Use a dedicated VBO for RigGeometry's vertices and normals

The VBO used by the source geometry's arrays may be unintentionally shared with other RigGeometries.

The vertices and normals are the only attributes that are modified at all, so using a dedicated VBO for these should improve performance further.

components/sceneutil/riggeometry.cpp

@@ -71,8 +71,7 @@ RigGeometry::RigGeometry()
     setCullCallback(new UpdateRigGeometry);
     setUpdateCallback(new UpdateRigBounds);
     setSupportsDisplayList(false);
-    //setUseVertexBufferObjects(true);
-    //getOrCreateVertexBufferObject()->setUsage(GL_DYNAMIC_DRAW_ARB);
+    setUseVertexBufferObjects(true);
     setComputeBoundingBoxCallback(new DummyComputeBoundCallback);
 }
 
@@ -121,8 +120,23 @@ void RigGeometry::setSourceGeometry(osg::ref_ptr<osg::Geometry> sourceGeometry)
             setVertexAttribArray(vi,array);
     }
 
-    setVertexArray(dynamic_cast<osg::Array*>(from.getVertexArray()->clone(osg::CopyOp::DEEP_COPY_ALL)));
-    setNormalArray(dynamic_cast<osg::Array*>(from.getNormalArray()->clone(osg::CopyOp::DEEP_COPY_ALL)), osg::Array::BIND_PER_VERTEX);
+
+    osg::ref_ptr<osg::VertexBufferObject> vbo (new osg::VertexBufferObject);
+    vbo->setUsage(GL_DYNAMIC_DRAW_ARB);
+
+    osg::ref_ptr<osg::Array> vertexArray = osg::clone(from.getVertexArray(), osg::CopyOp::DEEP_COPY_ALL);
+    if (vertexArray)
+    {
+        vertexArray->setVertexBufferObject(vbo);
+        setVertexArray(vertexArray);
+    }
+
+    osg::ref_ptr<osg::Array> normalArray = osg::clone(from.getNormalArray(), osg::CopyOp::DEEP_COPY_ALL);
+    if (normalArray)
+    {
+        normalArray->setVertexBufferObject(vbo);
+        setNormalArray(normalArray, osg::Array::BIND_PER_VERTEX);
+    }
 }
 
 bool RigGeometry::initFromParentSkeleton(osg::NodeVisitor* nv)