[gtk: 1/3] wayland/glcontext: Sync surface state before swapping buffers

[Matthias Clasen <matthiasc src gnome org>]

commit 1d5d46ff29c7e5c012bf7dd571304cc54fb95bed
Author: Jonas Ådahl <jadahl gmail com>
Date:   Wed Mar 21 14:01:58 2018 +0800

    wayland/glcontext: Sync surface state before swapping buffers
    
    A side effect of eglSwapBuffers* is the EGL implementation calling
    wl_surface_commit() on the corresponding Wayland surface. Thus, before
    swapping buffers, we must synchronize the surface state (e.g. opaque
    region, window geometry, etc) that changed since the last buffer swap.
    Prior to this commit, this was done after eglSwapBuffers*, causing the
    surface state to always correspond to the previous buffer state. As of
    this commit this is now done before swapping the buffers, thus before
    wl_surface_commit().

 gdk/wayland/gdkglcontext-wayland.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gdk/wayland/gdkglcontext-wayland.c b/gdk/wayland/gdkglcontext-wayland.c
index 1e6f2ca28a..700baa02d6 100644
--- a/gdk/wayland/gdkglcontext-wayland.c
+++ b/gdk/wayland/gdkglcontext-wayland.c
@@ -223,6 +223,8 @@ gdk_wayland_gl_context_end_frame (GdkDrawContext *draw_context,
   egl_surface = gdk_wayland_surface_get_egl_surface (surface->impl_surface,
                                                     context_wayland->egl_config);
 
+  gdk_wayland_surface_sync (surface);
+
   if (display_wayland->have_egl_swap_buffers_with_damage && damage != NULL)
     {
       int i, j, n_rects = cairo_region_num_rectangles (damage);
@@ -243,8 +245,6 @@ gdk_wayland_gl_context_end_frame (GdkDrawContext *draw_context,
     }
   else
     eglSwapBuffers (display_wayland->egl_display, egl_surface);
-
-  gdk_wayland_surface_sync (surface);
 }
 
 static void