I am wondering how professional light visualizer software (like Capture Argo - WYSIWYG - Realizzer - LightConverse) project the lights on the objects (like stage, floor, people), even projecting the various gobos (shapes).
Here are some screenshots:
How do they calculate the various intersections, and project beams for so many light sources in an efficient way? What's the simplest way?
I assume they are projecting a texture but how?