cogl/frame-info: Add VSYNC flag

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1484>

4 files changed, 19 insertions, 0 deletions

diff --git a/cogl/cogl/cogl-frame-info-private.h b/cogl/cogl/cogl-frame-info-private.h
index 675b6da45..81904f7a4 100644
--- a/cogl/cogl/cogl-frame-info-private.h
+++ b/cogl/cogl/cogl-frame-info-private.h
@@ -48,6 +48,14 @@ typedef enum _CoglFrameInfoFlag
    * fullscreen surface and a surface on a hardware overlay.
    */
   COGL_FRAME_INFO_FLAG_ZERO_COPY = 1 << 2,
+  /*
+   * The presentation was synchronized to the "vertical retrace" by the display
+   * hardware such that tearing does not happen. Relying on user space
+   * scheduling is not acceptable for this flag. If presentation is done by a
+   * copy to the active frontbuffer, then it must guarantee that tearing cannot
+   * happen.
+   */
+  COGL_FRAME_INFO_FLAG_VSYNC = 1 << 3,
 } CoglFrameInfoFlag;
 
 struct _CoglFrameInfo
diff --git a/cogl/cogl/cogl-frame-info.c b/cogl/cogl/cogl-frame-info.c
index 24a100bfa..a31d91689 100644
--- a/cogl/cogl/cogl-frame-info.c
+++ b/cogl/cogl/cogl-frame-info.c
@@ -101,6 +101,12 @@ cogl_frame_info_is_zero_copy (CoglFrameInfo *info)
   return !!(info->flags & COGL_FRAME_INFO_FLAG_ZERO_COPY);
 }
 
+gboolean
+cogl_frame_info_is_vsync (CoglFrameInfo *info)
+{
+  return !!(info->flags & COGL_FRAME_INFO_FLAG_VSYNC);
+}
+
 unsigned int
 cogl_frame_info_get_sequence (CoglFrameInfo *info)
 {
diff --git a/cogl/cogl/cogl-frame-info.h b/cogl/cogl/cogl-frame-info.h
index 62a9bb0ea..7278a08ca 100644
--- a/cogl/cogl/cogl-frame-info.h
+++ b/cogl/cogl/cogl-frame-info.h
@@ -145,6 +145,9 @@ COGL_EXPORT
 gboolean cogl_frame_info_is_zero_copy (CoglFrameInfo *info);
 
 COGL_EXPORT
+gboolean cogl_frame_info_is_vsync (CoglFrameInfo *info);
+
+COGL_EXPORT
 unsigned int cogl_frame_info_get_sequence (CoglFrameInfo *info);
 
 G_END_DECLS
diff --git a/cogl/cogl/winsys/cogl-onscreen-glx.c b/cogl/cogl/winsys/cogl-onscreen-glx.c
index df8922b5d..8bbb508b7 100644
--- a/cogl/cogl/winsys/cogl-onscreen-glx.c
+++ b/cogl/cogl/winsys/cogl-onscreen-glx.c
@@ -472,6 +472,7 @@ _cogl_winsys_wait_for_vblank (CoglOnscreen *onscreen)
   if (glx_display->can_vblank_wait)
     {
       CoglFrameInfo *info = cogl_onscreen_peek_tail_frame_info (onscreen);
+      info->flags |= COGL_FRAME_INFO_FLAG_VSYNC;
 
       if (glx_renderer->glXWaitForMsc)
         {
@@ -987,6 +988,7 @@ cogl_onscreen_glx_notify_swap_buffers (CoglOnscreen          *onscreen,
   set_sync_pending (onscreen);
 
   info = cogl_onscreen_peek_head_frame_info (onscreen);
+  info->flags |= COGL_FRAME_INFO_FLAG_VSYNC;
 
   ust_is_monotonic = is_ust_monotonic (context->display->renderer,
                                        onscreen_glx->glxwin);