Quake II RTX released back in 2019, with NVIDIA using it to show off more ray tracing effects for their RTX GPUs but now they're done with it. It's still free on Steam and the project behind it is open source, but NVIDIA aren't doing any more with it now.
Noted on the GitHub page is a message that it has been discontinued, and the GitHub repository has been archived. They did one small final release version 1.8.1 with a few fixes but that's it now.

More about it: "Quake II RTX builds on the work of Christoph Schied and the team at the Karlsruhe Institute of Technology, who added ray tracing to Quake II to create Q2VKPT (in turn building upon the Q2PRO code base). NVIDIA has introduced new path-traced visual effects, has improved texturing, and has made dozens of other changes and improvements, resulting in an experience that rivals games created today, and pushes your RTX hardware to the limit."




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