Interior Mapping: rendering real rooms without geometry (2018)

The trick is to add a simple limitation: with interior mapping, ceilings and walls are at regular distances. This saved a little bit of performance and helped achieve a good framerate with interior mapping even back in 2007 when I came up with this technique. After all these years it’s really cool to finally see my interior mapping technique in action in a big game production!

Source: www.gamasutra.com