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USING FLASH CS4 PROFESSIONAL
Timelines and Animation
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To link associated pairs of X and Y properties, click the Link X and Y Property Values button for either one of the
properties you want to link. When the properties are linked, their values are constrained so the ratio between them
is preserved when you enter a value for either of the linked properties. Examples of associated X and Y properties
include the Scale X and Scale Y properties and the Blur X and Blur Y properties of the Drop Shadow filter.
Easing tweens
Easing is a technique for modifying the way that Flash calculates the property values in between property keyframes
in a tween. Without easing, Flash calculates these values so that the change to the value is the same in each frame. With
easing, you can adjust the rate of change to the values for more natural or more complex animation.
An ease is a mathematical curve that is applied to the property values of a tween. The final effect of the tween is the
result of the combination of the range of property values in the tween and the ease curve.
For example, if you animate a picture of a car across the Stage, the motion is more realistic if the car starts from a stop
and slowly gains speed and then slowly comes to a stop at the other side of the Stage. Without easing, the car would go
from a stop to full speed instantly and then stop instantly at the other side of the Stage. With easing, you can apply a
motion tween to the car and then make that tween start and end slowly.
A motion path with no ease applied. Note the even distribution of frames along the path.
Updated 5 March 2009
