Layer General attributes and methods
- width
-
Return
type: Number.
Returns the width of the layer, in pixels. It is the same as source.width.
- height
-
Return
type: Number.
Returns the height of the layer, in pixels. It is the same as source.height.
- index
-
Return
type: Number.
Returns the index number of the layer in the composition.
- parent
-
Return
type: Layer, Light, or Camera.
Returns the parent Layer object of the layer, if there is one. Example: position[0] + parent.width
- hasParent
-
Return
type: Boolean.
Returns true if the layer has a parent or false if it doesn’t.
Use the hasParent attribute to determine if a layer has a parent. You can use this attribute even if there isn’t a parent layer at present. For example, the following expression indicates that the layer to which you apply it will wiggle based on the position of the layer’s parent. If the layer has no parent, then it will wiggle based on its own position. If the layer is given a parent later, then the layer’s behavior will change accordingly:
idx = index; if (hasParent) { idx = parent.index; } thisComp.layer(idx).position.wiggle(5,20) - inPoint
-
Return
type: Number.
Returns the In point of the layer, in seconds.
Note: In general, the value of outPoint is greater than the value of inPoint. However, if a layer is reversed in time, the value of inPoint is greater than the value of outPoint. Similarly, the value of startTime can be greater than the value of inPoint. - outPoint
-
Return
type: Number.
Returns the Out point of the layer, in seconds.
- startTime
-
Return
type: Number.
Returns the start time of the layer, in seconds.
- hasVideo
-
Return
type: Boolean.
Returns true if the layer has video, or false if it doesn’t.
- hasAudio
-
Return
type: Boolean.
Returns true if the layer has audio or false if it doesn’t.
- active
-
Return
type: Boolean.
Returns true if the layer’s Video switch
is
on and the current time is between the layer’s In point and Out
point; false otherwise. - audioActive
-
Return
type: Boolean.
Returns true if the layer’s Audio switch
is
on and the current time is between the layer’s In point and Out
point; false otherwise. - sampleImage(point, radius = [.5, .5], postEffect=true, t=time)
-
Return
type: Array [4].
Argument type: point is an Array [2], radius is an Array [2], postEffect is a Boolean, and t is a Number.
Samples the color and alpha channel values of a layer and returns the average alpha-weighted value of the pixels within the specified distance of the point as an array: [red, green, blue, alpha]. If postEffect is true, the sampled values are for the layer after masks and effects on that layer have been rendered; if postEffect is false, the sampled values are for the layer before masks and effects have been rendered. The input value point is in layer space; the point [0,0] is the center of the top-left pixel in the layer. The input value radius specifies the horizontal and vertical distance from the sample center to the edges of the sampled rectangle. The default value samples one pixel.Note: The postEffect parameter refers to effects applied directly to the layer, not to effects applied indirectly, such as with an adjustment layer.This example samples a rectangle 4 pixels wide and 3 pixels high, centered around a point 100 pixels down and to the right of the upper-left corner of the layer:
thisComp.layer(1).sampleImage([100, 100], [2, 1.5])
Dan Ebberts has an example of how to use the sampleImage method on his website: www.adobe.com/go/learn_ae_danobscuration.
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