = {0, 0, NULL};
 +/// The number of files loaded in the current redraw cycle or command execution.
 +static int debug_loaded_files_counter = 0;
 +/// The number of pixmaps loaded in the current redraw cycle or command execution.
 +static int debug_loaded_pixmaps_counter = 0;
 +
 +/// The directory where the cache files are stored.
 +static char cache_dir[MAX_FILENAME_SIZE - 16];
 +
 +/// The table used for color inversion.
 +static unsigned char reverse_table[256];
 +
 +// Declared in the header.
 +GraphicsDebugMode graphics_debug_mode = GRAPHICS_DEBUG_NONE;
 +char graphics_display_images = 1;
 +GraphicsCommandResult graphics_command_result = {0};
 +int graphics_next_redraw_delay = INT_MAX;
 +
 +// Defined in config.h
 +extern const char graphics_cache_dir_template[];
 +extern unsigned graphics_max_single_image_file_size;
 +extern unsigned graphics_total_file_cache_size;
 +extern unsigned graphics_max_single_image_ram_size;
 +extern unsigned graphics_max_total_ram_size;
 +extern unsigned graphics_max_total_placements;
 +extern double graphics_excess_tolerance_ratio;
 +extern unsigned graphics_animation_min_delay;
 +
 +// Constants that are not important enough to expose in the config.
 +
 +/// The time after which an interrupted (with another command) direct
 +/// transmission cannot be resumed.
 +static Milliseconds graphics_direct_transmission_timeout_ms = 2000;
 +
 +////////////////////////////////////////////////////////////////////////////////
 +// Basic helpers.
 +////////////////////////////////////////////////////////////////////////////////
 +
 +#define MIN(a, b)		((a) < (b) ? (a) : (b))
 +#define MAX(a, b)		((a) < (b) ? (b) : (a))
 +
 +/// Returns the difference between `end` and `start` in milliseconds.
 +static int64_t gr_timediff_ms(const struct timespec *end,
 +			      const struct timespec *start) {
 +	return (end->tv_sec - start->tv_sec) * 1000 +
 +	       (end->tv_nsec - start->tv_nsec) / 1000000;
 +}
 +
 +/// Returns the current time in milliseconds since the initialization.
 +static Milliseconds gr_now_ms() {
 +	struct timespec now;
 +	clock_gettime(CLOCK_MONOTONIC, &now);
 +	return gr_timediff_ms(&now, &initialization_time);
 +}
 +
 +////////////////////////////////////////////////////////////////////////////////
 +// Logging.
 +////////////////////////////////////////////////////////////////////////////////
 +
 +#define GR_LOG(...) \
 +	do { if(graphics_debug_mode) fprintf(stderr, __VA_ARGS__); } while(0)
 +
 +////////////////////////////////////////////////////////////////////////////////
 +// Basic image management functions (create, delete, find, etc).
 +////////////////////////////////////////////////////////////////////////////////
 +
 +/// Returns the 1-based index of the last frame. Note that you may want to use
 +/// `gr_last_uploaded_frame_index` instead since the last frame may be not
 +/// fully uploaded yet.
 +static inline int gr_last_frame_index(Image *img) {
 +	return kv_size(img->frames_beyond_the_first) + 1;
 +}
 +
 +/// Returns the frame with the given index. Returns NULL if the index is out of
 +/// bounds. The index is 1-based.
 +static ImageFrame *gr_get_frame(Image *img, int index) {
 +	if (!img)
 +		return NULL;
 +	if (index == 1)
 +		return &img->first_frame;
 +	if (2 <= index && index <= gr_last_frame_index(img))
 +		return &kv_A(img->frames_beyond_the_first, index - 2);
 +	return NULL;
 +}
 +
 +/// Returns the last frame of the image. Returns NULL if `img` is NULL.
 +static ImageFrame *gr_get_last_frame(Image *img) {
 +	if (!img)
 +		return NULL;
 +	return gr_get_frame(img, gr_last_frame_index(img));
 +}
 +
 +/// Returns the 1-based index of the last frame or the second-to-last frame if
 +/// the last frame is not fully uploaded yet.
 +static inline int gr_last_uploaded_frame_index(Image *img) {
 +	int last_index = gr_last_frame_index(img);
 +	if (last_index > 1 &&
 +	    gr_get_frame(img, last_index)->status < STATUS_UPLOADING_SUCCESS)
 +		return last_index - 1;
 +	return last_index;
 +}
 +
 +/// Returns the pixmap for the frame with the given index. Returns 0 if the
 +/// index is out of bounds. The index is 1-based.
 +static Pixmap gr_get_frame_pixmap(ImagePlacement *placement, int index) {
 +	if (index == 1)
 +		return placement->first_pixmap;
 +	if (2 <= index &&
 +	    index <= kv_size(placement->pixmaps_beyond_the_first) + 1)
 +		return kv_A(placement->pixmaps_beyond_the_first, index - 2);
 +	return 0;
 +}
 +
 +/// Sets the pixmap for the frame with the given index. The index is 1-based.
 +/// The array of pixmaps is resized if needed.
 +static void gr_set_frame_pixmap(ImagePlacement *placement, int index,
 +				Pixmap pixmap) {
 +	if (index == 1) {
 +		placement->first_pixmap = pixmap;
 +		return;
 +	}
 +	// Resize the array if needed.
 +	size_t old_size = kv_size(placement->pixmaps_beyond_the_first);
 +	if (old_size < index - 1) {
 +		kv_a(Pixmap, placement->pixmaps_beyond_the_first, index - 2);
 +		for (size_t i = old_size; i < index - 1; i++)
 +			kv_A(placement->pixmaps_beyond_the_first, i) = 0;
 +	}
 +	kv_A(placement->pixmaps_beyond_the_first, index - 2) = pixmap;
 +}
 +
 +/// Finds the image corresponding to the client id. Returns NULL if cannot find.
 +static Image *gr_find_image(uint32_t image_id) {
 +	khiter_t k = kh_get(id2image, images, image_id);
 +	if (k == kh_end(images))
 +		return NULL;
 +	Image *res = kh_value(images, k);
 +	return res;
 +}
 +
 +/// Finds the newest image corresponding to the image number. Returns NULL if
 +/// cannot find.
 +static Image *gr_find_image_by_number(uint32_t image_number) {
 +	if (image_number == 0)
 +		return NULL;
 +	Image *newest_img = NULL;
 +	Image *img = NULL;
 +	kh_foreach_value(images, img, {
 +		if (img->image_number == image_number &&
 +		    (!newest_img || newest_img->global_command_index <
 +					    img->global_command_index))
 +			newest_img = img;
 +	});
 +	if (!newest_img)
 +		GR_LOG("Image number %u not found\n", image_number);
 +	else
 +		GR_LOG("Found image number %u, its id is %u\n", image_number,
 +		       img->image_id);
 +	return newest_img;
 +}
 +
 +/// Finds the placement corresponding to the id. If the placement id is 0,
 +/// returns some default placement.
 +static ImagePlacement *gr_find_placement(Image *img, uint32_t placement_id) {
 +	if (!img)
 +		return NULL;
 +	if (placement_id == 0) {
 +		// Try to get the default placement.
 +		ImagePlacement *dflt = NULL;
 +		if (img->default_placement != 0)
 +			dflt = gr_find_placement(img, img->default_placement);
 +		if (dflt)
 +			return dflt;
 +		// If there is no default placement, return the first one and
 +		// set it as the default.
 +		kh_foreach_value(img->placements, dflt, {
 +			img->default_placement = dflt->placement_id;
 +			return dflt;
 +		});
 +		// If there are no placements, return NULL.
 +		return NULL;
 +	}
 +	khiter_t k = kh_get(id2placement, img->placements, placement_id);
 +	if (k == kh_end(img->placements))
 +		return NULL;
 +	ImagePlacement *res = kh_value(img->placements, k);
 +	return res;
 +}
 +
 +/// Finds the placement by image id and placement id.
 +static ImagePlacement *gr_find_image_and_placement(uint32_t image_id,
 +						   uint32_t placement_id) {
 +	return gr_find_placement(gr_find_image(image_id), placement_id);
 +}
 +
 +/// Returns a pointer to the glyph under the classic placement with `image_id`
 +/// and `placement_id` at `col` and `row` (1-based). May return NULL if the
 +/// underneath text is unknown.
 +Glyph *gr_get_glyph_underneath_image(uint32_t image_id, uint32_t placement_id,
 +				     int col, int row) {
 +	ImagePlacement *placement =
 +		gr_find_image_and_placement(image_id, placement_id);
 +	if (!placement || !placement->text_underneath)
 +		return NULL;
 +	col--;
 +	row--;
 +	if (col < 0 || col >= placement->cols || row < 0 ||
 +	    row >= placement->rows)
 +		return NULL;
 +	return &placement->text_underneath[row * placement->cols + col];
 +}
 +
 +/// Writes the name of the on-disk cache file to `out`. `max_len` should be the
 +/// size of `out`. The name will be something like
 +/// "/tmp/st-images-xxx/img-ID-FRAME".
 +static void gr_get_frame_filename(ImageFrame *frame, char *out,
 +				  size_t max_len) {
 +	snprintf(out, max_len, "%s/img-%.3u-%.3u", cache_dir,
 +		 frame->image->image_id, frame->index);
 +}
 +
 +/// Returns the (estimation) of the RAM size used by the frame right now.
 +static unsigned gr_frame_current_ram_size(ImageFrame *frame) {
 +	if (!frame->imlib_object)
 +		return 0;
 +	return (unsigned)frame->image->pix_width * frame->image->pix_height * 4;
 +}
 +
 +/// Returns the (estimation) of the RAM size used by a single frame pixmap.
 +static unsigned gr_placement_single_frame_ram_size(ImagePlacement *placement) {
 +	return (unsigned)placement->pixmap_transformation.pixmap_w *
 +	       placement->pixmap_transformation.pixmap_h * 4;
 +}
 +
 +/// Returns the (estimation) of the RAM size used by the placemenet right now.
 +static unsigned gr_placement_current_ram_size(ImagePlacement *placement) {
 +	unsigned single_frame_size =
 +		gr_placement_single_frame_ram_size(placement);
 +	unsigned result = 0;
 +	foreach_pixmap(*placement, pixmap, {
 +		if (pixmap)
 +			result += single_frame_size;
 +	});
 +	return result;
 +}
 +
 +/// Unload the frame from RAM (i.e. delete the corresponding imlib object).
 +/// If the on-disk file of the frame is preserved, it can be reloaded later.
 +static void gr_unload_frame(ImageFrame *frame) {
 +	if (!frame->imlib_object)
 +		return;
 +
 +	unsigned frame_ram_size = gr_frame_current_ram_size(frame);
 +	images_ram_size -= frame_ram_size;
 +
 +	imlib_context_set_image(frame->imlib_object);
 +	imlib_free_image_and_decache();
 +	frame->imlib_object = NULL;
 +
 +	GR_LOG("After unloading image %u frame %u (atime %ld ms ago) "
 +	       "ram: %ld KiB  (- %u KiB)\n",
 +	       frame->image->image_id, frame->index,
 +	       drawing_start_time - frame->atime, images_ram_size / 1024,
 +	       frame_ram_size / 1024);
 +}
 +
 +/// Unload all frames of the image.
 +static void gr_unload_all_frames(Image *img) {
 +	foreach_frame(*img, frame, {
 +		gr_unload_frame(frame);
 +	});
 +}
 +
 +/// Unload the placement from RAM (i.e. free all of the corresponding pixmaps).
 +/// If the on-disk files or imlib objects of the corresponding image are
 +/// preserved, the placement can be reloaded later.
 +static void gr_unload_placement(ImagePlacement *placement) {
 +	unsigned placement_ram_size = gr_placement_current_ram_size(placement);
 +	images_ram_size -= placement_ram_size;
 +
 +	Display *disp = imlib_context_get_display();
 +	foreach_pixmap(*placement, pixmap, {
 +		if (pixmap)
 +			XFreePixmap(disp, pixmap);
 +	});
 +
 +	placement->first_pixmap = 0;
 +	placement->pixmaps_beyond_the_first.n = 0;
 +	placement->scaled_ch = placement->scaled_cw = 0;
 +
 +	GR_LOG("After unloading placement %u/%u (atime %ld ms ago) "
 +	       "ram: %ld KiB  (- %u KiB)\n",
 +	       placement->image->image_id, placement->placement_id,
 +	       drawing_start_time - placement->atime, images_ram_size / 1024,
 +	       placement_ram_size / 1024);
 +}
 +
 +/// Unload a single pixmap of the placement from RAM.
 +static void gr_unload_pixmap(ImagePlacement *placement, int frameidx) {
 +	Pixmap pixmap = gr_get_frame_pixmap(placement, frameidx);
 +	if (!pixmap)
 +		return;
 +
 +	Display *disp = imlib_context_get_display();
 +	XFreePixmap(disp, pixmap);
 +	gr_set_frame_pixmap(placement, frameidx, 0);
 +	images_ram_size -= gr_placement_single_frame_ram_size(placement);
 +
 +	GR_LOG("After unloading pixmap %ld of "
 +	       "placement %u/%u (atime %ld ms ago) "
 +	       "frame %u (atime %ld ms ago) "
 +	       "ram: %ld KiB  (- %u KiB)\n",
 +	       pixmap, placement->image->image_id, placement->placement_id,
 +	       drawing_start_time - placement->atime, frameidx,
 +	       drawing_start_time -
 +		       gr_get_frame(placement->image, frameidx)->atime,
 +	       images_ram_size / 1024,
 +	       gr_placement_single_frame_ram_size(placement) / 1024);
 +}
 +
 +/// Closes the on-disk cache file of the frame `frame`.
 +static void gr_close_disk_cache_file(ImageFrame *frame) {
 +	if (frame && frame->open_file) {
 +		fclose(frame->open_file);
 +		frame->open_file = NULL;
 +	}
 +}
 +
 +/// Deletes the on-disk cache file corresponding to the frame. The in-ram image
 +/// object (if it exists) is not deleted, placements are not unloaded either.
 +static void gr_delete_imagefile(ImageFrame *frame) {
 +	// It may still be being loaded. Close the file in this case.
 +	gr_close_disk_cache_file(frame);
 +
 +	if (frame->disk_size == 0)
 +		return;
 +
 +	char filename[MAX_FILENAME_SIZE];
 +	gr_get_frame_filename(frame, filename, MAX_FILENAME_SIZE);
 +	remove(filename);
 +
 +	unsigned disk_size = frame->disk_size;
 +	images_disk_size -= disk_size;
 +	frame->image->total_disk_size -= disk_size;
 +	frame->disk_size = 0;
 +
 +	GR_LOG("After deleting image file %u frame %u (atime %ld ms ago) "
 +	       "disk: %ld KiB  (- %u KiB)\n",
 +	       frame->image->image_id, frame->index,
 +	       drawing_start_time - frame->atime, images_disk_size / 1024,
 +	       disk_size / 1024);
 +}
 +
 +/// Deletes all on-disk cache files of the image (for each frame).
 +static void gr_delete_imagefiles(Image *img) {
 +	foreach_frame(*img, frame, {
 +		gr_delete_imagefile(frame);
 +	});
 +}
 +
 +/// Deletes the given placement: unloads, frees the object, erases it from the
 +/// screen in the classic case, but doesn't change the `placements` hash table.
 +static void gr_delete_placement_keep_id(ImagePlacement *placement) {
 +	if (!placement)
 +		return;
 +	GR_LOG("Deleting placement %u/%u\n", placement->image->image_id,
 +	       placement->placement_id);
 +	// Erase the placement from the screen if it's classic and there is some
 +	// saved text underneath.
 +	if (placement->text_underneath && !placement->virtual)
 +		gr_erase_placement(placement);
 +	gr_unload_placement(placement);
 +	kv_destroy(placement->pixmaps_beyond_the_first);
 +	free(placement->text_underneath);
 +	free(placement);
 +	total_placement_count--;
 +}
 +
 +/// Deletes all placements of `img`.
 +static void gr_delete_all_placements(Image *img) {
 +	ImagePlacement *placement = NULL;
 +	kh_foreach_value(img->placements, placement, {
 +		gr_delete_placement_keep_id(placement);
 +	});
 +	kh_clear(id2placement, img->placements);
 +}
 +
 +/// Deletes the given image: unloads, deletes the file, frees the Image object,
 +/// but doesn't change the `images` hash table.
 +static void gr_delete_image_keep_id(Image *img) {
 +	if (!img)
 +		return;
 +	GR_LOG("Deleting image %u\n", img->image_id);
 +	foreach_frame(*img, frame, {
 +		gr_delete_imagefile(frame);
 +		gr_unload_frame(frame);
 +		if (frame->original_filename)
 +			free(frame->original_filename);
 +	});
 +	kv_destroy(img->frames_beyond_the_first);
 +	gr_delete_all_placements(img);
 +	kh_destroy(id2placement, img->placements);
 +	free(img);
 +}
 +
 +/// Deletes the given image: unloads, deletes the file, frees the Image object,
 +/// and also removes it from `images`.
 +static void gr_delete_image(Image *img) {
 +	if (!img)
 +		return;
 +	uint32_t id = img->image_id;
 +	gr_delete_image_keep_id(img);
 +	khiter_t k = kh_get(id2image, images, id);
 +	kh_del(id2image, images, k);
 +}
 +
 +/// Deletes the given placement: unloads, frees the object, erases from the
 +/// screen (in the classic case), and also removes it from `placements`.
 +static void gr_delete_placement(ImagePlacement *placement) {
 +	if (!placement)
 +		return;
 +	uint32_t id = placement->placement_id;
 +	Image *img = placement->image;
 +	gr_delete_placement_keep_id(placement);
 +	khiter_t k = kh_get(id2placement, img->placements, id);
 +	kh_del(id2placement, img->placements, k);
 +}
 +
 +/// Deletes all images and clears `images`.
 +static void gr_delete_all_images() {
 +	Image *img = NULL;
 +	kh_foreach_value(images, img, {
 +		gr_delete_image_keep_id(img);
 +	});
 +	kh_clear(id2image, images);
 +}
 +
 +/// Update the atime of the image.
 +static void gr_touch_image(Image *img) {
 +	img->atime = gr_now_ms();
 +}
 +
 +/// Update the atime of the frame.
 +static void gr_touch_frame(ImageFrame *frame) {
 +	frame->image->atime = frame->atime = gr_now_ms();
 +}
 +
 +/// Update the atime of the placement. Touches the images too.
 +static void gr_touch_placement(ImagePlacement *placement) {
 +	placement->image->atime = placement->atime = gr_now_ms();
 +}
 +
 +/// Creates a new image with the given id. If an image with that id already
 +/// exists, it is deleted first. If the provided id is 0, generates a
 +/// random id.
 +static Image *gr_new_image(uint32_t id) {
 +	if (id == 0) {
 +		do {
 +			id = rand();
 +			// Avoid IDs that don't need full 32 bits.
 +		} while ((id & 0xFF000000) == 0 || (id & 0x00FFFF00) == 0 ||
 +			 gr_find_image(id));
 +		GR_LOG("Generated random image id %u\n", id);
 +	}
 +	Image *img = gr_find_image(id);
 +	gr_delete_image_keep_id(img);
 +	GR_LOG("Creating image %u\n", id);
 +	img = malloc(sizeof(Image));
 +	memset(img, 0, sizeof(Image));
 +	img->placements = kh_init(id2placement);
 +	int ret;
 +	khiter_t k = kh_put(id2image, images, id, &ret);
 +	kh_value(images, k) = img;
 +	img->image_id = id;
 +	gr_touch_image(img);
 +	img->global_command_index = global_command_counter;
 +	return img;
 +}
 +
 +/// Creates a new frame at the end of the frame array. It may be the first frame
 +/// if there are no frames yet.
 +static ImageFrame *gr_append_new_frame(Image *img) {
 +	ImageFrame *frame = NULL;
 +	if (img->first_frame.index == 0 &&
 +	    kv_size(img->frames_beyond_the_first) == 0) {
 +		frame = &img->first_frame;
 +		frame->index = 1;
 +	} else {
 +		frame = kv_pushp(ImageFrame, img->frames_beyond_the_first);
 +		memset(frame, 0, sizeof(ImageFrame));
 +		frame->index = kv_size(img->frames_beyond_the_first) + 1;
 +	}
 +	frame->image = img;
 +	gr_touch_frame(frame);
 +	GR_LOG("Appending frame %d to image %u\n", frame->index, img->image_id);
 +	return frame;
 +}
 +
 +/// Creates a new placement with the given id. If a placement with that id
 +/// already exists, it is deleted first. If the provided id is 0, generates a
 +/// random id.
 +static ImagePlacement *gr_new_placement(Image *img, uint32_t id) {
 +	if (id == 0) {
 +		do {
 +			// Currently we support only 24-bit IDs.
 +			id = rand() & 0xFFFFFF;
 +			// Avoid IDs that need only one byte.
 +		} while ((id & 0x00FFFF00) == 0 || gr_find_placement(img, id));
 +	}
 +	ImagePlacement *placement = gr_find_placement(img, id);
 +	gr_delete_placement_keep_id(placement);
 +	GR_LOG("Creating placement %u/%u\n", img->image_id, id);
 +	placement = malloc(sizeof(ImagePlacement));
 +	memset(placement, 0, sizeof(ImagePlacement));
 +	total_placement_count++;
 +	int ret;
 +	khiter_t k = kh_put(id2placement, img->placements, id, &ret);
 +	kh_value(img->placements, k) = placement;
 +	placement->image = img;
 +	placement->placement_id = id;
 +	gr_touch_placement(placement);
 +	if (img->default_placement == 0)
 +		img->default_placement = id;
 +	return placement;
 +}
 +
 +static int64_t ceil_div(int64_t a, int64_t b) {
 +	return (a + b - 1) / b;
 +}
 +
 +/// Computes the best number of rows and columns for a placement if it's not
 +/// specified, and also adjusts the source rectangle size.
 +static void gr_infer_placement_size_maybe(ImagePlacement *placement) {
 +	// The size of the image.
 +	int image_pix_width = placement->image->pix_width;
 +	int image_pix_height = placement->image->pix_height;
 +	// Negative values are not allowed. Quietly set them to 0.
 +	if (placement->src_pix_x < 0)
 +		placement->src_pix_x = 0;
 +	if (placement->src_pix_y < 0)
 +		placement->src_pix_y = 0;
 +	if (placement->src_pix_width < 0)
 +		placement->src_pix_width = 0;
 +	if (placement->src_pix_height < 0)
 +		placement->src_pix_height = 0;
 +	// If the source rectangle is outside the image, truncate it.
 +	if (placement->src_pix_x > image_pix_width)
 +		placement->src_pix_x = image_pix_width;
 +	if (placement->src_pix_y > image_pix_height)
 +		placement->src_pix_y = image_pix_height;
 +	// If the source rectangle is not specified, use the whole image. If
 +	// it's partially outside the image, truncate it.
 +	if (placement->src_pix_width == 0 ||
 +	    placement->src_pix_x + placement->src_pix_width > image_pix_width)
 +		placement->src_pix_width =
 +			image_pix_width - placement->src_pix_x;
 +	if (placement->src_pix_height == 0 ||
 +	    placement->src_pix_y + placement->src_pix_height > image_pix_height)
 +		placement->src_pix_height =
 +			image_pix_height - placement->src_pix_y;
 +
 +	if (placement->cols != 0 && placement->rows != 0)
 +		return;
 +	if (placement->src_pix_width == 0 || placement->src_pix_height == 0)
 +		return;
 +	if (current_cw == 0 || current_ch == 0)
 +		return;
 +
 +	// If no size is specified, use the image size.
 +	if (placement->cols == 0 && placement->rows == 0) {
 +		placement->cols =
 +			ceil_div(placement->src_pix_width, current_cw);
 +		placement->rows =
 +			ceil_div(placement->src_pix_height, current_ch);
 +		return;
 +	}
 +
 +	// Some applications specify only one of the dimensions.
 +	if (placement->scale_mode == SCALE_MODE_CONTAIN) {
 +		// If we preserve aspect ratio and fit to width/height, the most
 +		// logical thing is to find the minimum size of the
 +		// non-specified dimension that allows the image to fit the
 +		// specified dimension.
 +		if (placement->cols == 0) {
 +			placement->cols = ceil_div(
 +				placement->src_pix_width * placement->rows *
 +					current_ch,
 +				placement->src_pix_height * current_cw);
 +			return;
 +		}
 +		if (placement->rows == 0) {
 +			placement->rows =
 +				ceil_div(placement->src_pix_height *
 +						 placement->cols * current_cw,
 +					 placement->src_pix_width * current_ch);
 +			return;
 +		}
 +	} else {
 +		// Otherwise we stretch the image or preserve the original size.
 +		// In both cases we compute the best number of columns from the
 +		// pixel size and cell size.
 +		// TODO: In the case of stretching it's not the most logical
 +		//       thing to do, may need to revisit in the future.
 +		//       Currently we switch to SCALE_MODE_CONTAIN when only one
 +		//       of the dimensions is specified, so this case shouldn't
 +		//       happen in practice.
 +		if (!placement->cols)
 +			placement->cols =
 +				ceil_div(placement->src_pix_width, current_cw);
 +		if (!placement->rows)
 +			placement->rows =
 +				ceil_div(placement->src_pix_height, current_ch);
 +	}
 +}
 +
 +/// Adjusts the current frame index if enough time has passed since the display
 +/// of the current frame. Also computes the time of the next redraw of this
 +/// image (`img->next_redraw`). The current time is passed as an argument so
 +/// that all animations are in sync.
 +static void gr_update_frame_index(Image *img, Milliseconds now) {
 +	if (img->current_frame == 0) {
 +		img->current_frame_time = now;
 +		img->current_frame = 1;
 +		img->next_redraw = now + MAX(1, img->first_frame.gap);
 +		return;
 +	}
 +	// If the animation is stopped, show the current frame.
 +	if (!img->animation_state ||
 +	    img->animation_state == ANIMATION_STATE_STOPPED ||
 +	    img->animation_state == ANIMATION_STATE_UNSET) {
 +		// The next redraw is never (unless the state is changed).
 +		img->next_redraw = 0;
 +		return;
 +	}
 +	int last_uploaded_frame_index = gr_last_uploaded_frame_index(img);
 +	// If we are loading and we reached the last frame, show the last frame.
 +	if (img->animation_state == ANIMATION_STATE_LOADING &&
 +	    img->current_frame == last_uploaded_frame_index) {
 +		// The next redraw is never (unless the state is changed or
 +		// frames are added).
 +		img->next_redraw = 0;
 +		return;
 +	}
 +
 +	// Check how many milliseconds passed since the current frame was shown.
 +	int passed_ms = now - img->current_frame_time;
 +	// If the animation is looping and too much time has passes, we can
 +	// make a shortcut.
 +	if (img->animation_state == ANIMATION_STATE_LOOPING &&
 +	    img->total_duration > 0 && passed_ms >= img->total_duration) {
 +		passed_ms %= img->total_duration;
 +		img->current_frame_time = now - passed_ms;
 +	}
 +	// Find the next frame.
 +	int original_frame_index = img->current_frame;
 +	while (1) {
 +		ImageFrame *frame = gr_get_frame(img, img->current_frame);
 +		if (!frame) {
 +			// The frame doesn't exist, go to the first frame.
 +			img->current_frame = 1;
 +			img->current_frame_time = now;
 +			img->next_redraw = now + MAX(1, img->first_frame.gap);
 +			return;
 +		}
 +		if (frame->gap >= 0 && passed_ms < frame->gap) {
 +			// Not enough time has passed, we are still in the same
 +			// frame, and it's not a gapless frame.
 +			img->next_redraw =
 +				img->current_frame_time + MAX(1, frame->gap);
 +			return;
 +		}
 +		// Otherwise go to the next frame.
 +		passed_ms -= MAX(0, frame->gap);
 +		if (img->current_frame >= last_uploaded_frame_index) {
 +			// It's the last frame, if the animation is loading,
 +			// remain on it.
 +			if (img->animation_state == ANIMATION_STATE_LOADING) {
 +				img->next_redraw = 0;
 +				return;
 +			}
 +			// Otherwise the animation is looping.
 +			img->current_frame = 1;
 +			// TODO: Support finite number of loops.
 +		} else {
 +			img->current_frame++;
 +		}
 +		// Make sure we don't get stuck in an infinite loop.
 +		if (img->current_frame == original_frame_index) {
 +			// We looped through all frames, but haven't reached the
 +			// next frame yet. This may happen if too much time has
 +			// passed since the last redraw or all the frames are
 +			// gapless. Just move on to the next frame.
 +			img->current_frame++;
 +			if (img->current_frame >
 +			    last_uploaded_frame_index)
 +				img->current_frame = 1;
 +			img->current_frame_time = now;
 +			img->next_redraw = now + MAX(
 +				1, gr_get_frame(img, img->current_frame)->gap);
 +			return;
 +		}
 +		// Adjust the start time of the frame. The next redraw time will
 +		// be set in the next iteration.
 +		img->current_frame_time += MAX(0, frame->gap);
 +	}
 +}
 +
 +////////////////////////////////////////////////////////////////////////////////
 +// Unloading and deleting images to save resources.
 +////////////////////////////////////////////////////////////////////////////////
 +
 +/// Returns whether the original file of the frame is still available (exists,
 +/// is a regular file, has the same size and mtime).
 +static int gr_is_original_file_still_available(ImageFrame *frame) {
 +	if (!frame->original_filename)
 +		return 0;
 +	struct stat st;
 +	if (stat(frame->original_filename, &st) != 0)
 +		return 0;
 +	if (!S_ISREG(st.st_mode))
 +		return 0;
 +	if (st.st_size == 0 || st.st_size > graphics_max_single_image_file_size)
 +		return 0;
 +	if (frame->expected_size && st.st_size != frame->expected_size)
 +		return 0;
 +	if (st.st_mtime != frame->original_file_mtime)
 +		return 0;
 +	return 1;
 +}
 +
 +/// A helper to compare frames by atime for qsort.
 +static int gr_cmp_frames_by_atime(const void *a, const void *b) {
 +	ImageFrame *frame_a = *(ImageFrame *const *)a;
 +	ImageFrame *frame_b = *(ImageFrame *const *)b;
 +	if (frame_a->atime == frame_b->atime)
 +		return frame_a->image->global_command_index -
 +		       frame_b->image->global_command_index;
 +	return frame_a->atime - frame_b->atime;
 +}
 +
 +/// A helper to compare images by atime for qsort.
 +static int gr_cmp_images_by_atime(const void *a, const void *b) {
 +	Image *img_a = *(Image *const *)a;
 +	Image *img_b = *(Image *const *)b;
 +	if (img_a->atime == img_b->atime)
 +		return img_a->global_command_index -
 +		       img_b->global_command_index;
 +	return img_a->atime - img_b->atime;
 +}
 +
 +/// A helper to compare placements by atime for qsort.
 +static int gr_cmp_placements_by_atime(const void *a, const void *b) {
 +	ImagePlacement *p_a = *(ImagePlacement **)a;
 +	ImagePlacement *p_b = *(ImagePlacement **)b;
 +	if (p_a->atime == p_b->atime)
 +		return p_a->image->global_command_index -
 +		       p_b->image->global_command_index;
 +	return p_a->atime - p_b->atime;
 +}
 +
 +typedef kvec_t(Image *) ImageVec;
 +typedef kvec_t(ImagePlacement *) ImagePlacementVec;
 +typedef kvec_t(ImageFrame *) ImageFrameVec;
 +
 +/// Returns an array of pointers to all images sorted by atime.
 +static ImageVec gr_get_images_sorted_by_atime() {
 +	ImageVec vec;
 +	kv_init(vec);
 +	if (kh_size(images) == 0)
 +		return vec;
 +	kv_resize(Image *, vec, kh_size(images));
 +	Image *img = NULL;
 +	kh_foreach_value(images, img, { kv_push(Image *, vec, img); });
 +	qsort(vec.a, kv_size(vec), sizeof(Image *), gr_cmp_images_by_atime);
 +	return vec;
 +}
 +
 +/// Returns an array of pointers to all placements sorted by atime.
 +static ImagePlacementVec gr_get_placements_sorted_by_atime() {
 +	ImagePlacementVec vec;
 +	kv_init(vec);
 +	if (total_placement_count == 0)
 +		return vec;
 +	kv_resize(ImagePlacement *, vec, total_placement_count);
 +	Image *img = NULL;
 +	ImagePlacement *placement = NULL;
 +	kh_foreach_value(images, img, {
 +		kh_foreach_value(img->placements, placement, {
 +			kv_push(ImagePlacement *, vec, placement);
 +		});
 +	});
 +	qsort(vec.a, kv_size(vec), sizeof(ImagePlacement *),
 +	      gr_cmp_placements_by_atime);
 +	return vec;
 +}
 +
 +/// Returns an array of pointers to all frames sorted by atime.
 +static ImageFrameVec gr_get_frames_sorted_by_atime() {
 +	ImageFrameVec frames;
 +	kv_init(frames);
 +	Image *img = NULL;
 +	kh_foreach_value(images, img, {
 +		foreach_frame(*img, frame, {
 +			kv_push(ImageFrame *, frames, frame);
 +		});
 +	});
 +	qsort(frames.a, kv_size(frames), sizeof(ImageFrame *),
 +	      gr_cmp_frames_by_atime);
 +	return frames;
 +}
 +
 +/// An object that can be unloaded from RAM.
 +typedef struct {
 +	/// Some score, probably based on access time. The lower the score, the
 +	/// more likely that the object should be unloaded.
 +	int64_t score;
 +	union {
 +		ImagePlacement *placement;
 +		ImageFrame *frame;
 +	};
 +	/// If zero, the object is the imlib object of `frame`, if non-zero,
 +	/// the object is a pixmap of `frameidx`-th frame of `placement`.
 +	int frameidx;
 +} UnloadableObject;
 +
 +typedef kvec_t(UnloadableObject) UnloadableObjectVec;
 +
 +/// A helper to compare unloadable objects by score for qsort.
 +static int gr_cmp_unloadable_objects(const void *a, const void *b) {
 +	UnloadableObject *obj_a = (UnloadableObject *)a;
 +	UnloadableObject *obj_b = (UnloadableObject *)b;
 +	return obj_a->score - obj_b->score;
 +}
 +
 +/// Unloads an unloadable object from RAM.
 +static void gr_unload_object(UnloadableObject *obj) {
 +	if (obj->frameidx) {
 +		if (obj->placement->protected_frame == obj->frameidx)
 +			return;
 +		gr_unload_pixmap(obj->placement, obj->frameidx);
 +	} else {
 +		gr_unload_frame(obj->frame);
 +	}
 +}
 +
 +/// Returns the recency threshold for an image. Frames that were accessed within
 +/// this threshold from now are considered recent and may be handled
 +/// differently because we may need them again very soon.
 +static Milliseconds gr_recency_threshold(Image *img) {
 +	return img->total_duration * 2 + 1000;
 +}
 +
 +/// Creates an unloadable object for the imlib object of a frame.
 +static UnloadableObject gr_unloadable_object_for_frame(Milliseconds now,
 +						       ImageFrame *frame) {
 +	UnloadableObject obj = {0};
 +	obj.frameidx = 0;
 +	obj.frame = frame;
 +	Milliseconds atime = frame->atime;
 +	obj.score = atime;
 +	if (atime >= now - gr_recency_threshold(frame->image)) {
 +		// This is a recent frame, probably from an active animation.
 +		// Score it above `now` to prefer unloading non-active frames.
 +		// Randomize the score because it's not very clear in which
 +		// order we want to unload them: reloading a frame may require
 +		// reloading other frames.
 +		obj.score = now + 1000 + rand() % 1000;
 +	}
 +	return obj;
 +}
 +
 +/// Creates an unloadable object for a pixmap.
 +static UnloadableObject
 +gr_unloadable_object_for_pixmap(Milliseconds now, ImageFrame *frame,
 +				ImagePlacement *placement) {
 +	UnloadableObject obj = {0};
 +	obj.frameidx = frame->index;
 +	obj.placement = placement;
 +	obj.score = placement->atime;
 +	// Since we don't store pixmap atimes, use the
 +	// oldest atime of the frame and the placement.
 +	Milliseconds atime = MIN(placement->atime, frame->atime);
 +	obj.score = atime;
 +	if (atime >= now - gr_recency_threshold(frame->image)) {
 +		// This is a recent pixmap, probably from an active animation.
 +		// Score it above `now` to prefer unloading non-active frames.
 +		// Also assign higher scores to frames that are closer to the
 +		// current frame (more likely to be used soon).
 +		int num_frames = gr_last_frame_index(frame->image);
 +		int dist = frame->index - frame->image->current_frame;
 +		if (dist < 0)
 +			dist += num_frames;
 +		obj.score =
 +			now + 1000 + (num_frames - dist) * 1000 / num_frames;
 +		// If the pixmap is much larger than the imlib image, prefer to
 +		// unload the pixmap by adding up to -1000 to the score. If the
 +		// imlib image is larger, add up to +1000.
 +		float imlib_size = gr_frame_current_ram_size(frame);
 +		float pixmap_size =
 +			gr_placement_single_frame_ram_size(placement);
 +		obj.score +=
 +			2000 * (imlib_size / (imlib_size + pixmap_size) - 0.5);
 +	}
 +	return obj;
 +}
 +
 +/// Returns an array of unloadable objects sorted by score.
 +static UnloadableObjectVec
 +gr_get_unloadable_objects_sorted_by_score(Milliseconds now) {
 +	UnloadableObjectVec objects;
 +	kv_init(objects);
 +	Image *img = NULL;
 +	ImagePlacement *placement = NULL;
 +	kh_foreach_value(images, img, {
 +		foreach_frame(*img, frame, {
 +			if (frame->imlib_object) {
 +				kv_push(UnloadableObject, objects,
 +					gr_unloadable_object_for_frame(now,
 +								       frame));
 +			}
 +			int frameidx = frame->index;
 +			kh_foreach_value(img->placements, placement, {
 +				if (!gr_get_frame_pixmap(placement, frameidx))
 +					continue;
 +				kv_push(UnloadableObject, objects,
 +					gr_unloadable_object_for_pixmap(
 +						now, frame, placement));
 +			});
 +		});
 +	});
 +	qsort(objects.a, kv_size(objects), sizeof(UnloadableObject),
 +	      gr_cmp_unloadable_objects);
 +	return objects;
 +}
 +
 +/// Returns the limit adjusted by the excess tolerance ratio.
 +static inline unsigned apply_tolerance(unsigned limit) {
 +	return limit + (unsigned)(limit * graphics_excess_tolerance_ratio);
 +}
 +
 +/// Checks RAM and disk cache limits and deletes/unloads some images.
 +static void gr_check_limits() {
 +	Milliseconds now = gr_now_ms();
 +	ImageVec images_sorted = {0};
 +	ImagePlacementVec placements_sorted = {0};
 +	ImageFrameVec frames_sorted = {0};
 +	UnloadableObjectVec objects_sorted = {0};
 +	int images_begin = 0;
 +	int placements_begin = 0;
 +	char changed = 0;
 +	// First reduce the number of images if there are too many.
 +	if (kh_size(images) > apply_tolerance(graphics_max_total_placements)) {
 +		GR_LOG("Too many images: %d\n", kh_size(images));
 +		changed = 1;
 +		images_sorted = gr_get_images_sorted_by_atime();
 +		int to_delete = kv_size(images_sorted) -
 +				graphics_max_total_placements;
 +		for (; images_begin < to_delete; images_begin++)
 +			gr_delete_image(images_sorted.a[images_begin]);
 +	}
 +	// Then reduce the number of placements if there are too many.
 +	if (total_placement_count >
 +	    apply_tolerance(graphics_max_total_placements)) {
 +		GR_LOG("Too many placements: %d\n", total_placement_count);
 +		changed = 1;
 +		placements_sorted = gr_get_placements_sorted_by_atime();
 +		int to_delete = kv_size(placements_sorted) -
 +				graphics_max_total_placements;
 +		for (; placements_begin < to_delete; placements_begin++) {
 +			ImagePlacement *placement =
 +				placements_sorted.a[placements_begin];
 +			if (placement->protected_frame)
 +				break;
 +			gr_delete_placement(placement);
 +		}
 +	}
 +	// Then reduce the size of the image file cache. The files correspond to
 +	// image frames.
 +	if (images_disk_size >
 +	    apply_tolerance(graphics_total_file_cache_size)) {
 +		GR_LOG("Too big disk cache: %ld KiB\n",
 +		       images_disk_size / 1024);
 +		changed = 1;
 +		frames_sorted = gr_get_frames_sorted_by_atime();
 +		for (int i = 0; i < kv_size(frames_sorted); i++) {
 +			if (images_disk_size <= graphics_total_file_cache_size)
 +				break;
 +			gr_delete_imagefile(kv_A(frames_sorted, i));
 +		}
 +	}
 +	// Then unload images from RAM.
 +	if (images_ram_size > apply_tolerance(graphics_max_total_ram_size)) {
 +		changed = 1;
 +		int frames_begin = 0;
 +		GR_LOG("Too much ram: %ld KiB\n", images_ram_size / 1024);
 +		objects_sorted = gr_get_unloadable_objects_sorted_by_score(now);
 +		for (int i = 0; i < kv_size(objects_sorted); i++) {
 +			if (images_ram_size <= graphics_max_total_ram_size)
 +				break;
 +			gr_unload_object(&kv_A(objects_sorted, i));
 +		}
 +	}
 +	if (changed) {
 +		Milliseconds end = gr_now_ms();
 +		GR_LOG("After cleaning:  ram: %ld KiB  disk: %ld KiB  "
 +		       "img count: %d  placement count: %d  Took %ld ms\n",
 +		       images_ram_size / 1024, images_disk_size / 1024,
 +		       kh_size(images), total_placement_count, end - now);
 +	}
 +	kv_destroy(images_sorted);
 +	kv_destroy(placements_sorted);
 +	kv_destroy(frames_sorted);
 +	kv_destroy(objects_sorted);
 +}
 +
 +/// Unloads all images by user request.
 +void gr_unload_images_to_reduce_ram() {
 +	Image *img = NULL;
 +	ImagePlacement *placement = NULL;
 +	kh_foreach_value(images, img, {
 +		kh_foreach_value(img->placements, placement, {
 +			if (placement->protected_frame)
 +				continue;
 +			gr_unload_placement(placement);
 +		});
 +		gr_unload_all_frames(img);
 +	});
 +}
 +
 +////////////////////////////////////////////////////////////////////////////////
 +// Image loading.
 +////////////////////////////////////////////////////////////////////////////////
 +
 +/// Copies `num_pixels` pixels (not bytes!) from a buffer `from` to an imlib2
 +/// image data `to`. The format may be 24 (RGB) or 32 (RGBA), and it's converted
 +/// to imlib2's representation, which is 0xAARRGGBB (having BGRA memory layout
 +/// on little-endian architectures).
 +static inline void gr_copy_pixels(DATA32 *to, unsigned char *from, int format,
 +				  size_t num_pixels) {
 +	size_t pixel_size = format == 24 ? 3 : 4;
 +	if (format == 32) {
 +		for (unsigned i = 0; i < num_pixels; ++i) {
 +			unsigned byte_i = i * pixel_size;
 +			to[i] = ((DATA32)from[byte_i + 2]) |
 +				((DATA32)from[byte_i + 1]) << 8 |
 +				((DATA32)from[byte_i]) << 16 |
 +				((DATA32)from[byte_i + 3]) << 24;
 +		}
 +	} else {
 +		for (unsigned i = 0; i < num_pixels; ++i) {
 +			unsigned byte_i = i * pixel_size;
 +			to[i] = ((DATA32)from[byte_i + 2]) |
 +				((DATA32)from[byte_i + 1]) << 8 |
 +				((DATA32)from[byte_i]) << 16 | 0xFF000000;
 +		}
 +	}
 +}
 +
 +/// Loads uncompressed RGB or RGBA image data from a file.
 +static void gr_load_raw_pixel_data_uncompressed(DATA32 *data, FILE *file,
 +						int format,
 +						size_t total_pixels) {
 +	unsigned char chunk[BUFSIZ];
 +	size_t pixel_size = format == 24 ? 3 : 4;
 +	size_t chunk_size_pix = BUFSIZ / 4;
 +	size_t chunk_size_bytes = chunk_size_pix * pixel_size;
 +	size_t bytes = total_pixels * pixel_size;
 +	for (size_t chunk_start_pix = 0; chunk_start_pix < total_pixels;
 +	     chunk_start_pix += chunk_size_pix) {
 +		size_t read_size = fread(chunk, 1, chunk_size_bytes, file);
 +		size_t read_pixels = read_size / pixel_size;
 +		if (chunk_start_pix + read_pixels > total_pixels)
 +			read_pixels = total_pixels - chunk_start_pix;
 +		gr_copy_pixels(data + chunk_start_pix, chunk, format,
 +			       read_pixels);
 +	}
 +}
 +
 +#define COMPRESSED_CHUNK_SIZE BUFSIZ
 +#define DECOMPRESSED_CHUNK_SIZE (BUFSIZ * 4)
 +
 +/// Loads compressed RGB or RGBA image data from a file.
 +static int gr_load_raw_pixel_data_compressed(DATA32 *data, FILE *file,
 +					     int format, size_t total_pixels) {
 +	size_t pixel_size = format == 24 ? 3 : 4;
 +	unsigned char compressed_chunk[COMPRESSED_CHUNK_SIZE];
 +	unsigned char decompressed_chunk[DECOMPRESSED_CHUNK_SIZE];
 +
 +	z_stream strm;
 +	strm.zalloc = Z_NULL;
 +	strm.zfree = Z_NULL;
 +	strm.opaque = Z_NULL;
 +	strm.next_out = decompressed_chunk;
 +	strm.avail_out = DECOMPRESSED_CHUNK_SIZE;
 +	strm.avail_in = 0;
 +	strm.next_in = Z_NULL;
 +	int ret = inflateInit(&strm);
 +	if (ret != Z_OK)
 +	    return 1;
 +
 +	int error = 0;
 +	int progress = 0;
 +	size_t total_copied_pixels = 0;
 +	while (1) {
 +		// If we don't have enough data in the input buffer, try to read
 +		// from the file.
 +		if (strm.avail_in <= COMPRESSED_CHUNK_SIZE / 4) {
 +			// Move the existing data to the beginning.
 +			memmove(compressed_chunk, strm.next_in, strm.avail_in);
