RayTmaxKHR

RayTmaxKHR

A variable decorated with the RayTmaxKHR decoration will contain the parametric t_max value of the ray being processed. The value is independent of the space in which the ray origin and direction exist. The value is initialized to the parameter passed into the pipeline trace ray instruction.

The t_max value changes throughout the lifetime of the ray that produced the intersection. In the closest hit shader, the value reflects the closest distance to the intersected primitive. In the any-hit shader, it reflects the distance to the primitive currently being intersected. In the intersection shader, it reflects the distance to the closest primitive intersected so far or the initial value. The value can change in the intersection shader after calling OpReportIntersectionKHR if the corresponding any-hit shader does not ignore the intersection. In a miss shader, the value is identical to the parameter passed into the pipeline trace ray instruction.