Patent ID: 8207968

Claim:
A computer-implemented method for generating an irradiance cache, comprising: performing, by one or more computing devices: determining an irradiance gradient at a query point of a scene to be rendered; determining cache points in the irradiance cache that are within a specified neighborhood of the query point as neighbor cache points to the query point; determining that the irradiance gradient at one or more of the neighbor cache points along a vector in a particular direction is the same as or substantially similar to the irradiance gradient at the query point; expanding a radius of a region of influence of the query point along vectors in the particular direction to thus define an elliptical region of influence at the query point in response to determining that the irradiance gradient at the one or more neighbor cache points along the vector in the particular direction is the same as or similar to the irradiance gradient at the query point; and adding a new cache point corresponding to the query point to the irradiance cache, wherein the new cache point indicates the elliptical region of influence.