 +			strm.next_in = compressed_chunk;
 +			// Read more data.
 +			size_t bytes_read = fread(
 +				compressed_chunk + strm.avail_in, 1,
 +				COMPRESSED_CHUNK_SIZE - strm.avail_in, file);
 +			strm.avail_in += bytes_read;
 +			if (bytes_read != 0)
 +				progress = 1;
 +		}
 +
 +		// Try to inflate the data.
 +		int ret = inflate(&strm, Z_SYNC_FLUSH);
 +		if (ret == Z_MEM_ERROR || ret == Z_DATA_ERROR) {
 +			error = 1;
 +			fprintf(stderr,
 +				"error: could not decompress the image, error "
 +				"%s\n",
 +				ret == Z_MEM_ERROR ? "Z_MEM_ERROR"
 +						   : "Z_DATA_ERROR");
 +			break;
 +		}
 +
 +		// Copy the data from the output buffer to the image.
 +		size_t full_pixels =
 +			(DECOMPRESSED_CHUNK_SIZE - strm.avail_out) / pixel_size;
 +		// Make sure we don't overflow the image.
 +		if (full_pixels > total_pixels - total_copied_pixels)
 +			full_pixels = total_pixels - total_copied_pixels;
 +		if (full_pixels > 0) {
 +			// Copy pixels.
 +			gr_copy_pixels(data, decompressed_chunk, format,
 +				       full_pixels);
 +			data += full_pixels;
 +			total_copied_pixels += full_pixels;
 +			if (total_copied_pixels >= total_pixels) {
 +				// We filled the whole image, there may be some
 +				// data left, but we just truncate it.
 +				break;
 +			}
 +			// Move the remaining data to the beginning.
 +			size_t copied_bytes = full_pixels * pixel_size;
 +			size_t leftover =
 +				(DECOMPRESSED_CHUNK_SIZE - strm.avail_out) -
 +				copied_bytes;
 +			memmove(decompressed_chunk,
 +				decompressed_chunk + copied_bytes, leftover);
 +			strm.next_out -= copied_bytes;
 +			strm.avail_out += copied_bytes;
 +			progress = 1;
 +		}
 +
 +		// If we haven't made any progress, then we have reached the end
 +		// of both the file and the inflated data.
 +		if (!progress)
 +			break;
 +		progress = 0;
 +	}
 +
 +	inflateEnd(&strm);
 +	return error;
 +}
 +
 +#undef COMPRESSED_CHUNK_SIZE
 +#undef DECOMPRESSED_CHUNK_SIZE
 +
 +/// Load the image from a file containing raw pixel data (RGB or RGBA), the data
 +/// may be compressed.
 +static Imlib_Image gr_load_raw_pixel_data(ImageFrame *frame,
 +					  const char *filename) {
 +	size_t total_pixels = frame->data_pix_width * frame->data_pix_height;
 +	if (total_pixels * 4 > graphics_max_single_image_ram_size) {
 +		fprintf(stderr,
 +			"error: image %u frame %u is too big too load: %zu > %u\n",
 +			frame->image->image_id, frame->index, total_pixels * 4,
 +			graphics_max_single_image_ram_size);
 +		return NULL;
 +	}
 +
 +	FILE* file = fopen(filename, "rb");
 +	if (!file) {
 +		fprintf(stderr,
 +			"error: could not open image file: %s\n",
 +			sanitized_filename(filename));
 +		return NULL;
 +	}
 +
 +	Imlib_Image image = imlib_create_image(frame->data_pix_width,
 +					       frame->data_pix_height);
 +	if (!image) {
 +		fprintf(stderr,
 +			"error: could not create an image of size %d x %d\n",
 +			frame->data_pix_width, frame->data_pix_height);
 +		fclose(file);
 +		return NULL;
 +	}
 +
 +	imlib_context_set_image(image);
 +	imlib_image_set_has_alpha(1);
 +	DATA32* data = imlib_image_get_data();
 +
 +	if (frame->compression == 0) {
 +		gr_load_raw_pixel_data_uncompressed(data, file, frame->format,
 +						    total_pixels);
 +	} else {
 +		int ret = gr_load_raw_pixel_data_compressed(
 +			data, file, frame->format, total_pixels);
 +		if (ret != 0) {
 +			imlib_image_put_back_data(data);
 +			imlib_free_image();
 +			fclose(file);
 +			return NULL;
 +		}
 +	}
 +
 +	fclose(file);
 +	imlib_image_put_back_data(data);
 +	return image;
 +}
 +
 +/// Loads the unscaled frame into RAM as an imlib object. The frame imlib object
 +/// is fully composed on top of the background frame. If the frame is already
 +/// loaded, does nothing. Loading may fail, in which case the status of the
 +/// frame will be set to STATUS_RAM_LOADING_ERROR.
 +static void gr_load_imlib_object(ImageFrame *frame) {
 +	if (frame->imlib_object)
 +		return;
 +
 +	// If the image is uninitialized or uploading has failed, or the file
 +	// has been deleted, we cannot load the image.
 +	if (frame->status < STATUS_UPLOADING_SUCCESS)
 +		return;
 +	if (frame->disk_size == 0) {
 +		// In some cases the original image file may still be available,
 +		// try to restore it.
 +		gr_try_restore_imagefile(frame);
 +	}
 +	if (frame->disk_size == 0) {
 +		if (frame->status != STATUS_RAM_LOADING_ERROR &&
 +		    frame->status >= STATUS_UPLOADING_SUCCESS) {
 +			fprintf(stderr,
 +				"error: cached image was deleted: %u frame %u\n",
 +				frame->image->image_id, frame->index);
 +		}
 +		frame->status = STATUS_RAM_LOADING_ERROR;
 +		return;
 +	}
 +
 +	// Prevent recursive dependences between frames.
 +	if (frame->ram_loading_in_progress) {
 +		if (frame->status != STATUS_RAM_LOADING_ERROR) {
 +			fprintf(stderr,
 +				"error: recursive loading of image %u frame "
 +				"%u\n",
 +				frame->image->image_id, frame->index);
 +		}
 +		frame->status = STATUS_RAM_LOADING_ERROR;
 +		return;
 +	}
 +	frame->ram_loading_in_progress = 1;
 +
 +	// Load the background frame if needed. Hopefully it's not recursive.
 +	ImageFrame *bg_frame = NULL;
 +	if (frame->background_frame_index) {
 +		bg_frame = gr_get_frame(frame->image,
 +					frame->background_frame_index);
 +		if (!bg_frame) {
 +			if (frame->status != STATUS_RAM_LOADING_ERROR) {
 +				fprintf(stderr,
 +					"error: could not find background "
 +					"frame %d for image %u frame %d\n",
 +					frame->background_frame_index,
 +					frame->image->image_id, frame->index);
 +				frame->status = STATUS_RAM_LOADING_ERROR;
 +			}
 +			return;
 +		}
 +		gr_load_imlib_object(bg_frame);
 +		if (!bg_frame->imlib_object) {
 +			if (frame->status != STATUS_RAM_LOADING_ERROR) {
 +				fprintf(stderr,
 +					"error: could not load background "
 +					"frame %d for image %u frame %d\n",
 +					frame->background_frame_index,
 +					frame->image->image_id, frame->index);
 +			}
 +			frame->status = STATUS_RAM_LOADING_ERROR;
 +			return;
 +		}
 +	}
 +
 +	frame->ram_loading_in_progress = 0;
 +
 +	// We exclude background frames from the time to load the frame.
 +	Milliseconds loading_start = gr_now_ms();
 +
 +	// Load the frame data image.
 +	Imlib_Image frame_data_image = NULL;
 +	char filename[MAX_FILENAME_SIZE];
 +	gr_get_frame_filename(frame, filename, MAX_FILENAME_SIZE);
 +	GR_LOG("Loading image: %s\n", sanitized_filename(filename));
 +	if (frame->format == 100)
 +		frame_data_image = imlib_load_image(filename);
 +	if (frame->format == 32 || frame->format == 24)
 +		frame_data_image = gr_load_raw_pixel_data(frame, filename);
 +	debug_loaded_files_counter++;
 +
 +	if (!frame_data_image) {
 +		if (frame->status != STATUS_RAM_LOADING_ERROR) {
 +			fprintf(stderr, "error: could not load image: %s\n",
 +				sanitized_filename(filename));
 +		}
 +		frame->status = STATUS_RAM_LOADING_ERROR;
 +		return;
 +	}
 +
 +	imlib_context_set_image(frame_data_image);
 +	int frame_data_width = imlib_image_get_width();
 +	int frame_data_height = imlib_image_get_height();
 +
 +	// Check that the size of the image we are loading does not exceed the
 +	// limit.
 +	if (frame_data_width * frame_data_height * 4 >
 +	    graphics_max_single_image_ram_size) {
 +		if (frame->status != STATUS_RAM_LOADING_ERROR) {
 +			fprintf(stderr,
 +				"error: image %u frame %u is too big too load: "
 +				"%d x %d * 4 = %d > %u\n",
 +				frame->image->image_id, frame->index,
 +				frame_data_width, frame_data_height,
 +				frame_data_width * frame_data_height * 4,
 +				graphics_max_single_image_ram_size);
 +		}
 +		imlib_free_image();
 +		frame->status = STATUS_RAM_LOADING_ERROR;
 +		return;
 +	}
 +
 +	GR_LOG("Successfully loaded, size %d x %d\n", frame_data_width,
 +	       frame_data_height);
 +	// If imlib loading succeeded, and it is the first frame, set the
 +	// information about the original image size, unless it's already set.
 +	if (frame->index == 1 && frame->image->pix_width == 0 &&
 +	    frame->image->pix_height == 0) {
 +		frame->image->pix_width = frame_data_width;
 +		frame->image->pix_height = frame_data_height;
 +	}
 +
 +	int image_width = frame->image->pix_width;
 +	int image_height = frame->image->pix_height;
 +
 +	// Compose the image with the background color or frame.
 +	if (frame->background_color != 0 || bg_frame ||
 +	    image_width != frame_data_width ||
 +	    image_height != frame_data_height) {
 +		GR_LOG("Composing the frame bg = 0x%08X, bgframe = %d\n",
 +		       frame->background_color, frame->background_frame_index);
 +		Imlib_Image composed_image = imlib_create_image(
 +			image_width, image_height);
 +		imlib_context_set_image(composed_image);
 +		imlib_image_set_has_alpha(1);
 +		imlib_context_set_anti_alias(0);
 +
 +		// Start with the background frame or color.
 +		imlib_context_set_blend(0);
 +		if (bg_frame && bg_frame->imlib_object) {
 +			imlib_blend_image_onto_image(
 +				bg_frame->imlib_object, 1, 0, 0,
 +				image_width, image_height, 0, 0,
 +				image_width, image_height);
 +		} else {
 +			int r = (frame->background_color >> 24) & 0xFF;
 +			int g = (frame->background_color >> 16) & 0xFF;
 +			int b = (frame->background_color >> 8) & 0xFF;
 +			int a = frame->background_color & 0xFF;
 +			imlib_context_set_color(r, g, b, a);
 +			imlib_image_fill_rectangle(0, 0, image_width,
 +						   image_height);
 +		}
 +
 +		// Blend the frame data image onto the background.
 +		imlib_context_set_blend(1);
 +		imlib_blend_image_onto_image(
 +			frame_data_image, 1, 0, 0, frame->data_pix_width,
 +			frame->data_pix_height, frame->x, frame->y,
 +			frame->data_pix_width, frame->data_pix_height);
 +
 +		// Free the frame data image.
 +		imlib_context_set_image(frame_data_image);
 +		imlib_free_image();
 +
 +		frame_data_image = composed_image;
 +	}
 +
 +	frame->imlib_object = frame_data_image;
 +
 +	images_ram_size += gr_frame_current_ram_size(frame);
 +	frame->status = STATUS_RAM_LOADING_SUCCESS;
 +
 +	Milliseconds loading_end = gr_now_ms();
 +	GR_LOG("After loading image %u frame %d ram: %ld KiB  (+ %u KiB)  Took "
 +	       "%ld ms\n",
 +	       frame->image->image_id, frame->index, images_ram_size / 1024,
 +	       gr_frame_current_ram_size(frame) / 1024,
 +	       loading_end - loading_start);
 +}
 +
 +/// Premultiplies the alpha channel of the image data. The data is an array of
 +/// pixels such that each pixel is a 32-bit integer in the format 0xAARRGGBB.
 +static void gr_premultiply_alpha(DATA32 *data, size_t num_pixels) {
 +	for (size_t i = 0; i < num_pixels; ++i) {
 +		DATA32 pixel = data[i];
 +		unsigned char a = pixel >> 24;
 +		if (a == 0) {
 +			data[i] = 0;
 +		} else if (a != 255) {
 +			unsigned char b = (pixel & 0xFF) * a / 255;
 +			unsigned char g = ((pixel >> 8) & 0xFF) * a / 255;
 +			unsigned char r = ((pixel >> 16) & 0xFF) * a / 255;
 +			data[i] = (a << 24) | (r << 16) | (g << 8) | b;
 +		}
 +	}
 +}
 +
 +/// Computes the pixmap transformation, which is essentially the destination
 +/// rectangle for drawing an image placement in a box of size `cols*cw` x
 +/// `rows*ch`. The destination rectangle depends on the parameters of the
 +/// placement, like scaling mode. The computed transformation is stored in the
 +/// placement.
 +void gr_compute_pixmap_transformation(ImagePlacement *placement) {
 +	// Infer the placement size if needed.
 +	gr_infer_placement_size_maybe(placement);
 +
 +	// The size of the box in which the image is placed.
 +	int box_w = (int)placement->cols * placement->scaled_cw;
 +	int box_h = (int)placement->rows * placement->scaled_ch;
 +
 +	int src_w = placement->src_pix_width;
 +	int src_h = placement->src_pix_height;
 +
 +	// Whether the box is too small to use the true size of the image.
 +	char box_too_small = box_w < src_w || box_h < src_h;
 +	char mode = placement->scale_mode;
 +
 +	PixmapTransformation *tr = &placement->pixmap_transformation;
 +
 +	if (src_w <= 0 || src_h <= 0) {
 +		tr->dst_x = tr->dst_y = tr->dst_w = tr->dst_h = 0;
 +	} else if (mode == SCALE_MODE_FILL) {
 +		tr->dst_x = tr->dst_y = 0;
 +		tr->dst_w = box_w;
 +		tr->dst_h = box_h;
 +	} else if (mode == SCALE_MODE_NONE ||
 +		   (mode == SCALE_MODE_NONE_OR_CONTAIN && !box_too_small)) {
 +		tr->dst_x = tr->dst_y = 0;
 +		tr->dst_w = src_w;
 +		tr->dst_h = src_h;
 +	} else {
 +		if (mode != SCALE_MODE_CONTAIN &&
 +		    mode != SCALE_MODE_NONE_OR_CONTAIN) {
 +			fprintf(stderr,
 +				"warning: unknown scale mode %u, using "
 +				"'contain' instead\n",
 +				mode);
 +		}
 +		if (box_w * src_h > src_w * box_h) {
 +			// If the box is wider than the original image, fit to
 +			// height.
 +			tr->dst_h = box_h;
 +			tr->dst_y = 0;
 +			tr->dst_w = src_w * box_h / src_h;
 +			tr->dst_x = (box_w - tr->dst_w) / 2;
 +		} else {
 +			// Otherwise, fit to width.
 +			tr->dst_w = box_w;
 +			tr->dst_x = 0;
 +			tr->dst_h = src_h * box_w / src_w;
 +			tr->dst_y = (box_h - tr->dst_h) / 2;
 +		}
 +	}
 +
 +	// Make sure that the size of the destination image is non-zero.
 +	tr->dst_w = MAX(1, tr->dst_w);
 +	tr->dst_h = MAX(1, tr->dst_h);
 +
 +	// Normally we want the pixmap to be exactly the size of the destination
 +	// rectangle.
 +	tr->pixmap_w = tr->dst_w;
 +	tr->pixmap_h = tr->dst_h;
 +	// However, if the pixmap would be larger than the source image, use the
 +	// source image size. The upscaling will be done by XRender then.
 +	if (tr->pixmap_w * tr->pixmap_h > src_w * src_h) {
 +		tr->pixmap_w = MAX(1, src_w);
 +		tr->pixmap_h = MAX(1, src_h);
 +	}
 +
 +	// If the pixmap would be over the limit, scale it down.
 +	if (tr->pixmap_w * tr->pixmap_h * 4 >
 +	    graphics_max_single_image_ram_size) {
 +		double scale = sqrt((double)graphics_max_single_image_ram_size /
 +				    (tr->pixmap_w * tr->pixmap_h * 4));
 +		tr->pixmap_w = MAX(1, (int)(tr->pixmap_w * scale));
 +		tr->pixmap_h = MAX(1, (int)(tr->pixmap_h * scale));
 +	}
 +}
 +
 +/// Creates and returns a scaled imlib image for the image placement. The
 +/// original imlib object must be loaded and the placement size must be inferred
 +/// by the caller (by calling `gr_compute_pixmap_transformation`). The caller is
 +/// responsible for freeing the returned image.
 +Imlib_Image gr_create_scaled_image_object(ImagePlacement *placement,
 +					  ImageFrame *frame) {
 +	// The source rectangle (inside the original image).
 +	int src_x = placement->src_pix_x;
 +	int src_y = placement->src_pix_y;
 +	int src_w = placement->src_pix_width;
 +	int src_h = placement->src_pix_height;
 +	// The pixmap dimensions.
 +	int pixmap_w = placement->pixmap_transformation.pixmap_w;
 +	int pixmap_h = placement->pixmap_transformation.pixmap_h;
 +
 +	if (pixmap_w * pixmap_h * 4 > graphics_max_single_image_ram_size) {
 +		fprintf(stderr,
 +			"error: placement %u/%u would be too big to load: %d x "
 +			"%d x 4 > %u\n",
 +			placement->image->image_id, placement->placement_id,
 +			pixmap_w, pixmap_h, graphics_max_single_image_ram_size);
 +		return 0;
 +	}
 +
 +	if (pixmap_w == 0 || pixmap_h == 0)
 +		fprintf(stderr, "warning: image of zero size\n");
 +
 +	imlib_context_set_image(frame->imlib_object);
 +	imlib_context_set_anti_alias(1);
 +	imlib_context_set_blend(1);
 +
 +	return imlib_create_cropped_scaled_image(src_x, src_y, src_w, src_h,
 +						 pixmap_w, pixmap_h);
 +}
 +
 +/// Creates a pixmap for the frame of an image placement. The pixmap contains
 +/// the image data correctly scaled and fit to the box defined by the number of
 +/// rows/columns of the image placement and the provided cell dimensions in
 +/// pixels. If the placement is already loaded, it will be reloaded only if the
 +/// cell dimensions have changed.
 +Pixmap gr_load_pixmap(ImagePlacement *placement, int frameidx, int cw, int ch) {
 +	Milliseconds loading_start = gr_now_ms();
 +	Image *img = placement->image;
 +	ImageFrame *frame = gr_get_frame(img, frameidx);
 +
 +	// Update the atime unconditionally.
 +	gr_touch_placement(placement);
 +	if (frame)
 +		gr_touch_frame(frame);
 +
 +	// If cw or ch are different, unload all the pixmaps and recompute the
 +	// pixmap geometry and transformation (shared for all pixmaps).
 +	if (placement->scaled_cw != cw || placement->scaled_ch != ch) {
 +		gr_unload_placement(placement);
 +		placement->scaled_cw = cw;
 +		placement->scaled_ch = ch;
 +		gr_compute_pixmap_transformation(placement);
 +	}
 +
 +	// If it's already loaded, do nothing.
 +	Pixmap pixmap = gr_get_frame_pixmap(placement, frameidx);
 +	if (pixmap)
 +		return pixmap;
 +
 +	GR_LOG("Loading placement: %u/%u frame %u\n", img->image_id,
 +	       placement->placement_id, frameidx);
 +
 +	if (placement->pixmap_transformation.pixmap_w == 0 ||
 +	    placement->pixmap_transformation.pixmap_h == 0) {
 +		GR_LOG("Not loading because the pixmap size is zero\n");
 +		return 0;
 +	}
 +
 +	// Load the imlib object for the frame.
 +	if (!frame) {
 +		fprintf(stderr,
 +			"error: could not find frame %u for image %u\n",
 +			frameidx, img->image_id);
 +		return 0;
 +	}
 +	gr_load_imlib_object(frame);
 +	if (!frame->imlib_object)
 +		return 0;
 +
 +	// Create the scaled image. This is temporary, we will upload to the X
 +	// server, and then delete immediately.
 +	Imlib_Image scaled_image =
 +		gr_create_scaled_image_object(placement, frame);
 +	if (!scaled_image)
 +		return 0;
 +	imlib_context_set_image(scaled_image);
 +	int pixmap_w = imlib_image_get_width();
 +	int pixmap_h = imlib_image_get_height();
 +
 +	// XRender needs the alpha channel premultiplied.
 +	DATA32 *data = imlib_image_get_data();
 +	gr_premultiply_alpha(data, pixmap_w * pixmap_h);
 +
 +	// Upload the image to the X server.
 +	Display *disp = imlib_context_get_display();
 +	Visual *vis = imlib_context_get_visual();
 +	Colormap cmap = imlib_context_get_colormap();
 +	Drawable drawable = imlib_context_get_drawable();
 +	if (!drawable)
 +		drawable = DefaultRootWindow(disp);
 +	pixmap = XCreatePixmap(disp, drawable, pixmap_w, pixmap_h, 32);
 +	XVisualInfo visinfo = {0};
 +	Status visual_found = XMatchVisualInfo(disp, DefaultScreen(disp), 32,
 +					       TrueColor, &visinfo) ||
 +			      XMatchVisualInfo(disp, DefaultScreen(disp), 24,
 +					       TrueColor, &visinfo);
 +	if (!visual_found) {
 +		fprintf(stderr,
 +			"error: could not find 32-bit TrueColor visual\n");
 +		// Proceed anyway.
 +		visinfo.visual = NULL;
 +	}
 +	XImage *ximage = XCreateImage(disp, visinfo.visual, 32, ZPixmap, 0,
 +				      (char *)data, pixmap_w, pixmap_h, 32, 0);
 +	if (!ximage) {
 +		fprintf(stderr, "error: could not create XImage\n");
 +		imlib_image_put_back_data(data);
 +		imlib_free_image();
 +		return 0;
 +	}
 +	GC gc = XCreateGC(disp, pixmap, 0, NULL);
 +	XPutImage(disp, pixmap, gc, ximage, 0, 0, 0, 0, pixmap_w, pixmap_h);
 +	XFreeGC(disp, gc);
 +	// XDestroyImage will free the data as well, but it is managed by imlib,
 +	// so set it to NULL.
 +	ximage->data = NULL;
 +	XDestroyImage(ximage);
 +	imlib_image_put_back_data(data);
 +	imlib_free_image();
 +
 +	// Assign the pixmap to the frame and increase the ram size.
 +	gr_set_frame_pixmap(placement, frameidx, pixmap);
 +	images_ram_size += gr_placement_single_frame_ram_size(placement);
 +	debug_loaded_pixmaps_counter++;
 +
 +	Milliseconds loading_end = gr_now_ms();
 +	GR_LOG("After loading placement %u/%u frame %d ram: %ld KiB  (+ %u "
 +	       "KiB)  Took %ld ms\n",
 +	       frame->image->image_id, placement->placement_id, frame->index,
 +	       images_ram_size / 1024,
 +	       gr_placement_single_frame_ram_size(placement) / 1024,
 +	       loading_end - loading_start);
 +
 +	// Free up ram if needed, but keep the pixmap we've loaded no matter
 +	// what.
 +	placement->protected_frame = frameidx;
 +	gr_check_limits();
 +	placement->protected_frame = 0;
 +
 +	return pixmap;
 +}
 +
 +////////////////////////////////////////////////////////////////////////////////
 +// Initialization and deinitialization.
 +////////////////////////////////////////////////////////////////////////////////
 +
 +/// Creates a temporary directory.
 +static int gr_create_cache_dir() {
 +	strncpy(cache_dir, graphics_cache_dir_template, sizeof(cache_dir));
 +	if (!mkdtemp(cache_dir)) {
 +		fprintf(stderr,
 +			"error: could not create temporary dir from template "
 +			"%s\n",
 +			sanitized_filename(cache_dir));
 +		return 0;
 +	}
 +	fprintf(stderr, "Graphics cache directory: %s\n", cache_dir);
 +	return 1;
 +}
 +
 +/// Checks whether `tmp_dir` exists and recreates it if it doesn't.
 +static void gr_make_sure_tmpdir_exists() {
 +	struct stat st;
 +	if (stat(cache_dir, &st) == 0 && S_ISDIR(st.st_mode))
 +		return;
 +	fprintf(stderr,
 +		"error: %s is not a directory, will need to create a new "
 +		"graphics cache directory\n",
 +		sanitized_filename(cache_dir));
 +	gr_create_cache_dir();
 +}
 +
 +/// Initialize the graphics module.
 +void gr_init(Display *disp, Visual *vis, Colormap cm) {
 +	// Set the initialization time.
 +	clock_gettime(CLOCK_MONOTONIC, &initialization_time);
 +
 +	// Create the temporary dir.
 +	if (!gr_create_cache_dir())
 +		abort();
 +
 +	// Initialize imlib.
 +	imlib_context_set_display(disp);
 +	imlib_context_set_visual(vis);
 +	imlib_context_set_colormap(cm);
 +	imlib_context_set_anti_alias(1);
 +	imlib_context_set_blend(1);
 +	// Imlib2 checks only the file name when caching, which is not enough
 +	// for us since we reuse file names. Disable caching.
 +	imlib_set_cache_size(0);
 +
 +	// Prepare for color inversion.
 +	for (size_t i = 0; i < 256; ++i)
 +		reverse_table[i] = 255 - i;
 +
 +	// Create data structures.
 +	images = kh_init(id2image);
 +	kv_init(next_redraw_times);
 +
 +	atexit(gr_deinit);
 +}
 +
 +/// Deinitialize the graphics module.
 +void gr_deinit() {
 +	// Remove the cache dir.
 +	remove(cache_dir);
 +	kv_destroy(next_redraw_times);
 +	if (images) {
 +		// Delete all images.
 +		gr_delete_all_images();
 +		// Destroy the data structures.
 +		kh_destroy(id2image, images);
 +		images = NULL;
 +	}
 +}
 +
 +////////////////////////////////////////////////////////////////////////////////
 +// Dumping, debugging, and image preview.
 +////////////////////////////////////////////////////////////////////////////////
 +
 +/// Returns a string containing a time difference in a human-readable format.
 +/// Uses a static buffer, so be careful.
 +static const char *gr_ago(Milliseconds diff) {
 +	static char result[32];
 +	double seconds = (double)diff / 1000.0;
 +	if (seconds < 1)
 +		snprintf(result, sizeof(result), "%.2f sec ago", seconds);
 +	else if (seconds < 60)
 +		snprintf(result, sizeof(result), "%d sec ago", (int)seconds);
 +	else if (seconds < 3600)
 +		snprintf(result, sizeof(result), "%d min %d sec ago",
 +			 (int)(seconds / 60), (int)(seconds) % 60);
 +	else {
 +		snprintf(result, sizeof(result), "%d hr %d min %d sec ago",
 +			 (int)(seconds / 3600), (int)(seconds) % 3600 / 60,
 +			 (int)(seconds) % 60);
 +	}
 +	return result;
 +}
 +
 +/// Prints to `file` with an indentation of `ind` spaces.
 +static void fprintf_ind(FILE *file, int ind, const char *format, ...) {
 +	fprintf(file, "%*s", ind, "");
 +	va_list args;
 +	va_start(args, format);
 +	vfprintf(file, format, args);
 +	va_end(args);
 +}
 +
 +/// Dumps the image info to `file` with an indentation of `ind` spaces.
 +static void gr_dump_image_info(FILE *file, Image *img, int ind) {
 +	if (!img) {
 +		fprintf_ind(file, ind, "Image is NULL\n");
 +		return;
 +	}
 +	Milliseconds now = gr_now_ms();
 +	fprintf_ind(file, ind, "Image %u\n", img->image_id);
 +	ind += 4;
 +	fprintf_ind(file, ind, "number: %u\n", img->image_number);
 +	fprintf_ind(file, ind, "global command index: %lu\n",
 +		img->global_command_index);
 +	fprintf_ind(file, ind, "accessed: %ld  %s\n", img->atime,
 +		    gr_ago(now - img->atime));
 +	fprintf_ind(file, ind, "pix size: %ux%u\n", img->pix_width,
 +		    img->pix_height);
 +	fprintf_ind(file, ind, "cur frame start time: %ld  %s\n",
 +		    img->current_frame_time,
 +		    gr_ago(now - img->current_frame_time));
 +	if (img->next_redraw)
 +		fprintf_ind(file, ind, "next redraw: %ld  in %ld ms\n",
 +			    img->next_redraw, img->next_redraw - now);
 +	fprintf_ind(file, ind, "total disk size: %u KiB\n",
 +		img->total_disk_size / 1024);
 +	fprintf_ind(file, ind, "total duration: %d\n", img->total_duration);
 +	fprintf_ind(file, ind, "frames: %d\n", gr_last_frame_index(img));
 +	fprintf_ind(file, ind, "cur frame: %d\n", img->current_frame);
 +	fprintf_ind(file, ind, "animation state: %d\n", img->animation_state);
 +	fprintf_ind(file, ind, "default_placement: %u\n",
 +		    img->default_placement);
 +}
 +
 +/// Dumps the frame info to `file` with an indentation of `ind` spaces.
 +static void gr_dump_frame_info(FILE *file, ImageFrame *frame, int ind) {
 +	if (!frame) {
 +		fprintf_ind(file, ind, "Frame is NULL\n");
 +		return;
 +	}
 +	Milliseconds now = gr_now_ms();
 +	fprintf_ind(file, ind, "Frame %d\n", frame->index);
 +	ind += 4;
 +	if (frame->index == 0) {
 +		fprintf_ind(file, ind, "NOT INITIALIZED\n");
 +		return;
 +	}
 +	if (frame->original_filename) {
 +		fprintf_ind(file, ind, "original filename (sanitized): %s\n",
 +			    sanitized_filename(frame->original_filename));
 +		fprintf_ind(file, ind, "original file %s\n",
 +			    gr_is_original_file_still_available(frame)
 +				    ? "is still available"
 +				    : "is NOT available anymore");
 +	}
 +	if (frame->uploading_failure)
 +		fprintf_ind(file, ind, "uploading failure: %s\n",
 +			    image_uploading_failure_strings
 +				    [frame->uploading_failure]);
 +	fprintf_ind(file, ind, "gap: %d\n", frame->gap);
 +	fprintf_ind(file, ind, "accessed: %ld  %s\n", frame->atime,
 +		    gr_ago(now - frame->atime));
 +	fprintf_ind(file, ind, "data pix size: %ux%u\n", frame->data_pix_width,
 +		    frame->data_pix_height);
 +	char filename[MAX_FILENAME_SIZE];
 +	gr_get_frame_filename(frame, filename, MAX_FILENAME_SIZE);
 +	if (access(filename, F_OK) != -1)
 +		fprintf_ind(file, ind, "file: %s\n",
 +			    sanitized_filename(filename));
 +	else
 +		fprintf_ind(file, ind, "not on disk\n");
 +	fprintf_ind(file, ind, "disk size: %u KiB\n", frame->disk_size / 1024);
 +	if (frame->imlib_object) {
 +		unsigned ram_size = gr_frame_current_ram_size(frame);
 +		fprintf_ind(file, ind,
 +			    "loaded into ram, size: %d "
 +			    "KiB\n",
 +			    ram_size / 1024);
 +	} else {
 +		fprintf_ind(file, ind, "not loaded into ram\n");
 +	}
 +}
 +
 +/// Dumps the placement info to `file` with an indentation of `ind` spaces.
 +static void gr_dump_placement_info(FILE *file, ImagePlacement *placement,
 +				   int ind) {
 +	if (!placement) {
 +		fprintf_ind(file, ind, "Placement is NULL\n");
 +		return;
 +	}
 +	Milliseconds now = gr_now_ms();
 +	fprintf_ind(file, ind, "Placement %u\n", placement->placement_id);
 +	ind += 4;
 +	fprintf_ind(file, ind, "accessed: %ld  %s\n", placement->atime,
 +		    gr_ago(now - placement->atime));
 +	fprintf_ind(file, ind, "scale_mode: %u\n", placement->scale_mode);
 +	fprintf_ind(file, ind, "size: %u cols x %u rows\n", placement->cols,
 +		    placement->rows);
 +	fprintf_ind(file, ind, "cell size: %ux%u\n", placement->scaled_cw,
 +		    placement->scaled_ch);
 +	PixmapTransformation *tr = &placement->pixmap_transformation;
 +	fprintf_ind(file, ind, "pixmap size: %ux%u\n", tr->pixmap_w,
 +		    tr->pixmap_h);
 +	fprintf_ind(file, ind, "dst size: %ux%u  offset: (%d, %d)\n", tr->dst_w,
 +		    tr->dst_h, tr->dst_x, tr->dst_y);
 +	fprintf_ind(file, ind, "ram per frame: %u KiB\n",
 +		    gr_placement_single_frame_ram_size(placement) / 1024);
 +	unsigned ram_size = gr_placement_current_ram_size(placement);
 +	fprintf_ind(file, ind, "ram size: %d KiB\n", ram_size / 1024);
 +}
 +
 +/// Dumps placement pixmaps to `file` with an indentation of `ind` spaces.
 +static void gr_dump_placement_pixmaps(FILE *file, ImagePlacement *placement,
 +				      int ind) {
 +	if (!placement)
 +		return;
 +	int frameidx = 1;
 +	foreach_pixmap(*placement, pixmap, {
 +		fprintf_ind(file, ind, "Frame %d pixmap %lu\n", frameidx,
 +			    pixmap);
 +		++frameidx;
 +	});
 +}
 +
 +/// Dumps the internal state (images and placements) to stderr.
 +void gr_dump_state() {
 +	FILE *file = stderr;
 +	int ind = 0;
 +	fprintf_ind(file, ind, "======= Graphics module state dump =======\n");
 +	fprintf_ind(file, ind,
 +		"sizeof(Image) = %lu  sizeof(ImageFrame) = %lu  "
 +		"sizeof(ImagePlacement) = %lu\n",
 +		sizeof(Image), sizeof(ImageFrame), sizeof(ImagePlacement));
 +	fprintf_ind(file, ind, "Image count: %u\n", kh_size(images));
 +	fprintf_ind(file, ind, "Placement count: %u\n", total_placement_count);
 +	fprintf_ind(file, ind, "Estimated RAM usage: %ld KiB\n",
 +		images_ram_size / 1024);
 +	fprintf_ind(file, ind, "Estimated Disk usage: %ld KiB\n",
 +		images_disk_size / 1024);
 +
 +	Milliseconds now = gr_now_ms();
 +
 +	int64_t images_ram_size_computed = 0;
 +	int64_t images_disk_size_computed = 0;
 +
 +	Image *img = NULL;
 +	ImagePlacement *placement = NULL;
 +	kh_foreach_value(images, img, {
 +		fprintf_ind(file, ind, "----------------\n");
 +		gr_dump_image_info(file, img, 0);
 +		int64_t total_disk_size_computed = 0;
 +		int total_duration_computed = 0;
 +		foreach_frame(*img, frame, {
 +			gr_dump_frame_info(file, frame, 4);
 +			if (frame->image != img)
 +				fprintf_ind(file, 8,
 +					    "ERROR: WRONG IMAGE POINTER\n");
 +			total_duration_computed += frame->gap;
 +			images_disk_size_computed += frame->disk_size;
 +			total_disk_size_computed += frame->disk_size;
 +			if (frame->imlib_object)
 +				images_ram_size_computed +=
 +					gr_frame_current_ram_size(frame);
 +		});
 +		if (img->total_disk_size != total_disk_size_computed) {
 +			fprintf_ind(file, ind,
 +				"    ERROR: total_disk_size is %u, but "
 +				"computed value is %ld\n",
 +				img->total_disk_size, total_disk_size_computed);
 +		}
 +		if (img->total_duration != total_duration_computed) {
 +			fprintf_ind(file, ind,
 +				"    ERROR: total_duration is %d, but computed "
 +				"value is %d\n",
 +				img->total_duration, total_duration_computed);
 +		}
 +		kh_foreach_value(img->placements, placement, {
 +			gr_dump_placement_info(file, placement, 4);
 +			if (placement->image != img)
 +				fprintf_ind(file, 8,
 +					    "ERROR: WRONG IMAGE POINTER\n");
 +			fprintf_ind(file, 8,
 +				    "Pixmaps:\n");
 +			gr_dump_placement_pixmaps(file, placement, 12);
 +			unsigned ram_size =
 +				gr_placement_current_ram_size(placement);
 +			images_ram_size_computed += ram_size;
 +		});
 +	});
 +	if (images_ram_size != images_ram_size_computed) {
 +		fprintf_ind(file, ind,
 +			"ERROR: images_ram_size is %ld, but computed value "
 +			"is %ld\n",
 +			images_ram_size, images_ram_size_computed);
 +	}
 +	if (images_disk_size != images_disk_size_computed) {
 +		fprintf_ind(file, ind,
 +			"ERROR: images_disk_size is %ld, but computed value "
 +			"is %ld\n",
 +			images_disk_size, images_disk_size_computed);
 +	}
 +	fprintf_ind(file, ind, "===========================================\n");
 +}
 +
 +/// Executes `command` with the name of the file corresponding to `image_id` as
 +/// the argument. Executes xmessage with an error message on failure.
 +// TODO: Currently we do this for the first frame only. Not sure what to do with
 +//       animations.
 +void gr_preview_image(uint32_t image_id, const char *exec) {
 +	char command[256];
 +	size_t len;
 +	Image *img = gr_find_image(image_id);
 +	if (img) {
 +		ImageFrame *frame = &img->first_frame;
 +		char filename[MAX_FILENAME_SIZE];
 +		gr_get_frame_filename(frame, filename, MAX_FILENAME_SIZE);
 +		if (frame->disk_size == 0) {
 +			len = snprintf(command, 255,
 +				       "xmessage 'Image with id=%u is not "
 +				       "fully copied to %s'",
 +				       image_id, sanitized_filename(filename));
 +		} else {
 +			len = snprintf(command, 255, "%s %s &", exec,
 +				       sanitized_filename(filename));
 +		}
 +	} else {
 +		len = snprintf(command, 255,
 +			       "xmessage 'Cannot find image with id=%u'",
 +			       image_id);
 +	}
 +	if (len > 255) {
 +		fprintf(stderr, "error: command too long: %s\n", command);
 +		snprintf(command, 255, "xmessage 'error: command too long'");
 +	}
 +	if (system(command) != 0) {
 +		fprintf(stderr, "error: could not execute command %s\n",
 +			command);
 +	}
 +}
 +
 +/// Executes `<st> -e less <file>` where <file> is the name of a temporary file
 +/// containing the information about an image and placement, and <st> is
 +/// specified with `st_executable`.
 +void gr_show_image_info(uint32_t image_id, uint32_t placement_id,
 +			uint32_t imgcol, uint32_t imgrow,
 +			char is_classic_placeholder, int32_t diacritic_count,
 +			char *st_executable) {
 +	char filename[MAX_FILENAME_SIZE];
 +	snprintf(filename, sizeof(filename), "%s/info-%u", cache_dir, image_id);
 +	FILE *file = fopen(filename, "w");
 +	if (!file) {
 +		perror("fopen");
 +		return;
 +	}
 +	// Basic information about the cell.
 +	fprintf(file, "image_id = %u = 0x%08X\n", image_id, image_id);
 +	fprintf(file, "placement_id = %u = 0x%08X\n", placement_id, placement_id);
 +	fprintf(file, "column = %d, row = %d\n", imgcol, imgrow);
 +	fprintf(file, "classic/unicode placeholder = %s\n",
 +		is_classic_placeholder ? "classic" : "unicode");
 +	fprintf(file, "original diacritic count = %d\n", diacritic_count);
 +	// Information about the image and the placement.
 +	Image *img = gr_find_image(image_id);
 +	ImagePlacement *placement = gr_find_placement(img, placement_id);
 +	gr_dump_image_info(file, img, 0);
 +	gr_dump_placement_info(file, placement, 0);
 +	// The text underneath this particular cell.
 +	if (placement && placement->text_underneath && imgcol >= 1 &&
 +	    imgrow >= 1 && imgcol <= placement->cols &&
 +	    imgrow <= placement->rows) {
 +		fprintf(file, "Glyph underneath:\n");
 +		Glyph *glyph =
 +			&placement->text_underneath[(imgrow - 1) *
 +							    placement->cols +
 +						    imgcol - 1];
 +		fprintf(file, "    rune = 0x%08X\n", glyph->u);
 +		fprintf(file, "    bg = 0x%08X\n", glyph->bg);
 +		fprintf(file, "    fg = 0x%08X\n", glyph->fg);
 +		fprintf(file, "    decor = 0x%08X\n", glyph->decor);
 +		fprintf(file, "    mode = 0x%08X\n", glyph->mode);
 +	}
 +	if (img) {
 +		fprintf(file, "Frames:\n");
 +		foreach_frame(*img, frame, {
 +			gr_dump_frame_info(file, frame, 4);
 +		});
 +	}
 +	if (placement) {
 +		fprintf(file, "Placement pixmaps:\n");
 +		gr_dump_placement_pixmaps(file, placement, 4);
 +	}
 +	fclose(file);
 +	char *argv[] = {st_executable, "-e", "less", filename, NULL};
 +	if (posix_spawnp(NULL, st_executable, NULL, NULL, argv, environ) != 0) {
 +		perror("posix_spawnp");
 +		return;
 +	}
 +}
 +
 +////////////////////////////////////////////////////////////////////////////////
 +// Appending and displaying image rectangles.
 +////////////////////////////////////////////////////////////////////////////////
 +
 +/// Displays debug information in the rectangle using colors col1 and col2.
 +static void gr_displayinfo(Drawable buf, ImageRect *rect, int col1, int col2,
 +			   const char *message) {
 +	int w_pix = (rect->img_end_col - rect->img_start_col) * rect->cw;
 +	int h_pix = (rect->img_end_row - rect->img_start_row) * rect->ch;
 +	Display *disp = imlib_context_get_display();
 +	GC gc = XCreateGC(disp, buf, 0, NULL);
 +	char info[MAX_INFO_LEN];
 +	if (rect->placement_id)
 +		snprintf(info, MAX_INFO_LEN, "%s%u/%u [%d:%d)x[%d:%d)", message,
 +			 rect->image_id, rect->placement_id,
 +			 rect->img_start_col, rect->img_end_col,
 +			 rect->img_start_row, rect->img_end_row);
 +	else
 +		snprintf(info, MAX_INFO_LEN, "%s%u [%d:%d)x[%d:%d)", message,
 +			 rect->image_id, rect->img_start_col, rect->img_end_col,
 +			 rect->img_start_row, rect->img_end_row);
 +	XSetForeground(disp, gc, col1);
 +	XDrawString(disp, buf, gc, rect->screen_x_pix + 4,
 +		    rect->screen_y_pix + h_pix - 3, info, strlen(info));
 +	XSetForeground(disp, gc, col2);
 +	XDrawString(disp, buf, gc, rect->screen_x_pix + 2,
 +		    rect->screen_y_pix + h_pix - 5, info, strlen(info));
 +	XFreeGC(disp, gc);
 +}
 +
 +/// Draws a rectangle (bounding box) for debugging.
 +static void gr_showrect(Drawable buf, ImageRect *rect) {
 +	int w_pix = (rect->img_end_col - rect->img_start_col) * rect->cw;
 +	int h_pix = (rect->img_end_row - rect->img_start_row) * rect->ch;
 +	Display *disp = imlib_context_get_display();
 +	GC gc = XCreateGC(disp, buf, 0, NULL);
 +	XSetForeground(disp, gc, 0xFF00FF00);
 +	XDrawRectangle(disp, buf, gc, rect->screen_x_pix, rect->screen_y_pix,
 +		       w_pix - 1, h_pix - 1);
 +	XSetForeground(disp, gc, 0xFFFF0000);
 +	XDrawRectangle(disp, buf, gc, rect->screen_x_pix + 1,
 +		       rect->screen_y_pix + 1, w_pix - 3, h_pix - 3);
 +	XFreeGC(disp, gc);
 +}
 +
 +/// Updates the next redraw time for the given row. Resizes the
 +/// next_redraw_times array if needed.
 +static void gr_update_next_redraw_time(int row, Milliseconds next_redraw) {
 +	if (next_redraw == 0)
 +		return;
 +	if (row >= kv_size(next_redraw_times)) {
 +		size_t old_size = kv_size(next_redraw_times);
 +		kv_a(Milliseconds, next_redraw_times, row);
 +		for (size_t i = old_size; i <= row; ++i)
 +			kv_A(next_redraw_times, i) = 0;
 +	}
 +	Milliseconds old_value = kv_A(next_redraw_times, row);
 +	if (old_value == 0 || old_value > next_redraw)
 +		kv_A(next_redraw_times, row) = next_redraw;
 +}
 +
 +/// Draws the given part of an image.
 +static void gr_drawimagerect(Drawable buf, ImageRect *rect) {
 +	ImagePlacement *placement =
 +		gr_find_image_and_placement(rect->image_id, rect->placement_id);
 +	// If the image does not exist or image display is switched off, draw
 +	// the bounding box.
 +	if (!placement || !graphics_display_images) {
 +		gr_showrect(buf, rect);
 +		if (graphics_debug_mode == GRAPHICS_DEBUG_LOG_AND_BOXES)
 +			gr_displayinfo(buf, rect, 0xFF000000, 0xFFFFFFFF, "");
 +		return;
 +	}
 +
 +	Image *img = placement->image;
 +
 +	if (img->last_redraw < drawing_start_time) {
 +		// This is the first time we draw this image in this redraw
 +		// cycle. Update the frame index we are going to display. Note
 +		// that currently all image placements are synchronized.
 +		int old_frame = img->current_frame;
 +		gr_update_frame_index(img, drawing_start_time);
 +		img->last_redraw = drawing_start_time;
 +	}
 +
 +	// Adjust next redraw times for the rows of this image rect.
 +	if (img->next_redraw) {
 +		for (int row = rect->screen_y_row;
 +		     row <= rect->screen_y_row + rect->img_end_row -
 +					  rect->img_start_row - 1; ++row) {
 +			gr_update_next_redraw_time(
 +				row, img->next_redraw);
 +		}
 +	}
 +
 +	// Load the frame.
 +	Pixmap pixmap = gr_load_pixmap(placement, img->current_frame, rect->cw,
 +				       rect->ch);
 +
 +	// If the image couldn't be loaded, display the bounding box.
 +	if (!pixmap) {
 +		gr_showrect(buf, rect);
 +		if (graphics_debug_mode == GRAPHICS_DEBUG_LOG_AND_BOXES)
 +			gr_displayinfo(buf, rect, 0xFF000000, 0xFFFFFFFF, "");
 +		return;
 +	}
 +
 +	// The coordinates and size (in pixels) of the src rectangle inside the
 +	// box of cells (not the pixmap).
 +	int src_x = rect->img_start_col * rect->cw;
 +	int src_y = rect->img_start_row * rect->ch;
 +	int src_w = (rect->img_end_col - rect->img_start_col) * rect->cw;
 +	int src_h = (rect->img_end_row - rect->img_start_row) * rect->ch;
 +	// The coordinates of the dst rectangle inside the window. The size is
 +	// the same as the src size in the box (src_w, src_h).
 +	int window_x = rect->screen_x_pix;
 +	int window_y = rect->screen_y_pix;
 +
 +	Display *disp = imlib_context_get_display();
 +	Visual *vis = imlib_context_get_visual();
 +
 +	// Create an xrender picture for the window.
 +	XRenderPictFormat *win_format =
 +		XRenderFindVisualFormat(disp, vis);
 +	Picture window_pic =
 +		XRenderCreatePicture(disp, buf, win_format, 0, NULL);
 +
 +	// If needed, invert the image pixmap. Note that this naive approach of
 +	// inverting the pixmap is not entirely correct, because the pixmap is
 +	// premultiplied. But the result is good enough to visually indicate
 +	// selection.
 +	if (rect->reverse) {
 +		unsigned pixmap_w = placement->pixmap_transformation.pixmap_w;
 +		unsigned pixmap_h = placement->pixmap_transformation.pixmap_h;
 +		Pixmap invpixmap =
 +			XCreatePixmap(disp, buf, pixmap_w, pixmap_h, 32);
 +		XGCValues gcv = {.function = GXcopyInverted};
 +		GC gc = XCreateGC(disp, invpixmap, GCFunction, &gcv);
 +		XCopyArea(disp, pixmap, invpixmap, gc, 0, 0, pixmap_w,
 +			  pixmap_h, 0, 0);
 +		XFreeGC(disp, gc);
 +		pixmap = invpixmap;
 +	}
 +
 +	// Create a picture for the image pixmap.
 +	XRenderPictFormat *pic_format =
 +		XRenderFindStandardFormat(disp, PictStandardARGB32);
 +	// We use RepeatPad to avoid bilinear filtering halo.
 +	XRenderPictureAttributes attrs = {0};
 +	attrs.repeat = RepeatPad;
 +	Picture pixmap_pic = XRenderCreatePicture(disp, pixmap, pic_format,
