HIP RT enables AMD hardware ray tracing on RDNA2 and above, and falls back to a
to shader implementation for older graphics cards. It offers an average 25%
sample rendering rate improvement in Cycles benchmarks, on a W6800 card.
The ray tracing feature functions are accessed through HIP RT SDK, available on
GPUOpen. HIP RT traversal functionality is pre-compiled in bitcode format and
shipped with the SDK.
This is not yet enabled as there are issues to be resolved, but landing the
code now makes testing and further changes easier.
Known limitations:
* Not working yet with current public AMD drivers.
* Visual artifact in motion blur.
* One of the buffers allocated for traversal has a static size. Allocating it
dynamically would reduce memory usage.
* This is for Windows only currently, no Linux support.
Co-authored-by: Brecht Van Lommel <brecht@blender.org>
Ref #105538