Adobe 12040118 Tutorial - Page 561

Expression language reference Global objects, attributes, and methods (expression reference) Time conversion methods (expression reference) Vector Math methods (expression reference) Random Numbers methods (expression reference) Interpolation methods (expression reference) Color Conversion methods (expression reference) Other Math methods (expression reference) Comp attributes and methods (expression reference) Footage attributes and methods (expression reference) Layer Sub-objects attributes and methods (expression reference) Layer General attributes and methods (expression reference) Layer Properties attributes and methods (expression reference) Layer 3D attributes and methods (expression reference) Layer Space Transforms methods (expression reference) Camera attributes and methods (expression reference) Light attributes and methods (expression reference) Effect attributes and methods (expression reference) Mask attributes and methods (expression reference) Property attributes and methods (expression reference) Key attributes and methods (expression reference) MarkerKey attributes (expression reference) Use the After Effects expression elements along with standard JavaScript elements to write your expressions. You can use the Expression Language menu at any time to insert methods and attributes into an expression, and you can use the pick whip at any time to insert properties. If an argument description contains an equal sign (=) and a value (such as t=time or width=.2), then the argument uses the included default value if you don't specify a different value. Some argument descriptions include a number in square brackets-this number indicates the dimension of the expected property or Array. Some return-value descriptions 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. The W3Schools JavaScript reference website provides information for the standard JavaScript language, including pages for the JavaScript Math and String objects. Global objects, attributes, and methods (expression reference) To the top comp(name) Return type: Comp. Argument type: name is a String. Retrieves another composition by name. footage(name) Return type: Footage. Argument type: name is a String. Retrieves a footage item by name. thisComp Return type: Comp. Represents the composition containing the expression. thisLayer Return type: Layer, Light, or Camera. Represents the layer containing the expression. Because thisLayer is the default object, its use is optional. For example, you can start an expression with thisLayer.width or width and get the same result. thisProperty Return type: Property. Represents the property containing the expression. For example, if you write an expression on the Rotation property, you can start an expression with thisProperty to refer to the Rotation property. time Return type: Number. Represents the composition time, in seconds, at which the expression is being evaluated. colorDepth Return type: Number. Returns the project color depth value. For example, colorDepth returns 16 when the project color depth is 16 bits per channel.