lightsample
Lightsample is a concept in computer graphics and optical simulation referring to the process of selecting sample directions and light sources to estimate the illumination at a shading point. In rendering, lightsampling is a key component of evaluating the rendering equation using Monte Carlo methods.
Two broad categories are commonly used: light-source sampling and direction sampling. Light-source sampling picks individual light
Techniques used to implement lightsampling include uniform sampling, importance sampling (sampling from the light distribution or
Applications include physically based rendering, where accurate lightsampling improves realism and reduces noise in global illumination.
Challenges include variance and noise, especially in scenes with many small lights or complex caustics, and
See also: global illumination, Monte Carlo integration, ray tracing, BRDF, environment mapping.