User Guide

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ADOBE AFTER EFFECTS 5.0
User Guide
Understanding default rendering order
The order in which After Effects renders the various parts of a composition can affect the
look of some visual effects in a rendered movie. An understanding of how After Effects
renders a composition will help you get the effects you want.
In rendering a composition, After Effects processes 2D layers in the order in which they
are listed in the Timeline window, starting at the bottom of the list. (However, After Effects
processes 3D layers in Z order within their 3D bins. For more information, see “3D
rendering” on page 303.) In processing each layer, After Effects processes changes from the
top down, as these three categories appear in the Timeline window: first the masks, then
effects, and finally the transformations. The transfer modes and track mattes are processed
after that. For elements with multiple effects, After Effects processes these in the order in
which they are listed in the Effect Controls and the Timeline windows.
Changing the rendering order
Sometimes, projects require a visual effect that cannot be achieved using the default
rendering order. For example, you may be constructing an animation in which you want
a rotated object to have a drop shadow effect. By default, After Effects renders an effect
before rotation, which would create shadows with different orientations.
A. Original layer B. Drop shadow applied at effect stage C. Rotation applied at transform stage
results in the shadow rotating with the layer
ABC
UG.book Page 343 Wednesday, February 21, 2001 12:05 PM