Jun 19, 2012 at 7:49 PM
Edited Jun 19, 2012 at 7:50 PM

Another scenario supported by the original D3DX9 library is Precomputed Radiance Transfer (PRT) and the associated simulator. These were not carried forward to newer D3DX editions and continue to only be available the legacy DirectX SDK's D3DX9 library. The shader-side use of PRT is reasonably easly to port to DirectX 11, but the offline building of the Spherical Harmonics (SH) data is not.

I have as a backlog item to rewrite the original SH math functions in D3DX9 using DirectXMath and release it on my blog, but that is only a small part of the PRT story.

For anyone interested in the details of the algorithms embodied in the legacy D3DX9 library, here are the original papers

Peter-Pike Sloan et al, "Local, Deformable Precomputed Radiance Transfer", ACM SIGGRAPH 2005 Proceedings

Peter-Pike Sloan et al., "Precomputed Radiance Transfer for Real-Time Rendering in Dynamic, Low-Frequency Lighting Environments" ACM SIGGRAPH 2002

Aug 25, 2012 at 7:36 PM

Note that the SH math and the cubemap projection functions are now available at <>