From 4cdcb009efbff8846ed93e640a260db1bef549fa Mon Sep 17 00:00:00 2001
From: Campbell Barton <ideasman42@gmail.com>
Date: Sep 28 2016 21:01:26 +0000
Subject: Fix/Workaround bug #591


We could check for the extensions but these OpenGL options are never used,
so no need to disable them.

---

diff --git a/toonz/sources/toonzlib/stagevisitor.cpp b/toonz/sources/toonzlib/stagevisitor.cpp
index f3746ab..dc256db 100644
--- a/toonz/sources/toonzlib/stagevisitor.cpp
+++ b/toonz/sources/toonzlib/stagevisitor.cpp
@@ -602,6 +602,9 @@ void RasterPainter::flushRasterImages() {
   glDisable(GL_DITHER);
   glDisable(GL_LOGIC_OP);
 
+/* disable, since these features are never enabled, and cause OpenGL to assert
+ * on systems that don't support them: see #591 */
+#if 0
 #ifdef GL_EXT_convolution
   glDisable(GL_CONVOLUTION_1D_EXT);
   glDisable(GL_CONVOLUTION_2D_EXT);
@@ -612,6 +615,7 @@ void RasterPainter::flushRasterImages() {
   glDisable(GL_HISTOGRAM_EXT);
   glDisable(GL_MINMAX_EXT);
 #endif
+#endif
 
 #ifdef GL_EXT_texture3D
   glDisable(GL_TEXTURE_3D_EXT);