With OptiX 3.5 we stepped up the quality of our documentation. It’s more detailed, more accurate, and more browsable, since we use Doxygen for all of the reference manual. Also, OptiX is part of Nvidia’s new GameWorks program. As such, our documentation is hosted online at http://docs.nvidia.com. We’ll continue to improve it, but we’re excited about the progress we’ve already made.
The reference manual main page is here: http://docs.nvidia.com/gameworks/content/gameworkslibrary/optix/optixapireference/_opti_x_chapters.html