Re:Building a PS1 style retro 3D renderer
by rasz on Thursday December 09, 2021 @02:08AM
(#29494692)
From the horses mouths (minus Abrash/Carmack) 'HandmadeCon 2016 - History of Software Texture Mapping in Games' https://www.youtube.com/watch?v=xn76r0JxqNM
Wolfenstein and Doom are 100% correct because Carmack 'cheated' by deciding to never look down/up or draw slopes :-) so whole game is drawn with 'lines of constant Z'. Or as they put it
Chris Hecker (Microsoft/Maxis/etc): that's a classic Carmack thing which is like Fuck those general problems, Im gonna solve this other problem perfectly
John Miles (ORIGIN/Miles Design/etc): Its all about not doing the math, we were still at a point in time when you won by not doing the math
Wolfenstein's correct texture mapping is due to it using raycasting in a 2D plane and rendering scaled vertical strips of texture, which just happens to be perspective correct because you only ever have surfaces at 90deg angles in the vertical.
As to why those extra triangles weren't used for detailing, it's likely because that would take up extra level data. Tessellation of an existing triangle into smaller triangles doesn't.