How DOOM fire was done

The DOOM fire effect on the PlayStation 1 was created using a simple framebuffer array representing heat values that propagate upwards to simulate fire. This technique, inspired by classic demoscene effects, uses a palette of colors from black to white through yellow, orange, and red to depict fire particles cooling as they rise. Randomness in heat decay and propagation spread adds realism, allowing effects like wind simulation. The article highlights the PSX team's clever use of extra CPU cycles to implement this visually impressive effect and references reverse-engineered code and improved versions for study.