 +						  CPRepeat, &attrs);
 +
 +	// Since the pixmap may be of different size than the destination box of
 +	// cells, we must apply a transformation to it.
 +	// The XTransform structure describes a matrix to transform the
 +	// destination picture coordinates (i.e. in the box) to the source
 +	// coordinates (i.e. in the pixmap). We apply only scaling (translation
 +	// will be applied to the src coordinates directly):
 +	//
 +	//   pixmap_x = picture_x * pixmap_w / dst_w
 +	//   pixmap_y = picture_y * pixmap_h / dst_h
 +	//
 +	// Where dst_w, dst_h, pixmap_w, pixmap_h are from the placement's
 +	// pixmap_transformation structure.
 +	PixmapTransformation *tr = &placement->pixmap_transformation;
 +	double xs = (double)tr->pixmap_w / MAX(tr->dst_w, 1);
 +	double ys = (double)tr->pixmap_h / MAX(tr->dst_h, 1);
 +	// clang-format off
 +	XTransform xform = {{
 +	    { XDoubleToFixed(xs), XDoubleToFixed( 0), XDoubleToFixed( 0) },
 +	    { XDoubleToFixed( 0), XDoubleToFixed(ys), XDoubleToFixed( 0) },
 +	    { XDoubleToFixed( 0), XDoubleToFixed( 0), XDoubleToFixed( 1) }
 +	}};
 +	// clang-format on
 +	XRenderSetPictureTransform(disp, pixmap_pic, &xform);
 +	XRenderSetPictureFilter(disp, pixmap_pic, FilterBilinear, NULL, 0);
 +
 +	// Do the translation: modify the src coordinates to make them
 +	// coordinates into the picture rather than into the box.
 +	src_x -= tr->dst_x;
 +	src_y -= tr->dst_y;
 +	// At this point src_x, src_y, src_w, src_h are coordinates of the
 +	// source rectangle inside the picture (scaled pixmap).
 +
 +	// Now do clipping. If src coordinates are negative, adjust the dst
 +	// coordinates (into the window) and the width/height. We do clipping
 +	// instead of using the values as is to avoid rendering the pad area
 +	// outside the pixmap.
 +	if (src_x < 0) {
 +		window_x += -src_x;
 +		src_w -= -src_x;
 +		src_x = 0;
 +	}
 +	if (src_y < 0) {
 +		window_y += -src_y;
 +		src_h -= -src_y;
 +		src_y = 0;
 +	}
 +
 +	// Adjust width and height if the src rectangle exceeds the picture.
 +	src_w = MIN(src_w, tr->dst_w - src_x);
 +	src_h = MIN(src_h, tr->dst_h - src_y);
 +
 +	// Composite the image onto the window. In the reverse mode we ignore
 +	// the alpha channel of the image because the naive inversion above
 +	// seems to invert the alpha channel as well.
 +	int pictop = rect->reverse ? PictOpSrc : PictOpOver;
 +	if (src_w > 0 && src_h > 0)
 +		XRenderComposite(disp, pictop, pixmap_pic, 0, window_pic, src_x,
 +				 src_y, src_x, src_y, window_x, window_y, src_w,
 +				 src_h);
 +
 +	// Free resources
 +	XRenderFreePicture(disp, pixmap_pic);
 +	XRenderFreePicture(disp, window_pic);
 +	if (rect->reverse)
 +		XFreePixmap(disp, pixmap);
 +
 +	// In debug mode always draw bounding boxes and print info.
 +	if (graphics_debug_mode == GRAPHICS_DEBUG_LOG_AND_BOXES) {
 +		gr_showrect(buf, rect);
 +		gr_displayinfo(buf, rect, 0xFF000000, 0xFFFFFFFF, "");
 +	}
 +}
 +
 +/// Removes the given image rectangle.
 +static void gr_freerect(ImageRect *rect) { memset(rect, 0, sizeof(ImageRect)); }
 +
 +/// Returns the bottom coordinate of the rect.
 +static int gr_getrectbottom(ImageRect *rect) {
 +	return rect->screen_y_pix +
 +	       (rect->img_end_row - rect->img_start_row) * rect->ch;
 +}
 +
 +/// Prepare for image drawing. `cw` and `ch` are dimensions of the cell.
 +void gr_start_drawing(Drawable buf, int cw, int ch) {
 +	current_cw = cw;
 +	current_ch = ch;
 +	debug_loaded_files_counter = 0;
 +	debug_loaded_pixmaps_counter = 0;
 +	drawing_start_time = gr_now_ms();
 +	imlib_context_set_drawable(buf);
 +}
 +
 +/// Finish image drawing. This functions will draw all the rectangles left to
 +/// draw.
 +void gr_finish_drawing(Drawable buf) {
 +	// Draw and then delete all known image rectangles.
 +	for (size_t i = 0; i < MAX_IMAGE_RECTS; ++i) {
 +		ImageRect *rect = &image_rects[i];
 +		if (!rect->image_id)
 +			continue;
 +		gr_drawimagerect(buf, rect);
 +		gr_freerect(rect);
 +	}
 +
 +	// Compute the delay until the next redraw as the minimum of the next
 +	// redraw delays for all rows.
 +	Milliseconds drawing_end_time = gr_now_ms();
 +	graphics_next_redraw_delay = INT_MAX;
 +	for (int row = 0; row < kv_size(next_redraw_times); ++row) {
 +		Milliseconds row_next_redraw = kv_A(next_redraw_times, row);
 +		if (row_next_redraw > 0) {
 +			int delay = MAX(graphics_animation_min_delay,
 +					row_next_redraw - drawing_end_time);
 +			graphics_next_redraw_delay =
 +				MIN(graphics_next_redraw_delay, delay);
 +		}
 +	}
 +
 +	// In debug mode display additional info.
 +	if (graphics_debug_mode) {
 +		int milliseconds = drawing_end_time - drawing_start_time;
 +
 +		Display *disp = imlib_context_get_display();
 +		GC gc = XCreateGC(disp, buf, 0, NULL);
 +		const char *debug_mode_str =
 +			graphics_debug_mode == GRAPHICS_DEBUG_LOG_AND_BOXES
 +				? "(boxes shown) "
 +				: "";
 +		int redraw_delay = graphics_next_redraw_delay == INT_MAX
 +					   ? -1
 +					   : graphics_next_redraw_delay;
 +		char info[MAX_INFO_LEN];
 +		snprintf(info, MAX_INFO_LEN,
 +			 "%sRender time: %d ms  ram %ld K  disk %ld K  count "
 +			 "%d  cell %dx%d  delay %d",
 +			 debug_mode_str, milliseconds, images_ram_size / 1024,
 +			 images_disk_size / 1024, kh_size(images), current_cw,
 +			 current_ch, redraw_delay);
 +		XSetForeground(disp, gc, 0xFF000000);
 +		XFillRectangle(disp, buf, gc, 0, 0, 600, 16);
 +		XSetForeground(disp, gc, 0xFFFFFFFF);
 +		XDrawString(disp, buf, gc, 0, 14, info, strlen(info));
 +		XFreeGC(disp, gc);
 +
 +		if (milliseconds > 0) {
 +			fprintf(stderr, "%s  (loaded %d files, %d pixmaps)\n",
 +				info, debug_loaded_files_counter,
 +				debug_loaded_pixmaps_counter);
 +		}
 +	}
 +
 +	// Check the limits in case we have used too much ram for placements.
 +	gr_check_limits();
 +}
 +
 +// Add an image rectangle to the list of rectangles to draw.
 +void gr_append_imagerect(Drawable buf, uint32_t image_id, uint32_t placement_id,
 +			 int img_start_col, int img_end_col, int img_start_row,
 +			 int img_end_row, int x_col, int y_row, int x_pix,
 +			 int y_pix, int cw, int ch, int reverse) {
 +	current_cw = cw;
 +	current_ch = ch;
 +
 +	ImageRect new_rect;
 +	new_rect.image_id = image_id;
 +	new_rect.placement_id = placement_id;
 +	new_rect.img_start_col = img_start_col;
 +	new_rect.img_end_col = img_end_col;
 +	new_rect.img_start_row = img_start_row;
 +	new_rect.img_end_row = img_end_row;
 +	new_rect.screen_y_row = y_row;
 +	new_rect.screen_x_pix = x_pix;
 +	new_rect.screen_y_pix = y_pix;
 +	new_rect.ch = ch;
 +	new_rect.cw = cw;
 +	new_rect.reverse = reverse;
 +
 +	// Display some red text in debug mode.
 +	if (graphics_debug_mode == GRAPHICS_DEBUG_LOG_AND_BOXES)
 +		gr_displayinfo(buf, &new_rect, 0xFF000000, 0xFFFF0000, "? ");
 +
 +	// If it's the empty image (image_id=0) or an empty rectangle, do
 +	// nothing.
 +	if (image_id == 0 || img_end_col - img_start_col <= 0 ||
 +	    img_end_row - img_start_row <= 0)
 +		return;
 +	// Try to find a rect to merge with.
 +	ImageRect *free_rect = NULL;
 +	for (size_t i = 0; i < MAX_IMAGE_RECTS; ++i) {
 +		ImageRect *rect = &image_rects[i];
 +		if (rect->image_id == 0) {
 +			if (!free_rect)
 +				free_rect = rect;
 +			continue;
 +		}
 +		if (rect->image_id != image_id ||
 +		    rect->placement_id != placement_id || rect->cw != cw ||
 +		    rect->ch != ch || rect->reverse != reverse)
 +			continue;
 +		// We only support the case when the new stripe is added to the
 +		// bottom of an existing rectangle and they are perfectly
 +		// aligned.
 +		if (rect->img_end_row == img_start_row &&
 +		    gr_getrectbottom(rect) == y_pix) {
 +			if (rect->img_start_col == img_start_col &&
 +			    rect->img_end_col == img_end_col &&
 +			    rect->screen_x_pix == x_pix) {
 +				rect->img_end_row = img_end_row;
 +				return;
 +			}
 +		}
 +	}
 +	// If we haven't merged the new rect with any existing rect, and there
 +	// is no free rect, we have to render one of the existing rects.
 +	if (!free_rect) {
 +		for (size_t i = 0; i < MAX_IMAGE_RECTS; ++i) {
 +			ImageRect *rect = &image_rects[i];
 +			if (!free_rect || gr_getrectbottom(free_rect) >
 +						  gr_getrectbottom(rect))
 +				free_rect = rect;
 +		}
 +		gr_drawimagerect(buf, free_rect);
 +		gr_freerect(free_rect);
 +	}
 +	// Start a new rectangle in `free_rect`.
 +	*free_rect = new_rect;
 +}
 +
 +/// Mark rows containing animations as dirty if it's time to redraw them. Must
 +/// be called right after `gr_start_drawing`.
 +void gr_mark_dirty_animations(int *dirty, int rows) {
 +	if (rows < kv_size(next_redraw_times))
 +		kv_size(next_redraw_times) = rows;
 +	if (rows * 2 < kv_max(next_redraw_times))
 +		kv_resize(Milliseconds, next_redraw_times, rows);
 +	for (int i = 0; i < MIN(rows, kv_size(next_redraw_times)); ++i) {
 +		if (dirty[i]) {
 +			kv_A(next_redraw_times, i) = 0;
 +			continue;
 +		}
 +		Milliseconds next_update = kv_A(next_redraw_times, i);
 +		if (next_update > 0 && next_update <= drawing_start_time) {
 +			dirty[i] = 1;
 +			kv_A(next_redraw_times, i) = 0;
 +		}
 +	}
 +}
 +
 +////////////////////////////////////////////////////////////////////////////////
 +// Command parsing and handling.
 +////////////////////////////////////////////////////////////////////////////////
 +
 +/// A parsed kitty graphics protocol command.
 +typedef struct {
 +	/// The command itself, without the 'G'.
 +	char *command;
 +	/// The payload (after ';').
 +	char *payload;
 +	/// 'a=', may be 't', 'q', 'f', 'T', 'p', 'd', 'a'.
 +	char action;
 +	/// 'q=', 1 to suppress OK response, 2 to suppress errors too.
 +	int quiet;
 +	/// 'f=', use 24 or 32 for raw pixel data, 100 to autodetect with
 +	/// imlib2. If 'f=0', will try to load with imlib2, then fallback to
 +	/// 32-bit pixel data.
 +	int format;
 +	/// 'o=', may be 'z' for RFC 1950 ZLIB.
 +	int compression;
 +	/// 't=', may be 'f', 't' or 'd'.
 +	char transmission_medium;
 +	/// 'd='
 +	char delete_specifier;
 +	/// 's=', 'v=', if 'a=t' or 'a=T', used only when 'f=24' or 'f=32'.
 +	/// When 'a=f', this is the size of the frame rectangle when composed on
 +	/// top of another frame.
 +	int frame_pix_width, frame_pix_height;
 +	/// 'x=', 'y=' - top-left corner of the source rectangle.
 +	int src_pix_x, src_pix_y;
 +	/// 'w=', 'h=' - width and height of the source rectangle.
 +	int src_pix_width, src_pix_height;
 +	/// 'r=', 'c='
 +	int rows, columns;
 +	/// 'i='
 +	uint32_t image_id;
 +	/// 'I='
 +	uint32_t image_number;
 +	/// 'p='
 +	uint32_t placement_id;
 +	/// 'm=', may be 0 or 1.
 +	int more;
 +	/// True if turns out that this command is a continuation of a data
 +	/// transmission and not the first one for this image. Populated by
 +	/// `gr_handle_transmit_command`.
 +	char is_direct_transmission_continuation;
 +	/// 'S=', used to check the size of uploaded data.
 +	int size;
 +	/// The offset of the frame image data in the shared memory ('O=').
 +	unsigned offset;
 +	/// 'U=', whether it's a virtual placement for Unicode placeholders.
 +	int virtual;
 +	/// 'C=', if true, do not move the cursor when displaying this placement
 +	/// (non-virtual placements only).
 +	char do_not_move_cursor;
 +	// ---------------------------------------------------------------------
 +	// Animation-related fields. Their keys often overlap with keys of other
 +	// commands, so these make sense only if the action is 'a=f' (frame
 +	// transmission) or 'a=a' (animation control).
 +	//
 +	// 'x=' and 'y=', the relative position of the frame image when it's
 +	// composed on top of another frame.
 +	int frame_dst_pix_x, frame_dst_pix_y;
 +	/// 'X=', 'X=1' to replace colors instead of alpha blending on top of
 +	/// the background color or frame.
 +	char replace_instead_of_blending;
 +	/// 'Y=', the background color in the 0xRRGGBBAA format (still
 +	/// transmitted as a decimal number).
 +	uint32_t background_color;
 +	/// (Only for 'a=f'). 'c=', the 1-based index of the background frame.
 +	int background_frame;
 +	/// (Only for 'a=a'). 'c=', sets the index of the current frame.
 +	int current_frame;
 +	/// 'r=', the 1-based index of the frame to edit.
 +	int edit_frame;
 +	/// 'z=', the duration of the frame. Zero if not specified, negative if
 +	/// the frame is gapless (i.e. skipped).
 +	int gap;
 +	/// (Only for 'a=a'). 's=', if non-zero, sets the state of the
 +	/// animation, 1 to stop, 2 to run in loading mode, 3 to loop.
 +	int animation_state;
 +	/// (Only for 'a=a'). 'v=', if non-zero, sets the number of times the
 +	/// animation will loop. 1 to loop infinitely, N to loop N-1 times.
 +	int loops;
 +} GraphicsCommand;
 +
 +/// Replaces all non-printed characters in `str` with '?' and truncates the
 +/// string to `max_size`, maybe inserting ellipsis at the end.
 +static void sanitize_str(char *str, size_t max_size) {
 +	assert(max_size >= 4);
 +	for (size_t i = 0; i < max_size; ++i) {
 +		unsigned c = str[i];
 +		if (c == '\0')
 +			return;
 +		if (c >= 128 || !isprint(c))
 +			str[i] = '?';
 +	}
 +	str[max_size - 1] = '\0';
 +	str[max_size - 2] = '.';
 +	str[max_size - 3] = '.';
 +	str[max_size - 4] = '.';
 +}
 +
 +/// A non-destructive version of `sanitize_str`. Uses a static buffer, so be
 +/// careful.
 +static const char *sanitized_filename(const char *str) {
 +	static char buf[MAX_FILENAME_SIZE];
 +	strncpy(buf, str, sizeof(buf));
 +	sanitize_str(buf, sizeof(buf));
 +	return buf;
 +}
 +
 +/// Creates a response to the current command in `graphics_command_result`.
 +static void gr_createresponse(uint32_t image_id, uint32_t image_number,
 +			      uint32_t placement_id, const char *msg) {
 +	if (!image_id && !image_number && !placement_id) {
 +		// Nobody expects the response in this case, so just print it to
 +		// stderr.
 +		fprintf(stderr,
 +			"error: No image id or image number or placement_id, "
 +			"but still there is a response: %s\n",
 +			msg);
 +		return;
 +	}
 +	char *buf = graphics_command_result.response;
 +	size_t maxlen = MAX_GRAPHICS_RESPONSE_LEN;
 +	size_t written;
 +	written = snprintf(buf, maxlen, "\033_G");
 +	buf += written;
 +	maxlen -= written;
 +	if (image_id) {
 +		written = snprintf(buf, maxlen, "i=%u,", image_id);
 +		buf += written;
 +		maxlen -= written;
 +	}
 +	if (image_number) {
 +		written = snprintf(buf, maxlen, "I=%u,", image_number);
 +		buf += written;
 +		maxlen -= written;
 +	}
 +	if (placement_id) {
 +		written = snprintf(buf, maxlen, "p=%u,", placement_id);
 +		buf += written;
 +		maxlen -= written;
 +	}
 +	buf[-1] = ';';
 +	written = snprintf(buf, maxlen, "%s\033\\", msg);
 +	buf += written;
 +	maxlen -= written;
 +	buf[-2] = '\033';
 +	buf[-1] = '\\';
 +}
 +
 +/// Creates the 'OK' response to the current command, unless suppressed or a
 +/// non-final data transmission.
 +static void gr_reportsuccess_cmd(GraphicsCommand *cmd) {
 +	if (cmd->quiet < 1 && !cmd->more)
 +		gr_createresponse(cmd->image_id, cmd->image_number,
 +				  cmd->placement_id, "OK");
 +}
 +
 +/// Creates the 'OK' response to the current command (unless suppressed).
 +static void gr_reportsuccess_frame(ImageFrame *frame) {
 +	uint32_t id = frame->image->query_id ? frame->image->query_id
 +					     : frame->image->image_id;
 +	if (frame->quiet < 1)
 +		gr_createresponse(id, frame->image->image_number,
 +				  frame->image->initial_placement_id, "OK");
 +}
 +
 +/// Creates an error response to the current command (unless suppressed).
 +static void gr_reporterror_cmd(GraphicsCommand *cmd, const char *format, ...) {
 +	char errmsg[MAX_GRAPHICS_RESPONSE_LEN];
 +	graphics_command_result.error = 1;
 +	va_list args;
 +	va_start(args, format);
 +	vsnprintf(errmsg, MAX_GRAPHICS_RESPONSE_LEN, format, args);
 +	va_end(args);
 +
 +	fprintf(stderr, "%s  in command: %s\n", errmsg, cmd->command);
 +	if (cmd->quiet < 2)
 +		gr_createresponse(cmd->image_id, cmd->image_number,
 +				  cmd->placement_id, errmsg);
 +}
 +
 +/// Creates an error response to the current command (unless suppressed).
 +static void gr_reporterror_frame(ImageFrame *frame, const char *format, ...) {
 +	char errmsg[MAX_GRAPHICS_RESPONSE_LEN];
 +	graphics_command_result.error = 1;
 +	va_list args;
 +	va_start(args, format);
 +	vsnprintf(errmsg, MAX_GRAPHICS_RESPONSE_LEN, format, args);
 +	va_end(args);
 +
 +	if (!frame) {
 +		fprintf(stderr, "%s\n", errmsg);
 +		gr_createresponse(0, 0, 0, errmsg);
 +	} else {
 +		uint32_t id = frame->image->query_id ? frame->image->query_id
 +						     : frame->image->image_id;
 +		fprintf(stderr, "%s  id=%u\n", errmsg, id);
 +		if (frame->quiet < 2)
 +			gr_createresponse(id, frame->image->image_number,
 +					  frame->image->initial_placement_id,
 +					  errmsg);
 +	}
 +}
 +
 +/// Loads an image and creates a success/failure response. Returns `frame`, or
 +/// NULL if it's a query action and the image was deleted.
 +static ImageFrame *gr_loadimage_and_report(ImageFrame *frame) {
 +	gr_load_imlib_object(frame);
 +	if (!frame->imlib_object) {
 +		gr_reporterror_frame(frame, "EBADF: could not load image");
 +	} else {
 +		gr_reportsuccess_frame(frame);
 +	}
 +	// If it was a query action, discard the image.
 +	if (frame->image->query_id) {
 +		gr_delete_image(frame->image);
 +		return NULL;
 +	}
 +	return frame;
 +}
 +
 +/// Creates an appropriate uploading failure response to the current command.
 +static void gr_reportuploaderror(ImageFrame *frame) {
 +	switch (frame->uploading_failure) {
 +	case 0:
 +		return;
 +	case ERROR_CANNOT_OPEN_CACHED_FILE:
 +		gr_reporterror_frame(frame,
 +				   "EIO: could not create a file for image");
 +		break;
 +	case ERROR_OVER_SIZE_LIMIT:
 +		gr_reporterror_frame(
 +			frame,
 +			"EFBIG: the size of the uploaded image exceeded "
 +			"the image size limit %u",
 +			graphics_max_single_image_file_size);
 +		break;
 +	case ERROR_UNEXPECTED_SIZE:
 +		gr_reporterror_frame(frame,
 +				   "EINVAL: the size of the uploaded image %u "
 +				   "doesn't match the expected size %u",
 +				   frame->disk_size, frame->expected_size);
 +		break;
 +	};
 +}
 +
 +/// Displays a non-virtual placement. This functions records the information in
 +/// `graphics_command_result`, the placeholder itself is created by the terminal
 +/// after handling the current command in the graphics module.
 +static void gr_display_nonvirtual_placement(ImagePlacement *placement) {
 +	if (placement->virtual)
 +		return;
 +	if (placement->image->first_frame.status < STATUS_RAM_LOADING_SUCCESS)
 +		return;
 +	// Infer the placement size if needed.
 +	gr_infer_placement_size_maybe(placement);
 +	// Populate the information about the placeholder which will be created
 +	// by the terminal.
 +	graphics_command_result.create_placeholder = 1;
 +	graphics_command_result.placeholder.image_id = placement->image->image_id;
 +	graphics_command_result.placeholder.placement_id = placement->placement_id;
 +	graphics_command_result.placeholder.columns = placement->cols;
 +	graphics_command_result.placeholder.rows = placement->rows;
 +	graphics_command_result.placeholder.do_not_move_cursor =
 +		placement->do_not_move_cursor;
 +	placement->text_underneath =
 +		calloc(placement->rows * placement->cols, sizeof(Glyph));
 +	graphics_command_result.placeholder.text_underneath =
 +		placement->text_underneath;
 +	GR_LOG("Creating a placeholder for %u/%u  %d x %d\n",
 +	       placement->image->image_id, placement->placement_id,
 +	       placement->cols, placement->rows);
 +}
 +
 +/// Marks the rows that are occupied by the image as dirty.
 +static void gr_schedule_image_redraw(Image *img) {
 +	if (!img)
 +		return;
 +	gr_schedule_image_redraw_by_id(img->image_id);
 +}
 +
 +/// Closes the file currently being uploaded. This doesn't necessarily finish
 +/// the upload since the file may be reopened.
 +static void gr_close_current_upload_file() {
 +	Image *img = gr_find_image(current_upload_image_id);
 +	ImageFrame *frame = gr_get_frame(img, current_upload_frame_index);
 +	gr_close_disk_cache_file(frame);
 +}
 +
 +/// Sets the current image and frame being uploaded. Closes the previous upload
 +/// file if it's changed. If `frame` is NULL, clears the current upload
 +/// image/frame.
 +static void gr_set_current_upload_frame(ImageFrame *frame) {
 +	if (frame) {
 +		if (current_upload_image_id != frame->image->image_id ||
 +		    current_upload_frame_index != frame->index) {
 +			gr_close_current_upload_file();
 +		}
 +		current_upload_image_id = frame->image->image_id;
 +		current_upload_frame_index = frame->index;
 +		GR_LOG("Set current_upload_image_id = %u, "
 +		       "current_upload_frame_index = %u\n",
 +		       current_upload_image_id, current_upload_frame_index);
 +	} else {
 +		gr_close_current_upload_file();
 +		current_upload_image_id = 0;
 +		current_upload_frame_index = 0;
 +		GR_LOG("Set current_upload_image_id = 0\n");
 +	}
 +}
 +
 +/// Returns whether direct transmission continuation is allowed for the given
 +/// command and frame.
 +static int gr_transmission_continuation_is_allowed(GraphicsCommand *cmd,
 +						   ImageFrame *frame) {
 +	if (!frame || frame->status != STATUS_UPLOADING)
 +		return 0;
 +
 +	// If it's the same image and frame as the current upload, allow it.
 +	if (current_upload_image_id == frame->image->image_id &&
 +	    current_upload_frame_index == frame->index)
 +		return 1;
 +
 +	// Otherwise it's a continuation of an interrupted upload. The kitty
 +	// graphics protocol doesn't allow interleaving of direct transmission
 +	// with other commands, so interrupted uploads must be aborted. However,
 +	// we still allow it as an extension, because it's useful for
 +	// protocol-unaware multiplexer. We check that there are no
 +	// contradictions, and the time since the last upload activity is small.
 +
 +	if (cmd->size && cmd->size != frame->expected_size) {
 +		fprintf(stderr, "warning: Not resuming interrupted upload "
 +				"because of expected size mismatch\n");
 +		return 0;
 +	}
 +	if (cmd->format && cmd->format != frame->format) {
 +		fprintf(stderr, "warning: Not resuming interrupted upload "
 +				"because of format mismatch\n");
 +		return 0;
 +	}
 +	if (cmd->compression && cmd->compression != frame->compression) {
 +		fprintf(stderr, "warning: Not resuming interrupted upload "
 +				"because of compression mismatch\n");
 +		return 0;
 +	}
 +	if ((cmd->frame_pix_width &&
 +	     cmd->frame_pix_width != frame->data_pix_width) ||
 +	    (cmd->frame_pix_height &&
 +	     cmd->frame_pix_height != frame->data_pix_height) ||
 +	    (cmd->background_color &&
 +	     cmd->background_color != frame->background_color) ||
 +	    (cmd->background_frame &&
 +	     cmd->background_frame != frame->background_frame_index) ||
 +	    (cmd->gap && cmd->gap != frame->gap) ||
 +	    (cmd->replace_instead_of_blending &&
 +	     cmd->replace_instead_of_blending != !frame->blend)) {
 +		fprintf(stderr, "warning: Not resuming interrupted upload "
 +				"because of frame parameters mismatch\n");
 +		return 0;
 +	}
 +
 +	Milliseconds now = gr_now_ms();
 +	if (now - frame->atime > graphics_direct_transmission_timeout_ms) {
 +		fprintf(stderr, "warning: Not resuming interrupted upload "
 +				"because of time out\n");
 +		return 0;
 +	}
 +
 +	return 1;
 +}
 +
 +/// Appends `data` to the on-disk cache file of the frame `frame`. Creates the
 +/// file if it doesn't exist. Updates `frame->disk_size` and the total disk
 +/// size. Returns 1 on success and 0 on failure.
 +static int gr_append_raw_data_to_file(ImageFrame *frame, const char *data,
 +				      size_t data_size) {
 +	// If there is no open file corresponding to the image, create it.
 +	if (!frame->open_file) {
 +		gr_make_sure_tmpdir_exists();
 +		char filename[MAX_FILENAME_SIZE];
 +		gr_get_frame_filename(frame, filename, MAX_FILENAME_SIZE);
 +		FILE *file = fopen(filename, frame->disk_size ? "a" : "w");
 +		if (!file)
 +			return 0;
 +		frame->open_file = file;
 +	}
 +
 +	// Write data to the file and update disk size variables.
 +	fwrite(data, 1, data_size, frame->open_file);
 +	frame->disk_size += data_size;
 +	frame->image->total_disk_size += data_size;
 +	images_disk_size += data_size;
 +	gr_touch_frame(frame);
 +	return 1;
 +}
 +
 +/// Appends data from `payload` to the frame `frame` when using direct
 +/// transmission. Note that we report errors only for the final command
 +/// (`!more`) to avoid spamming the client. If the frame is not specified, use
 +/// the image id and frame index we are currently uploading.
 +static void gr_append_data(ImageFrame *frame, const char *payload, int more) {
 +	gr_set_current_upload_frame(frame);
 +
 +	if (frame->status != STATUS_UPLOADING) {
 +		if (!more)
 +			gr_reportuploaderror(frame);
 +		gr_set_current_upload_frame(NULL);
 +		return;
 +	}
 +
 +	// Decode the data.
 +	size_t data_size = 0;
 +	char *data = gr_base64dec(payload, &data_size);
 +
 +	GR_LOG("appending %u + %zu = %zu bytes\n", frame->disk_size, data_size,
 +	       frame->disk_size + data_size);
 +
 +	// Do not append this data if the image exceeds the size limit.
 +	if (frame->disk_size + data_size >
 +		    graphics_max_single_image_file_size ||
 +	    frame->expected_size > graphics_max_single_image_file_size) {
 +		free(data);
 +		gr_delete_imagefile(frame);
 +		frame->uploading_failure = ERROR_OVER_SIZE_LIMIT;
 +		if (!more)
 +			gr_reportuploaderror(frame);
 +		gr_set_current_upload_frame(NULL);
 +		return;
 +	}
 +
 +	// Append the data to the file.
 +	if (!gr_append_raw_data_to_file(frame, data, data_size)) {
 +		frame->status = STATUS_UPLOADING_ERROR;
 +		frame->uploading_failure = ERROR_CANNOT_OPEN_CACHED_FILE;
 +		if (!more)
 +			gr_reportuploaderror(frame);
 +		gr_set_current_upload_frame(NULL);
 +		return;
 +	}
 +	free(data);
 +
 +	if (!more) {
 +		gr_set_current_upload_frame(NULL);
 +		frame->status = STATUS_UPLOADING_SUCCESS;
 +		uint32_t placement_id = frame->image->default_placement;
 +		if (frame->expected_size &&
 +		    frame->expected_size != frame->disk_size) {
 +			// Report failure if the uploaded image size doesn't
 +			// match the expected size.
 +			frame->status = STATUS_UPLOADING_ERROR;
 +			frame->uploading_failure = ERROR_UNEXPECTED_SIZE;
 +			gr_reportuploaderror(frame);
 +		} else {
 +			// Make sure to redraw all existing image instances.
 +			gr_schedule_image_redraw(frame->image);
 +			// Try to load the image into ram and report the result.
 +			frame = gr_loadimage_and_report(frame);
 +			// If there is a non-virtual image placement, we may
 +			// need to display it.
 +			if (frame && frame->index == 1) {
 +				Image *img = frame->image;
 +				ImagePlacement *placement = NULL;
 +				kh_foreach_value(img->placements, placement, {
 +					gr_display_nonvirtual_placement(placement);
 +				});
 +			}
 +		}
 +	}
 +
 +	// Check whether we need to delete old images.
 +	gr_check_limits();
 +}
 +
 +/// Finds the image either by id or by number specified in the command.
 +static Image *gr_find_image_for_command(GraphicsCommand *cmd) {
 +	if (cmd->image_id)
 +		return gr_find_image(cmd->image_id);
 +	Image *img = NULL;
 +	// If the image number is not specified, we can't find the image, unless
 +	// it's a put command, in which case we will try the last image.
 +	if (cmd->image_number == 0 && cmd->action == 'p')
 +		img = gr_find_image(last_image_id);
 +	else
 +		img = gr_find_image_by_number(cmd->image_number);
 +	return img;
 +}
 +
 +/// Creates a new image or a new frame in an existing image (depending on the
 +/// command's action) and initializes its parameters from the command.
 +static ImageFrame *gr_new_image_or_frame_from_command(GraphicsCommand *cmd) {
 +	if (cmd->format != 0 && cmd->format != 32 && cmd->format != 24 &&
 +	    cmd->compression != 0) {
 +		gr_reporterror_cmd(cmd, "EINVAL: compression is supported only "
 +					"for raw pixel data (f=32 or f=24)");
 +		// Even though we report an error, we still create an image.
 +	}
 +
 +	Image *img = NULL;
 +	if (cmd->action == 'f') {
 +		// If it's a frame transmission action, there must be an
 +		// existing image.
 +		img = gr_find_image_for_command(cmd);
 +		if (img) {
 +			cmd->image_id = img->image_id;
 +		} else {
 +			gr_reporterror_cmd(cmd, "ENOENT: image not found");
 +			return NULL;
 +		}
 +	} else {
 +		// Otherwise create a new image object. If the action is `q`,
 +		// we'll use random id instead of the one specified in the
 +		// command.
 +		uint32_t image_id = cmd->action == 'q' ? 0 : cmd->image_id;
 +		img = gr_new_image(image_id);
 +		if (!img)
 +			return NULL;
 +		if (cmd->action == 'q')
 +			img->query_id = cmd->image_id;
 +		else if (!cmd->image_id)
 +			cmd->image_id = img->image_id;
 +		// Set the image number.
 +		img->image_number = cmd->image_number;
 +	}
 +
 +	ImageFrame *frame = gr_append_new_frame(img);
 +	// Initialize the frame.
 +	frame->expected_size = cmd->size;
 +	// The default format is 32.
 +	frame->format = cmd->format ? cmd->format : 32;
 +	frame->compression = cmd->compression;
 +	frame->background_color = cmd->background_color;
 +	frame->background_frame_index = cmd->background_frame;
 +	frame->gap = cmd->gap;
 +	img->total_duration += frame->gap;
 +	frame->blend = !cmd->replace_instead_of_blending;
 +	frame->data_pix_width = cmd->frame_pix_width;
 +	frame->data_pix_height = cmd->frame_pix_height;
 +	if (cmd->action == 'f') {
 +		frame->x = cmd->frame_dst_pix_x;
 +		frame->y = cmd->frame_dst_pix_y;
 +	}
 +	// If the expected size is not specified, we can infer it from the pixel
 +	// width and height if the format is 24 or 32 and there is no
 +	// compression. This is required for the shared memory transmission.
 +	if (!frame->expected_size && !frame->compression &&
 +	    (frame->format == 24 || frame->format == 32)) {
 +		frame->expected_size = frame->data_pix_width *
 +				       frame->data_pix_height *
 +				       (frame->format / 8);
 +	}
 +	// We save the quietness information in the frame because for direct
 +	// transmission subsequent transmission command won't contain this info.
 +	frame->quiet = cmd->quiet;
 +	return frame;
 +}
 +
 +/// Removes a file if it actually looks like a temporary file.
 +static void gr_delete_tmp_file(const char *filename) {
 +	if (strstr(filename, "tty-graphics-protocol") == NULL)
 +		return;
 +	if (strstr(filename, "/tmp/") != filename) {
 +		const char *tmpdir = getenv("TMPDIR");
 +		if (!tmpdir || !tmpdir[0] ||
 +		    strstr(filename, tmpdir) != filename)
 +			return;
 +	}
 +	unlink(filename);
 +}
 +
 +/// Copy the image file `frame->original_filename` to the cache directory. This
 +/// is done when the image is transmitted via file transfer, or when we have
 +/// evicted the image from the disk cache and need to restore it.
 +/// If `cmd` is not NULL, it's used to report errors, otherwise errors are only
 +/// printed to stderr.
 +static void gr_copy_imagefile(ImageFrame *frame, GraphicsCommand *cmd) {
 +	GR_LOG("Copying image %s\n",
 +	       sanitized_filename(frame->original_filename));
 +	// Stat the file and check that it's a regular file and not too big.
 +	struct stat st;
 +	int stat_res = stat(frame->original_filename, &st);
 +
 +	const char *stat_error = NULL;
 +	if (stat_res)
 +		stat_error = strerror(errno);
 +	else if (!S_ISREG(st.st_mode))
 +		stat_error = "Not a regular file";
 +	else if (st.st_size == 0)
 +		stat_error = "The size of the file is zero";
 +	else if (st.st_size > graphics_max_single_image_file_size)
 +		stat_error = "The file is too large";
 +	if (stat_error) {
 +		fprintf(stderr, "Could not load the file %s: %s\n",
 +			sanitized_filename(frame->original_filename),
 +			stat_error);
 +		if (cmd)
 +			gr_reporterror_cmd(cmd, "EBADF: %s", stat_error);
 +		frame->status = STATUS_UPLOADING_ERROR;
 +		frame->uploading_failure = ERROR_CANNOT_COPY_FILE;
 +		return;
 +	}
 +
 +	// Check the expected size if specified.
 +	if (frame->expected_size && frame->expected_size != st.st_size) {
 +		fprintf(stderr,
 +			"Could not load, the size doesn't match: %s expected "
 +			"%u vs actual %ld\n",
 +			sanitized_filename(frame->original_filename),
 +			frame->expected_size, st.st_size);
 +		// The file has unexpected size.
 +		frame->status = STATUS_UPLOADING_ERROR;
 +		frame->uploading_failure = ERROR_UNEXPECTED_SIZE;
 +		if (cmd)
 +			gr_reportuploaderror(frame);
 +		return;
 +	}
 +
 +	// If we know the original modification time, we are trying to restore
 +	// the evicted image file. Check that the modification time matches.
 +	if (frame->original_file_mtime &&
 +	    frame->original_file_mtime != st.st_mtime) {
 +		fprintf(stderr, "Could not load, the mtime doesn't match: %s\n",
 +			sanitized_filename(frame->original_filename));
 +		frame->status = STATUS_UPLOADING_ERROR;
 +		frame->uploading_failure = ERROR_MTIME_MISMATCH;
 +		if (cmd)
 +			gr_reportuploaderror(frame);
 +		return;
 +	}
 +
 +	frame->original_file_mtime = st.st_mtime;
 +
 +	gr_make_sure_tmpdir_exists();
 +	// Build the filename for the cached copy of the file.
 +	char cache_filename[MAX_FILENAME_SIZE];
 +	gr_get_frame_filename(frame, cache_filename, MAX_FILENAME_SIZE);
 +	// We will create a symlink to the original file, and
 +	// then copy the file to the temporary cache dir. We do
 +	// this symlink trick mostly to be able to use cp for
 +	// copying, and avoid escaping file name characters when
 +	// calling system at the same time.
 +	char tmp_filename_symlink[MAX_FILENAME_SIZE + 4] = {0};
 +	strcat(tmp_filename_symlink, cache_filename);
 +	strcat(tmp_filename_symlink, ".sym");
 +	char command[MAX_FILENAME_SIZE + 256];
 +	size_t len = snprintf(command, MAX_FILENAME_SIZE + 255, "cp '%s' '%s'",
 +			      tmp_filename_symlink, cache_filename);
 +
 +	if (len > MAX_FILENAME_SIZE + 255 ||
 +	    symlink(frame->original_filename, tmp_filename_symlink) ||
 +	    system(command) != 0) {
 +		fprintf(stderr,
 +			"Could not copy the image "
 +			"%s (symlink %s) to %s",
 +			sanitized_filename(frame->original_filename),
 +			tmp_filename_symlink, cache_filename);
 +		if (cmd)
 +			gr_reporterror_cmd(cmd, "EBADF: could not copy the "
 +						"image to the cache dir");
 +		frame->status = STATUS_UPLOADING_ERROR;
 +		frame->uploading_failure = ERROR_CANNOT_COPY_FILE;
 +		// Delete the symlink.
 +		unlink(tmp_filename_symlink);
 +		return;
 +	}
 +
 +	// Delete the symlink.
 +	unlink(tmp_filename_symlink);
 +	// Set the status and update disk size variables.
 +	frame->status = STATUS_UPLOADING_SUCCESS;
 +	frame->disk_size = st.st_size;
 +	frame->image->total_disk_size += st.st_size;
 +	images_disk_size += frame->disk_size;
 +}
 +
 +/// Tries to restore the image file for `frame` if the original file is still
 +/// available.
 +static void gr_try_restore_imagefile(ImageFrame *frame) {
 +	if (frame->disk_size != 0)
 +		return;
 +	if (gr_is_original_file_still_available(frame))
 +		gr_copy_imagefile(frame, NULL);
 +}
 +
 +/// Handles a data transmission command.
 +static ImageFrame *gr_handle_transmit_command(GraphicsCommand *cmd) {
 +	// The default is direct transmission.
 +	if (!cmd->transmission_medium)
 +		cmd->transmission_medium = 'd';
 +
 +	// If neither id, nor image number is specified, and the transmission
 +	// medium is 'd' (or unspecified), and there is an active direct upload,
 +	// this is a continuation of the upload.
 +	if (current_upload_image_id != 0 && cmd->image_id == 0 &&
 +	    cmd->image_number == 0 && cmd->transmission_medium == 'd') {
 +		cmd->image_id = current_upload_image_id;
 +		GR_LOG("No images id is specified, continuing uploading %u\n",
 +		       cmd->image_id);
 +	}
 +
 +	ImageFrame *frame = NULL;
 +	if (cmd->transmission_medium == 'f' ||
 +	    cmd->transmission_medium == 't') {
 +		// File transmission.
 +		// Create a new image or a new frame of an existing image.
 +		frame = gr_new_image_or_frame_from_command(cmd);
 +		if (!frame)
 +			return NULL;
 +		last_image_id = frame->image->image_id;
 +		// Decode the filename.
 +		frame->original_filename = gr_base64dec(cmd->payload, NULL);
 +		// Copy the file to the cache directory.
 +		gr_copy_imagefile(frame, cmd);
 +		if (frame->status == STATUS_UPLOADING_SUCCESS) {
 +			// Everything seems fine, try to load and redraw
 +			// existing instances.
 +			gr_schedule_image_redraw(frame->image);
 +			frame = gr_loadimage_and_report(frame);
 +		}
 +		// Delete the original file if it's temporary.
 +		if (cmd->transmission_medium == 't')
 +			gr_delete_tmp_file(frame->original_filename);
 +		gr_check_limits();
 +	} else if (cmd->transmission_medium == 'd') {
 +		// Direct transmission (default if 't' is not specified).
 +		frame = gr_get_last_frame(gr_find_image_for_command(cmd));
 +		if (gr_transmission_continuation_is_allowed(cmd, frame)) {
 +			// This is a continuation of the previous transmission.
 +			cmd->is_direct_transmission_continuation = 1;
 +			cmd->image_id = frame->image->image_id;
 +			gr_append_data(frame, cmd->payload, cmd->more);
 +			return frame;
 +		}
 +		// Otherwise create a new image or frame structure.
 +		frame = gr_new_image_or_frame_from_command(cmd);
 +		if (!frame)
 +			return NULL;
 +		last_image_id = frame->image->image_id;
 +		frame->status = STATUS_UPLOADING;
 +		// Start appending data.
 +		gr_append_data(frame, cmd->payload, cmd->more);
 +	} else if (cmd->transmission_medium == 's') {
 +		// Shared memory transmission.
 +		// Create a new image or a new frame of an existing image.
 +		frame = gr_new_image_or_frame_from_command(cmd);
 +		if (!frame)
 +			return NULL;
 +		last_image_id = frame->image->image_id;
 +		// Check that we know the size.
 +		if (!frame->expected_size) {
 +			frame->status = STATUS_UPLOADING_ERROR;
 +			frame->uploading_failure = ERROR_UNEXPECTED_SIZE;
 +			gr_reporterror_cmd(
 +				cmd, "EINVAL: the size of the image is not "
 +				     "specified and cannot be inferred");
 +			return frame;
 +		}
 +		// Check the data size limit.
 +		if (frame->expected_size > graphics_max_single_image_file_size) {
 +			frame->uploading_failure = ERROR_OVER_SIZE_LIMIT;
 +			gr_reportuploaderror(frame);
 +			return frame;
 +		}
 +		// Decode the filename.
 +		char *original_filename = gr_base64dec(cmd->payload, NULL);
 +		GR_LOG("Loading image from shared memory %s\n",
 +		       sanitized_filename(original_filename));
 +		// Open the shared memory object.
 +		int fd = shm_open(original_filename, O_RDONLY, 0);
 +		if (fd == -1) {
 +			gr_reporterror_cmd(cmd, "EBADF: shm_open: %s",
 +					   strerror(errno));
 +			frame->status = STATUS_UPLOADING_ERROR;
 +			frame->uploading_failure = ERROR_CANNOT_OPEN_SHM;
 +			fprintf(stderr, "shm_open failed for %s\n",
 +				sanitized_filename(original_filename));
 +			shm_unlink(original_filename);
 +			free(original_filename);
 +			return frame;
 +		}
 +		shm_unlink(original_filename);
 +		free(original_filename);
 +		// The offset we pass to mmap must be a multiple of the page
 +		// size. If it's not, adjust it and the size.
 +		size_t page_size = sysconf(_SC_PAGESIZE);
 +		if (page_size == -1)
 +			page_size = 1;
 +		size_t offset = cmd->offset - (cmd->offset % page_size);
 +		size_t size = frame->expected_size + (cmd->offset - offset);
 +		// Map the shared memory object.
 +		void *data =
 +			mmap(NULL, size, PROT_READ, MAP_SHARED, fd, offset);
 +		if (data == MAP_FAILED) {
 +			gr_reporterror_cmd(cmd, "EBADF: mmap: %s",
 +					   strerror(errno));
 +			frame->status = STATUS_UPLOADING_ERROR;
 +			frame->uploading_failure = ERROR_CANNOT_OPEN_SHM;
 +			fprintf(stderr,
 +				"mmap failed for size = %ld, offset = %ld\n",
 +				size, offset);
 +			close(fd);
 +			return frame;
 +		}
 +		close(fd);
 +		// Append the data to the cache file.
 +		if (gr_append_raw_data_to_file(frame,
 +					       data + (cmd->offset - offset),
 +					       frame->expected_size)) {
 +			frame->status = STATUS_UPLOADING_SUCCESS;
 +		} else {
 +			frame->status = STATUS_UPLOADING_ERROR;
 +			frame->uploading_failure =
 +				ERROR_CANNOT_OPEN_CACHED_FILE;
 +			gr_reportuploaderror(frame);
 +		}
 +		// Close the cache file.
 +		gr_close_disk_cache_file(frame);
 +		// Unmap the data
 +		if (munmap(data, size) != 0)
 +			fprintf(stderr, "munmap failed: %s\n", strerror(errno));
 +		// Try to load and redraw existing instances.
 +		gr_schedule_image_redraw(frame->image);
 +		frame = gr_loadimage_and_report(frame);
 +		gr_check_limits();
 +	} else {
 +		gr_reporterror_cmd(
 +			cmd,
 +			"EINVAL: transmission medium '%c' is not supported",
 +			cmd->transmission_medium);
 +		return NULL;
 +	}
 +
 +	return frame;
 +}
 +
 +/// Handles the 'put' command by creating a placement.
 +static void gr_handle_put_command(GraphicsCommand *cmd) {
 +	if (cmd->image_id == 0 && cmd->image_number == 0) {
 +		gr_reporterror_cmd(cmd,
 +				   "EINVAL: neither image id nor image number "
 +				   "are specified or both are zero");
 +		return;
 +	}
 +
 +	// Find the image with the id or number.
 +	Image *img = gr_find_image_for_command(cmd);
