Sampling the Visible Sphere

from blog Fred Akalin, | ↗ original
(Note: this article is a summary of this thread on ompf2.) The usual method for sampling a sphere from a point outside the sphere is to calculate the angle of the cone of the visible portion and uniformly sample within that cone, as described in Shirley/Wang. However, one detail that is glossed over is that you still need to map from the sampled...