vo_wayland: share frame callbacks.

Define frame callback logic in wayland_common.c
As this should be used by opengl renderer as well.

Preferably drawing should be skipped entierly when no frame callbacks
are received. However, for now only swap buffers is skipped.

video/out/gl_wayland.c

@@ -196,7 +196,12 @@ static void releaseGlContext_wayland(MPGLContext *ctx)
 static void swapGlBuffers_wayland(MPGLContext *ctx)
 {
     struct vo_wayland_state *wl = ctx->vo->wayland;
+
+    if (!wl->frame.pending)
+        return;
+
     eglSwapBuffers(wl->egl_context.egl.dpy, wl->egl_context.egl_surface);
+    wl->frame.pending = false;
 }
 
 static int control(struct vo *vo, int *events, int request, void *data)

video/out/vo_wayland.c

@@ -41,7 +41,6 @@
 static void draw_image(struct vo *vo, mp_image_t *mpi);
 static void draw_osd(struct vo *vo);
 
-static const struct wl_callback_listener frame_listener;
 static const struct wl_buffer_listener buffer_listener;
 
 // TODO: pay attention to the reported subpixel order
@@ -119,8 +118,6 @@ struct priv {
     struct mp_sws_context *sws;
     struct mp_image_params in_format;
 
-    struct wl_callback *redraw_callback;
-
     struct buffer_pool video_bufpool;
 
     struct mp_image *original_image;
@@ -359,34 +356,6 @@ static const struct wl_buffer_listener buffer_listener = {
     buffer_handle_release
 };
 
-static void frame_handle_redraw(void *data,
-                                struct wl_callback *callback,
-                                uint32_t time)
-{
-    struct priv *p = data;
-    struct vo_wayland_state *wl = p->wl;
-    shm_buffer_t *buf = buffer_pool_get_front(&p->video_bufpool);
-
-    wl_surface_attach(wl->window.video_surface, buf->buffer, p->x, p->y);
-    wl_surface_damage(wl->window.video_surface, 0, 0, p->dst_w, p->dst_h);
-
-    if (callback)
-        wl_callback_destroy(callback);
-
-    p->redraw_callback = wl_surface_frame(wl->window.video_surface);
-    wl_callback_add_listener(p->redraw_callback, &frame_listener, p);
-    wl_surface_commit(wl->window.video_surface);
-    buffer_finalise_front(buf);
-
-    p->x = 0;
-    p->y = 0;
-    p->recent_flip_time = mp_time_us();
-}
-
-static const struct wl_callback_listener frame_listener = {
-    frame_handle_redraw
-};
-
 static void shm_handle_format(void *data,
                               struct wl_shm *wl_shm,
                               uint32_t format)
@@ -414,13 +383,17 @@ static const struct wl_shm_listener shm_listener = {
 static void draw_image(struct vo *vo, mp_image_t *mpi)
 {
     struct priv *p = vo->priv;
-    shm_buffer_t *buf = buffer_pool_get_back(&p->video_bufpool);
 
     if (mpi) {
         talloc_free(p->original_image);
         p->original_image = mpi;
     }
 
+    if (!p->wl->frame.pending)
+        return;
+
+    shm_buffer_t *buf = buffer_pool_get_back(&p->video_bufpool);
+
     if (!buf) {
         // TODO: use similar handling of busy buffers as the osd buffers
         // if the need arises
@@ -535,12 +508,21 @@ static void flip_page(struct vo *vo)
 {
     struct priv *p = vo->priv;
 
+    if (!p->wl->frame.pending)
+        return;
+
     buffer_pool_swap(&p->video_bufpool);
 
-    if (!p->redraw_callback) {
-        MP_DBG(p->wl, "restart frame callback\n");
-        frame_handle_redraw(p, NULL, 0);
-    }
+    shm_buffer_t *buf = buffer_pool_get_front(&p->video_bufpool);
+    wl_surface_attach(p->wl->window.video_surface, buf->buffer, p->x, p->y);
+    wl_surface_damage(p->wl->window.video_surface, 0, 0, p->dst_w, p->dst_h);
+    wl_surface_commit(p->wl->window.video_surface);
+    buffer_finalise_front(buf);
+
+    p->x = 0;
+    p->y = 0;
+    p->recent_flip_time = mp_time_us();
+    p->wl->frame.pending = false;
 }
 
 static int query_format(struct vo *vo, int format)
@@ -612,9 +594,6 @@ static void uninit(struct vo *vo)
     struct priv *p = vo->priv;
     buffer_pool_destroy(&p->video_bufpool);
 
-    if (p->redraw_callback)
-        wl_callback_destroy(p->redraw_callback);
-
     talloc_free(p->original_image);
 
     for (int i = 0; i < MAX_OSD_PARTS; ++i) {

video/out/wayland_common.c

@@ -59,6 +59,8 @@ static void schedule_resize(struct vo_wayland_state *wl,
 
 static void vo_wayland_fullscreen (struct vo *vo);
 
+static const struct wl_callback_listener frame_listener;
+
 static const struct mp_keymap keymap[] = {
     // special keys
     {XKB_KEY_Pause,     MP_KEY_PAUSE}, {XKB_KEY_Escape, MP_KEY_ESC},
@@ -795,6 +797,30 @@ static void schedule_resize(struct vo_wayland_state *wl,
     wl->vo->dheight = height;
 }
 
+static void frame_callback(void *data,
+                           struct wl_callback *callback,
+                           uint32_t time)
+{
+    struct vo_wayland_state *wl = data;
+
+    if (callback)
+        wl_callback_destroy(callback);
+
+    wl->frame.callback = wl_surface_frame(wl->window.video_surface);
+
+    if (!wl->frame.callback) {
+        MP_ERR(wl, "wl_surface_frame failed\n");
+        return;
+    }
+
+    wl_callback_add_listener(wl->frame.callback, &frame_listener, wl);
+    wl->frame.pending = true;
+}
+
+static const struct wl_callback_listener frame_listener = {
+    frame_callback
+};
+
 static bool create_display (struct vo_wayland_state *wl)
 {
     if (wl->vo->probing && !getenv("XDG_RUNTIME_DIR"))
@@ -878,6 +904,7 @@ static bool create_window (struct vo_wayland_state *wl)
         wl_shell_surface_set_class(wl->window.shell_surface, "mpv");
     }
 
+    frame_callback(wl, NULL, 0);
     return true;
 }
 
@@ -888,6 +915,9 @@ static void destroy_window (struct vo_wayland_state *wl)
 
     if (wl->window.video_surface)
         wl_surface_destroy(wl->window.video_surface);
+
+    if (wl->frame.callback)
+        wl_callback_destroy(wl->frame.callback);
 }
 
 static bool create_cursor (struct vo_wayland_state *wl)

video/out/wayland_common.h

@@ -52,6 +52,11 @@ struct vo_wayland_state {
     struct vo *vo;
     struct mp_log* log;
 
+    struct {
+        struct wl_callback *callback;
+        bool pending;
+    } frame;
+
 #if HAVE_GL_WAYLAND
     struct {
         EGLSurface egl_surface;