From 22c4e4d240133e45230c7ef5c4dbb209fb75e4f8 Mon Sep 17 00:00:00 2001
From: Maciej Suminski <maciej.suminski@cern.ch>
Date: Tue, 3 May 2016 16:39:58 +0200
Subject: [PATCH] Set OpenGL context only when the parent window is visible.

---
 common/gal/opengl/opengl_gal.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/common/gal/opengl/opengl_gal.cpp b/common/gal/opengl/opengl_gal.cpp
index c498535eb8..c3ee4ac881 100644
--- a/common/gal/opengl/opengl_gal.cpp
+++ b/common/gal/opengl/opengl_gal.cpp
@@ -302,7 +302,9 @@ void OPENGL_GAL::EndDrawing()
 
 void OPENGL_GAL::BeginUpdate()
 {
-    SetCurrent( *OPENGL_GAL::glContext );
+    if( IsShownOnScreen() )
+        SetCurrent( *OPENGL_GAL::glContext );
+
     cachedManager.Map();
 }