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Ray-Traced Shadow Parameters Rollout 1363
Ray-Traced Shadow Parameters
Rollout
Create a ligh t . > General Parameters rollout > Ray Traced
Shadows chosen > Ray Traced Shadow Params rollout
Ray-traced shadows
The Ray-Traced Shadow Parameters rollout
appears w hen you have chosen raytracing as the
shadow-generation technique for a light. You
select this in the General Par ameters rollout (page
2–1331).
For greater control of ray-traced shadows, use
Advanced Ray-Traced Shadows (page 2–1356).
Inter face
Bias—Ray-Trace Bias (page 3–1000) moves the
shadow toward or away from the shadow-casting
object (or objects).
If the Bias value is too low, shadows can "leak"
through places they shouldn’t, producing moire
patterns or making out-of-place dark areas on
meshes. If Bias is too high, shadows can "detach"
from an object. If the Bias value is too extreme i n
either direction, shadows might not be rendered
at all.
2-Sided Sha dows—When on, backfaces are not
ignored when calculating shadows. Objects seen
from the inside are not lit by lights from the
outside. This costs a bit more render time. When
off,backfacesareignored.Renderingisquicker,
but outside lights illuminate object interiors.
Default=on.
The faces inside the sliced sphere do not cast shadows if 2-Sided
Shadows is not selec ted.
Max Quadtree Depth—Adjusts the depth of the
quadtree (page 3–999) used by the ray-tracer.
Greater quadtree depth values can improve
ray-tracing time at the cost of memory use.
However, there is a depth value where t he
performanceimprovementisoffsetbythetimeit
takes to generate the quadtree itself. This depends
on the geometry of the scene. Default=7.
Tip: Omni lights can generate up to six quadtrees,
so they generate ray-traced shadows more slowly
than spotlig hts. Avoid using ray-traced shadows
w ith omni lights un less your scene requires this.
Shadow Map Parameters Rollout
Create a light. > General Parameters rollout > Shadow
Map chosen > Shadow Map Params rollout
The Shadow Map Para meters rollout is displayed
when you have chosen shadow mapping as the