I'd be interested to read about the very old school (pre-Wolfenstein) 3D engines used in DOS-era simulation games such as LHX Attack Chopper, for example about the data / acceleration structures they used to represent the 3D worlds. Any resources you know of? A cursory Google search did not reveal much.
I remember programming filled 3D graphics in the DOS days using tutorials like the PC-GPE, but at the time my understanding of things like matrices, frustum culling, proper clipping or acceleration structures were pretty much nonexistent; if I had multiple objects to draw I'd just store them to a flat array.
Nowadays it's common to use a quadtree or octree, but when dealing with 16-bit segmented memory, it wouldn't be that straightforward.