What is the best value for the Spawn Limit when using materials that scatter light?
Although Photopia has the ability to “spawn” more than a single ray, we recommend that the Spawn Limit be left at its default value of 1 for all material types, including diffuse. Use the number of initial source rays to determine the level of detail of your analysis. For a given number of rays passing through your system, you will get a better sampling of reflection points when using 1 spawned ray, thus getting the best results in the shortest amount of time. Consider an example of sending 10 rays in a general direction toward a surface and spawning 1 ray for each reflection. You end up with 10 different reflection points and 10 reflected rays. However, if you use a spawn limit of 10 and initiate one-tenth the number of source rays, then you end up with 1 reflection point and 10 reflected rays. The latter was a faster analysis (at least if only 1 reflection was traced) however in a system that is attempting to model the real behavior of light with relatively few rays, it is preferred
