User Guide

413

ADOBE AFTER EFFECTS 5.0

User Guide

Motion Math scripts included with the Production Bundle

Several prewritten scripts, along with sample movies, are available from the After Effects

CD. Each script creates keyframes for speciﬁed properties and channels in one of two

layers, depending on the motion or effect you want. Most of the prewritten scripts create

new keyframes automatically, but you can use some scripts to change the values of existing

keyframes. By changing the scale factors or variable numerical values in the scripts, you

can achieve the effect you want. As you experiment with the prewritten scripts, you will

learn more about the Motion Math scripting language, and you will gain the conﬁdence

to create and save your own scripts. Scripts are named using a .mm extension.

The After Effects CD provides the following prewritten scripts and movies:

Apply from Effect Point (frmeffct.mm and frmeffct.mov) Copies the values of an effect

point from one layer, multiplies them by a scale factor, and then creates position keyframes

in a second layer using the new values.

Apply to Effect Point (toeffect.mm and toeffect.mov) Copies the horizontal or vertical (or

both) position values of one layer, multiplies them by a scale factor, and then creates

speciﬁed effect keyframes in a second layer using the new values.

Blink (blink.mm and blink.mov) Varies the opacity using the cosine function, cycling

through a speciﬁed range of opacity percentages, and then creates keyframes for the

speciﬁed layer’s opacity.

Comp Audio (cmpaud.mm and cmpaud.mov) Copies the values of the audio amplitude of

the combined audio for all layers in a composition, multiplies them by a speciﬁed scale

factor, and then creates keyframes for the speciﬁed property using the new values.

Copy Relative Values (parallax.mm and parallax.mov) Multiplies relative values of a

property in one layer by a scale factor and then copies them to a second layer.

Copy Values (copyvalu.mm and copuvalu.mov) Copies speciﬁed property values from

one layer, multiplies them by a scale factor, and then applies the new values to a second

layer. This script appears by default when you ﬁrst open the Motion Math window.

Double Spring (dbspring.mm and dbspring.mov) Simulates the motion of two objects

attached to the ends of a spring and creates position keyframes for both layers. If you have

created position keyframes for either layer before the start of the work area, the velocity of

each layer at the start of the work area is included with the motion of the layer.

UG.book Page 413 Wednesday, February 21, 2001 12:05 PM