Patent ID: 8441482

Claim:
A method for use in ray tracing, comprising: receiving information for a child ray that was emitted during shading of an intersection between a parent ray and a surface in a 3-D scene; producing a location of an intersection between the child ray and a surface in the 3-D scene, the location represented by one or more numbers within a precision of a machine number format used by a machine producing the location for the intersection; characterizing an angle between the child ray and a normal of the surface at the child ray intersection; categorizing the child ray intersection as a potentially valid or as a potentially invalid intersection based on the characterization of the angle between the child ray and the surface normal of the child ray intersection, and information characterizing the direction of the child ray compared with a normal of the surface at the intersection involving the parent ray; and proceeding with ray tracing in the 3-D scene responsive to the categorizing.