From a8d5d7cdba8943e28b2d90f10c93c305ea74f008 Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Tue, 10 Jun 2014 00:38:38 +0000
Subject: [PATCH] Don't assert in wxOSX if a shaped window doesn't define a
 valid shape.

A window with wxFRAME_SHAPED style can still not defined any valid shape
actually, in which case wxFRAME_SHAPED should be just ignored.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76681 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
---
 src/osx/cocoa/window.mm | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/src/osx/cocoa/window.mm b/src/osx/cocoa/window.mm
index e5d1183cb5..16bb5c4510 100644
--- a/src/osx/cocoa/window.mm
+++ b/src/osx/cocoa/window.mm
@@ -1549,20 +1549,23 @@ void wxWidgetCocoaImpl::drawRect(void* rect, WXWidget slf, void *WXUNUSED(_cmd))
     wxRegion clearRgn;
     if ( tlwParent->GetWindowStyle() & wxFRAME_SHAPED )
     {
-        if ( isTopLevel )
-            clearRgn = updateRgn;
-
-        int xoffset = 0, yoffset = 0;
         wxRegion rgn = tlwParent->GetShape();
-        wxpeer->MacRootWindowToWindow( &xoffset, &yoffset );
-        rgn.Offset( xoffset, yoffset );
-        updateRgn.Intersect(rgn);
-
-        if ( isTopLevel )
+        if ( rgn.IsOk() )
         {
-            // Exclude the window shape from the region to be cleared below.
-            rgn.Xor(wxpeer->GetSize());
-            clearRgn.Intersect(rgn);
+            if ( isTopLevel )
+                clearRgn = updateRgn;
+
+            int xoffset = 0, yoffset = 0;
+            wxpeer->MacRootWindowToWindow( &xoffset, &yoffset );
+            rgn.Offset( xoffset, yoffset );
+            updateRgn.Intersect(rgn);
+
+            if ( isTopLevel )
+            {
+                // Exclude the window shape from the region to be cleared below.
+                rgn.Xor(wxpeer->GetSize());
+                clearRgn.Intersect(rgn);
+            }
         }
     }