Cornell box

The Cornell box is a test aimed at determining the accuracy of rendering software by comparing the rendered scene with an actual photograph of the same scene,[1] and has become a commonly used 3D test model.

It was created by Cindy M. Goral, Kenneth E. Torrance, Donald P. Greenberg, and Bennett Battaile at the Cornell University Program of Computer Graphics for their paper Modeling the Interaction of Light Between Diffuse Surfaces published and presented at SIGGRAPH'84.

The exact settings are then measured from the scene: emission spectrum of the light source, reflectance spectra of all the surfaces, exact position and size of all objects, walls, light source and camera.

Another common version first used to test photon mapping includes two spheres: one with a perfect mirror surface and one made of glass.

Today, the Cornell box is often used to demonstrate renderers in a similar way as the Stanford bunny and the Utah teapot are; computer scientists often use the scene just for its visual properties without comparing it to test data from a physical model.