Expressions and Scripting Flashcards
6 cards from real Adobe After Effects practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Expressions and Scripting flashcards as text
What is the difference between an After Effects 'Expression' and a 'Script'?
Answer: Expressions automate single property values per frame; Scripts run ExtendScript to control the entire application
Expressions live on individual properties and evaluate per frame; Scripts use Adobe ExtendScript (a JavaScript superset) to automate AE's full application object model.
What does `linear(t, tMin, tMax, value1, value2)` do in After Effects?
Answer: Linearly interpolates between value1 and value2 as t moves from tMin to tMax
linear() is a helper function that remaps an input range [tMin, tMax] to an output range [value1, value2], similar to a lerp function.
What does the `sourceRectAtTime()` method return for a text or shape layer?
Answer: The bounding box (top, left, width, height) of the layer's content at a given time
sourceRectAtTime() returns an object with top, left, width, and height values representing the layer's actual content bounds.
What does `posterizeTime(fps)` do in an After Effects expression?
Answer: Reduces the expression's evaluation to a specified lower frame rate, creating a choppy stutter effect
posterizeTime(fps) makes the property only update at the specified frame rate, creating a lower frame rate animation within a higher frame rate composition.
What does `comp('My Comp').layer('Layer Name').active` return in an expression?
Answer: A boolean true/false indicating whether the layer is currently visible and within its in/out points at the current time
The `.active` property returns true if the layer is enabled (eyeball on), not solo'd off, and within its in-out range at the current time.
What is the 'Expression Controls' effects category in After Effects used for?
Answer: Adding slider, angle, point, color, checkbox, and layer picker controls to a layer for use as expression targets
Expression Controls (Slider, Angle, Point, Color, Checkbox, Layer) act as custom control parameters that expressions can reference to drive other properties.