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Materials 971
Materials
Spheres with variations of the standard material type (no maps
used):
Green sphere: High Glossiness
Red sphere: Constant shading
Blue sphere: 60% opacity
Yellow sphere: Wireframe mode, slight self-illumination
A material is data that you assign to the surface
or faces of an object so that it appears a certain
way when rendered. Materials affect the color of
objects, their glossiness, their opacity, and so on.
A standard material consists of ambient, diffuse,
and specular components. You can assign maps to
the various components of ast a ndard material.
The standard material is the default material
in the six sample slots of the Ma terial Editor.
However, you can change the type of material
you’re working on by clicking the button labeled
Type below the sample slots. This displays the
Material/Map Browser, and lets you select from a
list of alternative material ty p es.
You can also change the type of material you’re
working on by clicking the Get Material button
below the sample slots. This displays the
Material/Map Browser, and lets you select from a
list of alternative material ty p es.
Matte Object
Matte object reveals par t of the background, making the
hamburger geometry appea r to be inside the oven.
A matte object is invisible but blocks any geometry
behind it. However, it does not block the
background.
For example, you might make a complex scene
for the background of your animation, render
it once, then assign the resulting bitmap as a
background using only a few animated objects
during the rendering of the animation. If you
then needed one of your objects to appear f rom
behind some portion of the background, such as
a building, you would create a matte object that
matches the building. You then place the anim ated
object behind it. The bitmap image of the building
appears, but the animated object is blocked until it
moves from behind the matte object.
Matte objects, though invisible, can cast shadows.
Matte objects can also receive shadows. When the
Matte/Shadow material’s Affect Alpha check bo x is
set, shadows c ast on the matte object are applied to
the alpha channel. This lets you render maps with
alpha shadows that you can composite later. To
properly generate shadows on a matte object, turn
off the Opaque Alpha check b ox and then set the
Affect Alpha check box.