8

Extended Parameters Rollout (Standard Material) 1313
These can be used to create Standard materials
with realistic transparency.
Additive Opacity and the Alpha Channel
By default, additive opacity does not generate an
alpha value. In other words, the alpha value is zero,
indicating no transparency. This gives correct
results with backgrounds in renderings, but if you
want to composite objects with additive opacity
using
video post (page 3–307) or a different
compositing program, you might want to have
additive opacity render with transparency. To do
so, add the following line to the [Renderer] section
of the
3dsmax.ini file, and then restart 3ds Max:
AlphaOutOnAdditive=1
To revert to the default method of rendering
additive opacity, in the
3dsmax.ini file, change the
valueofAlphaOutOnAdditivebackto0(zero),
and then restart 3ds Max.
Inter face
Advanced Transparency group
These controls affec t the
opacity fa l loff (page
3–1078)
of a transparent material.
Note: For the Translucent shader (page 2–1326) ,
these controls do not appear. They are replaced by
the
Translucency controls (page 2–1332) on the
Basic Parameters rollout.
Fa lloff—Chooseswhetherfalloffisinorout,and
how great it is.
•
In—Increases transparency toward the inside of
the object, as in a glass bottle.
•
Out—Increases transparency toward the outside
of the object, as in a cloud of smoke.
Amt (Amount)—Specifies the amount of
transparency at the outside or inside extreme.
Ty pe—Thesecontrolschoosehowtransparency
is applied.
•
Filter (page 3–1033) computes a filter color that
it multiplies by the color behind the transparent
surface. Click the color swatch to change the
filter color. Click the button to assign a map to
the filter color component.
The filter, or transmissive color, is the
color transmitted through transparent or
semi-transparent materia ls such as glass. You
can use the filter color w ith volumetric lighting
to create effects such as colored light through
astained-glasswindow.
Ray-traced shadows
(page 3–1094)
cast by t ransparent objects are
tinted with the filter color.
A shadow’s color is chan ged with a red filter color.
• Subtract ive (page 3–1111) subtracts from the
color b ehind the transparent surface.
•
Additive (page 3–1000) adds to the color
behind the transparent surface.
Index of Refraction—Sets the index of refraction
(IOR) used by refraction maps and raytracing.