Intel Begins Their Open-Source Driver Support For Vulkan Ray-Tracing With Xe HPG
Jason Ekstrand as the lead developer originally on the Intel ANV driver has posted today the initial ray-tracing code for ANV in order to support VK_KHR_ray_tracing for their forthcoming hardware. Today is the first time Intel has approved of this open-source code being published and more is on the way. The code today isn't enough for Vulkan ray-tracing but more is on the way and based against the latest internal Khronos ray-tracing specification. At the moment they are not focusing on the former NVIDIA-specific ray-tracing extension but may handle it in the future if game vendors continue targeting it rather than the forthcoming finalized KHR version.
There are the initial core ray-tracing bits on the compiler side now out for review plus a number of support patches needed for their implementation.
Among other big ticket items still to come in the near-term includes extending the ANV driver to support compiling and dispatching OpenCL kernels, new SPIR-V capabilities, and generic pointer support. Also needed is the actual support for compiling ray-tracing pipelines, managing acceleration structures, dispatching rays, and the platform support. The actual exposing of the support won't come until after The Khronos Group has firmed up their VK_KHR_ray_tracing extension.
Some of this Intel-specific Vulkan ray-tracing code may prove useful to Mesa's Radeon Vulkan "RADV" driver as well. Intel engineers have been testing their latest ray-tracing support with ANV internally on Xe HPG.
The initial Intel compiler patches for their ray-tracing handling can be found via this merge request. The compiler patches in their current form is just under five thousand lines of code while the previous NIR/SPIR-V patches are another six hundred lines and as said a lot more code is forthcoming ahead of the Intel Xe HPG hardware debut in 2021.