Patent ID: 6850244

Claim:
In a graphics processing system, a method of altering color values of a pixel along a surface function having an interpolated normal vector, comprising: adding a displacement vector to the interpolated normal vector to produce a perturbed normal vector, the displacement vector calculated from the equation: D =( fu*Pu * scaleu)+( fv*Pv * scalev), where D is the displacement vector, Pu and Pv are perpendicular vectors tangent to the surface function at the pixel, fu and fv are displacement values along Pu and Pv, respectively, and scaleu and scalev are scaling values; iterating bump map coordinates (bu, bv) of texels to obtain the displacement values fu and fv, respectively; retrieving the scaling values scaleu and scalev from a scale register; and generating color values for the pixel based on the perturbed normal vector instead of the interpolated normal vector.