 +	if (img) {
 +		cmd->image_id = img->image_id;
 +	} else {
 +		gr_reporterror_cmd(cmd, "ENOENT: image not found");
 +		return;
 +	}
 +
 +	// Create a placement. If a placement with the same id already exists,
 +	// it will be deleted. If the id is zero, a random id will be generated.
 +	ImagePlacement *placement = gr_new_placement(img, cmd->placement_id);
 +	placement->virtual = cmd->virtual;
 +	placement->src_pix_x = cmd->src_pix_x;
 +	placement->src_pix_y = cmd->src_pix_y;
 +	placement->src_pix_width = cmd->src_pix_width;
 +	placement->src_pix_height = cmd->src_pix_height;
 +	placement->cols = cmd->columns;
 +	placement->rows = cmd->rows;
 +	placement->do_not_move_cursor = cmd->do_not_move_cursor;
 +
 +	if (placement->virtual) {
 +		placement->scale_mode = SCALE_MODE_CONTAIN;
 +	} else if (placement->cols && placement->rows) {
 +		// For classic placements the default is to stretch the image if
 +		// both cols and rows are specified.
 +		placement->scale_mode = SCALE_MODE_FILL;
 +	} else if (placement->cols || placement->rows) {
 +		// But if only one of them is specified, the default is to
 +		// contain.
 +		placement->scale_mode = SCALE_MODE_CONTAIN;
 +	} else {
 +		// If none of them are specified, the default is to use the
 +		// original size.
 +		placement->scale_mode = SCALE_MODE_NONE;
 +	}
 +
 +	// Display the placement unless it's virtual.
 +	gr_display_nonvirtual_placement(placement);
 +
 +	// Report success.
 +	gr_reportsuccess_cmd(cmd);
 +}
 +
 +/// Information about what to delete.
 +typedef struct DeletionData {
 +	uint32_t image_id;
 +	uint32_t placement_id;
 +	/// Visible placement found during screen traversal that need to be
 +	/// deleted. Each placement must occur only once in this vector.
 +	ImagePlacementVec placements_to_delete;
 +} DeletionData;
 +
 +/// The callback called for each cell to perform deletion.
 +static int gr_deletion_callback(void *data, Glyph *gp) {
 +	DeletionData *del_data = data;
 +	// Leave unicode placeholders alone.
 +	if (!tgetisclassicplaceholder(gp))
 +		return 0;
 +	uint32_t image_id = tgetimgid(gp);
 +	uint32_t placement_id = tgetimgplacementid(gp);
 +	if (del_data->image_id && del_data->image_id != image_id)
 +		return 0;
 +	if (del_data->placement_id && del_data->placement_id != placement_id)
 +		return 0;
 +
 +	ImagePlacement *placement = NULL;
 +
 +	// Record the placement to delete. We will actually delete it later.
 +	for (int i = 0; i < kv_size(del_data->placements_to_delete); ++i) {
 +		ImagePlacement *cand = kv_A(del_data->placements_to_delete, i);
 +		if (cand->image->image_id == image_id &&
 +		    cand->placement_id == placement_id) {
 +			placement = cand;
 +			break;
 +		}
 +	}
 +	if (!placement) {
 +		placement = gr_find_image_and_placement(image_id, placement_id);
 +		if (placement) {
 +			kv_push(ImagePlacement *,
 +				del_data->placements_to_delete, placement);
 +		}
 +	}
 +
 +	// Restore the text underneath the placement if possible.
 +	if (placement && placement->text_underneath) {
 +		int row = tgetimgrow(gp) - 1;
 +		int col = tgetimgcol(gp) - 1;
 +		if (col >= 0 && row >= 0 && row < placement->rows &&
 +		    col < placement->cols) {
 +			*gp = placement->text_underneath[row * placement->cols +
 +							 col];
 +			return 1;
 +		}
 +	}
 +
 +	// Otherwise just erase the cell.
 +	gp->mode = 0;
 +	gp->u = ' ';
 +	return 1;
 +}
 +
 +/// Handles the delete command.
 +static void gr_handle_delete_command(GraphicsCommand *cmd) {
 +	DeletionData del_data = {0};
 +	char delete_image_if_no_ref = isupper(cmd->delete_specifier) != 0;
 +	char d = tolower(cmd->delete_specifier);
 +
 +	if (d == 'n') {
 +		d = 'i';
 +		Image *img = gr_find_image_by_number(cmd->image_number);
 +		if (!img)
 +			return;
 +		del_data.image_id = img->image_id;
 +	}
 +
 +	kv_init(del_data.placements_to_delete);
 +
 +	if (!d || d == 'a') {
 +		// Delete all visible placements.
 +		gr_for_each_image_cell(gr_deletion_callback, &del_data);
 +	} else if (d == 'i') {
 +		// Delete the specified image by image id and maybe placement
 +		// id.
 +		if (!del_data.image_id)
 +			del_data.image_id = cmd->image_id;
 +		if (!del_data.image_id) {
 +			fprintf(stderr,
 +				"ERROR: image id is not specified in the "
 +				"delete command\n");
 +			kv_destroy(del_data.placements_to_delete);
 +			return;
 +		}
 +		del_data.placement_id = cmd->placement_id;
 +		gr_for_each_image_cell(gr_deletion_callback, &del_data);
 +	} else {
 +		fprintf(stderr,
 +			"WARNING: unsupported value of the d key: '%c'. The "
 +			"command is ignored.\n",
 +			cmd->delete_specifier);
 +	}
 +
 +	// Delete the placements we have collected and maybe images too.
 +	for (int i = 0; i < kv_size(del_data.placements_to_delete); ++i) {
 +		ImagePlacement *placement =
 +			kv_A(del_data.placements_to_delete, i);
 +		// Delete the text underneath the placement and set it to NULL
 +		// to avoid erasing it from the screen again.
 +		free(placement->text_underneath);
 +		placement->text_underneath = NULL;
 +		Image *img = placement->image;
 +		gr_delete_placement(placement);
 +		// Delete the image if image deletion is requested (uppercase
 +		// delete specifier) and there are no more placements.
 +		if (delete_image_if_no_ref && kh_size(img->placements) == 0)
 +			gr_delete_image(img);
 +	}
 +
 +	// NOTE: It's not very clear whether we should delete the image
 +	// even if there are no _visible_ placements to delete. We do
 +	// this because otherwise there is no way to delete an image
 +	// with virtual placements in one command.
 +	if (d == 'i' && !del_data.placement_id && delete_image_if_no_ref)
 +		gr_delete_image(gr_find_image(cmd->image_id));
 +
 +	kv_destroy(del_data.placements_to_delete);
 +}
 +
 +/// Clears the cells occupied by the placement. This is normally done when
 +/// implicitly deleting a classic placement.
 +static void gr_erase_placement(ImagePlacement *placement) {
 +	DeletionData del_data = {0};
 +	del_data.image_id = placement->image->image_id;
 +	del_data.placement_id = placement->placement_id;
 +	kv_init(del_data.placements_to_delete);
 +	gr_for_each_image_cell(gr_deletion_callback, &del_data);
 +	// Delete the text underneath the placement and set it to NULL
 +	// to avoid erasing it from the screen again.
 +	free(placement->text_underneath);
 +	placement->text_underneath = NULL;
 +	kv_destroy(del_data.placements_to_delete);
 +}
 +
 +static void gr_handle_animation_control_command(GraphicsCommand *cmd) {
 +	if (cmd->image_id == 0 && cmd->image_number == 0) {
 +		gr_reporterror_cmd(cmd,
 +				   "EINVAL: neither image id nor image number "
 +				   "are specified or both are zero");
 +		return;
 +	}
 +
 +	// Find the image with the id or number.
 +	Image *img = gr_find_image_for_command(cmd);
 +	if (img) {
 +		cmd->image_id = img->image_id;
 +	} else {
 +		gr_reporterror_cmd(cmd, "ENOENT: image not found");
 +		return;
 +	}
 +
 +	// Find the frame to edit, if requested.
 +	ImageFrame *frame = NULL;
 +	if (cmd->edit_frame)
 +		frame = gr_get_frame(img, cmd->edit_frame);
 +	if (cmd->edit_frame || cmd->gap) {
 +		if (!frame) {
 +			gr_reporterror_cmd(cmd, "ENOENT: frame %d not found",
 +					   cmd->edit_frame);
 +			return;
 +		}
 +		if (cmd->gap) {
 +			img->total_duration -= frame->gap;
 +			frame->gap = cmd->gap;
 +			img->total_duration += frame->gap;
 +		}
 +	}
 +
 +	// Set animation-related parameters of the image.
 +	if (cmd->current_frame)
 +		img->current_frame = cmd->current_frame;
 +	if (cmd->animation_state) {
 +		if (cmd->animation_state == 1) {
 +			img->animation_state = ANIMATION_STATE_STOPPED;
 +		} else if (cmd->animation_state == 2) {
 +			img->animation_state = ANIMATION_STATE_LOADING;
 +		} else if (cmd->animation_state == 3) {
 +			img->animation_state = ANIMATION_STATE_LOOPING;
 +		} else {
 +			gr_reporterror_cmd(
 +				cmd, "EINVAL: invalid animation state: %d",
 +				cmd->animation_state);
 +		}
 +	}
 +	// TODO: Set the number of loops to cmd->loops
 +
 +	// Make sure we redraw all instances of the image.
 +	gr_schedule_image_redraw(img);
 +}
 +
 +/// Handles a command.
 +static void gr_handle_command(GraphicsCommand *cmd) {
 +	if (!cmd->image_id && !cmd->image_number) {
 +		// If there is no image id or image number, nobody expects a
 +		// response, so set quiet to 2.
 +		cmd->quiet = 2;
 +	}
 +
 +	int was_transmission = 0;
 +	ImageFrame *frame = NULL;
 +
 +	switch (cmd->action) {
 +	case 0:
 +		// If no action is specified, it is data transmission.
 +	case 't':
 +	case 'q':
 +	case 'f':
 +		was_transmission = 1;
 +		// Transmit data. 'q' means query, which is basically the same
 +		// as transmit, but the image is discarded, and the id is fake.
 +		// 'f' appends a frame to an existing image.
 +		gr_handle_transmit_command(cmd);
 +		break;
 +	case 'p':
 +		// Display (put) the image.
 +		gr_handle_put_command(cmd);
 +		break;
 +	case 'T':
 +		was_transmission = 1;
 +		// Transmit and display.
 +		frame = gr_handle_transmit_command(cmd);
 +		if (frame && !cmd->is_direct_transmission_continuation) {
 +			gr_handle_put_command(cmd);
 +			if (cmd->placement_id)
 +				frame->image->initial_placement_id =
 +					cmd->placement_id;
 +		}
 +		break;
 +	case 'd':
 +		gr_handle_delete_command(cmd);
 +		break;
 +	case 'a':
 +		gr_handle_animation_control_command(cmd);
 +		break;
 +	default:
 +		gr_reporterror_cmd(cmd, "EINVAL: unsupported action: %c",
 +				   cmd->action);
 +		break;
 +	}
 +
 +	if (!was_transmission ||
 +	    (cmd->transmission_medium && cmd->transmission_medium != 'd')) {
 +		// If it wasn't a transmission command, or if the transmission
 +		// wasn't direct, clear the current upload frame and close the
 +		// file. (If it was a direct transmission, the current upload
 +		// was handled inside `gr_append_data`.)
 +		gr_set_current_upload_frame(NULL);
 +	}
 +}
 +
 +/// A partially parsed key-value pair.
 +typedef struct KeyAndValue {
 +	char *key_start;
 +	char *val_start;
 +	unsigned key_len, val_len;
 +} KeyAndValue;
 +
 +/// Parses the value of a key and assigns it to the appropriate field of `cmd`.
 +static void gr_set_keyvalue(GraphicsCommand *cmd, KeyAndValue *kv) {
 +	char *key_start = kv->key_start;
 +	char *key_end = key_start + kv->key_len;
 +	char *value_start = kv->val_start;
 +	char *value_end = value_start + kv->val_len;
 +	// Currently all keys are one-character.
 +	if (key_end - key_start != 1) {
 +		gr_reporterror_cmd(cmd, "EINVAL: unknown key of length %ld: %s",
 +				   key_end - key_start, key_start);
 +		return;
 +	}
 +	long num = 0;
 +	if (*key_start == 'a' || *key_start == 't' || *key_start == 'd' ||
 +	    *key_start == 'o') {
 +		// Some keys have one-character values.
 +		if (value_end - value_start != 1) {
 +			gr_reporterror_cmd(
 +				cmd,
 +				"EINVAL: value of 'a', 't' or 'd' must be a "
 +				"single char: %s",
 +				key_start);
 +			return;
 +		}
 +	} else {
 +		// All the other keys have integer values.
 +		char *num_end = NULL;
 +		num = strtol(value_start, &num_end, 10);
 +		if (num_end != value_end) {
 +			gr_reporterror_cmd(
 +				cmd, "EINVAL: could not parse number value: %s",
 +				key_start);
 +			return;
 +		}
 +	}
 +	switch (*key_start) {
 +	case 'a':
 +		cmd->action = *value_start;
 +		break;
 +	case 't':
 +		cmd->transmission_medium = *value_start;
 +		break;
 +	case 'd':
 +		cmd->delete_specifier = *value_start;
 +		break;
 +	case 'q':
 +		cmd->quiet = num;
 +		break;
 +	case 'f':
 +		cmd->format = num;
 +		if (num != 0 && num != 24 && num != 32 && num != 100) {
 +			gr_reporterror_cmd(
 +				cmd,
 +				"EINVAL: unsupported format specification: %s",
 +				key_start);
 +		}
 +		break;
 +	case 'o':
 +		cmd->compression = *value_start;
 +		if (cmd->compression != 'z') {
 +			gr_reporterror_cmd(cmd,
 +					   "EINVAL: unsupported compression "
 +					   "specification: %s",
 +					   key_start);
 +		}
 +		break;
 +	case 's':
 +		if (cmd->action == 'a')
 +			cmd->animation_state = num;
 +		else
 +			cmd->frame_pix_width = num;
 +		break;
 +	case 'v':
 +		if (cmd->action == 'a')
 +			cmd->loops = num;
 +		else
 +			cmd->frame_pix_height = num;
 +		break;
 +	case 'i':
 +		cmd->image_id = num;
 +		break;
 +	case 'I':
 +		cmd->image_number = num;
 +		break;
 +	case 'p':
 +		cmd->placement_id = num;
 +		break;
 +	case 'x':
 +		cmd->src_pix_x = num;
 +		cmd->frame_dst_pix_x = num;
 +		break;
 +	case 'y':
 +		if (cmd->action == 'f')
 +			cmd->frame_dst_pix_y = num;
 +		else
 +			cmd->src_pix_y = num;
 +		break;
 +	case 'w':
 +		cmd->src_pix_width = num;
 +		break;
 +	case 'h':
 +		cmd->src_pix_height = num;
 +		break;
 +	case 'c':
 +		if (cmd->action == 'f')
 +			cmd->background_frame = num;
 +		else if (cmd->action == 'a')
 +			cmd->current_frame = num;
 +		else
 +			cmd->columns = num;
 +		break;
 +	case 'r':
 +		if (cmd->action == 'f' || cmd->action == 'a')
 +			cmd->edit_frame = num;
 +		else
 +			cmd->rows = num;
 +		break;
 +	case 'm':
 +		cmd->more = num;
 +		break;
 +	case 'S':
 +		cmd->size = num;
 +		break;
 +	case 'O':
 +		cmd->offset = num;
 +		break;
 +	case 'U':
 +		cmd->virtual = num;
 +		break;
 +	case 'X':
 +		if (cmd->action == 'f')
 +			cmd->replace_instead_of_blending = num;
 +		else
 +			break; /*ignore*/
 +		break;
 +	case 'Y':
 +		if (cmd->action == 'f')
 +			cmd->background_color = num;
 +		else
 +			break; /*ignore*/
 +		break;
 +	case 'z':
 +		if (cmd->action == 'f' || cmd->action == 'a')
 +			cmd->gap = num;
 +		else
 +			break; /*ignore*/
 +		break;
 +	case 'C':
 +		cmd->do_not_move_cursor = num;
 +		break;
 +	default:
 +		gr_reporterror_cmd(cmd, "EINVAL: unsupported key: %s",
 +				   key_start);
 +		return;
 +	}
 +}
 +
 +/// Parse and execute a graphics command. `buf` must start with 'G' and contain
 +/// at least `len + 1` characters. Returns 1 on success.
 +int gr_parse_command(char *buf, size_t len) {
 +	if (buf[0] != 'G')
 +		return 0;
 +
 +	Milliseconds command_start_time = gr_now_ms();
 +	debug_loaded_files_counter = 0;
 +	debug_loaded_pixmaps_counter = 0;
 +	global_command_counter++;
 +	GR_LOG("### Command %lu: %.80s\n", global_command_counter, buf);
 +
 +	memset(&graphics_command_result, 0, sizeof(GraphicsCommandResult));
 +
 +	// Eat the 'G'.
 +	++buf;
 +	--len;
 +
 +	GraphicsCommand cmd = {.command = buf};
 +	// The state of parsing. 'k' to parse key, 'v' to parse value, 'p' to
 +	// parse the payload.
 +	char state = 'k';
 +	// An array of partially parsed key-value pairs.
 +	KeyAndValue key_vals[32];
 +	unsigned key_vals_count = 0;
 +	char *key_start = buf;
 +	char *key_end = NULL;
 +	char *val_start = NULL;
 +	char *val_end = NULL;
 +	char *c = buf;
 +	while (c - buf < len + 1) {
 +		if (state == 'k') {
 +			switch (*c) {
 +			case ',':
 +			case ';':
 +			case '\0':
 +				state = *c == ',' ? 'k' : 'p';
 +				key_end = c;
 +				gr_reporterror_cmd(
 +					&cmd, "EINVAL: key without value: %s ",
 +					key_start);
 +				break;
 +			case '=':
 +				key_end = c;
 +				state = 'v';
 +				val_start = c + 1;
 +				break;
 +			default:
 +				break;
 +			}
 +		} else if (state == 'v') {
 +			switch (*c) {
 +			case ',':
 +			case ';':
 +			case '\0':
 +				state = *c == ',' ? 'k' : 'p';
 +				val_end = c;
 +				if (key_vals_count >=
 +				    sizeof(key_vals) / sizeof(*key_vals)) {
 +					gr_reporterror_cmd(&cmd,
 +							   "EINVAL: too many "
 +							   "key-value pairs");
 +					break;
 +				}
 +				key_vals[key_vals_count].key_start = key_start;
 +				key_vals[key_vals_count].val_start = val_start;
 +				key_vals[key_vals_count].key_len =
 +					key_end - key_start;
 +				key_vals[key_vals_count].val_len =
 +					val_end - val_start;
 +				++key_vals_count;
 +				key_start = c + 1;
 +				break;
 +			default:
 +				break;
 +			}
 +		} else if (state == 'p') {
 +			cmd.payload = c;
 +			// break out of the loop, we don't check the payload
 +			break;
 +		}
 +		++c;
 +	}
 +
 +	// Set the action key ('a=') first because we need it to disambiguate
 +	// some keys. Also set 'i=' and 'I=' for better error reporting.
 +	for (unsigned i = 0; i < key_vals_count; ++i) {
 +		if (key_vals[i].key_len == 1) {
 +			char *start = key_vals[i].key_start;
 +			if (*start == 'a' || *start == 'i' || *start == 'I') {
 +				gr_set_keyvalue(&cmd, &key_vals[i]);
 +				break;
 +			}
 +		}
 +	}
 +	// Set the rest of the keys.
 +	for (unsigned i = 0; i < key_vals_count; ++i)
 +		gr_set_keyvalue(&cmd, &key_vals[i]);
 +
 +	if (!cmd.payload)
 +		cmd.payload = buf + len;
 +
 +	if (cmd.payload && cmd.payload[0])
 +		GR_LOG("    payload size: %ld\n", strlen(cmd.payload));
 +
 +	if (!graphics_command_result.error)
 +		gr_handle_command(&cmd);
 +
 +	if (graphics_debug_mode) {
 +		fprintf(stderr, "Response: ");
 +		for (const char *resp = graphics_command_result.response;
 +		     *resp != '\0'; ++resp) {
 +			if (isprint(*resp))
 +				fprintf(stderr, "%c", *resp);
 +			else
 +				fprintf(stderr, "(0x%x)", *resp);
 +		}
 +		fprintf(stderr, "\n");
 +	}
 +
 +	// Make sure that we suppress response if needed. Usually cmd.quiet is
 +	// taken into account when creating the response, but it's not very
 +	// reliable in the current implementation.
 +	if (cmd.quiet) {
 +		if (!graphics_command_result.error || cmd.quiet >= 2)
 +			graphics_command_result.response[0] = '\0';
 +	}
 +
 +	Milliseconds command_end_time = gr_now_ms();
 +	GR_LOG("Command %lu took %ld ms  (loaded %d files, %d pixmaps)\n\n",
 +	       global_command_counter, command_end_time - command_start_time,
 +	       debug_loaded_files_counter, debug_loaded_pixmaps_counter);
 +
 +	return 1;
 +}
 +
 +////////////////////////////////////////////////////////////////////////////////
 +// base64 decoding part is basically copied from st.c
 +////////////////////////////////////////////////////////////////////////////////
 +
 +static const char gr_base64_digits[] = {
 +	0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
 +	0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
 +	0,  0,  0,  0,  0,  0,  0,  0,  0,  62, 0,  0,  0,  63, 52, 53, 54,
 +	55, 56, 57, 58, 59, 60, 61, 0,  0,  0,  -1, 0,  0,  0,  0,  1,  2,
 +	3,  4,  5,  6,  7,  8,  9,  10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
 +	20, 21, 22, 23, 24, 25, 0,  0,  0,  0,  0,  0,  26, 27, 28, 29, 30,
 +	31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
 +	48, 49, 50, 51, 0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
 +	0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
 +	0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
 +	0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
 +	0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
 +	0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
 +	0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
 +	0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0};
 +
 +static char gr_base64_getc(const char **src) {
 +	while (**src && !isprint(**src))
 +		(*src)++;
 +	return **src ? *((*src)++) : '='; /* emulate padding if string ends */
 +}
 +
 +char *gr_base64dec(const char *src, size_t *size) {
 +	size_t in_len = strlen(src);
 +	char *result, *dst;
 +
 +	result = dst = malloc((in_len + 3) / 4 * 3 + 1);
 +	while (*src) {
 +		int a = gr_base64_digits[(unsigned char)gr_base64_getc(&src)];
 +		int b = gr_base64_digits[(unsigned char)gr_base64_getc(&src)];
 +		int c = gr_base64_digits[(unsigned char)gr_base64_getc(&src)];
 +		int d = gr_base64_digits[(unsigned char)gr_base64_getc(&src)];
 +
 +		if (a == -1 || b == -1)
 +			break;
 +
 +		*dst++ = (a << 2) | ((b & 0x30) >> 4);
 +		if (c == -1)
 +			break;
 +		*dst++ = ((b & 0x0f) << 4) | ((c & 0x3c) >> 2);
 +		if (d == -1)
 +			break;
 +		*dst++ = ((c & 0x03) << 6) | d;
 +	}
 +	*dst = '\0';
 +	if (size) {
 +		*size = dst - result;
 +	}
 +	return result;
 +}
 diff --git a/graphics.h b/graphics.h
 new file mode 100644
 index 0000000..f9a649a
 --- /dev/null
 +++ b/graphics.h
 @@ -0,0 +1,112 @@
 +
 +#include <stdint.h>
 +#include <sys/types.h>
 +#include <X11/Xlib.h>
 +
 +/// Initialize the graphics module.
 +void gr_init(Display *disp, Visual *vis, Colormap cm);
 +/// Deinitialize the graphics module.
 +void gr_deinit();
 +
 +/// Add an image rectangle to a list if rectangles to draw. This function may
 +/// actually draw some rectangles, or it may wait till more rectangles are
 +/// appended. Must be called between `gr_start_drawing` and `gr_finish_drawing`.
 +/// - `img_start_col..img_end_col` and `img_start_row..img_end_row` define the
 +///   part of the image to draw (row/col indices are zero-based, ends are
 +///   excluded).
 +/// - `x_col` and `y_row` are the coordinates of the top-left corner of the
 +///   image in the terminal grid.
 +/// - `x_pix` and `y_pix` are the same but in pixels.
 +/// - `reverse` indicates whether colors should be inverted.
 +void gr_append_imagerect(Drawable buf, uint32_t image_id, uint32_t placement_id,
 +			 int img_start_col, int img_end_col, int img_start_row,
 +			 int img_end_row, int x_col, int y_row, int x_pix,
 +			 int y_pix, int cw, int ch, int reverse);
 +/// Prepare for image drawing. `cw` and `ch` are dimensions of the cell.
 +void gr_start_drawing(Drawable buf, int cw, int ch);
 +/// Finish image drawing. This functions will draw all the rectangles left to
 +/// draw.
 +void gr_finish_drawing(Drawable buf);
 +/// Mark rows containing animations as dirty if it's time to redraw them. Must
 +/// be called right after `gr_start_drawing`.
 +void gr_mark_dirty_animations(int *dirty, int rows);
 +
 +/// Parse and execute a graphics command. `buf` must start with 'G' and contain
 +/// at least `len + 1` characters (including '\0'). Returns 1 on success.
 +/// Additional informations is returned through `graphics_command_result`.
 +int gr_parse_command(char *buf, size_t len);
 +
 +/// Executes `command` with the name of the file corresponding to `image_id` as
 +/// the argument. Executes xmessage with an error message on failure.
 +void gr_preview_image(uint32_t image_id, const char *command);
 +
 +/// Executes `<st> -e less <file>` where <file> is the name of a temporary file
 +/// containing the information about an image and placement, and <st> is
 +/// specified with `st_executable`.
 +void gr_show_image_info(uint32_t image_id, uint32_t placement_id,
 +			uint32_t imgcol, uint32_t imgrow,
 +			char is_classic_placeholder, int32_t diacritic_count,
 +			char *st_executable);
 +
 +/// Dumps the internal state (images and placements) to stderr.
 +void gr_dump_state();
 +
 +/// Unloads images to reduce RAM usage.
 +void gr_unload_images_to_reduce_ram();
 +
 +/// Executes `callback` for each image cell. The callback should return 1 if it
 +/// changed the glyph. This function is implemented in `st.c`.
 +void gr_for_each_image_cell(int (*callback)(void *data, Glyph *gp),
 +			    void *data);
 +
 +/// Marks all the rows containing the image with `image_id` as dirty.
 +void gr_schedule_image_redraw_by_id(uint32_t image_id);
 +
 +/// Returns a pointer to the glyph under the classic placement with `image_id`
 +/// and `placement_id` at `col` and `row` (1-based). May return NULL if the
 +/// underneath text is unknown.
 +Glyph *gr_get_glyph_underneath_image(uint32_t image_id, uint32_t placement_id,
 +				     int col, int row);
 +
 +typedef enum {
 +	GRAPHICS_DEBUG_NONE = 0,
 +	GRAPHICS_DEBUG_LOG = 1,
 +	GRAPHICS_DEBUG_LOG_AND_BOXES = 2,
 +} GraphicsDebugMode;
 +
 +/// Print additional information, draw bounding bounding boxes, etc.
 +extern GraphicsDebugMode graphics_debug_mode;
 +
 +/// Whether to display images or just draw bounding boxes.
 +extern char graphics_display_images;
 +
 +/// The time in milliseconds until the next redraw to update animations.
 +/// INT_MAX means no redraw is needed. Populated by `gr_finish_drawing`.
 +extern int graphics_next_redraw_delay;
 +
 +#define MAX_GRAPHICS_RESPONSE_LEN 256
 +
 +/// A structure representing the result of a graphics command.
 +typedef struct {
 +	/// Indicates if the terminal needs to be redrawn.
 +	char redraw;
 +	/// The response of the command that should be sent back to the client
 +	/// (may be empty if the quiet flag is set).
 +	char response[MAX_GRAPHICS_RESPONSE_LEN];
 +	/// Whether there was an error executing this command (not very useful,
 +	/// the response must be sent back anyway).
 +	char error;
 +	/// Whether the terminal has to create a placeholder for a non-virtual
 +	/// placement.
 +	char create_placeholder;
 +	/// The placeholder that needs to be created.
 +	struct {
 +		uint32_t rows, columns;
 +		uint32_t image_id, placement_id;
 +		char do_not_move_cursor;
 +		Glyph *text_underneath;
 +	} placeholder;
 +} GraphicsCommandResult;
 +
 +/// The result of a graphics command.
 +extern GraphicsCommandResult graphics_command_result;
 diff --git a/icat-mini.sh b/icat-mini.sh
 new file mode 100755
 index 0000000..8f240e9
 --- /dev/null
 +++ b/icat-mini.sh
 @@ -0,0 +1,875 @@
 +#!/bin/sh
 +
 +# vim: shiftwidth=4
 +
 +script_name="$(basename "$0")"
 +
 +short_help="Usage: $script_name [OPTIONS] <image_file>
 +
 +This is a script to display images in the terminal using the kitty graphics
 +protocol with Unicode placeholders. It is very basic, please use something else
 +if you have alternatives.
 +
 +Options:
 +  -h                  Show this help.
 +  -s SCALE            The scale of the image, may be floating point.
 +  -c N, --cols N      The number of columns.
 +  -r N, --rows N      The number of rows.
 +  --max-cols N        The maximum number of columns.
 +  --max-rows N        The maximum number of rows.
 +  --cell-size WxH     The cell size in pixels.
 +  -m METHOD           The uploading method, may be 'file', 'direct' or 'auto'.
 +  --speed SPEED       The multiplier for the animation speed (float).
 +"
 +
 +# Exit the script on keyboard interrupt
 +trap "echo 'icat-mini was interrupted' >&2; exit 1" INT
 +
 +cols=""
 +rows=""
 +file=""
 +command_tty=""
 +response_tty=""
 +uploading_method="auto"
 +cell_size=""
 +scale=1
 +max_cols=""
 +max_rows=""
 +speed=""
 +
 +# Parse the command line.
 +while [ $# -gt 0 ]; do
 +    case "$1" in
 +        -c|--columns|--cols)
 +            cols="$2"
 +            shift 2
 +            ;;
 +        -r|--rows|-l|--lines)
 +            rows="$2"
 +            shift 2
 +            ;;
 +        -s|--scale)
 +            scale="$2"
 +            shift 2
 +            ;;
 +        -h|--help)
 +            echo "$short_help"
 +            exit 0
 +            ;;
 +        -m|--upload-method|--uploading-method)
 +            uploading_method="$2"
 +            shift 2
 +            ;;
 +        --cell-size)
 +            cell_size="$2"
 +            shift 2
 +            ;;
 +        --max-cols)
 +            max_cols="$2"
 +            shift 2
 +            ;;
 +        --max-rows)
 +            max_rows="$2"
 +            shift 2
 +            ;;
 +        --speed)
 +            speed="$2"
 +            shift 2
 +            ;;
 +        --)
 +            file="$2"
 +            shift 2
 +            ;;
 +        -*)
 +            echo "Unknown option: $1" >&2
 +            exit 1
 +            ;;
 +        *)
 +            if [ -n "$file" ]; then
 +                echo "Multiple image files are not supported: $file and $1" >&2
 +                exit 1
 +            fi
 +            file="$1"
 +            shift
 +            ;;
 +    esac
 +done
 +
 +file="$(realpath "$file")"
 +
 +#####################################################################
 +# Detect imagemagick
 +#####################################################################
 +
 +# If there is the 'magick' command, use it instead of separate 'convert' and
 +# 'identify' commands.
 +if command -v magick > /dev/null; then
 +    identify="magick identify"
 +    convert="magick"
 +else
 +    identify="identify"
 +    convert="convert"
 +fi
 +
 +#####################################################################
 +# Detect tmux
 +#####################################################################
 +
 +# Check if we are inside tmux.
 +inside_tmux=""
 +if [ -n "$TMUX" ]; then
 +    inside_tmux=1
 +fi
 +
 +if [ -z "$command_tty" ] && [ -n "$inside_tmux" ]; then
 +    # Get the pty of the current tmux pane.
 +    command_tty="$(tmux display-message -t "$TMUX_PANE" -p "#{pane_tty}")"
 +    if [ ! -e "$command_tty" ]; then
 +        command_tty=""
 +    fi
 +fi
 +
 +#####################################################################
 +# Adjust the terminal state
 +#####################################################################
 +
 +if [ -z "$command_tty" ]; then
 +    command_tty="/dev/tty"
 +fi
 +if [ -z "$response_tty" ]; then
 +    response_tty="/dev/tty"
 +fi
 +
 +stty_orig="$(stty -g < "$response_tty")"
 +stty -echo < "$response_tty"
 +# Disable ctrl-z. Pressing ctrl-z during image uploading may cause some
 +# horrible issues otherwise.
 +stty susp undef < "$response_tty"
 +stty -icanon < "$response_tty"
 +
 +restore_echo() {
 +    [ -n "$stty_orig" ] || return
 +    stty $stty_orig < "$response_tty"
 +}
 +
 +trap restore_echo EXIT TERM
 +
 +#####################################################################
 +# Compute the number of rows and columns
 +#####################################################################
 +
 +is_pos_int() {
 +    if [ -z "$1" ]; then
 +        return 1 # false
 +    fi
 +    if [ -z "$(printf '%s' "$1" | tr -d '[:digit:]')" ]; then
 +        if [ "$1" -gt 0 ]; then
 +            return 0 # true
 +        fi
 +    fi
 +    return 1 # false
 +}
 +
 +if [ -n "$cols" ] || [ -n "$rows" ]; then
 +    if [ -n "$max_cols" ] || [ -n "$max_rows" ]; then
 +        echo "You can't specify both max-cols/rows and cols/rows" >&2
 +        exit 1
 +    fi
 +fi
 +
 +# Get the max number of cols and rows.
 +[ -n "$max_cols" ] || max_cols="$(tput cols)"
 +[ -n "$max_rows" ] || max_rows="$(tput lines)"
 +if [ "$max_rows" -gt 255 ]; then
 +    max_rows=255
 +fi
 +
 +python_ioctl_command="import array, fcntl, termios
 +buf = array.array('H', [0, 0, 0, 0])
 +fcntl.ioctl(0, termios.TIOCGWINSZ, buf)
 +print(int(buf[2]/buf[1]), int(buf[3]/buf[0]))"
 +
 +# Get the cell size in pixels if either cols or rows are not specified.
 +if [ -z "$cols" ] || [ -z "$rows" ]; then
 +    cell_width=""
 +    cell_height=""
 +    # If the cell size is specified, use it.
 +    if [ -n "$cell_size" ]; then
 +        cell_width="${cell_size%x*}"
 +        cell_height="${cell_size#*x}"
 +        if ! is_pos_int "$cell_height" || ! is_pos_int "$cell_width"; then
 +            echo "Invalid cell size: $cell_size" >&2
 +            exit 1
 +        fi
 +    fi
 +    # Otherwise try to use TIOCGWINSZ ioctl via python.
 +    if [ -z "$cell_width" ] || [ -z "$cell_height" ]; then
 +        cell_size_ioctl="$(python3 -c "$python_ioctl_command" < "$command_tty" 2> /dev/null)"
 +        cell_width="${cell_size_ioctl% *}"
 +        cell_height="${cell_size_ioctl#* }"
 +        if ! is_pos_int "$cell_height" || ! is_pos_int "$cell_width"; then
 +            cell_width=""
 +            cell_height=""
 +        fi
 +    fi
 +    # If it didn't work, try to use csi XTWINOPS.
 +    if [ -z "$cell_width" ] || [ -z "$cell_height" ]; then
 +        if [ -n "$inside_tmux" ]; then
 +            printf '\ePtmux;\e\e[16t\e\\' >> "$command_tty"
 +        else
 +            printf '\e[16t' >> "$command_tty"
 +        fi
 +        # The expected response will look like ^[[6;<height>;<width>t
 +        term_response=""
 +        while true; do
 +            char=$(dd bs=1 count=1 <"$response_tty" 2>/dev/null)
 +            if [ "$char" = "t" ]; then
 +                break
 +            fi
 +            term_response="$term_response$char"
 +        done
 +        cell_height="$(printf '%s' "$term_response" | cut -d ';' -f 2)"
 +        cell_width="$(printf '%s' "$term_response" | cut -d ';' -f 3)"
 +        if ! is_pos_int "$cell_height" || ! is_pos_int "$cell_width"; then
 +            cell_width=8
 +            cell_height=16
 +        fi
 +    fi
 +fi
 +
 +# Compute a formula with bc and round to the nearest integer.
 +bc_round() {
 +    LC_NUMERIC=C printf '%.0f' "$(printf '%s\n' "scale=2;($1) + 0.5" | bc)"
 +}
 +
 +# Compute the number of rows and columns of the image.
 +if [ -z "$cols" ] || [ -z "$rows" ]; then
 +    # Get the size of the image and its resolution. If it's an animation, use
 +    # the first frame.
 +    format_output="$($identify -format '%w %h\n' "$file" | head -1)"
 +    img_width="$(printf '%s' "$format_output" | cut -d ' ' -f 1)"
 +    img_height="$(printf '%s' "$format_output" | cut -d ' ' -f 2)"
 +    if ! is_pos_int "$img_width" || ! is_pos_int "$img_height"; then
 +        echo "Couldn't get image size from identify: $format_output" >&2
 +        echo >&2
 +        exit 1
 +    fi
 +    opt_cols_expr="(${scale}*${img_width}/${cell_width})"
 +    opt_rows_expr="(${scale}*${img_height}/${cell_height})"
 +    if [ -z "$cols" ] && [ -z "$rows" ]; then
 +        # If columns and rows are not specified, compute the optimal values
 +        # using the information about rows and columns per inch.
 +        cols="$(bc_round "$opt_cols_expr")"
 +        rows="$(bc_round "$opt_rows_expr")"
 +        # Make sure that automatically computed rows and columns are within some
 +        # sane limits
 +        if [ "$cols" -gt "$max_cols" ]; then
 +            rows="$(bc_round "$rows * $max_cols / $cols")"
 +            cols="$max_cols"
 +        fi
 +        if [ "$rows" -gt "$max_rows" ]; then
 +            cols="$(bc_round "$cols * $max_rows / $rows")"
 +            rows="$max_rows"
 +        fi
 +    elif [ -z "$cols" ]; then
 +        # If only one dimension is specified, compute the other one to match the
 +        # aspect ratio as close as possible.
 +        cols="$(bc_round "${opt_cols_expr}*${rows}/${opt_rows_expr}")"
 +    elif [ -z "$rows" ]; then
 +        rows="$(bc_round "${opt_rows_expr}*${cols}/${opt_cols_expr}")"
 +    fi
 +
 +    if [ "$cols" -lt 1 ]; then
 +        cols=1
 +    fi
 +    if [ "$rows" -lt 1 ]; then
 +        rows=1
 +    fi
 +fi
 +
 +#####################################################################
 +# Generate an image id
 +#####################################################################
 +
 +image_id=""
 +while [ -z "$image_id" ]; do
 +    image_id="$(shuf -i 16777217-4294967295 -n 1)"
 +    # Check that the id requires 24-bit fg colors.
 +    if [ "$(expr \( "$image_id" / 256 \) % 65536)" -eq 0 ]; then
 +        image_id=""
 +    fi
 +done
 +
 +#####################################################################
 +# Uploading the image
 +#####################################################################
 +
 +# Choose the uploading method
 +if [ "$uploading_method" = "auto" ]; then
 +    if [ -n "$SSH_CLIENT" ] || [ -n "$SSH_TTY" ] || [ -n "$SSH_CONNECTION" ]; then
 +        uploading_method="direct"
 +    else
 +        uploading_method="file"
 +    fi
 +fi
 +
 +# Functions to emit the start and the end of a graphics command.
 +if [ -n "$inside_tmux" ]; then
 +    # If we are in tmux we have to wrap the command in Ptmux.
 +    graphics_command_start='\ePtmux;\e\e_G'
 +    graphics_command_end='\e\e\\\e\\'
 +else
 +    graphics_command_start='\e_G'
 +    graphics_command_end='\e\\'
 +fi
 +
 +# Send a graphics command with the correct start and end
 +gr_command() {
 +    printf "${graphics_command_start}%s${graphics_command_end}" "$1" >> "$command_tty"
 +}
 +
 +# Compute the size of a data chunk for direct transmission.
 +if [ "$uploading_method" = "direct" ]; then
 +    # Get the value of PIPE_BUF.
 +    pipe_buf="$(getconf PIPE_BUF "$command_tty" 2> /dev/null)"
 +    if is_pos_int "$pipe_buf"; then
 +        # Make sure it's between 512 and 4096.
 +        if [ "$(expr "$pipe_buf" \< 512)" -eq 1 ]; then
 +            pipe_buf=512
 +        elif [ "$(expr "$pipe_buf" \> 4096)" -eq 1 ]; then
 +            pipe_buf=4096
 +        fi
 +    else
 +        pipe_buf=512
 +    fi
 +
 +    # The size of each graphics command shouldn't be more than PIPE_BUF, so we
 +    # set the size of an encoded chunk to be PIPE_BUF - 128 to leave some space
 +    # for the command.
 +    chunk_size="$(expr "$pipe_buf" - 128)"
 +fi
 +
 +# Check if the image format is supported.
 +is_format_supported() {
 +    arg_format="$1"
 +    if [ "$arg_format" = "PNG" ]; then
 +        return 0
 +    elif [ "$arg_format" = "JPEG" ]; then
 +        if [ -z "$inside_tmux" ]; then
 +            actual_term="$TERM"
 +        else
 +            # Get the actual current terminal name from tmux.
 +            actual_term="$(tmux display-message -p "#{client_termname}")"
 +        fi
 +        # st is known to support JPEG.
 +        case "$actual_term" in
 +            st | *-st | st-* | *-st-*)
 +                return 0
 +                ;;
 +        esac
 +        return 1
 +    else
 +        return 1
 +    fi
 +}
 +
 +# Send an uploading command. Usage: gr_upload <action> <command> <file>
 +# Where <action> is a part of command that specifies the action, it will be
 +# repeated for every chunk (if the method is direct), and <command> is the rest
 +# of the command that specifies the image parameters. <action> and <command>
 +# must not include the transmission method or ';'.
 +# Example:
 +# gr_upload "a=T,q=2" "U=1,i=${image_id},f=100,c=${cols},r=${rows}" "$file"
 +gr_upload() {
 +    arg_action="$1"
 +    arg_command="$2"
 +    arg_file="$3"
 +    if [ "$uploading_method" = "file" ]; then
 +        # base64-encode the filename
 +        encoded_filename=$(printf '%s' "$arg_file" | base64 -w0)
 +        # If the file name contains 'tty-graphics-protocol', assume it's
 +        # temporary and use t=t.
 +        medium="t=f"
 +        case "$arg_file" in
 +            *tty-graphics-protocol*)
 +                medium="t=t"
 +                ;;
 +            *)
 +                medium="t=f"
 +                ;;
 +        esac
 +        gr_command "${arg_action},${arg_command},${medium};${encoded_filename}"
 +    fi
 +    if [ "$uploading_method" = "direct" ]; then
 +        # Create a temporary directory to store the chunked image.
 +        chunkdir="$(mktemp -d)"
 +        if [ ! "$chunkdir" ] || [ ! -d "$chunkdir" ]; then
 +            echo "Can't create a temp dir" >&2
 +            exit 1
 +        fi
 +        # base64-encode the file and split it into chunks. The size of each
 +        # graphics command shouldn't be more than 4096, so we set the size of an
 +        # encoded chunk to be 3968, slightly less than that.
 +        chunk_size=3968
 +        cat "$arg_file" | base64 -w0 | split -b "$chunk_size" - "$chunkdir/chunk_"
 +
 +        # Issue a command indicating that we want to start data transmission for
 +        # a new image.
 +        gr_command "${arg_action},${arg_command},t=d,m=1"
 +
 +        # Transmit chunks.
 +        for chunk in "$chunkdir/chunk_"*; do
 +            gr_command "${arg_action},i=${image_id},m=1;$(cat "$chunk")"
 +            rm "$chunk"
 +        done
 +
 +        # Tell the terminal that we are done.
 +        gr_command "${arg_action},i=$image_id,m=0"
 +
 +        # Remove the temporary directory.
 +        rmdir "$chunkdir"
 +    fi
 +}
 +
 +delayed_frame_dir_cleanup() {
 +    arg_frame_dir="$1"
 +    sleep 2
 +    if [ -n "$arg_frame_dir" ]; then
 +        for frame in "$arg_frame_dir"/frame_*.png; do
 +            rm "$frame"
 +        done
 +        rmdir "$arg_frame_dir"
 +    fi
 +}
 +
 +upload_image_and_print_placeholder() {
 +    # Check if the file is an animation.
 +    format_output=$($identify -format '%n %m\n' "$file" | head -n 1)
 +    frame_count="$(printf '%s' "$format_output" | cut -d ' ' -f 1)"
 +    image_format="$(printf '%s' "$format_output" | cut -d ' ' -f 2)"
 +
 +    if [ "$frame_count" -gt 1 ]; then
 +        # The file is an animation, decompose into frames and upload each frame.
 +        frame_dir="$(mktemp -d)"
 +        frame_dir="$HOME/temp/frames${frame_dir}"
 +        mkdir -p "$frame_dir"
 +        if [ ! "$frame_dir" ] || [ ! -d "$frame_dir" ]; then
 +            echo "Can't create a temp dir for frames" >&2
 +            exit 1
 +        fi
 +
 +        # Decompose the animation into separate frames.
 +        $convert "$file" -coalesce "$frame_dir/frame_%06d.png"
 +
 +        # Get all frame delays at once, in centiseconds, as a space-separated
 +        # string.
 +        delays=$($identify -format "%T " "$file")
 +
 +        frame_number=1
 +        for frame in "$frame_dir"/frame_*.png; do
 +            # Read the delay for the current frame and convert it from
 +            # centiseconds to milliseconds.
 +            delay=$(printf '%s' "$delays" | cut -d ' ' -f "$frame_number")
 +            delay=$((delay * 10))
 +            # If the delay is 0, set it to 100ms.
 +            if [ "$delay" -eq 0 ]; then
 +                delay=100
