The Model and ModelPart classes deal with the definition of the geometry used by discrete movable objects. Entities are actual instances of objects based on this geometry in the world. Therefore there is usually a single set Model for a car, but there may be multiple entities based on it in the world. Entities are able to override aspects of the Model it is defined by, such as changing material properties per instance (so you can have many cars using the same geometry but different textures for example). Because a Model is split into a list of ModelPart objects for this purpose, the Entity class is a grouping class (much like the Model class) and much of the detail regarding individual changes is kept in the ActorPart class. There is a 1:1 relationship between ActorPart instances and the ModelPart instances associated with the Model the Entity is based on.

Entity and ActorPart classes are never created directly. Use [!:SceneGraph.CreateEntity] (passing a prototype name) to create one.

Entities are included in the scene by using [!:SceneObject.AddChild] to associate them with a scene node.