Brahma is a 3D game engine with a rather retrofuturistic design, intended for small studios and solo developers. It's being written from scratch in C++ using standard Windows API and no third-party libraries. This technology introduces an entirely new class of low-latency real-time engines that make special timing requirements, treating frames as video fields with a target time budget of 2-4 ms each, down from 16-33 ms frame budgets normally seen in game engines. It evolves in a different way than other modern engines, rejecting conventional BSP, Z-buffer, floating-point coordinates, and most of the lame screen-space effects in favor of innovative and efficient techniques. The engine is non-Euclidean capable to some degree; also it supports true displacement mapping for sectors as a means to virtualize geometry that affects collisions. The engine is also carefully designed to be easy and convenient to develop for, yet versatile and adaptive to any needs.
I was upgrading my map importer to support True Room-Over-Room in newer EDuke32 maps. Brahma levels offer a lot of freedom and ease at making various floor/ceiling portals (in addition to "multilevel" walls), but as the implementation and map format are totally different, handling TROR requires a careful conversion.
WGFang is a massive level by William Gee with four levels of TROR. Brahma renders this map a lot faster that Build/Polymost renderer, albeit quite buggy at the moment.