Separate projects. Niels Leenheer who made CSS Doom has seen Agustin Capeletto's CSS Quake.
replyAnd I think both have seen these much older handcrafted css3d engines
reply- https://pantel.is/projects/css3d/
- https://keithclark.co.uk/labs/css-fps/ (the original)
but quake and doom took it to the next level :)
The source appears to be <https://github.com/LayoutitStudio/cssQuake>
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