Adobe 12040118 - After Effects Standard, Tutorial

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Jeff Almasol provides a script that automatically processes expressions, making specified changes. For example, the script can be used to
automatically remove or enable disabled expressions. For more information, see Jeff Almasol’s
redefinery website .
Add, disable, or remove an expression
To add an expression to a property, select the property in the Timeline panel and choose Animation > Add Expression or press Alt+Shift+=
(Windows) or Shift+= (Mac OS); or Alt-click (Windows) or Option-click (Mac OS) the stopwatch button next to the property name in
the Timeline panel or Effect Controls panel.
To temporarily disable an expression, click the Enable Expression switch . When an expression is disabled, a slash appears through the
switch .
To remove an expression from a property, select the property in the Timeline panel and choose Animation > Remove Expression, or Alt-click
(Windows) or Option-click (Mac OS) the stopwatch button next to the property name in the Timeline panel or Effect Controls panel.
Edit an expression with the pick whip
If you are not familiar with JavaScript or the After Effects expression language, you can still take advantage of the power of expressions by using
the pick whip. You simply drag the pick whip from one property to another to link the properties with an expression, and the expression text is
entered in the expression field at the insertion point. If text is selected in the expression field, the new expression text replaces the selected text. If
the insertion point is not in the expression field, the new expression text replaces all text in the field.
Drag the pick whip to a property to create a link to the value of the property.
You can drag the pick whip to the name or value of a property. If you drag to the name of a property, the resulting expression displays all the
values as one. For example, if you drag the pick whip to the name of the Position property, an expression like the following appears:
thisComp.layer("Layer 1").transform.position
If you drag the pick whip to one of the component values of the Position property (such as the y value), an expression like the following appears, in
which both the x and y coordinates of the property are linked to the y value of the Position property:
temp = thisComp.layer("Layer 1").transform.position[1];
[temp, temp]
If the layer, mask, or effect that you drag the pick whip to does not have a unique name in its local context, After Effects renames it. For example,
if you have two or more masks named “Mask” on the same layer, and you drag the pick whip to one of them, After Effects renames it “Mask 2”.
The format of expressions created by the pick whip is determined by the Expression Pick Whip Writes Compact English preference (Edit >
Preferences > General (Windows) or After Effects > Preferences > General (Mac OS)). By default, the pick whip creates compact English
expressions, which use the names for properties as they appear in the Timeline panel for the properties within an expression. Because these
names are coded into the application and never change, these expressions can work when After Effects is running in another language. Any
property names that you can change are enclosed in double quotation marks and remain the same in any language. If you don’t plan on sharing
your projects across languages, you can deselect this preference. This preference does not affect effect names or effect properties.
Here is an example in compact English:
thisComp.layer("Layer 1").transform.position
Here is the same expression, not in compact English:
thisComp.layer("Layer 1")("Transform")("Position")
Note: Because the default is to use compact English, this document uses compact English in most examples and illustrations.
1. Drag the pick whip to another property in the Timeline panel or Effect Controls panel.
2. Optionally, modify the default expression in the expression field.
Note: If you use the pick whip to create an expression to refer to a layer, and that layer has the same name as another layer in the same