Patent ID: 7884819

Claim:
A method of determining a color of a pixel in a ray tracing image processing system, comprising: issuing a primary ray into a three dimensional scene through the pixel; determining an initial color value for the pixel based on a color value of a first primitive intersected by the primary ray; issuing a secondary ray into the scene from the primitive intersected by the primary ray; by operation of one or more computer processors, updating the color value for the pixel based on a color value of a second primitive intersected by the secondary ray and a reflective or refractive scaling factor having a predetermined association with the first primitive intersected by the primary ray, and not based on a reflective or refractive scaling factor of the second primitive; issuing a further secondary ray into the scene from the primitive intersected by the secondary ray; and updating the color value for the pixel based on a color value of a third primitive intersected by the further secondary ray and a second reflective or refractive scaling factor based on the first primitive and the second primitive, and not based on a reflective or refractive scaling factor of the third primitive.