From: Matthias Clasen <mclasen@redhat.com>
Date: Tue, 25 Apr 2023 09:44:21 +0000 (+0200)
Subject: gstreamer: Defer the sync
X-Git-Tag: archive/raspbian/4.12.3+ds-1+rpi1~1^2^2^2~22^2~1^2~354^2~1
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=b9a7e5fa8580d59b3b2eac195c75d1b9617425b2;p=gtk4.git

gstreamer: Defer the sync

Don't sync right when we receive the buffer,
pass it along with the texture to be executed
later in the renderer.
---

diff --git a/modules/media/gtkgstsink.c b/modules/media/gtkgstsink.c
index f0a15390f7..aee5cc452a 100644
--- a/modules/media/gtkgstsink.c
+++ b/modules/media/gtkgstsink.c
@@ -290,18 +290,21 @@ gtk_gst_sink_texture_from_buffer (GtkGstSink *self,
       GdkGLTextureBuilder *builder;
 
       sync_meta = gst_buffer_get_gl_sync_meta (buffer);
-      if (sync_meta) {
+      if (sync_meta)
         gst_gl_sync_meta_set_sync_point (sync_meta, self->gst_context);
-        gst_gl_context_activate (self->gst_gdk_context, TRUE);
-        gst_gl_sync_meta_wait (sync_meta, self->gst_gdk_context);
-        gst_gl_context_activate (self->gst_gdk_context, FALSE);
-      }
 
+      /* Note: using the gdk_context here is a (harmless) lie,
+       * since the texture really originates in the gst_context.
+       * But that is not a GdkGLContext. It is harmless, because
+       * we are never using the texture in the gdk_context, so we
+       * never make the (erroneous) decision to ignore the sync.
+       */
       builder = gdk_gl_texture_builder_new ();
       gdk_gl_texture_builder_set_context (builder, self->gdk_context);
       gdk_gl_texture_builder_set_id (builder, *(guint *) frame->data[0]);
       gdk_gl_texture_builder_set_width (builder, frame->info.width);
       gdk_gl_texture_builder_set_height (builder, frame->info.height);
+      gdk_gl_texture_builder_set_sync (builder, sync_meta ? sync_meta->data : NULL);
 
       texture = gdk_gl_texture_builder_build (builder,
                                               (GDestroyNotify) video_frame_free,