Nvidia releases VKRay Vulkan ray tracing extension

Nvidia has announced the release of an experimental extension to the low-level Vulkan graphics application programming interface (API) which allows real-time ray tracing via its Turing RT core hardware, allowing accelerated ray tracing via GeForce RTX graphics cards to work on non-Windows systems.

When Nvidia launched its Turing graphics architecture, first in the professional-grade Quadro RTX family and later in the consumer-grade GeForce RTX family, it made much of the dedicated RT cores which allow for real-time ray tracing. With the cards now out, though, software support is still thin on the ground: Microsoft's DirectX Raytracing (DXR), which lets developers actually use the RT cores for ray tracing in games and other applications, is only available to the general public as part of the still-on-hold Windows 10 October 2018 Update.

Acutely aware that hardware needs software, Nvidia has released a new driver revision which contains the first support for the RT cores outside DirectX Raytracing: an experimental vendor extension for the Khronos Group's Vulkan API.

'Many developers want to embrace a more open approach using Vulkan, the low-level API supported by the Khronos Group,' explains Nvidia's Nuno Subtil in a blog post. 'Vulkan enables developers to target many different platforms, including Windows and Linux, allowing for broader distribution of 3D-accelerated applications. Nvidia's 411.63 driver release now enables an experimental Vulkan extension that exposes Nvidia's RTX technology for real-time ray tracing through the Vulkan API. This extension, called "VK_NVX_raytracing," is a developer preview of our upcoming vendor extension for ray tracing on Vulkan. The extension targets developers who want to familiarise themselves with API concepts and start testing the functionality.'

For those eager to see wider support for Nvidia's RTX cards, there's a catch: The current release is experimental and non yet finalised, though Subtil expects that only 'minor changes' will be made before it becomes an official extension under the name VKRay. It may not be how Vulkan ray tracing ends up working, however: 'Nvidia remains committed to working within Khronos on multi-vendor standardisation efforts for ray tracing functionality in Vulkan,' Subtil explains, 'and we've offered our extension as one starting point for discussion.'

Nvidia has not yet indicated a timeline for VKRay's finalisation.