Two provisional extensions for mobile app development are poised to revolutionize the world of ray-tracing in Vulkan, making it possible for developers to create device-independent, cross-platform code. The new Vulkan ray-tracing API is a significant step forward, offering unparalleled flexibility and power.
The journey towards this milestone began with two current provisional extensions, VK_KHR_ray_tracing and SPV_KHR_ray_tracing, which are now on the cusp of being finalized as part of the core Vulkan API. Intel, a leading GPU vendor, has taken the lead in driving this innovation forward. Jason Ekstrand, an Intel-employed developer, delivered a comprehensive overview of the upcoming Vulkan Ray-Tracing API at the X.Org Developers Conference 2020.
What is Ray-Tracing?
In simple terms, ray-tracing is about tracing light rays to create stunning visuals. It's a new 3D rendering API that allows developers to craft immersive experiences with unprecedented realism. The current state of Vulkan only offers vendor-specific extensions from Nvidia, but this is set to change with the introduction of two new, vendor-neutral extensions.
The new Vulkan ray-tracing API comes in two parts: acceleration structures and six new shader stages. Acceleration structures hold all the geometry for a scene, while shader stages dispatch rays, define procedural geometry, and handle hits and misses. This marks a significant departure from the existing rendering path, which will now be replaced by a more complex, compute-like process.
The Future of Mobile App Development
The new Vulkan ray-tracing API is designed to be vastly different from the current non-ray-tracing rendering path. Everything in a single scene needs to be dumped into a large acceleration structure before any ray-tracing steps can be taken. This is unlike the regular forward rendering path, where each part of a scene can simply be rendered and discarded.
Intel-employed Mesa developer Jason Ekstrand delivered a 46-minute presentation on the new Vulkan ray-tracing API at the X.Org Developers Conference 2020, providing insight into its features, functionality, and practical applications. The full video is available below:
Copyright X.Org Developers Conference 2020. Licensed under Creative Commons CC-BY.
Ekstrand did not provide details on Intel's plans for ray-tracing or indicate what graphics hardware will be required to use the new API. However, he did confirm that the provisional extensions are currently not available in the ANV and RADV Vulkan drivers in Mesa git.