[gtk+/wip/gdk-gl: 11/31] x11: Update GL viewport on ConfigureNotify

[Emmanuele Bassi <ebassi src gnome org>]

commit 686f9b46070cd8fd257bd367f2a1e0595ddc50dd
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Mon Aug 11 21:29:00 2014 +0100

    x11: Update GL viewport on ConfigureNotify
    
    On X11, by virtue of the asynchronous nature of the protocol, we have to
    wait until the ConfigureNotify event to resize the GL viewport. If the
    GdkWindow is a top-level one, then we'll get a GDK_CONFIGURE event, but
    if we're using a GDK_WINDOW_CHILD the event will be dropped on the
    floor.

 gdk/x11/gdkdisplay-x11.c |   24 ++++++++++++++++++++----
 1 files changed, 20 insertions(+), 4 deletions(-)
---
diff --git a/gdk/x11/gdkdisplay-x11.c b/gdk/x11/gdkdisplay-x11.c
index 1837347..f6ba01a 100644
--- a/gdk/x11/gdkdisplay-x11.c
+++ b/gdk/x11/gdkdisplay-x11.c
@@ -782,11 +782,27 @@ gdk_x11_display_translate_event (GdkEventTranslator *translator,
        }
 #endif
 
-    if (!window ||
-         xevent->xconfigure.event != xevent->xconfigure.window ||
-          GDK_WINDOW_TYPE (window) == GDK_WINDOW_CHILD ||
+      if (!window ||
+          xevent->xconfigure.event != xevent->xconfigure.window ||
           GDK_WINDOW_TYPE (window) == GDK_WINDOW_ROOT)
-       return_val = FALSE;
+        {
+          return_val = FALSE;
+        }
+      else if (GDK_WINDOW_TYPE (window) == GDK_WINDOW_CHILD)
+        {
+          /* on X11 we need to wait until a ConfigureNotify before
+           * updating the GL viewport, otherwise the GLX drawable
+           * and the X drawable will go out of sync.
+           */
+          if (gdk_window_has_gl_context (window))
+            {
+              GdkGLContext *context = gdk_window_get_gl_context (window);
+
+              gdk_gl_context_update (context);
+            }
+
+          return_val = FALSE;
+        }
       else
        {
          event->configure.type = GDK_CONFIGURE;