Is the Restir GI Method Patented?

Are the Restir and Restir GI methods patented by Nvidia? Are they able to be used in my own application, or do I have to pay some sort of fee? I know I could use RTXDI, but that does not allow as much compatibility as I want, I want to create a custom solution for my game engine in Vulkan.

As far as I know, the answer is No. But you should read the licensing terms for all the libraries’ licensing terms you use in your game or app carefully, and go from there. Excepting official answers in this forum = crickets.