 +            fi
 +
 +            if [ -n "$speed" ]; then
 +                delay=$(bc_round "$delay / $speed")
 +            fi
 +
 +            if [ "$frame_number" -eq 1 ]; then
 +                # Abort the previous transmission, just in case.
 +                gr_command "q=2,a=t,i=${image_id},m=0"
 +                # Upload the first frame with a=T
 +                gr_upload "q=2,a=T" "f=100,U=1,i=${image_id},c=${cols},r=${rows}" "$frame"
 +                # Set the delay for the first frame and also play the animation
 +                # in loading mode (s=2).
 +                gr_command "a=a,v=1,s=2,r=${frame_number},z=${delay},i=${image_id}"
 +                # Print the placeholder after the first frame to reduce the wait
 +                # time.
 +                print_placeholder
 +            else
 +                # Upload subsequent frames with a=f
 +                gr_upload "q=2,a=f" "f=100,i=${image_id},z=${delay}" "$frame"
 +            fi
 +
 +            frame_number=$((frame_number + 1))
 +        done
 +
 +        # Play the animation in loop mode (s=3).
 +        gr_command "a=a,v=1,s=3,i=${image_id}"
 +
 +        # Remove the temporary directory, but do it in the background with a
 +        # delay to avoid removing files before they are loaded by the terminal.
 +        delayed_frame_dir_cleanup "$frame_dir" 2> /dev/null &
 +    elif is_format_supported "$image_format"; then
 +        # The file is not an animation and has a supported format, upload it
 +        # directly.
 +        gr_upload "q=2,a=T" "U=1,i=${image_id},f=100,c=${cols},r=${rows}" "$file"
 +        # Print the placeholder
 +        print_placeholder
 +    else
 +        # The format is not supported, try to convert it to png.
 +        temp_file="$(mktemp --tmpdir "icat-mini-tty-graphics-protocol-XXXXX.png")"
 +        if ! $convert "$file" "$temp_file"; then
 +            echo "Failed to convert the image to PNG" >&2
 +            exit 1
 +        fi
 +        # Upload the converted image.
 +        gr_upload "q=2,a=T" "U=1,i=${image_id},f=100,c=${cols},r=${rows}" "$temp_file"
 +        # Print the placeholder
 +        print_placeholder
 +    fi
 +}
 +
 +#####################################################################
 +# Printing the image placeholder
 +#####################################################################
 +
 +print_placeholder() {
 +    # Each line starts with the escape sequence to set the foreground color to
 +    # the image id.
 +    blue="$(expr "$image_id" % 256 )"
 +    green="$(expr \( "$image_id" / 256 \) % 256 )"
 +    red="$(expr \( "$image_id" / 65536 \) % 256 )"
 +    line_start="$(printf "\e[38;2;%d;%d;%dm" "$red" "$green" "$blue")"
 +    line_end="$(printf "\e[39;m")"
 +
 +    id4th="$(expr \( "$image_id" / 16777216 \) % 256 )"
 +    eval "id_diacritic=\$d${id4th}"
 +
 +    # Reset the brush state, mostly to reset the underline color.
 +    printf "\e[0m"
 +
 +    # Fill the output with characters representing the image
 +    for y in $(seq 0 "$(expr "$rows" - 1)"); do
 +        eval "row_diacritic=\$d${y}"
 +        line="$line_start"
 +        for x in $(seq 0 "$(expr "$cols" - 1)"); do
 +            eval "col_diacritic=\$d${x}"
 +            # Note that when $x is out of bounds, the column diacritic will
 +            # be empty, meaning that the column should be guessed by the
 +            # terminal.
 +            if [ "$x" -ge "$num_diacritics" ]; then
 +                line="${line}${placeholder}${row_diacritic}"
 +            else
 +                line="${line}${placeholder}${row_diacritic}${col_diacritic}${id_diacritic}"
 +            fi
 +        done
 +        line="${line}${line_end}"
 +        printf "%s\n" "$line"
 +    done
 +
 +    printf "\e[0m"
 +}
 +
 +d0="̅"
 +d1="̍"
 +d2="̎"
 +d3="̐"
 +d4="̒"
 +d5="̽"
 +d6="̾"
 +d7="̿"
 +d8="͆"
 +d9="͊"
 +d10="͋"
 +d11="͌"
 +d12="͐"
 +d13="͑"
 +d14="͒"
 +d15="͗"
 +d16="͛"
 +d17="ͣ"
 +d18="ͤ"
 +d19="ͥ"
 +d20="ͦ"
 +d21="ͧ"
 +d22="ͨ"
 +d23="ͩ"
 +d24="ͪ"
 +d25="ͫ"
 +d26="ͬ"
 +d27="ͭ"
 +d28="ͮ"
 +d29="ͯ"
 +d30="҃"
 +d31="҄"
 +d32="҅"
 +d33="҆"
 +d34="҇"
 +d35="֒"
 +d36="֓"
 +d37="֔"
 +d38="֕"
 +d39="֗"
 +d40="֘"
 +d41="֙"
 +d42="֜"
 +d43="֝"
 +d44="֞"
 +d45="֟"
 +d46="֠"
 +d47="֡"
 +d48="֨"
 +d49="֩"
 +d50="֫"
 +d51="֬"
 +d52="֯"
 +d53="ׄ"
 +d54="ؐ"
 +d55="ؑ"
 +d56="ؒ"
 +d57="ؓ"
 +d58="ؔ"
 +d59="ؕ"
 +d60="ؖ"
 +d61="ؗ"
 +d62="ٗ"
 +d63="٘"
 +d64="ٙ"
 +d65="ٚ"
 +d66="ٛ"
 +d67="ٝ"
 +d68="ٞ"
 +d69="ۖ"
 +d70="ۗ"
 +d71="ۘ"
 +d72="ۙ"
 +d73="ۚ"
 +d74="ۛ"
 +d75="ۜ"
 +d76="۟"
 +d77="۠"
 +d78="ۡ"
 +d79="ۢ"
 +d80="ۤ"
 +d81="ۧ"
 +d82="ۨ"
 +d83="۫"
 +d84="۬"
 +d85="ܰ"
 +d86="ܲ"
 +d87="ܳ"
 +d88="ܵ"
 +d89="ܶ"
 +d90="ܺ"
 +d91="ܽ"
 +d92="ܿ"
 +d93="݀"
 +d94="݁"
 +d95="݃"
 +d96="݅"
 +d97="݇"
 +d98="݉"
 +d99="݊"
 +d100="߫"
 +d101="߬"
 +d102="߭"
 +d103="߮"
 +d104="߯"
 +d105="߰"
 +d106="߱"
 +d107="߳"
 +d108="ࠖ"
 +d109="ࠗ"
 +d110="࠘"
 +d111="࠙"
 +d112="ࠛ"
 +d113="ࠜ"
 +d114="ࠝ"
 +d115="ࠞ"
 +d116="ࠟ"
 +d117="ࠠ"
 +d118="ࠡ"
 +d119="ࠢ"
 +d120="ࠣ"
 +d121="ࠥ"
 +d122="ࠦ"
 +d123="ࠧ"
 +d124="ࠩ"
 +d125="ࠪ"
 +d126="ࠫ"
 +d127="ࠬ"
 +d128="࠭"
 +d129="॑"
 +d130="॓"
 +d131="॔"
 +d132="ྂ"
 +d133="ྃ"
 +d134="྆"
 +d135="྇"
 +d136="፝"
 +d137="፞"
 +d138="፟"
 +d139="៝"
 +d140="᤺"
 +d141="ᨗ"
 +d142="᩵"
 +d143="᩶"
 +d144="᩷"
 +d145="᩸"
 +d146="᩹"
 +d147="᩺"
 +d148="᩻"
 +d149="᩼"
 +d150="᭫"
 +d151="᭭"
 +d152="᭮"
 +d153="᭯"
 +d154="᭰"
 +d155="᭱"
 +d156="᭲"
 +d157="᭳"
 +d158="᳐"
 +d159="᳑"
 +d160="᳒"
 +d161="᳚"
 +d162="᳛"
 +d163="᳠"
 +d164="᷀"
 +d165="᷁"
 +d166="᷃"
 +d167="᷄"
 +d168="᷅"
 +d169="᷆"
 +d170="᷇"
 +d171="᷈"
 +d172="᷉"
 +d173="᷋"
 +d174="᷌"
 +d175="᷑"
 +d176="᷒"
 +d177="ᷓ"
 +d178="ᷔ"
 +d179="ᷕ"
 +d180="ᷖ"
 +d181="ᷗ"
 +d182="ᷘ"
 +d183="ᷙ"
 +d184="ᷚ"
 +d185="ᷛ"
 +d186="ᷜ"
 +d187="ᷝ"
 +d188="ᷞ"
 +d189="ᷟ"
 +d190="ᷠ"
 +d191="ᷡ"
 +d192="ᷢ"
 +d193="ᷣ"
 +d194="ᷤ"
 +d195="ᷥ"
 +d196="ᷦ"
 +d197="᷾"
 +d198="⃐"
 +d199="⃑"
 +d200="⃔"
 +d201="⃕"
 +d202="⃖"
 +d203="⃗"
 +d204="⃛"
 +d205="⃜"
 +d206="⃡"
 +d207="⃧"
 +d208="⃩"
 +d209="⃰"
 +d210="⳯"
 +d211="⳰"
 +d212="⳱"
 +d213="ⷠ"
 +d214="ⷡ"
 +d215="ⷢ"
 +d216="ⷣ"
 +d217="ⷤ"
 +d218="ⷥ"
 +d219="ⷦ"
 +d220="ⷧ"
 +d221="ⷨ"
 +d222="ⷩ"
 +d223="ⷪ"
 +d224="ⷫ"
 +d225="ⷬ"
 +d226="ⷭ"
 +d227="ⷮ"
 +d228="ⷯ"
 +d229="ⷰ"
 +d230="ⷱ"
 +d231="ⷲ"
 +d232="ⷳ"
 +d233="ⷴ"
 +d234="ⷵ"
 +d235="ⷶ"
 +d236="ⷷ"
 +d237="ⷸ"
 +d238="ⷹ"
 +d239="ⷺ"
 +d240="ⷻ"
 +d241="ⷼ"
 +d242="ⷽ"
 +d243="ⷾ"
 +d244="ⷿ"
 +d245="꙯"
 +d246="꙼"
 +d247="꙽"
 +d248="꛰"
 +d249="꛱"
 +d250="꣠"
 +d251="꣡"
 +d252="꣢"
 +d253="꣣"
 +d254="꣤"
 +d255="꣥"
 +d256="꣦"
 +d257="꣧"
 +d258="꣨"
 +d259="꣩"
 +d260="꣪"
 +d261="꣫"
 +d262="꣬"
 +d263="꣭"
 +d264="꣮"
 +d265="꣯"
 +d266="꣰"
 +d267="꣱"
 +d268="ꪰ"
 +d269="ꪲ"
 +d270="ꪳ"
 +d271="ꪷ"
 +d272="ꪸ"
 +d273="ꪾ"
 +d274="꪿"
 +d275="꫁"
 +d276="︠"
 +d277="︡"
 +d278="︢"
 +d279="︣"
 +d280="︤"
 +d281="︥"
 +d282="︦"
 +d283="𐨏"
 +d284="𐨸"
 +d285="𝆅"
 +d286="𝆆"
 +d287="𝆇"
 +d288="𝆈"
 +d289="𝆉"
 +d290="𝆪"
 +d291="𝆫"
 +d292="𝆬"
 +d293="𝆭"
 +d294="𝉂"
 +d295="𝉃"
 +d296="𝉄"
 +
 +num_diacritics="297"
 +
 +placeholder="􎻮"
 +
 +#####################################################################
 +# Upload the image and print the placeholder
 +#####################################################################
 +
 +upload_image_and_print_placeholder
 diff --git a/khash.h b/khash.h
 new file mode 100644
 index 0000000..f75f347
 --- /dev/null
 +++ b/khash.h
 @@ -0,0 +1,627 @@
 +/* The MIT License
 +
 +   Copyright (c) 2008, 2009, 2011 by Attractive Chaos <attractor@live.co.uk>
 +
 +   Permission is hereby granted, free of charge, to any person obtaining
 +   a copy of this software and associated documentation files (the
 +   "Software"), to deal in the Software without restriction, including
 +   without limitation the rights to use, copy, modify, merge, publish,
 +   distribute, sublicense, and/or sell copies of the Software, and to
 +   permit persons to whom the Software is furnished to do so, subject to
 +   the following conditions:
 +
 +   The above copyright notice and this permission notice shall be
 +   included in all copies or substantial portions of the Software.
 +
 +   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 +   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 +   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 +   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 +   BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 +   ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 +   CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 +   SOFTWARE.
 +*/
 +
 +/*
 +  An example:
 +
 +#include "khash.h"
 +KHASH_MAP_INIT_INT(32, char)
 +int main() {
 +	int ret, is_missing;
 +	khiter_t k;
 +	khash_t(32) *h = kh_init(32);
 +	k = kh_put(32, h, 5, &ret);
 +	kh_value(h, k) = 10;
 +	k = kh_get(32, h, 10);
 +	is_missing = (k == kh_end(h));
 +	k = kh_get(32, h, 5);
 +	kh_del(32, h, k);
 +	for (k = kh_begin(h); k != kh_end(h); ++k)
 +		if (kh_exist(h, k)) kh_value(h, k) = 1;
 +	kh_destroy(32, h);
 +	return 0;
 +}
 +*/
 +
 +/*
 +  2013-05-02 (0.2.8):
 +
 +	* Use quadratic probing. When the capacity is power of 2, stepping function
 +	  i*(i+1)/2 guarantees to traverse each bucket. It is better than double
 +	  hashing on cache performance and is more robust than linear probing.
 +
 +	  In theory, double hashing should be more robust than quadratic probing.
 +	  However, my implementation is probably not for large hash tables, because
 +	  the second hash function is closely tied to the first hash function,
 +	  which reduce the effectiveness of double hashing.
 +
 +	Reference: http://research.cs.vt.edu/AVresearch/hashing/quadratic.php
 +
 +  2011-12-29 (0.2.7):
 +
 +    * Minor code clean up; no actual effect.
 +
 +  2011-09-16 (0.2.6):
 +
 +	* The capacity is a power of 2. This seems to dramatically improve the
 +	  speed for simple keys. Thank Zilong Tan for the suggestion. Reference:
 +
 +	   - http://code.google.com/p/ulib/
 +	   - http://nothings.org/computer/judy/
 +
 +	* Allow to optionally use linear probing which usually has better
 +	  performance for random input. Double hashing is still the default as it
 +	  is more robust to certain non-random input.
 +
 +	* Added Wang's integer hash function (not used by default). This hash
 +	  function is more robust to certain non-random input.
 +
 +  2011-02-14 (0.2.5):
 +
 +    * Allow to declare global functions.
 +
 +  2009-09-26 (0.2.4):
 +
 +    * Improve portability
 +
 +  2008-09-19 (0.2.3):
 +
 +	* Corrected the example
 +	* Improved interfaces
 +
 +  2008-09-11 (0.2.2):
 +
 +	* Improved speed a little in kh_put()
 +
 +  2008-09-10 (0.2.1):
 +
 +	* Added kh_clear()
 +	* Fixed a compiling error
 +
 +  2008-09-02 (0.2.0):
 +
 +	* Changed to token concatenation which increases flexibility.
 +
 +  2008-08-31 (0.1.2):
 +
 +	* Fixed a bug in kh_get(), which has not been tested previously.
 +
 +  2008-08-31 (0.1.1):
 +
 +	* Added destructor
 +*/
 +
 +
 +#ifndef __AC_KHASH_H
 +#define __AC_KHASH_H
 +
 +/*!
 +  @header
 +
 +  Generic hash table library.
 + */
 +
 +#define AC_VERSION_KHASH_H "0.2.8"
 +
 +#include <stdlib.h>
 +#include <string.h>
 +#include <limits.h>
 +
 +/* compiler specific configuration */
 +
 +#if UINT_MAX == 0xffffffffu
 +typedef unsigned int khint32_t;
 +#elif ULONG_MAX == 0xffffffffu
 +typedef unsigned long khint32_t;
 +#endif
 +
 +#if ULONG_MAX == ULLONG_MAX
 +typedef unsigned long khint64_t;
 +#else
 +typedef unsigned long long khint64_t;
 +#endif
 +
 +#ifndef kh_inline
 +#ifdef _MSC_VER
 +#define kh_inline __inline
 +#else
 +#define kh_inline inline
 +#endif
 +#endif /* kh_inline */
 +
 +#ifndef klib_unused
 +#if (defined __clang__ && __clang_major__ >= 3) || (defined __GNUC__ && __GNUC__ >= 3)
 +#define klib_unused __attribute__ ((__unused__))
 +#else
 +#define klib_unused
 +#endif
 +#endif /* klib_unused */
 +
 +typedef khint32_t khint_t;
 +typedef khint_t khiter_t;
 +
 +#define __ac_isempty(flag, i) ((flag[i>>4]>>((i&0xfU)<<1))&2)
 +#define __ac_isdel(flag, i) ((flag[i>>4]>>((i&0xfU)<<1))&1)
 +#define __ac_iseither(flag, i) ((flag[i>>4]>>((i&0xfU)<<1))&3)
 +#define __ac_set_isdel_false(flag, i) (flag[i>>4]&=~(1ul<<((i&0xfU)<<1)))
 +#define __ac_set_isempty_false(flag, i) (flag[i>>4]&=~(2ul<<((i&0xfU)<<1)))
 +#define __ac_set_isboth_false(flag, i) (flag[i>>4]&=~(3ul<<((i&0xfU)<<1)))
 +#define __ac_set_isdel_true(flag, i) (flag[i>>4]|=1ul<<((i&0xfU)<<1))
 +
 +#define __ac_fsize(m) ((m) < 16? 1 : (m)>>4)
 +
 +#ifndef kroundup32
 +#define kroundup32(x) (--(x), (x)|=(x)>>1, (x)|=(x)>>2, (x)|=(x)>>4, (x)|=(x)>>8, (x)|=(x)>>16, ++(x))
 +#endif
 +
 +#ifndef kcalloc
 +#define kcalloc(N,Z) calloc(N,Z)
 +#endif
 +#ifndef kmalloc
 +#define kmalloc(Z) malloc(Z)
 +#endif
 +#ifndef krealloc
 +#define krealloc(P,Z) realloc(P,Z)
 +#endif
 +#ifndef kfree
 +#define kfree(P) free(P)
 +#endif
 +
 +static const double __ac_HASH_UPPER = 0.77;
 +
 +#define __KHASH_TYPE(name, khkey_t, khval_t) \
 +	typedef struct kh_##name##_s { \
 +		khint_t n_buckets, size, n_occupied, upper_bound; \
 +		khint32_t *flags; \
 +		khkey_t *keys; \
 +		khval_t *vals; \
 +	} kh_##name##_t;
 +
 +#define __KHASH_PROTOTYPES(name, khkey_t, khval_t)	 					\
 +	extern kh_##name##_t *kh_init_##name(void);							\
 +	extern void kh_destroy_##name(kh_##name##_t *h);					\
 +	extern void kh_clear_##name(kh_##name##_t *h);						\
 +	extern khint_t kh_get_##name(const kh_##name##_t *h, khkey_t key); 	\
 +	extern int kh_resize_##name(kh_##name##_t *h, khint_t new_n_buckets); \
 +	extern khint_t kh_put_##name(kh_##name##_t *h, khkey_t key, int *ret); \
 +	extern void kh_del_##name(kh_##name##_t *h, khint_t x);
 +
 +#define __KHASH_IMPL(name, SCOPE, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal) \
 +	SCOPE kh_##name##_t *kh_init_##name(void) {							\
 +		return (kh_##name##_t*)kcalloc(1, sizeof(kh_##name##_t));		\
 +	}																	\
 +	SCOPE void kh_destroy_##name(kh_##name##_t *h)						\
 +	{																	\
 +		if (h) {														\
 +			kfree((void *)h->keys); kfree(h->flags);					\
 +			kfree((void *)h->vals);										\
 +			kfree(h);													\
 +		}																\
 +	}																	\
 +	SCOPE void kh_clear_##name(kh_##name##_t *h)						\
 +	{																	\
 +		if (h && h->flags) {											\
 +			memset(h->flags, 0xaa, __ac_fsize(h->n_buckets) * sizeof(khint32_t)); \
 +			h->size = h->n_occupied = 0;								\
 +		}																\
 +	}																	\
 +	SCOPE khint_t kh_get_##name(const kh_##name##_t *h, khkey_t key) 	\
 +	{																	\
 +		if (h->n_buckets) {												\
 +			khint_t k, i, last, mask, step = 0; \
 +			mask = h->n_buckets - 1;									\
 +			k = __hash_func(key); i = k & mask;							\
 +			last = i; \
 +			while (!__ac_isempty(h->flags, i) && (__ac_isdel(h->flags, i) || !__hash_equal(h->keys[i], key))) { \
 +				i = (i + (++step)) & mask; \
 +				if (i == last) return h->n_buckets;						\
 +			}															\
 +			return __ac_iseither(h->flags, i)? h->n_buckets : i;		\
 +		} else return 0;												\
 +	}																	\
 +	SCOPE int kh_resize_##name(kh_##name##_t *h, khint_t new_n_buckets) \
 +	{ /* This function uses 0.25*n_buckets bytes of working space instead of [sizeof(key_t+val_t)+.25]*n_buckets. */ \
 +		khint32_t *new_flags = 0;										\
 +		khint_t j = 1;													\
 +		{																\
 +			kroundup32(new_n_buckets); 									\
 +			if (new_n_buckets < 4) new_n_buckets = 4;					\
 +			if (h->size >= (khint_t)(new_n_buckets * __ac_HASH_UPPER + 0.5)) j = 0;	/* requested size is too small */ \
 +			else { /* hash table size to be changed (shrink or expand); rehash */ \
 +				new_flags = (khint32_t*)kmalloc(__ac_fsize(new_n_buckets) * sizeof(khint32_t));	\
 +				if (!new_flags) return -1;								\
 +				memset(new_flags, 0xaa, __ac_fsize(new_n_buckets) * sizeof(khint32_t)); \
 +				if (h->n_buckets < new_n_buckets) {	/* expand */		\
 +					khkey_t *new_keys = (khkey_t*)krealloc((void *)h->keys, new_n_buckets * sizeof(khkey_t)); \
 +					if (!new_keys) { kfree(new_flags); return -1; }		\
 +					h->keys = new_keys;									\
 +					if (kh_is_map) {									\
 +						khval_t *new_vals = (khval_t*)krealloc((void *)h->vals, new_n_buckets * sizeof(khval_t)); \
 +						if (!new_vals) { kfree(new_flags); return -1; }	\
 +						h->vals = new_vals;								\
 +					}													\
 +				} /* otherwise shrink */								\
 +			}															\
 +		}																\
 +		if (j) { /* rehashing is needed */								\
 +			for (j = 0; j != h->n_buckets; ++j) {						\
 +				if (__ac_iseither(h->flags, j) == 0) {					\
 +					khkey_t key = h->keys[j];							\
 +					khval_t val;										\
 +					khint_t new_mask;									\
 +					new_mask = new_n_buckets - 1; 						\
 +					if (kh_is_map) val = h->vals[j];					\
 +					__ac_set_isdel_true(h->flags, j);					\
 +					while (1) { /* kick-out process; sort of like in Cuckoo hashing */ \
 +						khint_t k, i, step = 0; \
 +						k = __hash_func(key);							\
 +						i = k & new_mask;								\
 +						while (!__ac_isempty(new_flags, i)) i = (i + (++step)) & new_mask; \
 +						__ac_set_isempty_false(new_flags, i);			\
 +						if (i < h->n_buckets && __ac_iseither(h->flags, i) == 0) { /* kick out the existing element */ \
 +							{ khkey_t tmp = h->keys[i]; h->keys[i] = key; key = tmp; } \
 +							if (kh_is_map) { khval_t tmp = h->vals[i]; h->vals[i] = val; val = tmp; } \
 +							__ac_set_isdel_true(h->flags, i); /* mark it as deleted in the old hash table */ \
 +						} else { /* write the element and jump out of the loop */ \
 +							h->keys[i] = key;							\
 +							if (kh_is_map) h->vals[i] = val;			\
 +							break;										\
 +						}												\
 +					}													\
 +				}														\
 +			}															\
 +			if (h->n_buckets > new_n_buckets) { /* shrink the hash table */ \
 +				h->keys = (khkey_t*)krealloc((void *)h->keys, new_n_buckets * sizeof(khkey_t)); \
 +				if (kh_is_map) h->vals = (khval_t*)krealloc((void *)h->vals, new_n_buckets * sizeof(khval_t)); \
 +			}															\
 +			kfree(h->flags); /* free the working space */				\
 +			h->flags = new_flags;										\
 +			h->n_buckets = new_n_buckets;								\
 +			h->n_occupied = h->size;									\
 +			h->upper_bound = (khint_t)(h->n_buckets * __ac_HASH_UPPER + 0.5); \
 +		}																\
 +		return 0;														\
 +	}																	\
 +	SCOPE khint_t kh_put_##name(kh_##name##_t *h, khkey_t key, int *ret) \
 +	{																	\
 +		khint_t x;														\
 +		if (h->n_occupied >= h->upper_bound) { /* update the hash table */ \
 +			if (h->n_buckets > (h->size<<1)) {							\
 +				if (kh_resize_##name(h, h->n_buckets - 1) < 0) { /* clear "deleted" elements */ \
 +					*ret = -1; return h->n_buckets;						\
 +				}														\
 +			} else if (kh_resize_##name(h, h->n_buckets + 1) < 0) { /* expand the hash table */ \
 +				*ret = -1; return h->n_buckets;							\
 +			}															\
 +		} /* TODO: to implement automatically shrinking; resize() already support shrinking */ \
 +		{																\
 +			khint_t k, i, site, last, mask = h->n_buckets - 1, step = 0; \
 +			x = site = h->n_buckets; k = __hash_func(key); i = k & mask; \
 +			if (__ac_isempty(h->flags, i)) x = i; /* for speed up */	\
 +			else {														\
 +				last = i; \
 +				while (!__ac_isempty(h->flags, i) && (__ac_isdel(h->flags, i) || !__hash_equal(h->keys[i], key))) { \
 +					if (__ac_isdel(h->flags, i)) site = i;				\
 +					i = (i + (++step)) & mask; \
 +					if (i == last) { x = site; break; }					\
 +				}														\
 +				if (x == h->n_buckets) {								\
 +					if (__ac_isempty(h->flags, i) && site != h->n_buckets) x = site; \
 +					else x = i;											\
 +				}														\
 +			}															\
 +		}																\
 +		if (__ac_isempty(h->flags, x)) { /* not present at all */		\
 +			h->keys[x] = key;											\
 +			__ac_set_isboth_false(h->flags, x);							\
 +			++h->size; ++h->n_occupied;									\
 +			*ret = 1;													\
 +		} else if (__ac_isdel(h->flags, x)) { /* deleted */				\
 +			h->keys[x] = key;											\
 +			__ac_set_isboth_false(h->flags, x);							\
 +			++h->size;													\
 +			*ret = 2;													\
 +		} else *ret = 0; /* Don't touch h->keys[x] if present and not deleted */ \
 +		return x;														\
 +	}																	\
 +	SCOPE void kh_del_##name(kh_##name##_t *h, khint_t x)				\
 +	{																	\
 +		if (x != h->n_buckets && !__ac_iseither(h->flags, x)) {			\
 +			__ac_set_isdel_true(h->flags, x);							\
 +			--h->size;													\
 +		}																\
 +	}
 +
 +#define KHASH_DECLARE(name, khkey_t, khval_t)		 					\
 +	__KHASH_TYPE(name, khkey_t, khval_t) 								\
 +	__KHASH_PROTOTYPES(name, khkey_t, khval_t)
 +
 +#define KHASH_INIT2(name, SCOPE, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal) \
 +	__KHASH_TYPE(name, khkey_t, khval_t) 								\
 +	__KHASH_IMPL(name, SCOPE, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal)
 +
 +#define KHASH_INIT(name, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal) \
 +	KHASH_INIT2(name, static kh_inline klib_unused, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal)
 +
 +/* --- BEGIN OF HASH FUNCTIONS --- */
 +
 +/*! @function
 +  @abstract     Integer hash function
 +  @param  key   The integer [khint32_t]
 +  @return       The hash value [khint_t]
 + */
 +#define kh_int_hash_func(key) (khint32_t)(key)
 +/*! @function
 +  @abstract     Integer comparison function
 + */
 +#define kh_int_hash_equal(a, b) ((a) == (b))
 +/*! @function
 +  @abstract     64-bit integer hash function
 +  @param  key   The integer [khint64_t]
 +  @return       The hash value [khint_t]
 + */
 +#define kh_int64_hash_func(key) (khint32_t)((key)>>33^(key)^(key)<<11)
 +/*! @function
 +  @abstract     64-bit integer comparison function
 + */
 +#define kh_int64_hash_equal(a, b) ((a) == (b))
 +/*! @function
 +  @abstract     const char* hash function
 +  @param  s     Pointer to a null terminated string
 +  @return       The hash value
 + */
 +static kh_inline khint_t __ac_X31_hash_string(const char *s)
 +{
 +	khint_t h = (khint_t)*s;
 +	if (h) for (++s ; *s; ++s) h = (h << 5) - h + (khint_t)*s;
 +	return h;
 +}
 +/*! @function
 +  @abstract     Another interface to const char* hash function
 +  @param  key   Pointer to a null terminated string [const char*]
 +  @return       The hash value [khint_t]
 + */
 +#define kh_str_hash_func(key) __ac_X31_hash_string(key)
 +/*! @function
 +  @abstract     Const char* comparison function
 + */
 +#define kh_str_hash_equal(a, b) (strcmp(a, b) == 0)
 +
 +static kh_inline khint_t __ac_Wang_hash(khint_t key)
 +{
 +    key += ~(key << 15);
 +    key ^=  (key >> 10);
 +    key +=  (key << 3);
 +    key ^=  (key >> 6);
 +    key += ~(key << 11);
 +    key ^=  (key >> 16);
 +    return key;
 +}
 +#define kh_int_hash_func2(key) __ac_Wang_hash((khint_t)key)
 +
 +/* --- END OF HASH FUNCTIONS --- */
 +
 +/* Other convenient macros... */
 +
 +/*!
 +  @abstract Type of the hash table.
 +  @param  name  Name of the hash table [symbol]
 + */
 +#define khash_t(name) kh_##name##_t
 +
 +/*! @function
 +  @abstract     Initiate a hash table.
 +  @param  name  Name of the hash table [symbol]
 +  @return       Pointer to the hash table [khash_t(name)*]
 + */
 +#define kh_init(name) kh_init_##name()
 +
 +/*! @function
 +  @abstract     Destroy a hash table.
 +  @param  name  Name of the hash table [symbol]
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 + */
 +#define kh_destroy(name, h) kh_destroy_##name(h)
 +
 +/*! @function
 +  @abstract     Reset a hash table without deallocating memory.
 +  @param  name  Name of the hash table [symbol]
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 + */
 +#define kh_clear(name, h) kh_clear_##name(h)
 +
 +/*! @function
 +  @abstract     Resize a hash table.
 +  @param  name  Name of the hash table [symbol]
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 +  @param  s     New size [khint_t]
 + */
 +#define kh_resize(name, h, s) kh_resize_##name(h, s)
 +
 +/*! @function
 +  @abstract     Insert a key to the hash table.
 +  @param  name  Name of the hash table [symbol]
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 +  @param  k     Key [type of keys]
 +  @param  r     Extra return code: -1 if the operation failed;
 +                0 if the key is present in the hash table;
 +                1 if the bucket is empty (never used); 2 if the element in
 +				the bucket has been deleted [int*]
 +  @return       Iterator to the inserted element [khint_t]
 + */
 +#define kh_put(name, h, k, r) kh_put_##name(h, k, r)
 +
 +/*! @function
 +  @abstract     Retrieve a key from the hash table.
 +  @param  name  Name of the hash table [symbol]
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 +  @param  k     Key [type of keys]
 +  @return       Iterator to the found element, or kh_end(h) if the element is absent [khint_t]
 + */
 +#define kh_get(name, h, k) kh_get_##name(h, k)
 +
 +/*! @function
 +  @abstract     Remove a key from the hash table.
 +  @param  name  Name of the hash table [symbol]
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 +  @param  k     Iterator to the element to be deleted [khint_t]
 + */
 +#define kh_del(name, h, k) kh_del_##name(h, k)
 +
 +/*! @function
 +  @abstract     Test whether a bucket contains data.
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 +  @param  x     Iterator to the bucket [khint_t]
 +  @return       1 if containing data; 0 otherwise [int]
 + */
 +#define kh_exist(h, x) (!__ac_iseither((h)->flags, (x)))
 +
 +/*! @function
 +  @abstract     Get key given an iterator
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 +  @param  x     Iterator to the bucket [khint_t]
 +  @return       Key [type of keys]
 + */
 +#define kh_key(h, x) ((h)->keys[x])
 +
 +/*! @function
 +  @abstract     Get value given an iterator
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 +  @param  x     Iterator to the bucket [khint_t]
 +  @return       Value [type of values]
 +  @discussion   For hash sets, calling this results in segfault.
 + */
 +#define kh_val(h, x) ((h)->vals[x])
 +
 +/*! @function
 +  @abstract     Alias of kh_val()
 + */
 +#define kh_value(h, x) ((h)->vals[x])
 +
 +/*! @function
 +  @abstract     Get the start iterator
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 +  @return       The start iterator [khint_t]
 + */
 +#define kh_begin(h) (khint_t)(0)
 +
 +/*! @function
 +  @abstract     Get the end iterator
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 +  @return       The end iterator [khint_t]
 + */
 +#define kh_end(h) ((h)->n_buckets)
 +
 +/*! @function
 +  @abstract     Get the number of elements in the hash table
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 +  @return       Number of elements in the hash table [khint_t]
 + */
 +#define kh_size(h) ((h)->size)
 +
 +/*! @function
 +  @abstract     Get the number of buckets in the hash table
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 +  @return       Number of buckets in the hash table [khint_t]
 + */
 +#define kh_n_buckets(h) ((h)->n_buckets)
 +
 +/*! @function
 +  @abstract     Iterate over the entries in the hash table
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 +  @param  kvar  Variable to which key will be assigned
 +  @param  vvar  Variable to which value will be assigned
 +  @param  code  Block of code to execute
 + */
 +#define kh_foreach(h, kvar, vvar, code) { khint_t __i;		\
 +	for (__i = kh_begin(h); __i != kh_end(h); ++__i) {		\
 +		if (!kh_exist(h,__i)) continue;						\
 +		(kvar) = kh_key(h,__i);								\
 +		(vvar) = kh_val(h,__i);								\
 +		code;												\
 +	} }
 +
 +/*! @function
 +  @abstract     Iterate over the values in the hash table
 +  @param  h     Pointer to the hash table [khash_t(name)*]
 +  @param  vvar  Variable to which value will be assigned
 +  @param  code  Block of code to execute
 + */
 +#define kh_foreach_value(h, vvar, code) { khint_t __i;		\
 +	for (__i = kh_begin(h); __i != kh_end(h); ++__i) {		\
 +		if (!kh_exist(h,__i)) continue;						\
 +		(vvar) = kh_val(h,__i);								\
 +		code;												\
 +	} }
 +
 +/* More convenient interfaces */
 +
 +/*! @function
 +  @abstract     Instantiate a hash set containing integer keys
 +  @param  name  Name of the hash table [symbol]
 + */
 +#define KHASH_SET_INIT_INT(name)										\
 +	KHASH_INIT(name, khint32_t, char, 0, kh_int_hash_func, kh_int_hash_equal)
 +
 +/*! @function
 +  @abstract     Instantiate a hash map containing integer keys
 +  @param  name  Name of the hash table [symbol]
 +  @param  khval_t  Type of values [type]
 + */
 +#define KHASH_MAP_INIT_INT(name, khval_t)								\
 +	KHASH_INIT(name, khint32_t, khval_t, 1, kh_int_hash_func, kh_int_hash_equal)
 +
 +/*! @function
 +  @abstract     Instantiate a hash set containing 64-bit integer keys
 +  @param  name  Name of the hash table [symbol]
 + */
 +#define KHASH_SET_INIT_INT64(name)										\
 +	KHASH_INIT(name, khint64_t, char, 0, kh_int64_hash_func, kh_int64_hash_equal)
 +
 +/*! @function
 +  @abstract     Instantiate a hash map containing 64-bit integer keys
 +  @param  name  Name of the hash table [symbol]
 +  @param  khval_t  Type of values [type]
 + */
 +#define KHASH_MAP_INIT_INT64(name, khval_t)								\
 +	KHASH_INIT(name, khint64_t, khval_t, 1, kh_int64_hash_func, kh_int64_hash_equal)
 +
 +typedef const char *kh_cstr_t;
 +/*! @function
 +  @abstract     Instantiate a hash map containing const char* keys
 +  @param  name  Name of the hash table [symbol]
 + */
 +#define KHASH_SET_INIT_STR(name)										\
 +	KHASH_INIT(name, kh_cstr_t, char, 0, kh_str_hash_func, kh_str_hash_equal)
 +
 +/*! @function
 +  @abstract     Instantiate a hash map containing const char* keys
 +  @param  name  Name of the hash table [symbol]
 +  @param  khval_t  Type of values [type]
 + */
 +#define KHASH_MAP_INIT_STR(name, khval_t)								\
 +	KHASH_INIT(name, kh_cstr_t, khval_t, 1, kh_str_hash_func, kh_str_hash_equal)
 +
 +#endif /* __AC_KHASH_H */
 diff --git a/kvec.h b/kvec.h
 new file mode 100644
 index 0000000..10f1c5b
 --- /dev/null
 +++ b/kvec.h
 @@ -0,0 +1,90 @@
 +/* The MIT License
 +
 +   Copyright (c) 2008, by Attractive Chaos <attractor@live.co.uk>
 +
 +   Permission is hereby granted, free of charge, to any person obtaining
 +   a copy of this software and associated documentation files (the
 +   "Software"), to deal in the Software without restriction, including
 +   without limitation the rights to use, copy, modify, merge, publish,
 +   distribute, sublicense, and/or sell copies of the Software, and to
 +   permit persons to whom the Software is furnished to do so, subject to
 +   the following conditions:
 +
 +   The above copyright notice and this permission notice shall be
 +   included in all copies or substantial portions of the Software.
 +
 +   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 +   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 +   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 +   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 +   BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 +   ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 +   CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 +   SOFTWARE.
 +*/
 +
 +/*
 +  An example:
 +
 +#include "kvec.h"
 +int main() {
 +	kvec_t(int) array;
 +	kv_init(array);
 +	kv_push(int, array, 10); // append
 +	kv_a(int, array, 20) = 5; // dynamic
 +	kv_A(array, 20) = 4; // static
 +	kv_destroy(array);
 +	return 0;
 +}
 +*/
 +
 +/*
 +  2008-09-22 (0.1.0):
 +
 +	* The initial version.
 +
 +*/
 +
 +#ifndef AC_KVEC_H
 +#define AC_KVEC_H
 +
 +#include <stdlib.h>
 +
 +#define kv_roundup32(x) (--(x), (x)|=(x)>>1, (x)|=(x)>>2, (x)|=(x)>>4, (x)|=(x)>>8, (x)|=(x)>>16, ++(x))
 +
 +#define kvec_t(type) struct { size_t n, m; type *a; }
 +#define kv_init(v) ((v).n = (v).m = 0, (v).a = 0)
 +#define kv_destroy(v) free((v).a)
 +#define kv_A(v, i) ((v).a[(i)])
 +#define kv_pop(v) ((v).a[--(v).n])
 +#define kv_size(v) ((v).n)
 +#define kv_max(v) ((v).m)
 +
 +#define kv_resize(type, v, s)  ((v).m = (s), (v).a = (type*)realloc((v).a, sizeof(type) * (v).m))
 +
 +#define kv_copy(type, v1, v0) do {							\
 +		if ((v1).m < (v0).n) kv_resize(type, v1, (v0).n);	\
 +		(v1).n = (v0).n;									\
 +		memcpy((v1).a, (v0).a, sizeof(type) * (v0).n);		\
 +	} while (0)												\
 +
 +#define kv_push(type, v, x) do {									\
 +		if ((v).n == (v).m) {										\
 +			(v).m = (v).m? (v).m<<1 : 2;							\
 +			(v).a = (type*)realloc((v).a, sizeof(type) * (v).m);	\
 +		}															\
 +		(v).a[(v).n++] = (x);										\
 +	} while (0)
 +
 +#define kv_pushp(type, v) ((((v).n == (v).m)?							\
 +						   ((v).m = ((v).m? (v).m<<1 : 2),				\
 +							(v).a = (type*)realloc((v).a, sizeof(type) * (v).m), 0)	\
 +						   : 0), ((v).a + ((v).n++)))
 +
 +#define kv_a(type, v, i) (((v).m <= (size_t)(i)? \
 +						  ((v).m = (v).n = (i) + 1, kv_roundup32((v).m), \
 +						   (v).a = (type*)realloc((v).a, sizeof(type) * (v).m), 0) \
 +						  : (v).n <= (size_t)(i)? (v).n = (i) + 1 \
 +						  : 0), (v).a[(i)])
 +
 +#endif
 diff --git a/rowcolumn_diacritics_helpers.c b/rowcolumn_diacritics_helpers.c
 new file mode 100644
 index 0000000..829c0fc
 --- /dev/null
 +++ b/rowcolumn_diacritics_helpers.c
 @@ -0,0 +1,391 @@
 +#include <stdint.h>
 +
 +uint16_t diacritic_to_num(uint32_t code)
 +{
 +	switch (code) {
 +	case 0x305:
 +		return code - 0x305 + 1;
 +	case 0x30d:
 +	case 0x30e:
 +		return code - 0x30d + 2;
 +	case 0x310:
 +		return code - 0x310 + 4;
 +	case 0x312:
 +		return code - 0x312 + 5;
 +	case 0x33d:
 +	case 0x33e:
 +	case 0x33f:
 +		return code - 0x33d + 6;
 +	case 0x346:
 +		return code - 0x346 + 9;
 +	case 0x34a:
 +	case 0x34b:
 +	case 0x34c:
 +		return code - 0x34a + 10;
 +	case 0x350:
 +	case 0x351:
 +	case 0x352:
 +		return code - 0x350 + 13;
 +	case 0x357:
 +		return code - 0x357 + 16;
 +	case 0x35b:
 +		return code - 0x35b + 17;
 +	case 0x363:
 +	case 0x364:
 +	case 0x365:
 +	case 0x366:
 +	case 0x367:
 +	case 0x368:
 +	case 0x369:
 +	case 0x36a:
 +	case 0x36b:
 +	case 0x36c:
 +	case 0x36d:
 +	case 0x36e:
 +	case 0x36f:
 +		return code - 0x363 + 18;
 +	case 0x483:
 +	case 0x484:
 +	case 0x485:
 +	case 0x486:
 +	case 0x487:
 +		return code - 0x483 + 31;
 +	case 0x592:
 +	case 0x593:
 +	case 0x594:
 +	case 0x595:
 +		return code - 0x592 + 36;
 +	case 0x597:
 +	case 0x598:
 +	case 0x599:
 +		return code - 0x597 + 40;
 +	case 0x59c:
 +	case 0x59d:
 +	case 0x59e:
 +	case 0x59f:
 +	case 0x5a0:
 +	case 0x5a1:
 +		return code - 0x59c + 43;
 +	case 0x5a8:
 +	case 0x5a9:
 +		return code - 0x5a8 + 49;
 +	case 0x5ab:
 +	case 0x5ac:
 +		return code - 0x5ab + 51;
 +	case 0x5af:
 +		return code - 0x5af + 53;
 +	case 0x5c4:
 +		return code - 0x5c4 + 54;
 +	case 0x610:
 +	case 0x611:
 +	case 0x612:
 +	case 0x613:
 +	case 0x614:
 +	case 0x615:
 +	case 0x616:
 +	case 0x617:
 +		return code - 0x610 + 55;
 +	case 0x657:
 +	case 0x658:
 +	case 0x659:
 +	case 0x65a:
 +	case 0x65b:
 +		return code - 0x657 + 63;
 +	case 0x65d:
 +	case 0x65e:
 +		return code - 0x65d + 68;
 +	case 0x6d6:
 +	case 0x6d7:
 +	case 0x6d8:
 +	case 0x6d9:
 +	case 0x6da:
 +	case 0x6db:
 +	case 0x6dc:
 +		return code - 0x6d6 + 70;
 +	case 0x6df:
 +	case 0x6e0:
 +	case 0x6e1:
 +	case 0x6e2:
 +		return code - 0x6df + 77;
 +	case 0x6e4:
 +		return code - 0x6e4 + 81;
 +	case 0x6e7:
 +	case 0x6e8:
 +		return code - 0x6e7 + 82;
 +	case 0x6eb:
 +	case 0x6ec:
 +		return code - 0x6eb + 84;
 +	case 0x730:
 +		return code - 0x730 + 86;
 +	case 0x732:
 +	case 0x733:
 +		return code - 0x732 + 87;
 +	case 0x735:
 +	case 0x736:
 +		return code - 0x735 + 89;
 +	case 0x73a:
 +		return code - 0x73a + 91;
 +	case 0x73d:
 +		return code - 0x73d + 92;
 +	case 0x73f:
 +	case 0x740:
 +	case 0x741:
 +		return code - 0x73f + 93;
 +	case 0x743:
 +		return code - 0x743 + 96;
 +	case 0x745:
 +		return code - 0x745 + 97;
 +	case 0x747:
 +		return code - 0x747 + 98;
 +	case 0x749:
 +	case 0x74a:
 +		return code - 0x749 + 99;
 +	case 0x7eb:
 +	case 0x7ec:
 +	case 0x7ed:
 +	case 0x7ee:
 +	case 0x7ef:
 +	case 0x7f0:
 +	case 0x7f1:
 +		return code - 0x7eb + 101;
 +	case 0x7f3:
 +		return code - 0x7f3 + 108;
 +	case 0x816:
 +	case 0x817:
 +	case 0x818:
 +	case 0x819:
 +		return code - 0x816 + 109;
 +	case 0x81b:
 +	case 0x81c:
 +	case 0x81d:
 +	case 0x81e:
 +	case 0x81f:
 +	case 0x820:
 +	case 0x821:
 +	case 0x822:
 +	case 0x823:
 +		return code - 0x81b + 113;
 +	case 0x825:
 +	case 0x826:
 +	case 0x827:
 +		return code - 0x825 + 122;
 +	case 0x829:
 +	case 0x82a:
 +	case 0x82b:
 +	case 0x82c:
 +	case 0x82d:
 +		return code - 0x829 + 125;
 +	case 0x951:
 +		return code - 0x951 + 130;
 +	case 0x953:
 +	case 0x954:
 +		return code - 0x953 + 131;
 +	case 0xf82:
 +	case 0xf83:
 +		return code - 0xf82 + 133;
 +	case 0xf86:
 +	case 0xf87:
 +		return code - 0xf86 + 135;
 +	case 0x135d:
 +	case 0x135e:
 +	case 0x135f:
 +		return code - 0x135d + 137;
 +	case 0x17dd:
 +		return code - 0x17dd + 140;
 +	case 0x193a:
 +		return code - 0x193a + 141;
 +	case 0x1a17:
 +		return code - 0x1a17 + 142;
 +	case 0x1a75:
 +	case 0x1a76:
 +	case 0x1a77:
 +	case 0x1a78:
 +	case 0x1a79:
 +	case 0x1a7a:
 +	case 0x1a7b:
 +	case 0x1a7c:
 +		return code - 0x1a75 + 143;
 +	case 0x1b6b:
 +		return code - 0x1b6b + 151;
 +	case 0x1b6d:
 +	case 0x1b6e:
 +	case 0x1b6f:
 +	case 0x1b70:
 +	case 0x1b71:
 +	case 0x1b72:
 +	case 0x1b73:
 +		return code - 0x1b6d + 152;
 +	case 0x1cd0:
 +	case 0x1cd1:
 +	case 0x1cd2:
 +		return code - 0x1cd0 + 159;
 +	case 0x1cda:
 +	case 0x1cdb:
 +		return code - 0x1cda + 162;
 +	case 0x1ce0:
 +		return code - 0x1ce0 + 164;
 +	case 0x1dc0:
 +	case 0x1dc1:
 +		return code - 0x1dc0 + 165;
 +	case 0x1dc3:
 +	case 0x1dc4:
 +	case 0x1dc5:
 +	case 0x1dc6:
 +	case 0x1dc7:
 +	case 0x1dc8:
 +	case 0x1dc9:
 +		return code - 0x1dc3 + 167;
 +	case 0x1dcb:
 +	case 0x1dcc:
 +		return code - 0x1dcb + 174;
 +	case 0x1dd1:
 +	case 0x1dd2:
 +	case 0x1dd3:
 +	case 0x1dd4:
 +	case 0x1dd5:
 +	case 0x1dd6:
 +	case 0x1dd7:
 +	case 0x1dd8:
 +	case 0x1dd9:
 +	case 0x1dda:
 +	case 0x1ddb:
 +	case 0x1ddc:
 +	case 0x1ddd:
 +	case 0x1dde:
 +	case 0x1ddf:
 +	case 0x1de0:
 +	case 0x1de1:
 +	case 0x1de2:
 +	case 0x1de3:
 +	case 0x1de4:
 +	case 0x1de5:
 +	case 0x1de6:
 +		return code - 0x1dd1 + 176;
 +	case 0x1dfe:
 +		return code - 0x1dfe + 198;
 +	case 0x20d0:
 +	case 0x20d1:
 +		return code - 0x20d0 + 199;
 +	case 0x20d4:
 +	case 0x20d5:
 +	case 0x20d6:
 +	case 0x20d7:
 +		return code - 0x20d4 + 201;
 +	case 0x20db:
 +	case 0x20dc:
 +		return code - 0x20db + 205;
 +	case 0x20e1:
 +		return code - 0x20e1 + 207;
 +	case 0x20e7:
 +		return code - 0x20e7 + 208;
 +	case 0x20e9:
 +		return code - 0x20e9 + 209;
 +	case 0x20f0:
 +		return code - 0x20f0 + 210;
 +	case 0x2cef:
 +	case 0x2cf0:
 +	case 0x2cf1:
 +		return code - 0x2cef + 211;
 +	case 0x2de0:
 +	case 0x2de1:
 +	case 0x2de2:
 +	case 0x2de3:
 +	case 0x2de4:
 +	case 0x2de5:
 +	case 0x2de6:
 +	case 0x2de7:
 +	case 0x2de8:
 +	case 0x2de9:
 +	case 0x2dea:
 +	case 0x2deb:
 +	case 0x2dec:
 +	case 0x2ded:
 +	case 0x2dee:
 +	case 0x2def:
 +	case 0x2df0:
 +	case 0x2df1:
 +	case 0x2df2:
 +	case 0x2df3:
 +	case 0x2df4:
 +	case 0x2df5:
 +	case 0x2df6:
 +	case 0x2df7:
 +	case 0x2df8:
 +	case 0x2df9:
 +	case 0x2dfa:
 +	case 0x2dfb:
 +	case 0x2dfc:
 +	case 0x2dfd:
 +	case 0x2dfe:
 +	case 0x2dff:
 +		return code - 0x2de0 + 214;
 +	case 0xa66f:
 +		return code - 0xa66f + 246;
 +	case 0xa67c:
 +	case 0xa67d:
 +		return code - 0xa67c + 247;
 +	case 0xa6f0:
 +	case 0xa6f1:
 +		return code - 0xa6f0 + 249;
 +	case 0xa8e0:
 +	case 0xa8e1:
 +	case 0xa8e2:
 +	case 0xa8e3:
 +	case 0xa8e4:
 +	case 0xa8e5:
 +	case 0xa8e6:
 +	case 0xa8e7:
 +	case 0xa8e8:
 +	case 0xa8e9:
 +	case 0xa8ea:
 +	case 0xa8eb:
 +	case 0xa8ec:
 +	case 0xa8ed:
 +	case 0xa8ee:
 +	case 0xa8ef:
 +	case 0xa8f0:
 +	case 0xa8f1:
 +		return code - 0xa8e0 + 251;
 +	case 0xaab0:
 +		return code - 0xaab0 + 269;
 +	case 0xaab2:
 +	case 0xaab3:
 +		return code - 0xaab2 + 270;
 +	case 0xaab7:
 +	case 0xaab8:
 +		return code - 0xaab7 + 272;
 +	case 0xaabe:
 +	case 0xaabf:
 +		return code - 0xaabe + 274;
 +	case 0xaac1:
 +		return code - 0xaac1 + 276;
 +	case 0xfe20:
 +	case 0xfe21:
 +	case 0xfe22:
 +	case 0xfe23:
 +	case 0xfe24:
 +	case 0xfe25:
 +	case 0xfe26:
 +		return code - 0xfe20 + 277;
 +	case 0x10a0f:
 +		return code - 0x10a0f + 284;
 +	case 0x10a38:
 +		return code - 0x10a38 + 285;
 +	case 0x1d185:
 +	case 0x1d186:
 +	case 0x1d187:
 +	case 0x1d188:
 +	case 0x1d189:
 +		return code - 0x1d185 + 286;
 +	case 0x1d1aa:
 +	case 0x1d1ab:
 +	case 0x1d1ac:
 +	case 0x1d1ad:
 +		return code - 0x1d1aa + 291;
 +	case 0x1d242:
 +	case 0x1d243:
 +	case 0x1d244:
 +		return code - 0x1d242 + 295;
 +	}
 +	return 0;
 +}
 diff --git a/st.c b/st.c
 index 8e57991..9824ea6 100644
 --- a/st.c
 +++ b/st.c
 @@ -19,6 +19,7 @@
  
