The dhewm3 engine, which is one of the open-source forks of the id Tech 4 engine similar to ioDoom3, is now working on Wayland.
The main developer behind the "dhewm3" Doom 3 engine open-source project shared over the night within the Phoronix Forums that he has been playing around with Wayland. He ended up making improvements to the SDL 2.0 Wayland video driver and now he has his open-source engine with the Doom 3 game assets working atop Wayland/Weston!