Entity The Entity class provides an abstract base class for all scene graph objects that are considered having a "presence" in the scene, in the sense that it can be considered an actual object with a position and a size (even if infinite or idealised), rather than a grouping.
 Mesh Mesh is an instance of a Geometry, augmenting it with a presence in the scene graph, a material, and an animation state.
 Sprite3D Sprite3D is a 3D billboard, a renderable rectangular area that is always aligned with the projection plane.