Patent ID: 7982734

Claim:
A method, comprising: for each of a plurality of pixels within a shadowed region of a shadow-receiving plane, wherein the shadowed region corresponds to an area of the receiving plane from which light from a light source is at least partially attenuated by an occluding plane: determining, by a computer, a size and shape of a spatially-varying convolution area corresponding to a ray projection projected from a respective pixel of the plurality of pixels through an occluding plane onto a light source plane, wherein the determined size of the convolution area for the respective pixel is different than the determined size of the convolution area for another of the plurality of pixels, and wherein the determined size of the convolution area varies according to a size of the light source and a distance between the occluding plane and the light source; computing, by the computer, a shadow value for the respective pixel based on a plurality of light attenuation values for the occluding plane within the convolution area, wherein the light attenuation values each specify a level of attenuation for light from the light source plane intersecting a corresponding pixel of the occluding plane; and rendering, by the computer, the shadowed region of the receiving plane according to the respective shadow values.