Abstract: Aspects include systems, methods, and media for implementing methods relating to increasing consistency of results during intersection testing. In an example, vertexes define edges of primitives composing a scene (e.g., triangles defining a mesh for a surface of an object in a 3-D scene). An edge can be shared between two primitives. Intersection testing algorithms can use tests involving edges to determine whether or not the ray intersects a primitive defined by those edges. In one approach, a precedence among the vertexes defining a particular edge is enforced for such intersection testing. The precedence causes an intersection tester to always test a given edge in the same orientation, regardless of which primitive defined (at least in part) by that edge is being intersection tested.

Abstract: In one aspect, a method provides for iteratively taking passes of samples for each pixel of a set of pixels. Initially, the set of pixels can be all of the pixels of an image. For each pixel, an accumulated color at the beginning of a pass and at the end of a pass can be compared. If a difference between these is within a threshold, a convergence count, which begins at an initial value, is reduced. If the difference is not within the threshold, then the convergence count is reset. When the convergence count reaches a preset value, then the pixel is considered converged and removed from the set. However, if a pixel adjacent to a converged pixel fails a convergence test, then the converged pixel is reset to unconverged and returned to the set and at least a minimum number of additional sample passes are undertaken for that pixel.

Abstract: In one aspect, a method provides for iteratively taking passes of samples for each pixel of a set of pixels. Initially, the set of pixels can be all of the pixels of an image. For each pixel, an accumulated color at the beginning of a pass and at the end of a pass can be compared. If a difference between these is within a threshold, a convergence count, which begins at an initial value, is reduced. If the difference is not within the threshold, then the convergence count is reset. When the convergence count reaches a preset value, then the pixel is considered converged and removed from the set. However, if a pixel adjacent to a converged pixel fails a convergence test, then the converged pixel is reset to unconverged and returned to the set and at least a minimum number of additional sample passes are undertaken for that pixel.

Abstract: Aspects include systems, methods, and media for implementing methods relating to increasing consistency of results during intersection testing. In an example, vertexes define edges of primitives composing a scene (e.g., triangles defining a mesh for a surface of an object in a 3-D scene). An edge can be shared between two primitives. Intersection testing algorithms can use tests involving edges to determine whether or not the ray intersects a primitive defined by those edges. In one approach, a precedence among the vertexes defining a particular edge is enforced for such intersection testing. The precedence causes an intersection tester to always test a given edge in the same orientation, regardless of which primitive defined (at least in part) by that edge is being intersection tested.

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.