NVIDIA Corporation
CONSTRAINED BSDF SAMPLING

Abstract:

Systems and methods are provided to perform constrained BSDF sampling in relation to various algorithms, and specifically in relation to ray tracing algorithms. In some embodiments, a method is provided to generate samples by: determining a spherical polygon on a unit hemisphere; determining, on a unit circle, a projected area corresponding to the spherical polygon on the unit hemisphere; determining a parameterization of the projected area of the spherical polygon on the unit circle; generating samples in the projected area based on the parameterization; and generating samples in the spherical polygon. The unit circle is abase of the unit hemisphere, and the projection of the projected area is along a vector perpendicular to the unit circle. The generated samples in the spherical polygon correspond to the samples in the projected area. The method may further include evaluating a rendering equation based on the generated samples in the spherical polygon.