vo_kitty: Introduce modern sixel alternative

See https://sw.kovidgoyal.net/kitty/graphics-protocol/

This makes no attempt at querying terminal features or handling
terminal errors, as it would require mpv to pass the response codes
from the terminal to the vo instead of interpreting them as
keystrokes made by the user and acting very unpredictably.

Tested with kitty and konsole.

Fixes #9605

Author: mia-0

DOCS/interface-changes.rst

@@ -27,6 +27,11 @@ Interface changes
 ::
 
  --- mpv 0.36.0 ---
+    - add the `--vo=kitty` video output driver, as well as the options
+      `--vo-kitty-cols`, `--vo-kitty-rows`, `--vo-kitty-width`,
+      `--vo-kitty-height`, `--vo-kitty-left`, `--vo-kitty-top`,
+      `--vo-kitty-config-clear`, `--vo-kitty-alt-screen` and
+      `--vo-kitty-use-shm`
     - add `--force-render`
     - add `--vo-sixel-config-clear`, `--vo-sixel-alt-screen` and
       `--vo-sixel-buffered`

DOCS/man/vo.rst

@@ -383,6 +383,45 @@ Available video output drivers are:
     ``--vo-tct-256=<yes|no>`` (default: no)
         Use 256 colors - for terminals which don't support true color.
 
+``kitty``
+    Graphical output for the terminal, using the kitty graphics protocol.
+    Tested with kitty and Konsole.
+
+    You may need to use ``--profile=sw-fast`` to get decent performance.
+
+    Kitty size and alignment options:
+
+    ``--vo-kitty-cols=<columns>``, ``--vo-kitty-rows=<rows>`` (default: 0)
+        Specify the terminal size in character cells, otherwise (0) read it
+        from the terminal, or fall back to 80x25.
+
+    ``--vo-kitty-width=<width>``, ``--vo-kitty-height=<height>`` (default: 0)
+        Specify the available size in pixels, otherwise (0) read it from the
+        terminal, or fall back to 320x240.
+
+    ``--vo-kitty-left=<col>``, ``--vo-kitty-top=<row>`` (default: 0)
+        Specify the position in character cells where the image starts (1 is
+        the first column or row). If 0 (default) then try to automatically
+        determine it according to the other values and the image aspect ratio
+        and zoom.
+
+    ``--vo-kitty-config-clear=<yes|no>`` (default: yes)
+        Whether or not to clear the terminal whenever the output is
+        reconfigured (e.g. when video size changes).
+
+    ``--vo-kitty-alt-screen=<yes|no>`` (default: yes)
+        Whether or not to use the alternate screen buffer and return the
+        terminal to its previous state on exit. When set to no, the last
+        kitty image stays on screen after quit, with the cursor following it.
+
+    ``--vo-kitty-use-shm=<yes|no>`` (default: no)
+        Use shared memory objects to transfer image data to the terminal.
+        This is much faster than sending the data as escape codes, but is not
+        supported by as many terminals. It also only works on the local machine
+        and not via e.g. SSH connections.
+
+        This option is not implemented on Windows.
+
 ``sixel``
     Graphical output for the terminal, using sixels. Tested with ``mlterm`` and
     ``xterm``.

meson.build

@@ -229,6 +229,7 @@ sources = files(
     'video/out/vo_libmpv.c',
     'video/out/vo_null.c',
     'video/out/vo_tct.c',
+    'video/out/vo_kitty.c',
     'video/out/win_state.c',
     'video/repack.c',
     'video/sws_utils.c',

video/out/vo.c

@@ -67,6 +67,7 @@ extern const struct vo_driver video_out_wlshm;
 extern const struct vo_driver video_out_rpi;
 extern const struct vo_driver video_out_tct;
 extern const struct vo_driver video_out_sixel;
+extern const struct vo_driver video_out_kitty;
 
 const struct vo_driver *const video_out_drivers[] =
 {
@@ -118,6 +119,7 @@ const struct vo_driver *const video_out_drivers[] =
 #if HAVE_SIXEL
     &video_out_sixel,
 #endif
+    &video_out_kitty,
     &video_out_lavc,
     NULL
 };