Ensure immediate canvas update inside GUI windows.

Ensure canvas displayed inside GUI windows are updated in the same
frame as the according window is made visible. This prevents
showing previous contents for the first frame.

diff --git a/src/Canvas/window.cxx b/src/Canvas/window.cxx
index d0d72f509077262f9346908178e587b8b6ed2dc0..80ef5677e9e34f5f64c04dd1a1e3a8f68ad4e3ba 100644 (file)
--- a/src/Canvas/window.cxx
+++ b/src/Canvas/window.cxx
@@ -79,6 +79,17 @@ namespace canvas
         _capture_events = node->getBoolValue();
       else
         handled = false;
+
+      // Ensure canvas is redrawn before the window is displayed after it has
+      // been hidden. We can't rely on the cull callback as it gets called too
+      // late (GUI camera is attached as POST_RENDER whereas canvas contents are
+      // rendered during PRE_RENDER).
+      if( node->getNameString() == "visible" && node->getBoolValue() )
+      {
+        simgear::canvas::CanvasPtr canvas = getCanvas().lock();
+        if( canvas )
+          canvas->enableRendering();
+      }
     }
 
     if( !handled )