From 79a7f8c729df447076bcc13d69d7306115dec611 Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Sat, 29 Oct 2005 10:04:35 +0000
Subject: [PATCH] Added catch for NULL return from glGetString( GL_VERSION );

---
 src/osg/Texture.cpp | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/osg/Texture.cpp b/src/osg/Texture.cpp
index deb471eea..63aade119 100644
--- a/src/osg/Texture.cpp
+++ b/src/osg/Texture.cpp
@@ -1323,7 +1323,15 @@ void Texture::Extensions::lowestCommonDenominator(const Extensions& rhs)
 
 void Texture::Extensions::setupGLExtensions(unsigned int contextID)
 {
-    float glVersion = atof( (const char *)glGetString( GL_VERSION ) );
+    const char* version = (const char*) glGetString( GL_VERSION );
+    if (!version)
+    {
+        osg::notify(osg::FATAL)<<"Error: In Texture::Extensions::setupGLExtensions(..) OpenGL version test failed, requires valid graphics context."<<std::endl;
+        return;
+    }
+    
+
+    float glVersion = atof( (const char *)version );
     const char* renderer = (const char*) glGetString(GL_RENDERER);
     std::string rendererString(renderer ? renderer : "");