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've been developing voxel heightmap support in Brahma since February 2018, taking long breaks, and even now it remains incomplete, although I've done useful stuff like proper wall trimming and sloped heightmaps on both floors and ceilings. My current routine is quite slow (about 20 cc/pixel without MT), but there's enough room for later optimizations. Build engine once had rudimentary heightmaps, but the implementation was very limited and was removed shortly, being replaced with slopes.