The steam build is based off this: https://github.com/NVIDIA/Q2RTX
An excerpt from that link which is relevant to the interest of DDAY:
The current DDAY bundle is wrapped around Q2PRO, so I SUSPECT getting this ported to the Q2RTX engine should be just a matter of copypasta, and editing a few things here and there.Quake II RTX is NVIDIA's attempt at implementing a fully functional version of Id Software's 1997 hit game Quake II with RTX path-traced global illumination.
Quake II RTX builds upon the Q2VKPT branch of the Quake II open source engine. Q2VKPT was created by former NVIDIA intern Christoph Schied, a Ph.D. student at the Karlsruhe Institute of Technology in Germany.
Q2VKPT, in turn, builds upon Q2PRO, which is a modernized version of the Quake II engine. Consequently, many of the settings and console variables that work for Q2PRO also work for Quake II RTX. The client and server manuals are particularly useful.
JUST as a matter of curiosity, I took a quick pass at dumping the dday files into my ~/.local/share/Steam/steamapps/common/Quake II RTX/ path, and tweaked a few things to see if I could overcome some crashes.
(Open these in new tab if you can't read the things)
I'm sure that's the end of the line of a drag-and-drop attempt, but compiling dday source to use Q2RTX shouldn't be a massive task, unless someone here knows better.
