Path (Ray) Tracing by Disney

[Brian Drysdale]

An animation (in an old style) explaining what Disney call path tracing is used..

 

[dan kessler]

Ray tracing is probably the oldest and most fundamental cg 3d rendering
method that exists. To be slightly more specific, rays are computed
for each pixel in an image. There are other rendering schemes, some much
faster, but ray tracing is good for photorealism and accurate shadows and reflections.