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Sampling (mental ray Renderer) 1099
effect is somewhat like the falloff of a soft-edged
spotlight.
ThedefaultSampleRangevalueis4.TheSample
Range value can be any floating-point number
from 0 to 20. Values of 2 to 5 are recommended.
Values below 3 can produce coarse-edged shadows.
You can reduce this effect by increasing the map
size.
Values greater than 5 can produce streaking and
moiré patterns. You can reduce this e ffect by
increasing the map size or the Bias value.
Rendering time increases exponentially as the
Sample Range value increases.
S ampl ing (menta l ra y Rend erer )
Sampling is an antialiasing technique. It provides
a "best g uess" color for each rendered pixel. The
mental r ay renderer (page 3–77) first samples the
scene color at locations within the pixel or along
the pixel’s edge, then uses a filter to combine the
samples into a single pixel color.
(In 3ds Max, this technique is called
"supersampling." Because the ment al ray
renderer performs sampling on a scene basis,
in the Material Editor, you
don’t need to turn
on supersampling for materials rendered using
mental ray.)
Scene rendered with low sampling is jagged and inaccurate.
Sampling range: 1/64 to 1/4
Same scene rendered with higher sampling shows smooth
edges.
Sampling range: 1 to 16
The mental ray renderer provides five filter
methods: Box, Gauss, Tr iangle, Mitchell, or
Lanczos. Box, the default, is also the quickest.
Mitchell is often the most accurate. The Box filter
combines samples evenly, without weighting them.
Eachoftheotherfiltersusesaparticularcurveto
weight samples before combining them.
Curves used to weight samples (thes e are approximate)