From 0b5c20af8d8def4cc33d35e11c4658b66aa5485c Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Mon, 26 Aug 2002 12:34:42 +0000
Subject: [PATCH] Made the sort callback's sort method pure virtual.

---
 include/osgUtil/RenderBin | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/osgUtil/RenderBin b/include/osgUtil/RenderBin
index c0f3fd85e..de70983a5 100644
--- a/include/osgUtil/RenderBin
+++ b/include/osgUtil/RenderBin
@@ -72,7 +72,7 @@ class OSGUTIL_EXPORT RenderBin : public osg::Object
         
         struct SortCallback : public osg::Referenced    
         {
-            virtual void sort(RenderBin*) {};
+            virtual void sort(RenderBin*) = 0;
         };
 
         void setSortLocalCallback(SortCallback* sortCallback) { _sortLocalCallback = sortCallback; }