Radiosity (computer graphics)

Goral, Torrance, Greenberg and Battaile's radiosity paper, Cornell University, SIGGRAPH 1984 Ray tracing excels at mirrors and sharp shadows but misses the soft light that bounces between matte walls. Radiosity borrowed a method from heat transfer: divide every surface into patches, work out how well each pair can see each other, and solve for the light each one passes on. The result is the gentle, even light of a real room. Its test scene became famous too. The Cornell box, a simple room with colored walls, made color bleeding visible, one wall tinting its neighbors, and later versions were compared with images from a calibrated camera. The box pictured is a modern render of that scene.