A Generalized Scene Graph

Scene graphs are fundamental data structures for hierarchical scene modeling. The generalized scene graph overcomes various limitations of current scene graph architectures such as support for different 3D rendering systems, integration of multi-pass rendering, and declarative modeling of scenes. The main idea is to separate scene specification from scene evaluation. To specify scenes, scene graph nodes are arranged and equipped with rendering objects, e.g., shapes, attributes, and algorithms. To evaluate scenes, the contents of scene graphs nodes, the rendering objects, are evaluated by rendering engines, which use the algorithm objects to interpret shapes and attributes. Using generalized scene graphs, most real-time rendering techniques for OpenGL and several 3D rendering systems can be integrated in a single scene representation without loosing control over or limiting individual strengths of rendering systems.