Cornell Box Bounce Data

Michael Callahan

This is an RGB approximation of the Cornell Box using only direct lighting and shadows.

The following are the light contribution for the same Cornell Box at various bounce depths (from the camera). The contributions are not attenuated for distance or material color, and are scaled independently, so the brightnesses between pictures are not correlated. The images were computed at 400 samples/pixel.

Interestingly enough, after 4-6 bounces the light contribution is fairly uniform. It appears that doing more than 6 bounces on this scene wouldn't affect the image quality. A neat hack would be to compute an ambient term from the average light value returned by the 7th-8th bounce, terminate all the rays at that point, and use the computed average value as an ambient term. That might not be the case for other scenes however.

1 bounce.

2 bounces.

3 bounces.

4 bounces.

5 bounces.

6 bounces.

7 bounces.

8 bounces.