Softimage's default mental ray renderer uses advanced rendering acceleration techniques such as scanline rendering algorithms for fast primary visible surface determination and BSP (binary space partitioning) algorithms for efficient rendering of ray tracing effects.
The BSP2 acceleration technique is the next generation BSP algorithm used by mental ray. It was developed, primarily, for the efficient rendering of scenes with large BSP trees and is required for rendering scenes with stand-ins (also known as mental ray assemblies). For scenes with assemblies, an independent tree is created for each one. This allows the complete removal of all structures associated with the BSP tree if an assembly is unloaded from memory.
Of particular note, BSP2 is also auto-configuring, which means that the algorithm itself determines the best maximum depth and maximum leaf size settings for the scene. Unlike the traditional BSP acceleration, there are no controlling options for the BSP2 acceleration and further manual tuning is not required to achieve performance and memory consumption improvements.
