Patent ID: 7755626

Claim:
A computer-implemented method of creating a computer graphics image, the method comprising: creating, in a computer memory, an object fragment representing a portion of an object in a scene from a virtual camera viewpoint, wherein the object fragment includes a visible surface position in the scene; creating, in the computer memory, a set of light fragments for a light source, the set of light fragments representing a portion of the scene from a viewpoint associated with the light source, wherein each light fragment includes a position in the scene; defining, using a computer processor operatively connected to the computer memory, a frustum between the visible surface position of the object fragment in the scene and the light source, the frustum including a shape with an apex located on the visible surface position of the object fragment and a base defined by a size and a position of the light source; selecting, using the computer processor, a portion of the set of light fragments having positions within the frustum; determining, using the computer processor, a shading value for the object fragment from the selected portion of the light fragments; determining, using the computer processor, an unshaded visual attribute value for the object fragment; and altering, using the computer processor, the unshaded visual attribute value of the object fragment according to the shading value of the object fragment, wherein altering the unshaded visual attribute value of the object fragment comprises scaling the unshaded visual attribute value of the object fragment according to the shading value of the object fragment.