From 0764e36c3d5eaa27331342dd7e3edcf13ff3b11f Mon Sep 17 00:00:00 2001
From: san <san@opencascade.com>
Date: Wed, 6 Jun 2018 19:58:10 +0300
Subject: [PATCH] 0029844: Volume Rendering - NVIDIA graphic driver timeout
 errors with callback enabled

An attempt to resolve CPU-GPU synchronization issues using glFinish()
---
 src/OpenGl/OpenGl_Context.cxx     | 2 +-
 src/OpenGl/OpenGl_View_Redraw.cxx | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/OpenGl/OpenGl_Context.cxx b/src/OpenGl/OpenGl_Context.cxx
index 18cbea056d..8e0beecc4b 100644
--- a/src/OpenGl/OpenGl_Context.cxx
+++ b/src/OpenGl/OpenGl_Context.cxx
@@ -671,7 +671,7 @@ void OpenGl_Context::SwapBuffers()
   if ((HDC )myWindowDC != NULL)
   {
     ::SwapBuffers ((HDC )myWindowDC);
-    glFlush();
+    glFinish();
   }
 #else
   if ((Display* )myDisplay != NULL)
diff --git a/src/OpenGl/OpenGl_View_Redraw.cxx b/src/OpenGl/OpenGl_View_Redraw.cxx
index d499839e4d..a25ebf2c08 100644
--- a/src/OpenGl/OpenGl_View_Redraw.cxx
+++ b/src/OpenGl/OpenGl_View_Redraw.cxx
@@ -561,7 +561,7 @@ void OpenGl_View::Redraw()
   }
   else
   {
-    aCtx->core11fwd->glFlush();
+    aCtx->core11fwd->glFinish();
   }
 
   // reset render mode state
@@ -731,7 +731,7 @@ void OpenGl_View::RedrawImmediate()
   }
   else
   {
-    aCtx->core11fwd->glFlush();
+    aCtx->core11fwd->glFinish();
   }
   aCtx->FrameStats()->FrameEnd (myWorkspace);
 
-- 
2.39.5