Incremental frustum-cache acceleration of line integrals for volume rendering

1. Field of the Invention A method for rendering participating media effects is disclosed. At least one object having a surface is defined and a lattice, aligned with a camera, is also defined that encompasses the at least one object. A volumetric line integral is computed from the camera to lattice points in a neighborhood of a particular point on the surface of the object to obtain a value. The obtained value is filtered to obtain a volumetric line integral value for the particular point on the surface. Additionally, the set of values may be cached in memory and may be used in computing additional volumetric line integrals when applicable. The set of values determined for lattice points is filtered to determine the volumetric line integral value for a particular point on the surface.