client API: add events for video and audio reconfig

DOCS/man/en/lua.rst

@@ -391,3 +391,9 @@ List of events
 
 ``client-message``
     Undocumented (used internally).
+
+``video-reconfig``
+    Happens on video output or filter reconfig.
+
+``audio-reconfig``
+    Happens on audio output or filter reconfig.

libmpv/client.h

@@ -622,6 +622,22 @@ typedef enum mpv_event_id {
      * the seconand argument as strings.
      */
     MPV_EVENT_CLIENT_MESSAGE    = 16,
+    /**
+     * Happens after video changed in some way. This can happen on resolution
+     * changes, pixel format changes, or video filter changes. The event is
+     * sent after the video filters and the VO are reconfigured. Applications
+     * embedding a mpv window should listen to this event in order to resize
+     * the window if needed.
+     * Note that this event can happen sporadically, and you should check
+     * yourself whether the video parameters really changed before doing
+     * something expensive.
+     */
+    MPV_EVENT_VIDEO_RECONFIG    = 17,
+    /**
+     * Similar to MPV_EVENT_VIDEO_RECONFIG. This is relatively uninteresting,
+     * because there is no such thing as audio output embedding.
+     */
+    MPV_EVENT_AUDIO_RECONFIG    = 18,
 } mpv_event_id;
 
 /**

player/audio.c

@@ -39,6 +39,7 @@
 #include "video/decode/dec_video.h"
 
 #include "core.h"
+#include "command.h"
 
 static int build_afilter_chain(struct MPContext *mpctx)
 {
@@ -111,6 +112,8 @@ void reinit_audio_chain(struct MPContext *mpctx)
         goto no_audio;
     }
 
+    mp_notify(mpctx, MPV_EVENT_AUDIO_RECONFIG, NULL);
+
     if (!(mpctx->initialized_flags & INITIALIZED_ACODEC)) {
         mpctx->initialized_flags |= INITIALIZED_ACODEC;
         assert(!mpctx->d_audio);

player/client.c

@@ -842,6 +842,8 @@ static const char *event_table[] = {
     [MPV_EVENT_TICK] = "tick",
     [MPV_EVENT_SCRIPT_INPUT_DISPATCH] = "script-input-dispatch",
     [MPV_EVENT_CLIENT_MESSAGE] = "client-message",
+    [MPV_EVENT_VIDEO_RECONFIG] = "video-reconfig",
+    [MPV_EVENT_AUDIO_RECONFIG] = "audio-reconfig",
 };
 
 const char *mpv_event_name(mpv_event_id event)

player/core.h

@@ -21,6 +21,8 @@
 
 #include <stdbool.h>
 
+#include "libmpv/client.h"
+
 #include "common/common.h"
 #include "options/options.h"
 #include "sub/osd.h"

player/playloop.c

@@ -51,7 +51,6 @@
 #include "core.h"
 #include "screenshot.h"
 #include "command.h"
-#include "libmpv/client.h"
 
 #define WAKEUP_PERIOD 0.5
 
@@ -893,6 +892,7 @@ void handle_force_window(struct MPContext *mpctx, bool reconfig)
         };
         vo_reconfig(vo, &p, 0);
         redraw_osd(mpctx);
+        mp_notify(mpctx, MPV_EVENT_VIDEO_RECONFIG, NULL);
     }
 }
 

player/video.c

@@ -72,6 +72,10 @@ static void reconfig_video(struct MPContext *mpctx,
 
     set_allowed_vo_formats(d_video->vfilter, mpctx->video_out);
 
+    // The event should happen _after_ filter and VO reconfig. Since we don't
+    // have any fine grained locking, this is just as good.
+    mp_notify(mpctx, MPV_EVENT_VIDEO_RECONFIG, NULL);
+
     if (video_reconfig_filters(d_video, params) < 0) {
         // Most video filters don't work with hardware decoding, so this
         // might be the reason filter reconfig failed.