vo: add a unique frame_id to vo_frame

We think that this allows simpler logic than using the redraw and repeat
fields. Not used yet.

1 files changed, 6 insertions, 0 deletions

diff --git a/video/out/vo.h b/video/out/vo.h
index e35085c49b..d76329ffeb 100644
--- a/video/out/vo.h
+++ b/video/out/vo.h
@@ -211,6 +211,12 @@ struct vo_frame {
     // VO if frames are dropped.
     int num_frames;
     struct mp_image *frames[VO_MAX_REQ_FRAMES];
+    // ID for frames[0] (== current). If current==NULL, the number is
+    // meaningless. Otherwise, it's an unique ID for the frame. The ID for
+    // a frame is guaranteed not to change (instant redraws will use the same
+    // ID). frames[n] has the ID frame_id+n, with the guarantee that frame
+    // drops or reconfigs will keep the guarantee.
+    uint64_t frame_id;
 };
 
 struct vo_driver {