From 6c47fc8322ab0378be6d19a76dccf3bc59a420ec Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lubo=C5=A1=20Lu=C5=88=C3=A1k?= <l.lunak@kde.org>
Date: Wed, 31 Oct 2007 16:28:59 +0000
Subject: [PATCH] Before destroying a current context, set some other current
 context (even none). Fixes crashes with Intel.

svn path=/trunk/KDE/kdebase/workspace/; revision=731410
---
 compositingprefs.cpp | 15 +++++----------
 scene_opengl.cpp     |  4 +++-
 2 files changed, 8 insertions(+), 11 deletions(-)

diff --git a/compositingprefs.cpp b/compositingprefs.cpp
index df9266ae7b..3584e10cae 100644
--- a/compositingprefs.cpp
+++ b/compositingprefs.cpp
@@ -76,9 +76,7 @@ void CompositingPrefs::detect()
     GLXDrawable olddrawable = glXGetCurrentDrawable();
     GLXDrawable oldreaddrawable;
     if( hasglx13 )
-    {
         oldreaddrawable = glXGetCurrentReadDrawable();
-    }
 
     if( createGLXContext() )
         {
@@ -87,17 +85,14 @@ void CompositingPrefs::detect()
 
         deleteGLXContext();
         }
-    if( oldcontext != NULL )
-    {
-        if( hasglx13 )
+    if( hasglx13 )
         {
-            glXMakeContextCurrent( display(), olddrawable, oldreaddrawable, oldcontext );
+        glXMakeContextCurrent( display(), olddrawable, oldreaddrawable, oldcontext );
         }
-        else
+    else
         {
-            glXMakeCurrent( display(), olddrawable, oldcontext );
+        glXMakeCurrent( display(), olddrawable, oldcontext );
         }
-    }
 #endif
     }
 
@@ -201,7 +196,7 @@ void CompositingPrefs::applyDriverSpecificOptions()
         mEnableCompositing = true;
         mStrictBinding = false;
         }
-    else if( mDriver == "intel")
+    else if( mDriver == "intel" )
         {
         kDebug() << "intel driver, disabling vsync, enabling direct";
         mEnableVSync = false;
diff --git a/scene_opengl.cpp b/scene_opengl.cpp
index f2d3d28c60..239fd26552 100644
--- a/scene_opengl.cpp
+++ b/scene_opengl.cpp
@@ -189,6 +189,7 @@ SceneOpenGL::~SceneOpenGL()
             glXDestroyPixmap( display(), last_pixmap );
         glXDestroyContext( display(), ctxdrawable );
         }
+    glXMakeCurrent( display(), None, NULL );
     glXDestroyContext( display(), ctxbuffer );
     checkGLError( "Cleanup" );
     }
@@ -297,10 +298,11 @@ bool SceneOpenGL::initRenderingContext()
             kDebug( 1212 ) << "Couldn't initialize rendering context";
             return false;
             }
+	glXMakeCurrent( display(), None, NULL );
         glXDestroyContext( display(), ctxbuffer );
         direct_rendering = false; // try again
         ctxbuffer = glXCreateNewContext( display(), fbcbuffer, GLX_RGBA_TYPE, NULL, GL_FALSE );
-        if( ctxbuffer == NULL || !glXMakeCurrent( display(), glxbuffer, ctxbuffer ))
+        if( ctxbuffer == NULL || !glXMakeCurrent( display(), glxbuffer, ctxbuffer ) || errs.error( true ))
             {
             kDebug( 1212 ) << "Couldn't initialize rendering context";
             return false;