Hans-Kristian Arntzen has opened the initial pull request for enabling ray-tracing extensions with VKD3D-Proton.
He noted in the PR , " Don't expose any features to app yet, but allow overriding [feature level] to 12.2 for local testing while bringing up DXR. "
Seeing DirectX Ray-Tracing (DXR) working atop Vulkan ray-tracing will certainly be exciting considering the current lack of native Linux games making use of Vulkan ray-tracing.
Vulkan 1.2.162 released back in November formalized the API's ray-tracing support following the preliminary specification last March . Vulkan ray-tracing was engineered with DXR and NVIDIA's existing ray-tracing vendor extension in mind so the portability of DXR atop Vulkan shouldn't be too much of a burden.
It will be quite fun to see how quickly DirectX Ray-Tracing comes together for VKD3D-Proton and in turn appearing within Steam Play. Among the high profile games currently supporting DXR include Cyberpunk 2077, Wolfenstein: Youngblood, Minecraft, Metro Exodus, Fortnite, Battlefield 5, and others. Obviously as the year progresses we are likely to see many more DXR titles.