Hierarchical Parallelism in a Scene Graph

We present a scene graph architecture that features and supports parallelism at multiple levels. Hierarchical parallelism increases overall end-to-end throughput at each stage of the graphics pipeline, from database cre- ation through rendering. A thread-safe scene graph is the fundamental data structure in our design model. Multiple rendering engines may simultaneously read from the scene graph, and multiple application threads may simultaneously write to the scene graph. Each ren- dering engine in this architecture is itself a multistage, multithreaded software component that draws to sepa- rate hardware-accelerated displays. We describe the data structures and access methods that provide thread safety amongst multiple rendering engines and outline how an individual multistage, multithreaded rendering engine uses this infrastructure effectively.