From 8bbbea127410999a90fab1dd63c26873759e8835 Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Tue, 11 Feb 2014 18:18:48 +0000
Subject: [PATCH] Fixed handling of assignment of User Object's that replace
 existing Object with the specified propertyName.

---
 include/osgDB/PropertyInterface | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/include/osgDB/PropertyInterface b/include/osgDB/PropertyInterface
index 3d5548dac..d2c7e8441 100644
--- a/include/osgDB/PropertyInterface
+++ b/include/osgDB/PropertyInterface
@@ -272,11 +272,24 @@ inline bool PropertyInterface::setProperty(osg::Object* object, const std::strin
     if (copyPropertyObjectToObject(object, propertyName, &value, sizeof(ObjectPtr), getTypeEnum<ObjectPtr>())) return true;
     else
     {
-        OSG_NOTICE<<"PropertyInterface::setProperty("<<propertyName<<", "<<value->className()<<") Adding object to UserDataContainer"<<std::endl;
         // fallback to using user data to store property data
         osg::UserDataContainer* udc = object->getOrCreateUserDataContainer();
-        value->setName(propertyName);
-        udc->addUserObject(value);
+        unsigned int objectIndex = udc->getUserObjectIndex(propertyName);
+        if (objectIndex < udc->getNumUserObjects())
+        {
+            const osg::Object* outgoingObject = udc->getUserObject(objectIndex);
+            if (outgoingObject==value) return true;
+
+            OSG_NOTICE<<"PropertyInterface::setProperty("<<propertyName<<", "<<value->className()<<") replace object on UserDataContainer"<<std::endl;
+            value->setName(propertyName);
+            udc->setUserObject(objectIndex, value);
+        }
+        else
+        {
+            OSG_NOTICE<<"PropertyInterface::setProperty("<<propertyName<<", "<<value->className()<<") Adding object to UserDataContainer"<<std::endl;
+            value->setName(propertyName);
+            udc->addUserObject(value);
+        }
         return true;
     }
 }