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1206 Chapter 15: Lights and Cameras
Turning off Color saves memory at rendering t ime.
Merge Dist.—The minimum distance between two
surfaces for them to be considered “distinct.” If two
surfaces are closer than this value, the shadow m ap
treats them as a single surface. When set to 0.0,
the mental r ay renderer automatically calculates a
distance value to use. Default=0.0 (automatic).
LargerMergeDistancevaluesreducememory
consumption, but can reduce shadow quality.
Low Merge Distance values increase memory
consumption and slow down rendering speed.
Samp./Pixel—The number of samples used to
generate a pixel in the shadow map. Higher values
increase the quality and detail of the shadow, at a
cost of render time. Default=5.
If a mapped shadow appears to be
aliased (page
3–1001)
,increasethevalueofSamples/Pixel.This
setting is especially useful when shadows are cast
by finely detailed geometry.
Optimi zati ons R ollout
Create panel > Lights > Create a light. > General
Parameters rollout > Select Advanced Ray-traced
Shadows or Area Shadows. > Optimizations rollout
The Optimizations rollout provides additional
controls for
Advanced Ray-traced Shadow
(page 3–1094)
and Area Shadow (page 3–1005)
generation.
See also
General Lighting Parameters (page 2–1175)
Shadow Parameters (page 2–1181)
Area Shadows Rollout (page 2–1202)
Advanced Ray-Traced Parameters Rollout (page
2–1200)
Interfa ce
Transparent Shadows group
On—When checked, transparent surfaces will cast
a colored shadow. O therwise, all shadows are
black.
Note: Shadows wi ll generate faster with this value
turned off.
A stained glass appears solid with the transparency
optimization turned off.
Antialiasing Threshold—The maximum color
difference allowed between transparent object
samples before
antialiasing (page 3–1001) is
triggered. Increasing the value of this color w ill
make the shadow less sensitive to ali asing artifacts