What engine are these screenshots from?

I was looking at the Quaketastic directories today and I found this folder in the screenshots directory called “200_height_tests”. It appears to be screenshots of an engine using a toggle to run all 2d assets with non-square pixels, akin to running in 320x200 or 640x400 resolutions in DOS or WinQuake. But what engine is this? I’ve been interested in the idea of an engine that supports this feature, but I never actually found one in the wild that had this feature. Does anyone know where I could find this? Maybe it’s on the Quaddicted archive? Any leads would be helpful.

Link to images: http://www.quaketastic.com/?dir=files/screen_shots/200_Height_Tests

Hmm, it’s a engine with texture filtering so most probably not a software renderer. I’d check FTEQW, MarkV, QSS, Quakeforge for a start.

Took a look through old versions of all the engines you mentioned on the Quaddicted archive, none of them have the feature. Based on the screenshots, it reminds me of early Mark V just with that extra toggle…