  #include "st.h"
  #include "win.h"
 +#include "graphics.h"
  
  #if   defined(__linux)
   #include <pty.h>
 @@ -36,6 +37,10 @@
  #define STR_BUF_SIZ   ESC_BUF_SIZ
  #define STR_ARG_SIZ   ESC_ARG_SIZ
  
 +/* PUA character used as an image placeholder */
 +#define IMAGE_PLACEHOLDER_CHAR 0x10EEEE
 +#define IMAGE_PLACEHOLDER_CHAR_OLD 0xEEEE
 +
  /* macros */
  #define IS_SET(flag)		((term.mode & (flag)) != 0)
  #define ISCONTROLC0(c)		(BETWEEN(c, 0, 0x1f) || (c) == 0x7f)
 @@ -113,6 +118,8 @@ typedef struct {
  typedef struct {
  	int row;      /* nb row */
  	int col;      /* nb col */
 +	int pixw;     /* width of the text area in pixels */
 +	int pixh;     /* height of the text area in pixels */
  	Line *line;   /* screen */
  	Line *alt;    /* alternate screen */
  	int *dirty;   /* dirtyness of lines */
 @@ -213,7 +220,6 @@ static Rune utf8decodebyte(char, size_t *);
  static char utf8encodebyte(Rune, size_t);
  static size_t utf8validate(Rune *, size_t);
  
