User Guide

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ADOBE AFTER EFFECTS 5.0
User Guide
• Italic text at the beginning of a description represents the return value type. Some return
values include a number in square brackets—this number specifies the dimension of the
returned property or array. If a specific dimension is not included, the dimension of the
returned array depends on the dimension of the input.
• Bold text represents the expression language element to type in your expression.
• (Bold Italic) text inside parentheses represents the argument(s), which is the type of
information that you need to add inside the parentheses. If an argument contains an equal
sign (=) and a value (such as t=time or width =.2), the argument uses the included default
value if you don’t specify a different value.
• {Italic and Roman} text inside curly brackets represents the argument description. Some
argument descriptions include a number in square brackets—this number indicates the
dimension of the expected property or array. If a specific dimension is not included, any
dimension will work.
• Roman text is a description and possibly an example of the element.
Global attributes and methods
Only a global attribute or method, or a constant value, can appear in an expression with
nothing to the left of it.
Global objects
Layer, Light, or Camera this_layer Represents the Layer itself. Because “this_layer” is the
default object, its use is optional. For example, you can start an expression with
“this_layer.width” or “width” and get the same result.
Comp this_comp Represents the composition containing the expression. For example,
you can start an expression with “this_comp.layer(2)”.
Number time Represents the composition time, in seconds, at which the expression is
being evaluated. See “Expression time” on page 319.
Number value Represents the value at the current time for the property containing the
expression. For example, you can include “value + 5” in an expression.
Comp comp(name) Retrieves another composition by name.
Footage footage(name) Retrieves a footage item by name.
UG.book Page 325 Wednesday, February 21, 2001 12:05 PM