public override void SetZoneGeometry( string filename, PCZSceneNode parentNode )
{
String entityName, nodeName;
entityName = this.Name + "_entity";
nodeName = this.Name + "_Node";
Entity ent = mPCZSM.CreateEntity( entityName, filename );
// create a node for the entity
PCZSceneNode node;
node = (PCZSceneNode)( parentNode.CreateChildSceneNode( nodeName, Vector3.Zero, Quaternion.Identity ) );
// attach the entity to the node
node.AttachObject( ent );
// set the node as the enclosure node
SetEnclosureNode( node );
}