 -static char *base64dec(const char *);
  static char base64dec_getc(const char **);
  
  static ssize_t xwrite(int, const char *, size_t);
 @@ -232,6 +238,10 @@ static const uchar utfmask[UTF_SIZ + 1] = {0xC0, 0x80, 0xE0, 0xF0, 0xF8};
  static const Rune utfmin[UTF_SIZ + 1] = {       0,    0,  0x80,  0x800,  0x10000};
  static const Rune utfmax[UTF_SIZ + 1] = {0x10FFFF, 0x7F, 0x7FF, 0xFFFF, 0x10FFFF};
  
 +/* Converts a diacritic to a row/column/etc number. The result is 1-base, 0
 + * means "couldn't convert". Defined in rowcolumn_diacritics_helpers.c */
 +uint16_t diacritic_to_num(uint32_t code);
 +
  ssize_t
  xwrite(int fd, const char *s, size_t len)
  {
 @@ -616,6 +626,12 @@ getsel(void)
  			if (gp->mode & ATTR_WDUMMY)
  				continue;
  
 +			if (gp->mode & ATTR_IMAGE) {
 +				// TODO: Copy diacritics as well
 +				ptr += utf8encode(IMAGE_PLACEHOLDER_CHAR, ptr);
 +				continue;
 +			}
 +
  			ptr += utf8encode(gp->u, ptr);
  		}
  
 @@ -715,11 +731,14 @@ sigchld(int a)
  	int stat;
  	pid_t p;
  
 -	if ((p = waitpid(pid, &stat, WNOHANG)) < 0)
 +	if ((p = waitpid(-1, &stat, WNOHANG)) < 0)
  		die("waiting for pid %hd failed: %s\n", pid, strerror(errno));
  
 -	if (pid != p)
 +	if (pid != p) {
 +		/* reinstall sigchld handler */
 +		signal(SIGCHLD, sigchld);
  		return;
 +	}
  
  	if (WIFEXITED(stat) && WEXITSTATUS(stat))
  		die("child exited with status %d\n", WEXITSTATUS(stat));
 @@ -819,7 +838,11 @@ ttyread(void)
  {
  	static char buf[BUFSIZ];
  	static int buflen = 0;
 -	int ret, written;
 +	static int already_processing = 0;
 +	int ret, written = 0;
 +
 +	if (buflen >= LEN(buf))
 +		return 0;
  
  	/* append read bytes to unprocessed bytes */
  	ret = read(cmdfd, buf+buflen, LEN(buf)-buflen);
 @@ -831,7 +854,24 @@ ttyread(void)
  		die("couldn't read from shell: %s\n", strerror(errno));
  	default:
  		buflen += ret;
 -		written = twrite(buf, buflen, 0);
 +		if (already_processing) {
 +			/* Avoid recursive call to twrite() */
 +			return ret;
 +		}
 +		already_processing = 1;
 +		while (1) {
 +			int buflen_before_processing = buflen;
 +			written += twrite(buf + written, buflen - written, 0);
 +			// If buflen changed during the call to twrite, there is
 +			// new data, and we need to keep processing, otherwise
 +			// we can exit. This will not loop forever because the
 +			// buffer is limited, and we don't clean it in this
 +			// loop, so at some point ttywrite will have to drop
 +			// some data.
 +			if (buflen_before_processing == buflen)
 +				break;
 +		}
 +		already_processing = 0;
  		buflen -= written;
  		/* keep any incomplete UTF-8 byte sequence for the next call */
  		if (buflen > 0)
 @@ -874,6 +914,7 @@ ttywriteraw(const char *s, size_t n)
  	fd_set wfd, rfd;
  	ssize_t r;
  	size_t lim = 256;
 +	int retries_left = 100;
  
  	/*
  	 * Remember that we are using a pty, which might be a modem line.
 @@ -882,6 +923,9 @@ ttywriteraw(const char *s, size_t n)
  	 * FIXME: Migrate the world to Plan 9.
  	 */
  	while (n > 0) {
 +		if (retries_left-- <= 0)
 +			goto too_many_retries;
 +
  		FD_ZERO(&wfd);
  		FD_ZERO(&rfd);
  		FD_SET(cmdfd, &wfd);
 @@ -923,11 +967,16 @@ ttywriteraw(const char *s, size_t n)
  
  write_error:
  	die("write error on tty: %s\n", strerror(errno));
 +too_many_retries:
 +	fprintf(stderr, "Could not write %zu bytes to tty\n", n);
  }
  
  void
  ttyresize(int tw, int th)
  {
 +	term.pixw = tw;
 +	term.pixh = th;
 +
  	struct winsize w;
  
  	w.ws_row = term.row;
 @@ -1015,7 +1064,8 @@ treset(void)
  	term.c = (TCursor){{
  		.mode = ATTR_NULL,
  		.fg = defaultfg,
 -		.bg = defaultbg
 +		.bg = defaultbg,
 +		.decor = DECOR_DEFAULT_COLOR
  	}, .x = 0, .y = 0, .state = CURSOR_DEFAULT};
  
  	memset(term.tabs, 0, term.col * sizeof(*term.tabs));
 @@ -1038,7 +1088,9 @@ treset(void)
  void
  tnew(int col, int row)
  {
 -	term = (Term){ .c = { .attr = { .fg = defaultfg, .bg = defaultbg } } };
 +	term = (Term){.c = {.attr = {.fg = defaultfg,
 +				     .bg = defaultbg,
 +				     .decor = DECOR_DEFAULT_COLOR}}};
  	tresize(col, row);
  	treset();
  }
 @@ -1215,9 +1267,24 @@ tsetchar(Rune u, const Glyph *attr, int x, int y)
  		term.line[y][x-1].mode &= ~ATTR_WIDE;
  	}
  
 +	if (u == ' ' && term.line[y][x].mode & ATTR_IMAGE &&
 +	    tgetisclassicplaceholder(&term.line[y][x])) {
 +		// This is a workaround: don't overwrite classic placement
 +		// placeholders with space symbols (unlike Unicode placeholders
 +		// which must be overwritten by anything).
 +		term.line[y][x].bg = attr->bg;
 +		term.dirty[y] = 1;
 +		return;
 +	}
 +
  	term.dirty[y] = 1;
  	term.line[y][x] = *attr;
  	term.line[y][x].u = u;
 +
 +	if (u == IMAGE_PLACEHOLDER_CHAR || u == IMAGE_PLACEHOLDER_CHAR_OLD) {
 +		term.line[y][x].u = 0;
 +		term.line[y][x].mode |= ATTR_IMAGE;
 +	}
  }
  
  void
 @@ -1244,12 +1311,110 @@ tclearregion(int x1, int y1, int x2, int y2)
  				selclear();
  			gp->fg = term.c.attr.fg;
  			gp->bg = term.c.attr.bg;
 +			gp->decor = term.c.attr.decor;
  			gp->mode = 0;
  			gp->u = ' ';
  		}
  	}
  }
  
 +/// Fills a rectangle area with an image placeholder. The starting point is the
 +/// cursor. Adds empty lines if needed. The placeholder will be marked as
 +/// classic.
 +void tcreateimgplaceholder(uint32_t image_id, uint32_t placement_id, int cols,
 +			   int rows, char do_not_move_cursor,
 +			   Glyph *text_underneath) {
 +	for (int row = 0; row < rows; ++row) {
 +		int y = term.c.y;
 +		term.dirty[y] = 1;
 +		for (int col = 0; col < cols; ++col) {
 +			int x = term.c.x + col;
 +			if (x >= term.col)
 +				break;
 +			Glyph *gp = &term.line[y][x];
 +			if (selected(x, y))
 +				selclear();
 +			if (text_underneath) {
 +				Glyph *to_save = gp;
 +				// If there is already a classic placeholder,
 +				// use the text underneath it. This will leave
 +				// holes in images, but at least we are
 +				// guaranteed to restore the original text.
 +				if (gp->mode & ATTR_IMAGE &&
 +				    tgetisclassicplaceholder(gp)) {
 +					Glyph *under =
 +						gr_get_glyph_underneath_image(
 +							tgetimgid(gp),
 +							tgetimgplacementid(gp),
 +							tgetimgcol(gp),
 +							tgetimgrow(gp));
 +					if (under)
 +						to_save = under;
 +				}
 +				text_underneath[cols * row + col] = *to_save;
 +			}
 +			gp->mode = ATTR_IMAGE;
 +			gp->u = 0;
 +			tsetimgrow(gp, row + 1);
 +			tsetimgcol(gp, col + 1);
 +			tsetimgid(gp, image_id);
 +			tsetimgplacementid(gp, placement_id);
 +			tsetimgdiacriticcount(gp, 3);
 +			tsetisclassicplaceholder(gp, 1);
 +		}
 +		// If moving the cursor is not allowed and this is the last line
 +		// of the terminal, we are done.
 +		if (do_not_move_cursor && y == term.row - 1)
 +			break;
 +		// Move the cursor down, maybe creating a new line. The x is
 +		// preserved (we never change term.c.x in the loop above).
 +		if (row != rows - 1)
 +			tnewline(/*first_col=*/0);
 +	}
 +	if (do_not_move_cursor) {
 +		// Return the cursor to the original position.
 +		tmoveto(term.c.x, term.c.y - rows + 1);
 +	} else {
 +		// Move the cursor beyond the last column, as required by the
 +		// protocol. If the cursor goes beyond the screen edge, insert a
 +		// newline to match the behavior of kitty.
 +		if (term.c.x + cols >= term.col)
 +			tnewline(/*first_col=*/1);
 +		else
 +			tmoveto(term.c.x + cols, term.c.y);
 +	}
 +}
 +
 +void gr_for_each_image_cell(int (*callback)(void *data, Glyph *gp),
 +			    void *data) {
 +	for (int row = 0; row < term.row; ++row) {
 +		for (int col = 0; col < term.col; ++col) {
 +			Glyph *gp = &term.line[row][col];
 +			if (gp->mode & ATTR_IMAGE) {
 +				if (callback(data, gp))
 +					term.dirty[row] = 1;
 +			}
 +		}
 +	}
 +}
 +
 +void gr_schedule_image_redraw_by_id(uint32_t image_id) {
 +	for (int row = 0; row < term.row; ++row) {
 +		if (term.dirty[row])
 +			continue;
 +		for (int col = 0; col < term.col; ++col) {
 +			Glyph *gp = &term.line[row][col];
 +			if (gp->mode & ATTR_IMAGE) {
 +				uint32_t cell_image_id = tgetimgid(gp);
 +				if (cell_image_id == image_id) {
 +					term.dirty[row] = 1;
 +					break;
 +				}
 +			}
 +		}
 +	}
 +}
 +
  void
  tdeletechar(int n)
  {
 @@ -1368,6 +1533,7 @@ tsetattr(const int *attr, int l)
  				ATTR_STRUCK     );
  			term.c.attr.fg = defaultfg;
  			term.c.attr.bg = defaultbg;
 +			term.c.attr.decor = DECOR_DEFAULT_COLOR;
  			break;
  		case 1:
  			term.c.attr.mode |= ATTR_BOLD;
 @@ -1380,6 +1546,20 @@ tsetattr(const int *attr, int l)
  			break;
  		case 4:
  			term.c.attr.mode |= ATTR_UNDERLINE;
 +			if (i + 1 < l) {
 +				idx = attr[++i];
 +				if (BETWEEN(idx, 1, 5)) {
 +					tsetdecorstyle(&term.c.attr, idx);
 +				} else if (idx == 0) {
 +					term.c.attr.mode &= ~ATTR_UNDERLINE;
 +					tsetdecorstyle(&term.c.attr, 0);
 +				} else {
 +					fprintf(stderr,
 +						"erresc: unknown underline "
 +						"style %d\n",
 +						idx);
 +				}
 +			}
  			break;
  		case 5: /* slow blink */
  			/* FALLTHROUGH */
 @@ -1403,6 +1583,7 @@ tsetattr(const int *attr, int l)
  			break;
  		case 24:
  			term.c.attr.mode &= ~ATTR_UNDERLINE;
 +			tsetdecorstyle(&term.c.attr, 0);
  			break;
  		case 25:
  			term.c.attr.mode &= ~ATTR_BLINK;
 @@ -1431,10 +1612,11 @@ tsetattr(const int *attr, int l)
  			term.c.attr.bg = defaultbg;
  			break;
  		case 58:
 -			/* This starts a sequence to change the color of
 -			 * "underline" pixels. We don't support that and
 -			 * instead eat up a following "5;n" or "2;r;g;b". */
 -			tdefcolor(attr, &i, l);
 +			if ((idx = tdefcolor(attr, &i, l)) >= 0)
 +				tsetdecorcolor(&term.c.attr, idx);
 +			break;
 +		case 59:
 +			tsetdecorcolor(&term.c.attr, DECOR_DEFAULT_COLOR);
  			break;
  		default:
  			if (BETWEEN(attr[i], 30, 37)) {
 @@ -1823,6 +2005,39 @@ csihandle(void)
  			goto unknown;
  		}
  		break;
 +	case '>':
 +		switch (csiescseq.mode[1]) {
 +		case 'q': /* XTVERSION -- Print terminal name and version */
 +			len = snprintf(buf, sizeof(buf),
 +				       "\033P>|st-graphics(%s)\033\\", VERSION);
 +			ttywrite(buf, len, 0);
 +			break;
 +		default:
 +			goto unknown;
 +		}
 +		break;
 +	case 't': /* XTWINOPS -- Window manipulation */
 +		switch (csiescseq.arg[0]) {
 +		case 14: /* Report text area size in pixels. */
 +			len = snprintf(buf, sizeof(buf), "\033[4;%i;%it",
 +					term.pixh, term.pixw);
 +			ttywrite(buf, len, 0);
 +			break;
 +		case 16: /* Report character cell size in pixels. */
 +			len = snprintf(buf, sizeof(buf), "\033[6;%i;%it",
 +					term.pixh / term.row,
 +					term.pixw / term.col);
 +			ttywrite(buf, len, 0);
 +			break;
 +		case 18: /* Report the size of the text area in characters. */
 +			len = snprintf(buf, sizeof(buf), "\033[8;%i;%it",
 +					term.row, term.col);
 +			ttywrite(buf, len, 0);
 +			break;
 +		default:
 +			goto unknown;
 +		}
 +		break;
  	}
  }
  
 @@ -1985,8 +2200,27 @@ strhandle(void)
  	case 'k': /* old title set compatibility */
  		xsettitle(strescseq.args[0]);
  		return;
 -	case 'P': /* DCS -- Device Control String */
  	case '_': /* APC -- Application Program Command */
 +		if (gr_parse_command(strescseq.buf, strescseq.len)) {
 +			GraphicsCommandResult *res = &graphics_command_result;
 +			if (res->create_placeholder) {
 +				tcreateimgplaceholder(
 +					res->placeholder.image_id,
 +					res->placeholder.placement_id,
 +					res->placeholder.columns,
 +					res->placeholder.rows,
 +					res->placeholder.do_not_move_cursor,
 +					res->placeholder.text_underneath);
 +			}
 +			if (res->response[0])
 +				ttywrite(res->response, strlen(res->response),
 +					 0);
 +			if (res->redraw)
 +				tfulldirt();
 +			return;
 +		}
 +		return;
 +	case 'P': /* DCS -- Device Control String */
  	case '^': /* PM -- Privacy Message */
  		return;
  	}
 @@ -2492,6 +2726,41 @@ check_control_code:
  	if (selected(term.c.x, term.c.y))
  		selclear();
  
 +	// wcwidth is broken on some systems, set the width to 0 if it's a known
 +	// diacritic used for images.
 +	uint16_t num = diacritic_to_num(u);
 +	if (num != 0)
 +		width = 0;
 +	// Set the width to 1 if it's an image placeholder character.
 +	if (u == IMAGE_PLACEHOLDER_CHAR || u == IMAGE_PLACEHOLDER_CHAR_OLD)
 +		width = 1;
 +
 +	if (width == 0) {
 +		// It's probably a combining char. Combining characters are not
 +		// supported, so we just ignore them, unless it denotes the row and
 +		// column of an image character.
 +		if (term.c.y <= 0 && term.c.x <= 0)
 +			return;
 +		else if (term.c.x == 0)
 +			gp = &term.line[term.c.y-1][term.col-1];
 +		else if (term.c.state & CURSOR_WRAPNEXT)
 +			gp = &term.line[term.c.y][term.c.x];
 +		else
 +			gp = &term.line[term.c.y][term.c.x-1];
 +		if (num && (gp->mode & ATTR_IMAGE)) {
 +			unsigned diaccount = tgetimgdiacriticcount(gp);
 +			if (diaccount == 0)
 +				tsetimgrow(gp, num);
 +			else if (diaccount == 1)
 +				tsetimgcol(gp, num);
 +			else if (diaccount == 2)
 +				tsetimg4thbyteplus1(gp, num);
 +			tsetimgdiacriticcount(gp, diaccount + 1);
 +		}
 +		term.lastc = u;
 +		return;
 +	}
 +
  	gp = &term.line[term.c.y][term.c.x];
  	if (IS_SET(MODE_WRAP) && (term.c.state & CURSOR_WRAPNEXT)) {
  		gp->mode |= ATTR_WRAP;
 @@ -2658,6 +2927,8 @@ drawregion(int x1, int y1, int x2, int y2)
  {
  	int y;
  
