x11: use new option stuff to implement fullscreen

- remove VOCTRL_FULLSCREEN and VOCTRL_GET_FULLSCREEN
- have your own m_config_cache for the fullscreen option
  (vo->opts_cache cannot be used because you lose per-option change
  notifications, and it'd be a mess anyway)
- use VOCTRL_VO_OPTS_CHANGED to update it
  (it's used for convenience)
- when updating it, check for the fullscreen option
  (wasn't sure how to do it best; currently, it compares the raw
  option pointers, but this could be changed)
- do not send VO_EVENT_FULLSCREEN_STATE on FS change
- instead write the option on FS change
  (assign in opt. struct + m_config_cache_write_opt)

video/out/vo.c

@@ -228,9 +228,12 @@ static void update_opts(void *p)
     if (m_config_cache_update(vo->opts_cache)) {
         read_opts(vo);
 
-        // "Legacy" update of video position related options.
-        if (vo->driver->control)
+        if (vo->driver->control) {
+            vo->driver->control(vo, VOCTRL_VO_OPTS_CHANGED, NULL);
+            // "Legacy" update of video position related options.
+            // Unlike VOCTRL_VO_OPTS_CHANGED, often not propagated to backends.
             vo->driver->control(vo, VOCTRL_SET_PANSCAN, NULL);
+        }
     }
 
     if (vo->gl_opts_cache && m_config_cache_update(vo->gl_opts_cache)) {

video/out/vo.h

@@ -43,7 +43,8 @@ enum {
     VO_EVENT_AMBIENT_LIGHTING_CHANGED   = 1 << 4,
     // Special mechanism for making resizing with Cocoa react faster
     VO_EVENT_LIVE_RESIZING              = 1 << 5,
-    // Window fullscreen state changed via external influence.
+    // Legacy. Use m_config_cache_write_opt() instead to update the fullscreen
+    // option.
     VO_EVENT_FULLSCREEN_STATE           = 1 << 6,
     // Special thing for encode mode (vo_driver.initially_blocked).
     // Part of VO_EVENTS_USER to make vo_is_ready_for_frame() work properly.
@@ -67,6 +68,10 @@ enum mp_voctrl {
     VOCTRL_SET_PANSCAN,
     VOCTRL_SET_EQUALIZER,
 
+    // Trigger by any change to mp_vo_opts. This is for convenience. In theory,
+    // you could install your own listener.
+    VOCTRL_VO_OPTS_CHANGED,
+
     /* private to vo_gpu */
     VOCTRL_LOAD_HWDEC_API,
 
@@ -80,12 +85,13 @@ enum mp_voctrl {
     VOCTRL_UNINIT,
     VOCTRL_RECONFIG,
 
+    // Legacy stuff.
     VOCTRL_FULLSCREEN,
     VOCTRL_ONTOP,
     VOCTRL_BORDER,
     VOCTRL_ALL_WORKSPACES,
-
     VOCTRL_GET_FULLSCREEN,
+    VOCTRL_GET_WIN_STATE,               // int* (VO_WIN_STATE_* flags)
 
     VOCTRL_UPDATE_WINDOW_TITLE,         // char*
     VOCTRL_UPDATE_PLAYBACK_STATE,       // struct voctrl_playback_state*
@@ -102,8 +108,6 @@ enum mp_voctrl {
     VOCTRL_GET_UNFS_WINDOW_SIZE,        // int[2] (w/h)
     VOCTRL_SET_UNFS_WINDOW_SIZE,        // int[2] (w/h)
 
-    VOCTRL_GET_WIN_STATE,               // int* (VO_WIN_STATE_* flags)
-
     // char *** (NULL terminated array compatible with CONF_TYPE_STRING_LIST)
     // names for displays the window is on
     VOCTRL_GET_DISPLAY_NAMES,

video/out/x11_common.c

@@ -562,8 +562,9 @@ int vo_x11_init(struct vo *vo)
         .xrandr_event = -1,
         .wakeup_pipe = {-1, -1},
         .dpi_scale = 1,
-        .opts = vo->opts,
+        .opts_cache = m_config_cache_alloc(x11, vo->global, &vo_sub_opts),
     };
+    x11->opts = x11->opts_cache->opts;
     vo->x11 = x11;
 
     sem_init(&x11->screensaver_sem, 0, 0);
@@ -1040,7 +1041,7 @@ static void vo_x11_check_net_wm_state_fullscreen_change(struct vo *vo)
         {
             x11->opts->fullscreen = is_fullscreen;
             x11->fs = is_fullscreen;
-            x11->pending_vo_events |= VO_EVENT_FULLSCREEN_STATE;
+            m_config_cache_write_opt(x11->opts_cache, &x11->opts->fullscreen);
 
             if (!is_fullscreen && (x11->pos_changed_during_fs ||
                                    x11->size_changed_during_fs))
@@ -1214,7 +1215,6 @@ void vo_x11_check_events(struct vo *vo)
                     x11->pseudo_mapped = true;
                 }
             } else if (Event.xproperty.atom == XA(x11, _NET_WM_STATE)) {
-                x11->pending_vo_events |= VO_EVENT_WIN_STATE;
                 vo_x11_check_net_wm_state_fullscreen_change(vo);
             } else if (Event.xproperty.atom == x11->icc_profile_property) {
                 x11->pending_vo_events |= VO_EVENT_ICC_PROFILE_CHANGED;
@@ -1820,12 +1820,14 @@ int vo_x11_control(struct vo *vo, int *events, int request, void *arg)
         *events |= x11->pending_vo_events;
         x11->pending_vo_events = 0;
         return VO_TRUE;
-    case VOCTRL_FULLSCREEN:
-        vo_x11_fullscreen(vo);
-        return VO_TRUE;
-    case VOCTRL_GET_FULLSCREEN:
-        *(int *)arg = x11->fs;
+    case VOCTRL_VO_OPTS_CHANGED: {
+        void *opt;
+        while (m_config_cache_get_next_changed(x11->opts_cache, &opt)) {
+            if (opt == &opts->fullscreen)
+                vo_x11_fullscreen(vo);
+        }
         return VO_TRUE;
+    }
     case VOCTRL_ONTOP:
         vo_x11_setlayer(vo, opts->ontop);
         return VO_TRUE;

video/out/x11_common.h

@@ -50,6 +50,7 @@ struct xrandr_display {
 struct vo_x11_state {
     struct mp_log *log;
     struct input_ctx *input_ctx;
+    struct m_config_cache *opts_cache;
     struct mp_vo_opts *opts;
     Display *display;
     int event_fd;