From 10b6309f791f837f9033e186aac35cf9c0805f42 Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Mon, 27 Oct 2008 16:06:24 +0000
Subject: [PATCH] From Chris Denham, fixed support of in scene graph
 osg::Camera's with ReferenceFrame of RELATIVE_RF.

---
 src/osgUtil/IntersectionVisitor.cpp | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/src/osgUtil/IntersectionVisitor.cpp b/src/osgUtil/IntersectionVisitor.cpp
index 575c957e6..c6486e2df 100644
--- a/src/osgUtil/IntersectionVisitor.cpp
+++ b/src/osgUtil/IntersectionVisitor.cpp
@@ -438,9 +438,30 @@ void IntersectionVisitor::apply(osg::Camera& camera)
     
     // osg::notify(osg::NOTICE)<<"inside apply(Camera&)"<<std::endl;
 
+    osg::RefMatrix* projection = NULL;
+    osg::RefMatrix* view = NULL;
+
+    if (camera.getReferenceFrame()==osg::Transform::RELATIVE_RF && getProjectionMatrix() && getViewMatrix())
+    {
+        if (camera.getTransformOrder()==osg::Camera::POST_MULTIPLY)
+        {
+            projection = new osg::RefMatrix(*getProjectionMatrix()*camera.getProjectionMatrix());
+            view = new osg::RefMatrix(*getViewMatrix()*camera.getViewMatrix());
+        }
+        else // pre multiply 
+        {
+            projection = new osg::RefMatrix(camera.getProjectionMatrix()*(*getProjectionMatrix()));
+            view = new osg::RefMatrix(camera.getViewMatrix()*(*getViewMatrix()));
+        }
+    } else {
+        // an absolute reference frame
+        projection = new osg::RefMatrix(camera.getProjectionMatrix());
+        view = new osg::RefMatrix(camera.getViewMatrix());
+    }
+ 
     if (camera.getViewport()) pushWindowMatrix( camera.getViewport() );
-    pushProjectionMatrix( new osg::RefMatrix(camera.getProjectionMatrix()) );
-    pushViewMatrix( new osg::RefMatrix(camera.getViewMatrix()) );
+    pushProjectionMatrix(projection);
+    pushViewMatrix(view);
     pushModelMatrix( new osg::RefMatrix() );
 
     // now push an new intersector clone transform to the new local coordinates