Hexafaceted sprite angle support.
3DGE has 16 angles for modders. ZDoom has 16 angles for modders. Even Doom Legacy has 16 angles for modders. To this end, let us stop being chumps.
Here's a screencap from the ZDoom wiki which establishes how the system works in that, and Doom Legacy's matches everything (except for SRB2's L/R, which I have added to the diagram). I haven't been able to find any modding resources for 3DGE to confirm, but it would make sense that it behaves the same way.
Also, some minor memory efficiency fixes to both rotsprite and ordinary sprite rotations.
hexang.wad (testsprites generously donated by one of motorroach's projects)