From e2240d3a56d3fdc178294701037fd8bbc160495b 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 2585bf66c1..8ca8f9974b 100644
--- a/src/OpenGl/OpenGl_Context.cxx
+++ b/src/OpenGl/OpenGl_Context.cxx
@@ -567,7 +567,7 @@ 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 7835b4f3a1..79f6e136ed 100644
--- a/src/OpenGl/OpenGl_View_Redraw.cxx
+++ b/src/OpenGl/OpenGl_View_Redraw.cxx
@@ -362,7 +362,7 @@ void OpenGl_View::Redraw()
   }
   else
   {
-    aCtx->core11fwd->glFlush();
+    aCtx->core11fwd->glFinish();
   }
 
   // reset render mode state
@@ -507,7 +507,7 @@ void OpenGl_View::RedrawImmediate()
   }
   else
   {
-    aCtx->core11fwd->glFlush();
+    aCtx->core11fwd->glFinish();
   }
 
   myWasRedrawnGL = Standard_True;
-- 
2.39.5