From da0678617b20015045bb6896544c92f5a26fa10d Mon Sep 17 00:00:00 2001
From: Jonathan Moore Liles <j.liles@unix.net>
Date: Tue, 23 Jul 2013 18:00:31 -0700
Subject: [PATCH] Fl_Double_Window: Clear clipping region when backbuffer is
 invalidated.

---
 src/Fl_Double_Window.cxx | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Fl_Double_Window.cxx b/src/Fl_Double_Window.cxx
index 17969ee..e26b4ad 100644
--- a/src/Fl_Double_Window.cxx
+++ b/src/Fl_Double_Window.cxx
@@ -328,6 +328,8 @@ void Fl_Double_Window::flush(int eraseoverlay) {
     cairo_surface_t *cs = Fl::cairo_create_surface( myi->other_xid, w(), h() );
     myi->other_cc = cairo_create( cs );
     cairo_surface_destroy( cs );
+
+    if ( myi->region ) { cairo_region_destroy( myi->region ); myi->region = 0; }
   }
   
   fl_clip_region(myi->region);