Modder Cheelo is taking Doom's classic 2D sprites and translating them into 3D voxel versions for a new take on the classic FPS' iconic designs.
Even beyond its contributions to first person shooters, Doom was essential to the development of 3D game design more broadly. The game's enemies and objects, however, consist of 2D sprites that rotate to face the player, with id's later shooter Quake bringing the now-standard 3D models into the picture.
The idea of populating Doom with full 3D models instead of a 2.5D compromise has had purchase in the community for a long time, but traditional 3D modelling could run the risk of entering “Nintendo, hire this man” territory, overpowering the charming original designs with something of higher fidelity, but not necessarily quality. Voxel art—a style of 3D modelling that can resemble pixel art—provides a route for bringing Doom's critters to 3D without sacrificing id's distinctive art style.
Multiple projects to bring voxel models to Doom seem to have emerged out of the Doomworld forums in the 2000s and early 2010s, but nothing came of them and users theorize that the OpenGL rendering used by Doom's various source ports was uniquely unsuited to render voxels, dooming any further efforts.
Despite that history, Cheelo has been steadily posting updates of this new Doom Voxel project to YouTube and Twitter, and most recently demonstrated the mod working on E1M5. The voxel objects and enemies have an uncanny effect where you could mistake them for 2D sprites from far away, but upon closer inspection have a depth and presence we've never seen from these classic designs.
Cheelo has previously given the voxel treatment to assets in Monolith's Blood, and you can follow progress on Doom Voxel via Cheelo's Twitter and YouTube channels. Cheelo also has a Ko-Fi page to support the artist, with a stated goal of acquiring an RTX-ready system to help test and implement Doom Voxel with sultim-t's Ray Tracing mod for Doom.