We describe OpenGL Multipipe SDK (MPK), a toolkit for scalable parallel rendering based on OpenGL. MPK provides a uniform application programming interface (API) to manage scalable graphics applications across many different graphics subsystems. MPKbased applications run seamlessly from single-processor, singlepipe desktop systems to large multi-processor, multipipe scalable graphics systems. The application is oblivious of the system con- figuration, which can be specified through a configuration file at run time.

To scale application performance, MPK uses a decomposition system that supports different modes for task partitioning and implements optimized GPU-based composition algorithms. MPK also provides a customizable image composition interface, which can be used to apply post-processing algorithms on raw pixel data obtained from executing sub-tasks on multiple graphics pipes in parallel. This can be used to implement parallel versions of any GPUbased algorithm, not necessarily used for rendering.

In this paper, we motivate the need for a scalable graphics API and discuss the architecture of MPK. We present MPK's graphics configuration interface, introduce the notion of compound-based decomposition schemes and describe our implementation. We present some results from our work on a couple of target system architectures and conclude with future directions of research in this area.