vo: move display-fps internal option value to VO opts

Removes the awkward notification through VO_EVENT_WIN_STATE.
Unfortunately, some awkwardness remains in mp_property_display_fps(),
because the property has conflicting semantics with the option.

options/options.c

@@ -139,6 +139,7 @@ static const m_option_t mp_vo_opt_list[] = {
     OPT_FLAG("keepaspect-window", keepaspect_window, 0),
     OPT_FLAG("hidpi-window-scale", hidpi_window_scale, 0),
     OPT_FLAG("native-fs", native_fs, 0),
+    OPT_DOUBLE("display-fps", override_display_fps, M_OPT_MIN, .min = 0),
     OPT_DOUBLERANGE("video-timing-offset", timing_offset, 0, 0.0, 1.0),
 #if HAVE_X11
     OPT_CHOICE("x11-netwm", x11_netwm, 0,
@@ -612,8 +613,6 @@ const m_option_t mp_opts[] = {
                 {"decoder+vo", 3})),
     OPT_FLAG("video-latency-hacks", video_latency_hacks, 0),
 
-    OPT_DOUBLE("display-fps", frame_drop_fps, M_OPT_MIN, .min = 0),
-
     OPT_FLAG("untimed", untimed, 0),
 
     OPT_STRING("stream-dump", stream_dump, M_OPT_FILE),

options/options.h

@@ -50,6 +50,7 @@ typedef struct mp_vo_opts {
 
     char *mmcss_profile;
 
+    double override_display_fps;
     double timing_offset;
 
     // vo_drm
@@ -224,7 +225,6 @@ typedef struct MPOpts {
     int autosync;
     int frame_dropping;
     int video_latency_hacks;
-    double frame_drop_fps;
     int term_osd;
     int term_osd_bar;
     char *term_osd_bar_chars;

player/command.c

@@ -2724,17 +2724,10 @@ static int mp_property_display_fps(void *ctx, struct m_property *prop,
                                    int action, void *arg)
 {
     MPContext *mpctx = ctx;
-    double fps = mpctx->opts->frame_drop_fps;
+    double fps = mpctx->video_out ? vo_get_display_fps(mpctx->video_out) : 0;
-    struct vo *vo = mpctx->video_out;
+    if (fps > 0 && action != M_PROPERTY_SET)
-    if (vo)
+        return m_property_double_ro(action, arg, fps);
-        fps = vo_get_display_fps(vo);
+    return mp_property_generic_option(mpctx, prop, action, arg);
-    if (action == M_PROPERTY_SET) {
-        int ret = mp_property_generic_option(mpctx, prop, action, arg);
-        if (vo)
-            vo_event(vo, VO_EVENT_WIN_STATE);
-        return ret;
-    }
-    return m_property_double_ro(action, arg, fps);
 }
 
 static int mp_property_framedrop(void *ctx, struct m_property *prop,

video/out/vo.c

@@ -163,6 +163,7 @@ struct vo_internal {
     uint64_t current_frame_id;
 
     double display_fps;
+    double reported_display_fps;
     int opt_framedrop;
 };
 
@@ -533,27 +534,30 @@ static void update_display_fps(struct vo *vo)
         mp_read_option_raw(vo->global, "framedrop", &m_option_type_choice,
                            &in->opt_framedrop);
 
-        double display_fps;
+        double fps = 0;
-        mp_read_option_raw(vo->global, "display-fps", &m_option_type_double,
+        vo->driver->control(vo, VOCTRL_GET_DISPLAY_FPS, &fps);
-                           &display_fps);
-
-        if (display_fps <= 0)
-            vo->driver->control(vo, VOCTRL_GET_DISPLAY_FPS, &display_fps);
 
         pthread_mutex_lock(&in->lock);
 
-        if (in->display_fps != display_fps) {
+        in->reported_display_fps = fps;
-            in->display_fps = display_fps;
-            MP_VERBOSE(vo, "Assuming %f FPS for display sync.\n", display_fps);
-
-            // make sure to update the player
-            in->queued_events |= VO_EVENT_WIN_STATE;
-            wakeup_core(vo);
-        }
-
-        in->nominal_vsync_interval = in->display_fps > 0 ? 1e6 / in->display_fps : 0;
-        in->vsync_interval = MPMAX(in->nominal_vsync_interval, 1);
     }
+
+    double display_fps = vo->opts->override_display_fps;
+    if (display_fps <= 0)
+        display_fps = in->reported_display_fps;
+
+    if (in->display_fps != display_fps) {
+        in->nominal_vsync_interval =  display_fps > 0 ? 1e6 / display_fps : 0;
+        in->vsync_interval = MPMAX(in->nominal_vsync_interval, 1);
+        in->display_fps = display_fps;
+
+        MP_VERBOSE(vo, "Assuming %f FPS for display sync.\n", display_fps);
+
+        // make sure to update the player
+        in->queued_events |= VO_EVENT_WIN_STATE;
+        wakeup_core(vo);
+    }
+
     pthread_mutex_unlock(&in->lock);
 }