 +	xstartimagedraw(term.dirty, term.row);
 +
  	for (y = y1; y < y2; y++) {
  		if (!term.dirty[y])
  			continue;
 @@ -2665,6 +2936,8 @@ drawregion(int x1, int y1, int x2, int y2)
  		term.dirty[y] = 0;
  		xdrawline(term.line[y], x1, y, x2);
  	}
 +
 +	xfinishimagedraw();
  }
  
  void
 @@ -2699,3 +2972,9 @@ redraw(void)
  	tfulldirt();
  	draw();
  }
 +
 +Glyph
 +getglyphat(int col, int row)
 +{
 +	return term.line[row][col];
 +}
 diff --git a/st.h b/st.h
 index fd3b0d8..c5dd731 100644
 --- a/st.h
 +++ b/st.h
 @@ -12,7 +12,7 @@
  #define DEFAULT(a, b)		(a) = (a) ? (a) : (b)
  #define LIMIT(x, a, b)		(x) = (x) < (a) ? (a) : (x) > (b) ? (b) : (x)
  #define ATTRCMP(a, b)		((a).mode != (b).mode || (a).fg != (b).fg || \
 -				(a).bg != (b).bg)
 +				(a).bg != (b).bg || (a).decor != (b).decor)
  #define TIMEDIFF(t1, t2)	((t1.tv_sec-t2.tv_sec)*1000 + \
  				(t1.tv_nsec-t2.tv_nsec)/1E6)
  #define MODBIT(x, set, bit)	((set) ? ((x) |= (bit)) : ((x) &= ~(bit)))
 @@ -20,6 +20,10 @@
  #define TRUECOLOR(r,g,b)	(1 << 24 | (r) << 16 | (g) << 8 | (b))
  #define IS_TRUECOL(x)		(1 << 24 & (x))
  
 +// This decor color indicates that the fg color should be used. Note that it's
 +// not a 24-bit color because the 25-th bit is not set.
 +#define DECOR_DEFAULT_COLOR	0x0ffffff
 +
  enum glyph_attribute {
  	ATTR_NULL       = 0,
  	ATTR_BOLD       = 1 << 0,
 @@ -34,6 +38,7 @@ enum glyph_attribute {
  	ATTR_WIDE       = 1 << 9,
  	ATTR_WDUMMY     = 1 << 10,
  	ATTR_BOLD_FAINT = ATTR_BOLD | ATTR_FAINT,
 +	ATTR_IMAGE      = 1 << 14,
  };
  
  enum selection_mode {
 @@ -52,6 +57,14 @@ enum selection_snap {
  	SNAP_LINE = 2
  };
  
 +enum underline_style {
 +	UNDERLINE_STRAIGHT = 1,
 +	UNDERLINE_DOUBLE = 2,
 +	UNDERLINE_CURLY = 3,
 +	UNDERLINE_DOTTED = 4,
 +	UNDERLINE_DASHED = 5,
 +};
 +
  typedef unsigned char uchar;
  typedef unsigned int uint;
  typedef unsigned long ulong;
 @@ -65,6 +78,7 @@ typedef struct {
  	ushort mode;      /* attribute flags */
  	uint32_t fg;      /* foreground  */
  	uint32_t bg;      /* background  */
 +	uint32_t decor;   /* decoration (like underline) */
  } Glyph;
  
  typedef Glyph *Line;
 @@ -105,6 +119,8 @@ void selextend(int, int, int, int);
  int selected(int, int);
  char *getsel(void);
  
 +Glyph getglyphat(int, int);
 +
  size_t utf8encode(Rune, char *);
  
  void *xmalloc(size_t);
 @@ -124,3 +140,69 @@ extern unsigned int tabspaces;
  extern unsigned int defaultfg;
  extern unsigned int defaultbg;
  extern unsigned int defaultcs;
 +
 +// Accessors to decoration properties stored in `decor`.
 +// The 25-th bit is used to indicate if it's a 24-bit color.
 +static inline uint32_t tgetdecorcolor(Glyph *g) { return g->decor & 0x1ffffff; }
 +static inline uint32_t tgetdecorstyle(Glyph *g) { return (g->decor >> 25) & 0x7; }
 +static inline void tsetdecorcolor(Glyph *g, uint32_t color) {
 +	g->decor = (g->decor & ~0x1ffffff) | (color & 0x1ffffff);
 +}
 +static inline void tsetdecorstyle(Glyph *g, uint32_t style) {
 +	g->decor = (g->decor & ~(0x7 << 25)) | ((style & 0x7) << 25);
 +}
 +
 +
 +// Some accessors to image placeholder properties stored in `u`:
 +// - row (1-base) - 9 bits
 +// - column (1-base) - 9 bits
 +// - most significant byte of the image id plus 1 - 9 bits (0 means unspecified,
 +//   don't forget to subtract 1).
 +// - the original number of diacritics (0, 1, 2, or 3) - 2 bits
 +// - whether this is a classic (1) or Unicode (0) placeholder - 1 bit
 +static inline uint32_t tgetimgrow(Glyph *g) { return g->u & 0x1ff; }
 +static inline uint32_t tgetimgcol(Glyph *g) { return (g->u >> 9) & 0x1ff; }
 +static inline uint32_t tgetimgid4thbyteplus1(Glyph *g) { return (g->u >> 18) & 0x1ff; }
 +static inline uint32_t tgetimgdiacriticcount(Glyph *g) { return (g->u >> 27) & 0x3; }
 +static inline uint32_t tgetisclassicplaceholder(Glyph *g) { return (g->u >> 29) & 0x1; }
 +static inline void tsetimgrow(Glyph *g, uint32_t row) {
 +	g->u = (g->u & ~0x1ff) | (row & 0x1ff);
 +}
 +static inline void tsetimgcol(Glyph *g, uint32_t col) {
 +	g->u = (g->u & ~(0x1ff << 9)) | ((col & 0x1ff) << 9);
 +}
 +static inline void tsetimg4thbyteplus1(Glyph *g, uint32_t byteplus1) {
 +	g->u = (g->u & ~(0x1ff << 18)) | ((byteplus1 & 0x1ff) << 18);
 +}
 +static inline void tsetimgdiacriticcount(Glyph *g, uint32_t count) {
 +	g->u = (g->u & ~(0x3 << 27)) | ((count & 0x3) << 27);
 +}
 +static inline void tsetisclassicplaceholder(Glyph *g, uint32_t isclassic) {
 +	g->u = (g->u & ~(0x1 << 29)) | ((isclassic & 0x1) << 29);
 +}
 +
 +/// Returns the full image id. This is a naive implementation, if the most
 +/// significant byte is not specified, it's assumed to be 0 instead of inferring
 +/// it from the cells to the left.
 +static inline uint32_t tgetimgid(Glyph *g) {
 +	uint32_t msb = tgetimgid4thbyteplus1(g);
 +	if (msb != 0)
 +		--msb;
 +	return (msb << 24) | (g->fg & 0xFFFFFF);
 +}
 +
 +/// Sets the full image id.
 +static inline void tsetimgid(Glyph *g, uint32_t id) {
 +	g->fg = (id & 0xFFFFFF) | (1 << 24);
 +	tsetimg4thbyteplus1(g, ((id >> 24) & 0xFF) + 1);
 +}
 +
 +static inline uint32_t tgetimgplacementid(Glyph *g) {
 +	if (tgetdecorcolor(g) == DECOR_DEFAULT_COLOR)
 +		return 0;
 +	return g->decor & 0xFFFFFF;
 +}
 +
 +static inline void tsetimgplacementid(Glyph *g, uint32_t id) {
 +	g->decor = (id & 0xFFFFFF) | (1 << 24);
 +}
 diff --git a/st.info b/st.info
 index efab2cf..ded76c1 100644
 --- a/st.info
 +++ b/st.info
 @@ -195,6 +195,7 @@ st-mono| simpleterm monocolor,
  	Ms=\E]52;%p1%s;%p2%s\007,
  	Se=\E[2 q,
  	Ss=\E[%p1%d q,
 +	Smulx=\E[4:%p1%dm,
  
  st| simpleterm,
  	use=st-mono,
 @@ -215,6 +216,11 @@ st-256color| simpleterm with 256 colors,
  	initc=\E]4;%p1%d;rgb\:%p2%{255}%*%{1000}%/%2.2X/%p3%{255}%*%{1000}%/%2.2X/%p4%{255}%*%{1000}%/%2.2X\E\\,
  	setab=\E[%?%p1%{8}%<%t4%p1%d%e%p1%{16}%<%t10%p1%{8}%-%d%e48;5;%p1%d%;m,
  	setaf=\E[%?%p1%{8}%<%t3%p1%d%e%p1%{16}%<%t9%p1%{8}%-%d%e38;5;%p1%d%;m,
 +# Underline colors
 +	Su,
 +	Setulc=\E[58:2:%p1%{65536}%/%d:%p1%{256}%/%{255}%&%d:%p1%{255}%&%d%;m,
 +	Setulc1=\E[58:5:%p1%dm,
 +	ol=\E[59m,
  
  st-meta| simpleterm with meta key,
  	use=st,
 diff --git a/win.h b/win.h
 index 6de960d..31b3fff 100644
 --- a/win.h
 +++ b/win.h
 @@ -39,3 +39,6 @@ void xsetpointermotion(int);
  void xsetsel(char *);
  int xstartdraw(void);
  void xximspot(int, int);
 +
 +void xstartimagedraw(int *dirty, int rows);
 +void xfinishimagedraw();
 diff --git a/x.c b/x.c
 index d73152b..6f1bf8c 100644
 --- a/x.c
 +++ b/x.c
 @@ -4,6 +4,8 @@
  #include <limits.h>
  #include <locale.h>
  #include <signal.h>
 +#include <stdio.h>
 +#include <stdlib.h>
  #include <sys/select.h>
  #include <time.h>
  #include <unistd.h>
 @@ -19,6 +21,7 @@ char *argv0;
  #include "arg.h"
  #include "st.h"
  #include "win.h"
 +#include "graphics.h"
  
  /* types used in config.h */
  typedef struct {
 @@ -59,6 +62,12 @@ static void zoom(const Arg *);
  static void zoomabs(const Arg *);
  static void zoomreset(const Arg *);
  static void ttysend(const Arg *);
 +static void previewimage(const Arg *);
 +static void showimageinfo(const Arg *);
 +static void togglegrdebug(const Arg *);
 +static void dumpgrstate(const Arg *);
 +static void unloadimages(const Arg *);
 +static void toggleimages(const Arg *);
  
  /* config.h for applying patches and the configuration. */
  #include "config.h"
 @@ -81,6 +90,7 @@ typedef XftGlyphFontSpec GlyphFontSpec;
  typedef struct {
  	int tw, th; /* tty width and height */
  	int w, h; /* window width and height */
 +	int hborderpx, vborderpx;
  	int ch; /* char height */
  	int cw; /* char width  */
  	int mode; /* window state/mode flags */
 @@ -144,6 +154,8 @@ static inline ushort sixd_to_16bit(int);
  static int xmakeglyphfontspecs(XftGlyphFontSpec *, const Glyph *, int, int, int);
  static void xdrawglyphfontspecs(const XftGlyphFontSpec *, Glyph, int, int, int);
  static void xdrawglyph(Glyph, int, int);
 +static void xdrawimages(Glyph, Line, int x1, int y1, int x2);
 +static void xdrawoneimagecell(Glyph, int x, int y);
  static void xclear(int, int, int, int);
  static int xgeommasktogravity(int);
  static int ximopen(Display *);
 @@ -220,6 +232,7 @@ static DC dc;
  static XWindow xw;
  static XSelection xsel;
  static TermWindow win;
 +static unsigned int mouse_col = 0, mouse_row = 0;
  
  /* Font Ring Cache */
  enum {
 @@ -328,10 +341,72 @@ ttysend(const Arg *arg)
  	ttywrite(arg->s, strlen(arg->s), 1);
  }
  
 +void
 +previewimage(const Arg *arg)
 +{
 +	Glyph g = getglyphat(mouse_col, mouse_row);
 +	if (g.mode & ATTR_IMAGE) {
 +		uint32_t image_id = tgetimgid(&g);
 +		fprintf(stderr, "Clicked on placeholder %u/%u, x=%d, y=%d\n",
 +			image_id, tgetimgplacementid(&g), tgetimgcol(&g),
 +			tgetimgrow(&g));
 +		gr_preview_image(image_id, arg->s);
 +	}
 +}
 +
 +void
 +showimageinfo(const Arg *arg)
 +{
 +	Glyph g = getglyphat(mouse_col, mouse_row);
 +	if (g.mode & ATTR_IMAGE) {
 +		uint32_t image_id = tgetimgid(&g);
 +		fprintf(stderr, "Clicked on placeholder %u/%u, x=%d, y=%d\n",
 +			image_id, tgetimgplacementid(&g), tgetimgcol(&g),
 +			tgetimgrow(&g));
 +		char stcommand[256] = {0};
 +		size_t len = snprintf(stcommand, sizeof(stcommand), "%s -e less", argv0);
 +		if (len > sizeof(stcommand) - 1) {
 +			fprintf(stderr, "Executable name too long: %s\n",
 +				argv0);
 +			return;
 +		}
 +		gr_show_image_info(image_id, tgetimgplacementid(&g),
 +				   tgetimgcol(&g), tgetimgrow(&g),
 +				   tgetisclassicplaceholder(&g),
 +				   tgetimgdiacriticcount(&g), argv0);
 +	}
 +}
 +
 +void
 +togglegrdebug(const Arg *arg)
 +{
 +	graphics_debug_mode = (graphics_debug_mode + 1) % 3;
 +	redraw();
 +}
 +
 +void
 +dumpgrstate(const Arg *arg)
 +{
 +	gr_dump_state();
 +}
 +
 +void
 +unloadimages(const Arg *arg)
 +{
 +	gr_unload_images_to_reduce_ram();
 +}
 +
 +void
 +toggleimages(const Arg *arg)
 +{
 +	graphics_display_images = !graphics_display_images;
 +	redraw();
 +}
 +
  int
  evcol(XEvent *e)
  {
 -	int x = e->xbutton.x - borderpx;
 +	int x = e->xbutton.x - win.hborderpx;
  	LIMIT(x, 0, win.tw - 1);
  	return x / win.cw;
  }
 @@ -339,7 +414,7 @@ evcol(XEvent *e)
  int
  evrow(XEvent *e)
  {
 -	int y = e->xbutton.y - borderpx;
 +	int y = e->xbutton.y - win.vborderpx;
  	LIMIT(y, 0, win.th - 1);
  	return y / win.ch;
  }
 @@ -452,6 +527,9 @@ mouseaction(XEvent *e, uint release)
  	/* ignore Button<N>mask for Button<N> - it's set on release */
  	uint state = e->xbutton.state & ~buttonmask(e->xbutton.button);
  
 +	mouse_col = evcol(e);
 +	mouse_row = evrow(e);
 +
  	for (ms = mshortcuts; ms < mshortcuts + LEN(mshortcuts); ms++) {
  		if (ms->release == release &&
  		    ms->button == e->xbutton.button &&
 @@ -739,6 +817,9 @@ cresize(int width, int height)
  	col = MAX(1, col);
  	row = MAX(1, row);
  
 +	win.hborderpx = (win.w - col * win.cw) * anysize_halign / 100;
 +	win.vborderpx = (win.h - row * win.ch) * anysize_valign / 100;
 +
  	tresize(col, row);
  	xresize(col, row);
  	ttyresize(win.tw, win.th);
 @@ -869,8 +950,8 @@ xhints(void)
  	sizeh->flags = PSize | PResizeInc | PBaseSize | PMinSize;
  	sizeh->height = win.h;
  	sizeh->width = win.w;
 -	sizeh->height_inc = win.ch;
 -	sizeh->width_inc = win.cw;
 +	sizeh->height_inc = 1;
 +	sizeh->width_inc = 1;
  	sizeh->base_height = 2 * borderpx;
  	sizeh->base_width = 2 * borderpx;
  	sizeh->min_height = win.ch + 2 * borderpx;
 @@ -1014,7 +1095,8 @@ xloadfonts(const char *fontstr, double fontsize)
  			FcPatternAddDouble(pattern, FC_PIXEL_SIZE, 12);
  			usedfontsize = 12;
  		}
 -		defaultfontsize = usedfontsize;
 +		if (defaultfontsize <= 0)
 +			defaultfontsize = usedfontsize;
  	}
  
  	if (xloadfont(&dc.font, pattern))
 @@ -1024,7 +1106,7 @@ xloadfonts(const char *fontstr, double fontsize)
  		FcPatternGetDouble(dc.font.match->pattern,
  		                   FC_PIXEL_SIZE, 0, &fontval);
  		usedfontsize = fontval;
 -		if (fontsize == 0)
 +		if (defaultfontsize <= 0 && fontsize == 0)
  			defaultfontsize = fontval;
  	}
  
 @@ -1152,8 +1234,8 @@ xinit(int cols, int rows)
  	xloadcols();
  
  	/* adjust fixed window geometry */
 -	win.w = 2 * borderpx + cols * win.cw;
 -	win.h = 2 * borderpx + rows * win.ch;
 +	win.w = 2 * win.hborderpx + 2 * borderpx + cols * win.cw;
 +	win.h = 2 * win.vborderpx + 2 * borderpx + rows * win.ch;
  	if (xw.gm & XNegative)
  		xw.l += DisplayWidth(xw.dpy, xw.scr) - win.w - 2;
  	if (xw.gm & YNegative)
 @@ -1240,12 +1322,15 @@ xinit(int cols, int rows)
  	xsel.xtarget = XInternAtom(xw.dpy, "UTF8_STRING", 0);
  	if (xsel.xtarget == None)
  		xsel.xtarget = XA_STRING;
 +
 +	// Initialize the graphics (image display) module.
 +	gr_init(xw.dpy, xw.vis, xw.cmap);
  }
  
  int
  xmakeglyphfontspecs(XftGlyphFontSpec *specs, const Glyph *glyphs, int len, int x, int y)
  {
 -	float winx = borderpx + x * win.cw, winy = borderpx + y * win.ch, xp, yp;
 +	float winx = win.hborderpx + x * win.cw, winy = win.vborderpx + y * win.ch, xp, yp;
  	ushort mode, prevmode = USHRT_MAX;
  	Font *font = &dc.font;
  	int frcflags = FRC_NORMAL;
 @@ -1267,6 +1352,11 @@ xmakeglyphfontspecs(XftGlyphFontSpec *specs, const Glyph *glyphs, int len, int x
  		if (mode == ATTR_WDUMMY)
  			continue;
  
 +		/* Draw spaces for image placeholders (images will be drawn
 +		 * separately). */
 +		if (mode & ATTR_IMAGE)
 +			rune = ' ';
 +
  		/* Determine font for glyph if different from previous glyph. */
  		if (prevmode != mode) {
  			prevmode = mode;
 @@ -1374,11 +1464,61 @@ xmakeglyphfontspecs(XftGlyphFontSpec *specs, const Glyph *glyphs, int len, int x
  	return numspecs;
  }
  
 +/* Draws a horizontal dashed line of length `w` starting at `(x, y)`. `wavelen`
 + * is the length of the dash plus the length of the gap. `fraction` is the
 + * fraction of the dash length compared to `wavelen`. */
 +static void
 +xdrawunderdashed(Draw draw, Color *color, int x, int y, int w,
 +		 int wavelen, float fraction, int thick)
 +{
 +	int dashw = MAX(1, fraction * wavelen);
 +	for (int i = x - x % wavelen; i < x + w; i += wavelen) {
 +		int startx = MAX(i, x);
 +		int endx = MIN(i + dashw, x + w);
 +		if (startx < endx)
 +			XftDrawRect(xw.draw, color, startx, y, endx - startx,
 +				    thick);
 +	}
 +}
 +
 +/* Draws an undercurl. `h` is the total height, including line thickness. */
 +static void
 +xdrawundercurl(Draw draw, Color *color, int x, int y, int w, int h, int thick)
 +{
 +	XGCValues gcvals = {.foreground = color->pixel,
 +			    .line_width = thick,
 +			    .line_style = LineSolid,
 +			    .cap_style = CapRound};
 +	GC gc = XCreateGC(xw.dpy, XftDrawDrawable(xw.draw),
 +			  GCForeground | GCLineWidth | GCLineStyle | GCCapStyle,
 +			  &gcvals);
 +
 +	XRectangle clip = {.x = x, .y = y, .width = w, .height = h};
 +	XSetClipRectangles(xw.dpy, gc, 0, 0, &clip, 1, Unsorted);
 +
 +	int yoffset = thick / 2;
 +	int segh = MAX(1, h - thick);
 +	/* Make sure every segment is at a 45 degree angle, otherwise it doesn't
 +	 * look good without antialiasing. */
 +	int segw = segh;
 +	int wavelen = MAX(1, segw * 2);
 +
 +	for (int i = x - (x % wavelen); i < x + w; i += wavelen) {
 +		XPoint points[3] = {{.x = i, .y = y + yoffset},
 +				    {.x = i + segw, .y = y + yoffset + segh},
 +				    {.x = i + wavelen, .y = y + yoffset}};
 +		XDrawLines(xw.dpy, XftDrawDrawable(xw.draw), gc, points, 3,
 +			   CoordModeOrigin);
 +	}
 +
 +	XFreeGC(xw.dpy, gc);
 +}
 +
  void
  xdrawglyphfontspecs(const XftGlyphFontSpec *specs, Glyph base, int len, int x, int y)
  {
  	int charlen = len * ((base.mode & ATTR_WIDE) ? 2 : 1);
 -	int winx = borderpx + x * win.cw, winy = borderpx + y * win.ch,
 +	int winx = win.hborderpx + x * win.cw, winy = win.vborderpx + y * win.ch,
  	    width = charlen * win.cw;
  	Color *fg, *bg, *temp, revfg, revbg, truefg, truebg;
  	XRenderColor colfg, colbg;
 @@ -1468,17 +1608,17 @@ xdrawglyphfontspecs(const XftGlyphFontSpec *specs, Glyph base, int len, int x, i
  
  	/* Intelligent cleaning up of the borders. */
  	if (x == 0) {
 -		xclear(0, (y == 0)? 0 : winy, borderpx,
 +		xclear(0, (y == 0)? 0 : winy, win.hborderpx,
  			winy + win.ch +
 -			((winy + win.ch >= borderpx + win.th)? win.h : 0));
 +			((winy + win.ch >= win.vborderpx + win.th)? win.h : 0));
  	}
 -	if (winx + width >= borderpx + win.tw) {
 +	if (winx + width >= win.hborderpx + win.tw) {
  		xclear(winx + width, (y == 0)? 0 : winy, win.w,
 -			((winy + win.ch >= borderpx + win.th)? win.h : (winy + win.ch)));
 +			((winy + win.ch >= win.vborderpx + win.th)? win.h : (winy + win.ch)));
  	}
  	if (y == 0)
 -		xclear(winx, 0, winx + width, borderpx);
 -	if (winy + win.ch >= borderpx + win.th)
 +		xclear(winx, 0, winx + width, win.vborderpx);
 +	if (winy + win.ch >= win.vborderpx + win.th)
  		xclear(winx, winy + win.ch, winx + width, win.h);
  
  	/* Clean up the region we want to draw to. */
 @@ -1491,18 +1631,68 @@ xdrawglyphfontspecs(const XftGlyphFontSpec *specs, Glyph base, int len, int x, i
  	r.width = width;
  	XftDrawSetClipRectangles(xw.draw, winx, winy, &r, 1);
  
 -	/* Render the glyphs. */
 -	XftDrawGlyphFontSpec(xw.draw, fg, specs, len);
 -
 -	/* Render underline and strikethrough. */
 +	/* Decoration color. */
 +	Color decor;
 +	uint32_t decorcolor = tgetdecorcolor(&base);
 +	if (decorcolor == DECOR_DEFAULT_COLOR) {
 +		decor = *fg;
 +	} else if (IS_TRUECOL(decorcolor)) {
 +		colfg.alpha = 0xffff;
 +		colfg.red = TRUERED(decorcolor);
 +		colfg.green = TRUEGREEN(decorcolor);
 +		colfg.blue = TRUEBLUE(decorcolor);
 +		XftColorAllocValue(xw.dpy, xw.vis, xw.cmap, &colfg, &decor);
 +	} else {
 +		decor = dc.col[decorcolor];
 +	}
 +	decor.color.alpha = 0xffff;
 +	decor.pixel |= 0xff << 24;
 +
 +	/* Float thickness, used as a base to compute other values. */
 +	float fthick = dc.font.height / 18.0;
 +	/* Integer thickness in pixels. Must not be 0. */
 +	int thick = MAX(1, roundf(fthick));
 +	/* The default gap between the baseline and a single underline. */
 +	int gap = roundf(fthick * 2);
 +	/* The total thickness of a double underline. */
 +	int doubleh = thick * 2 + ceilf(fthick * 0.5);
 +	/* The total thickness of an undercurl. */
 +	int curlh = thick * 2 + roundf(fthick * 0.75);
 +
 +	/* Render the underline before the glyphs. */
  	if (base.mode & ATTR_UNDERLINE) {
 -		XftDrawRect(xw.draw, fg, winx, winy + dc.font.ascent * chscale + 1,
 -				width, 1);
 +		uint32_t style = tgetdecorstyle(&base);
 +		int liney = winy + dc.font.ascent + gap;
 +		/* Adjust liney to guarantee that a single underline fits. */
 +		liney -= MAX(0, liney + thick - (winy + win.ch));
 +		if (style == UNDERLINE_DOUBLE) {
 +			liney -= MAX(0, liney + doubleh - (winy + win.ch));
 +			XftDrawRect(xw.draw, &decor, winx, liney, width, thick);
 +			XftDrawRect(xw.draw, &decor, winx,
 +				    liney + doubleh - thick, width, thick);
 +		} else if (style == UNDERLINE_DOTTED) {
 +			xdrawunderdashed(xw.draw, &decor, winx, liney, width,
 +					 thick * 2, 0.5, thick);
 +		} else if (style == UNDERLINE_DASHED) {
 +			int wavelen = MAX(2, win.cw * 0.9);
 +			xdrawunderdashed(xw.draw, &decor, winx, liney, width,
 +					 wavelen, 0.65, thick);
 +		} else if (style == UNDERLINE_CURLY) {
 +			liney -= MAX(0, liney + curlh - (winy + win.ch));
 +			xdrawundercurl(xw.draw, &decor, winx, liney, width,
 +				       curlh, thick);
 +		} else {
 +			XftDrawRect(xw.draw, &decor, winx, liney, width, thick);
 +		}
  	}
  
 +	/* Render the glyphs. */
 +	XftDrawGlyphFontSpec(xw.draw, fg, specs, len);
 +
 +	/* Render strikethrough. Alway use the fg color. */
  	if (base.mode & ATTR_STRUCK) {
 -		XftDrawRect(xw.draw, fg, winx, winy + 2 * dc.font.ascent * chscale / 3,
 -				width, 1);
 +		XftDrawRect(xw.draw, fg, winx, winy + 2 * dc.font.ascent / 3,
 +			    width, thick);
  	}
  
  	/* Reset clip to none. */
 @@ -1517,6 +1707,11 @@ xdrawglyph(Glyph g, int x, int y)
  
  	numspecs = xmakeglyphfontspecs(&spec, &g, 1, x, y);
  	xdrawglyphfontspecs(&spec, g, numspecs, x, y);
 +	if (g.mode & ATTR_IMAGE) {
 +		gr_start_drawing(xw.buf, win.cw, win.ch);
 +		xdrawoneimagecell(g, x, y);
 +		gr_finish_drawing(xw.buf);
 +	}
  }
  
  void
 @@ -1532,6 +1727,10 @@ xdrawcursor(int cx, int cy, Glyph g, int ox, int oy, Glyph og)
  	if (IS_SET(MODE_HIDE))
  		return;
  
 +	// If it's an image, just draw a ballot box for simplicity.
 +	if (g.mode & ATTR_IMAGE)
 +		g.u = 0x2610;
 +
  	/*
  	 * Select the right color for the right mode.
  	 */
 @@ -1572,39 +1771,167 @@ xdrawcursor(int cx, int cy, Glyph g, int ox, int oy, Glyph og)
  		case 3: /* Blinking Underline */
  		case 4: /* Steady Underline */
  			XftDrawRect(xw.draw, &drawcol,
 -					borderpx + cx * win.cw,
 -					borderpx + (cy + 1) * win.ch - \
 +					win.hborderpx + cx * win.cw,
 +					win.vborderpx + (cy + 1) * win.ch - \
  						cursorthickness,
  					win.cw, cursorthickness);
  			break;
  		case 5: /* Blinking bar */
  		case 6: /* Steady bar */
  			XftDrawRect(xw.draw, &drawcol,
 -					borderpx + cx * win.cw,
 -					borderpx + cy * win.ch,
 +					win.hborderpx + cx * win.cw,
 +					win.vborderpx + cy * win.ch,
  					cursorthickness, win.ch);
  			break;
  		}
  	} else {
  		XftDrawRect(xw.draw, &drawcol,
 -				borderpx + cx * win.cw,
 -				borderpx + cy * win.ch,
 +				win.hborderpx + cx * win.cw,
 +				win.vborderpx + cy * win.ch,
  				win.cw - 1, 1);
  		XftDrawRect(xw.draw, &drawcol,
 -				borderpx + cx * win.cw,
 -				borderpx + cy * win.ch,
 +				win.hborderpx + cx * win.cw,
 +				win.vborderpx + cy * win.ch,
  				1, win.ch - 1);
  		XftDrawRect(xw.draw, &drawcol,
 -				borderpx + (cx + 1) * win.cw - 1,
 -				borderpx + cy * win.ch,
 +				win.hborderpx + (cx + 1) * win.cw - 1,
 +				win.vborderpx + cy * win.ch,
  				1, win.ch - 1);
  		XftDrawRect(xw.draw, &drawcol,
 -				borderpx + cx * win.cw,
 -				borderpx + (cy + 1) * win.ch - 1,
 +				win.hborderpx + cx * win.cw,
 +				win.vborderpx + (cy + 1) * win.ch - 1,
  				win.cw, 1);
  	}
  }
  
 +/* Draw (or queue for drawing) image cells between columns x1 and x2 assuming
 + * that they have the same attributes (and thus the same lower 24 bits of the
 + * image ID and the same placement ID). */
 +void
 +xdrawimages(Glyph base, Line line, int x1, int y1, int x2) {
 +	int y_pix = win.vborderpx + y1 * win.ch;
 +	uint32_t image_id_24bits = base.fg & 0xFFFFFF;
 +	uint32_t placement_id = tgetimgplacementid(&base);
 +	// Columns and rows are 1-based, 0 means unspecified.
 +	int last_col = 0;
 +	int last_row = 0;
 +	int last_start_col = 0;
 +	int last_start_x = x1;
 +	// The most significant byte is also 1-base, subtract 1 before use.
 +	uint32_t last_id_4thbyteplus1 = 0;
 +	// We may need to inherit row/column/4th byte from the previous cell.
 +	Glyph *prev = &line[x1 - 1];
 +	if (x1 > 0 && (prev->mode & ATTR_IMAGE) &&
 +	    (prev->fg & 0xFFFFFF) == image_id_24bits &&
 +	    prev->decor == base.decor) {
 +		last_row = tgetimgrow(prev);
 +		last_col = tgetimgcol(prev);
 +		last_id_4thbyteplus1 = tgetimgid4thbyteplus1(prev);
 +		last_start_col = last_col + 1;
 +	}
 +	for (int x = x1; x < x2; ++x) {
 +		Glyph *g = &line[x];
 +		uint32_t cur_row = tgetimgrow(g);
 +		uint32_t cur_col = tgetimgcol(g);
 +		uint32_t cur_id_4thbyteplus1 = tgetimgid4thbyteplus1(g);
 +		uint32_t num_diacritics = tgetimgdiacriticcount(g);
 +		// If the row is not specified, assume it's the same as the row
 +		// of the previous cell. Note that `cur_row` may contain a
 +		// value imputed earlier, which will be preserved if `last_row`
 +		// is zero (i.e. we don't know the row of the previous cell).
 +		if (last_row && (num_diacritics == 0 || !cur_row))
 +			cur_row = last_row;
 +		// If the column is not specified and the row is the same as the
 +		// row of the previous cell, then assume that the column is the
 +		// next one.
 +		if (last_col && (num_diacritics <= 1 || !cur_col) &&
 +		    cur_row == last_row)
 +			cur_col = last_col + 1;
 +		// If the additional id byte is not specified and the
 +		// coordinates are consecutive, assume the byte is also the
 +		// same.
 +		if (last_id_4thbyteplus1 &&
 +		    (num_diacritics <= 2 || !cur_id_4thbyteplus1) &&
 +		    cur_row == last_row && cur_col == last_col + 1)
 +			cur_id_4thbyteplus1 = last_id_4thbyteplus1;
 +		// If we couldn't infer row and column, start from the top left
 +		// corner.
 +		if (cur_row == 0)
 +			cur_row = 1;
 +		if (cur_col == 0)
 +			cur_col = 1;
 +		// If this cell breaks a contiguous stripe of image cells, draw
 +		// that line and start a new one.
 +		if (cur_col != last_col + 1 || cur_row != last_row ||
 +		    cur_id_4thbyteplus1 != last_id_4thbyteplus1) {
 +			uint32_t image_id = image_id_24bits;
 +			if (last_id_4thbyteplus1)
 +				image_id |= (last_id_4thbyteplus1 - 1) << 24;
 +			if (last_row != 0) {
 +				int x_pix =
 +					win.hborderpx + last_start_x * win.cw;
 +				gr_append_imagerect(
 +					xw.buf, image_id, placement_id,
 +					last_start_col - 1, last_col,
 +					last_row - 1, last_row, last_start_x,
 +					y1, x_pix, y_pix, win.cw, win.ch,
 +					base.mode & ATTR_REVERSE);
 +			}
 +			last_start_col = cur_col;
 +			last_start_x = x;
 +		}
 +		last_row = cur_row;
 +		last_col = cur_col;
 +		last_id_4thbyteplus1 = cur_id_4thbyteplus1;
 +		// Populate the missing glyph data to enable inheritance between
 +		// runs and support the naive implementation of tgetimgid.
 +		if (!tgetimgrow(g))
 +			tsetimgrow(g, cur_row);
 +		// We cannot save this information if there are > 511 cols.
 +		if (!tgetimgcol(g) && (cur_col & ~0x1ff) == 0)
 +			tsetimgcol(g, cur_col);
 +		if (!tgetimgid4thbyteplus1(g))
 +			tsetimg4thbyteplus1(g, cur_id_4thbyteplus1);
 +	}
 +	uint32_t image_id = image_id_24bits;
 +	if (last_id_4thbyteplus1)
 +		image_id |= (last_id_4thbyteplus1 - 1) << 24;
 +	// Draw the last contiguous stripe.
 +	if (last_row != 0) {
 +		int x_pix = win.hborderpx + last_start_x * win.cw;
 +		gr_append_imagerect(xw.buf, image_id, placement_id,
 +				    last_start_col - 1, last_col, last_row - 1,
 +				    last_row, last_start_x, y1, x_pix, y_pix,
 +				    win.cw, win.ch, base.mode & ATTR_REVERSE);
 +	}
 +}
 +
 +/* Draw just one image cell without inheriting attributes from the left. */
 +void xdrawoneimagecell(Glyph g, int x, int y) {
 +	if (!(g.mode & ATTR_IMAGE))
 +		return;
 +	int x_pix = win.hborderpx + x * win.cw;
 +	int y_pix = win.vborderpx + y * win.ch;
 +	uint32_t row = tgetimgrow(&g) - 1;
 +	uint32_t col = tgetimgcol(&g) - 1;
 +	uint32_t placement_id = tgetimgplacementid(&g);
 +	uint32_t image_id = tgetimgid(&g);
 +	gr_append_imagerect(xw.buf, image_id, placement_id, col, col + 1, row,
 +			    row + 1, x, y, x_pix, y_pix, win.cw, win.ch,
 +			    g.mode & ATTR_REVERSE);
 +}
 +
 +/* Prepare for image drawing. */
 +void xstartimagedraw(int *dirty, int rows) {
 +	gr_start_drawing(xw.buf, win.cw, win.ch);
 +	gr_mark_dirty_animations(dirty, rows);
 +}
 +
 +/* Draw all queued image cells. */
 +void xfinishimagedraw() {
 +	gr_finish_drawing(xw.buf);
 +}
 +
  void
  xsetenv(void)
  {
 @@ -1671,6 +1998,8 @@ xdrawline(Line line, int x1, int y1, int x2)
  			new.mode ^= ATTR_REVERSE;
  		if (i > 0 && ATTRCMP(base, new)) {
  			xdrawglyphfontspecs(specs, base, i, ox, y1);
 +			if (base.mode & ATTR_IMAGE)
 +				xdrawimages(base, line, ox, y1, x);
  			specs += i;
  			numspecs -= i;
  			i = 0;
 @@ -1683,6 +2012,8 @@ xdrawline(Line line, int x1, int y1, int x2)
  	}
  	if (i > 0)
  		xdrawglyphfontspecs(specs, base, i, ox, y1);
 +	if (i > 0 && base.mode & ATTR_IMAGE)
 +		xdrawimages(base, line, ox, y1, x);
  }
  
  void
 @@ -1907,6 +2238,7 @@ cmessage(XEvent *e)
  		}
  	} else if (e->xclient.data.l[0] == xw.wmdeletewin) {
  		ttyhangup();
 +		gr_deinit();
  		exit(0);
  	}
  }
 @@ -1957,6 +2289,13 @@ run(void)
  		if (XPending(xw.dpy))
  			timeout = 0;  /* existing events might not set xfd */
  
 +		/* Decrease the timeout if there are active animations. */
 +		if (graphics_next_redraw_delay != INT_MAX &&
 +		    IS_SET(MODE_VISIBLE))
 +			timeout = timeout < 0 ? graphics_next_redraw_delay
 +					      : MIN(timeout,
 +						    graphics_next_redraw_delay);
 +
  		seltv.tv_sec = timeout / 1E3;
  		seltv.tv_nsec = 1E6 * (timeout - 1E3 * seltv.tv_sec);
  		tv = timeout >= 0 ? &seltv : NULL;
 -- 
 2.43.0