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Compound Materials 1587
your shadows against a background image, such
as video. I t lets you tint your shadows to match
pre-existing shadows in the image.
Reflection group
Controls in this group determine whether the
matte surfaces can have reflections. You create
matte reflections using a shadow map.
Tip: Matte reflections don’t successfully create an
alpha channel unless you render them against a
black background.
Amount—Controls the amount of reflection to
use. This is a percentage that can range from 0 to
100. This control is unavailable un less you have
assigned a map. Default=50.
You can animate this parameter.
Map—Displays the Material/Map Browser (page
2–1412) so you can assign a map to use for
reflections. The reflection is independent of the
environment unless you cho ose a Reflect/Refract
(page 2–1695) or Flat Mirror map (page 2–1695).
Compound Materials
Compound materials combine two or more
sub-materials. Compound materials are similar to
compositor maps (page 2–1687),buttheyexistat
the material level. Applying a compound material
to an object creates a compound effect that often
uses mapping. You load or create compound
mater ials using the Material/Map Browser.
Using a filter control, you can choose whether the
Browser lists maps or materials or both.
Different types of materials create different effects,
behave in particular ways, or are provided as ways
to combine multiple materials.
Note: The sub-material buttons and sub-map
buttons for most materials and maps have check
boxes beside each button. These let you tur n
that branch of the material or map on or off. For
example, in the Top/Bottom material, the Top
Material and Bottom Material buttons each have
check boxes. Similarly, the Checker map has two
map buttons, one for each color. Each button has a
check box beside it that lets you disable that color’s
map.
Thesearethedifferenttypesofcompound
materials:
Blend (page 2–1588):Combinestwomaterialsby
mixing their pixel colors, a s Mix maps do.
Composite (page 2–1589):Mixesupto10
materials, using additive colors, subtrac tive colors,
or opacity mixing.
Double-Sided (page 2–1591): Stores two materials.
One material is rendered on the object’s outer
faces (the usual side for one-sided materials, as
determined by face normals), and the other is
rendered on the object’s inner faces.
Morpher Material (page 2–1592):Morpher
materials use the Morpher modifier (page 1–729)
to manage mult iple materials over time.
Multi/Sub -Ob ject (page 2–1594):Letsyouassign
more than one material to the same object. Stores
two or more sub-materials, which you assig n
at the sub-object level by using the Mesh Select
(page 1–719) modifier. You can also assig n t he
sub-materialstowholeobjectsbyusingthe
Material modifier (page 1–714).
Shellac (page 2–1597):Superimposesonematerial
on another.
Top/Bottom (page 2–1599): Stores two materials.
One material is rendered on an object’s top faces
and the other is rendered on the object’s bottom
faces, depending on whether a face normal points
up or down.