2008

Matte Object
Matte object reveals part of the background, making the hamburger geometry appear
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 from behind some portion of
the background, such as a building, you would create a matte object that
matches the building. You then place the animated 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 box is set, shadows cast on the matte object are applied to
the alpha channel. This lets you render maps with alpha shadows that you
7846 | Glossary