System and method for antialiasing bump texture and bump mapping

摘要

A system and method for antialiasing bump texture and bump mapping which overcomes the disadvantages of previous methods of antialiasing bump maps without significantly expanding the required physical hardware needed for the calculations. A bump curvature value computed from the difference in heights between adjacent texels is applied to the specular shading calculations for bump maps. The bump curvature is used to open an "integration window" over the specular highlight of the bump. The resulting integral provides a highlight value which approximates the specular highlight. The highlight value is then added to the pixel shading value in the frame buffer. The process decreases the brightness of the highlights while increasing the overall brightness near the highlights, in a user-controlled blend that preserves the proper average effect of the specularity or reflectiveness. The process has no effect where there are no bumps or where the viewer is so close to the surface. Two user-supplied coefficients properly account for the content of the bump texture and the values of the surface materials coefficients.