vo_sixel: Alias/deprecate exit-clear -> alt-screen

Also update documentation to reflect actual behavior.

DOCS/interface-changes.rst

@@ -28,8 +28,11 @@ Interface changes
 
  --- mpv 0.36.0 ---
     - add `--force-render`
-    - add `--vo-sixel-draw-clear` and `--vo-sixel-buffered`
+    - add `--vo-sixel-draw-clear`, `--vo-sixel-alt-screen` and
+      `--vo-sixel-buffered`
     - add `--wayland-content-type`
+    - deprecate `--vo-sixel-exit-clear` and alias it to
+      `--vo-sixel-alt-screen`
     - deprecate `--drm-atomic`
  --- mpv 0.35.0 ---
     - add the `--vo=gpu-next` video output driver, as well as the options

DOCS/man/vo.rst

@@ -438,10 +438,13 @@ Available video output drivers are:
     ``--vo-sixel-draw-clear=<yes|no>`` (default: yes)
         Whether or not to clear the terminal while drawing frames.
 
-    ``--vo-sixel-exit-clear=<yes|no>`` (default: yes)
-        Whether or not to clear the terminal on quit. When set to no - the
-        last sixel image stays on screen after quit, with the cursor following
-        it.
+    ``--vo-sixel-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
+        sixel image stays on screen after quit, with the cursor following it.
+
+        ``--vo-sixel-exit-clear`` is a deprecated alias for this option and
+        may be removed in the future.
 
     ``--vo-sixel-buffered=<yes|no>`` (default: no)
         Buffers the full output sequence before writing it to the terminal.

video/out/vo_sixel.c

@@ -56,7 +56,7 @@ struct vo_sixel_opts {
     int width, height, top, left;
     int pad_y, pad_x;
     int rows, cols;
-    int draw_clear, exit_clear;
+    int draw_clear, alt_screen;
     int buffered;
 };
 
@@ -504,7 +504,7 @@ static int preinit(struct vo *vo)
 
     sixel_output_set_encode_policy(priv->output, SIXEL_ENCODEPOLICY_FAST);
 
-    if (priv->opts.exit_clear)
+    if (priv->opts.alt_screen)
         sixel_strwrite(TERM_ESC_SAVE_SCREEN);
 
     sixel_strwrite(TERM_ESC_HIDE_CURSOR);
@@ -548,7 +548,7 @@ static void uninit(struct vo *vo)
 
     sixel_strwrite(TERM_ESC_RESTORE_CURSOR);
 
-    if (priv->opts.exit_clear)
+    if (priv->opts.alt_screen)
         sixel_strwrite(TERM_ESC_RESTORE_SCREEN);
     fflush(stdout);
 
@@ -587,7 +587,7 @@ const struct vo_driver video_out_sixel = {
         .opts.rows = 0,
         .opts.cols = 0,
         .opts.draw_clear = 1,
-        .opts.exit_clear = 1,
+        .opts.alt_screen = 1,
         .opts.buffered = 0,
     },
     .options = (const m_option_t[]) {
@@ -613,7 +613,9 @@ const struct vo_driver video_out_sixel = {
         {"rows", OPT_INT(opts.rows)},
         {"cols", OPT_INT(opts.cols)},
         {"draw-clear", OPT_FLAG(opts.draw_clear), },
-        {"exit-clear", OPT_FLAG(opts.exit_clear), },
+        {"exit-clear", OPT_FLAG(opts.alt_screen),
+            .deprecation_message = "replaced by --vo-sixel-alt-screen"},
+        {"alt-screen", OPT_FLAG(opts.alt_screen), },
         {"buffered", OPT_FLAG(opts.buffered), },
         {0}
     },