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1460 Chapter 16: Material Editor, Materials, and Maps
raytraced reflections and refractions all have
their own preliminary antialiasing strategies.
Supersampling is an additional step that provides
a "best guess" color for each rendered pixel. The
supersampler’s output is then passed on to the
renderer, which performs a final antialiasing pass.
A single rendered pixel represents an area of
the scene’s geometry. The pixel c an stand in for
multiple colors, especially when it appears at the
edge of an object or a region of color . This is where
aliasing effects occur.
Whensupersamplingisturnedoff,3dsMaxsimply
looks at the center of the geometry covered by the
pixel, and uses that for the pixel color.
When you turn on supersampling, a supersampler
performs an additional antialiasing pass
on the material. You can choose one of
four supersamplers. As the name implies,
a supersampler takes additional samples of
geometr y color in or near each pixel, in order to
obtainamoreaccuratepixelcolorthatislessprone
to aliasing error.
Thesearethesupersamplingmethods:
Name
Descr iption
Adaptive Halton Spaces sample s along both X and Y a xes
according to a scattered, "quasi random"
pattern. Depending on Quality, the
number of samples can range from
4 to 40. This method is adaptive, as
described below.
Adaptive
Uniform
Spaces samples regularly, from a
minimum quality of 4 samples to a
maximum of 36. The pattern is not
square, but skewed slightly to improve
accuracy in the vertical and horizontal
axes. This method is adaptive, as
described below.
Name
Descr iption
Hammersley Spaces samples regularly along the X
axis,butalongtheYaxisitspacesthem
according to a scattered, "quasi ra ndom"
pattern. Depending on Quality, the
number of samples can range from 4 to
40. This method is not adaptive.
MAX 2 .5 Star
Thesampleatthecenterofthepixelis
averaged with four samples surrounding
it. The pattern is like the fives on dice.
This is the supersam pling m ethod that
was available in 3ds Max 2.5.
Regular sampling, as performed by the Adaptive
Uniform and MAX 2. 5 Star methods, is more prone
to a liasing than the irregular p atterns performed
by the Adaptive Halton and Hammersley methods.
You can set a variable Quality value for the
AdaptiveHalton,AdaptiveUniform,and
Hammersley methods. Quality can range from 0.0
to 1.0. A quality of 0.0 is minimal, with about four
samples per pixel. A quality of 1.0 is the highest
possible, w ith between 36 and 40 samples p er
pixel. High-quality supersampling is very time
consuming.
Another setting for t he Adaptive Halton and
Adaptive Uniform supersamplers is the Adaptive
toggle, which works in conjunction with the
Threshold spinner. When Adaptive is on, these
methods take fewer samples unless a change in
color is greater than the Threshold value. In that
case, they take the full number of samples specified
bytheQuality.Toreducetheamountoftimethe
supersampler spen ds, leave the Adaptive check
box on.