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1370 Chapter 16: Material Editor, Materials, and Maps
Maximum Depth—
Sets the maximum recursion
depth. Increasing this value potentially increases
the realism of your rendered scene, at a cost of
rendering time. You can reduce this value to reduce
rendering t ime. Range=0 to 100. Default=9.
Cutoff Thre shold—Sets a cutoff threshold for
adaptive ray levels. If the contribution of any ray
to the final pixel color drops below the cutoff
threshold, the ray is terminated. Default: 0.05 (5%
of the final pixel color). This can speed up y our
rendering time considerably.
Co lor to use at Max D epth—As a rule, when a ray
reaches the maximum depth, it is rendered the
same color as the background environment. You
can override the color returned at maximum depth
by either select ing a color, or setting an alternative
environment map. This can make the "lost" ray
invisible in the scene.
Tip: If you are having trouble with getting co mplex
objects to render, especially glass, specify the
maximum recursion color to something obvious,
like magenta, and your background color to
something that contrasts, like cyan. The chances
arethatalotofyourraysaregettinglostineither
maximum recursion or just being shot off into the
world, totally missing anything you think they
should strike. Try rendering the scene again. If
this is the problem, try reducing the Maximum
Depth value.
•
Specify—Specifies what color the raytracer
returns when the ray is considered lost or
trapped. Click the color swatch to change this
color.
•
Background—(The default.) Returns the
background color when the ray is considered
lost or trapped. For Raytrace material, the
background color is the global env ironment
background or the environment specified
locallyforthematerial. ForRaytracemap,
the background color is either the global
environment background, or is set locally in the
Raytr acer Parameters rollout (page 2–1514) .
Global Ray Antialia ser group
Controls in this group let you set global antialiasing
for r ay tr aced maps and mater ials.
Above: No antialiasing
Below: Antial iasing of re fle ctions
Tip: Tur n ing on Supersample for a R ay tr aced
material (in the
Rayt race Basic Parameters
rollout (page 2–1355)
)usuallyprovidesadequate
antialiasing. Use one of the ray trace antialiasers
(Fast Adaptive or Multiresolution Adaptive) when
you want to blur reflections or refractions.
On—When on, uses antialiasing. Default=off.
Drop-down list—Chooses which antialiasing
settings to use. There are two a lternatives:
•
Fa st Adaptive Antialiaser—(The default.) Uses
theFastAdaptiveantialiaser.
•
Multiresolution Adaptive Antialiaser—Uses the
Multiresolution Adaptive antialiaser.
...—The button with the ellipsis to the right of
the drop-down list displays another dialog to let
you set ant ialiasing controls globally. The dialog
displayed depends on which alternative you chose
in the drop-down list, as follows: