This change brings the following improvements on the user level
- Support of GPUs with gfx12 architecture
- New HIP-RT library which in addition to the gfx12 support brings
various bug-fixes.
The known limitation of gfx12 is that OpenImageDenoiser does not yet
support this GPU architecture. This means that while Cycles will use the
full advantage of the gfx12 (including hardware accelerated ray-tracing),
denoising will only be possible on CPU, or secondary gfx11 or below GPU.
This is something that requires a change in OIDN and it is to late to do
it for Blender 4.4, but it is something to look forward for Blender 4.5.
The gfx12 changes for the pre-compiled kernels is rather trivial,
so it comes together (in the same PR) as the bigger HIP-RT change.
On the development side this change brings the following improvements:
- One step compile and link (much simpler CMake rules)
- Embedding BVH binaries in hiprt dll (which makes it easier to package
and load, without relying on special path configuration)
Co-authored-by: Sahar Kashi <sahar.kashi@amd.com>
Co-authored-by: Sergey Sharybin <sergey@blender.org>
Co-authored-by: Brecht Van Lommel <brecht@blender.org>
Pull Request: https://projects.blender.org/blender/blender/pulls/133129
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
