Systems and methods for self-intersection avoidance in ray tracing

Abstract

Aspects include systems, methods, and media for implementing methods relating to detection of invalid intersections during ray tracing. Invalid intersections can arise from imprecision in computer-based number representation, causing ray origins to be located inappropriately. In some aspects, a ray can be associated with information relating to an expected angle between the ray's direction and a normal for a to-be-identified primitive intersected by that ray. If the angle between the ray's direction and the normal of an intersected primitive is within expectations, then that information can be used in predicting whether the intersection is valid. Such expectation information can be presented as a single bit determined by a shader performing a dot product of the ray and a normal of a primitive intersected by a parent ray, or can be obtained as a by-product of ray/primitive intersection testing. Such information also can be based on whether the shader is emitting to have reflection or refraction type ray behavior.