vo_opengl_cb: don't wait for redrawn frames

This also removes some extra waiting if no video is active, at least in
theory.

Also clarify the vo_frame flag comments for redraw/repeat.

2 files changed, 6 insertions, 3 deletions

diff --git a/video/out/vo.h b/video/out/vo.h
index 5dbdc3fa89..d2393f829b 100644
--- a/video/out/vo.h
+++ b/video/out/vo.h
@@ -196,8 +196,10 @@ struct vo_frame {
     // Set if the current frame is repeated from the previous. It's guaranteed
     // that the current is the same as the previous one, even if the image
     // pointer is different.
-    // The repeat flag is additionally set if the OSD does not need to be
-    // redrawn.
+    // The repeat flag is set if exactly the same frame should be rendered
+    // again (and the OSD does not need to be redrawn).
+    // A repeat frame can be redrawn, in which case repeat==redraw==true, and
+    // OSD should be updated.
     bool redraw, repeat;
     // The frame is not in movement - e.g. redrawing while paused.
     bool still;
diff --git a/video/out/vo_opengl_cb.c b/video/out/vo_opengl_cb.c
index c94d8b7ce8..20e9523cb0 100644
--- a/video/out/vo_opengl_cb.c
+++ b/video/out/vo_opengl_cb.c
@@ -296,7 +296,8 @@ int mpv_opengl_cb_draw(mpv_opengl_cb_context *ctx, int fbo, int vp_w, int vp_h)
     int64_t wait_present_count = ctx->present_count;
     if (frame) {
         ctx->next_frame = NULL;
-        wait_present_count += 1;
+        if (frame->redraw || !frame->current)
+            wait_present_count += 1;
         pthread_cond_signal(&ctx->wakeup);
         talloc_free(ctx->cur_frame);
         ctx->cur_frame = vo_frame_ref(frame);