Who is they? NVIDIA provides multiple APIs which are accessible through various APIs or natively the point of the hardware is to provide specific interfaces and

Who is they? NVIDIA provides multiple APIs which are accessible through various APIs or natively the point of the hardware is to provide specific interfaces and data types which make RT faster these are not limited to a specific graphical API. You can use it trough Optix which is proprietary low level C++ API based on CUDA, you can use it with Vulkan or DX12 DXR the levels of abstraction are dependent on what API/interface you’ll be using. On top of that NVIDIA provides ready to use hybrid ray tracing libraries which are built on top of Microsoft DXR currently with Vulkan coming within the next 2-3 months. But you don’t have to use their hybrid path tracing or denoiser you can develop it completely on your own.