Adobe After Effects CS4 - Manual (Page 693)

687 USING AFTER EFFECTS CS4
Expressions
Last updated 12/21/2009
timeToStop = 4;
if (time > timeToStop){
value;
}else{
wiggle(3,25);
}
• Apply the following expression to a property to start wiggling it at time 2 seconds and stop wiggling it at time 4
seconds:
timeToStart = 2;
timeToStop = 4;
if ((time > timeToStart) && (time < timeToStop)){
wiggle(3,25);
}else{
value;
}
More Help topics
“ Add, edit, and remove expressions ” on page 647
Expression example: Match camera focal plane to another layer
❖ Apply the following expression to the Focus Distance property of a camera layer to have its focus distance match
the distance to the anchor point of a layer named “target”:
target = thisComp.layer("target");
V1 = target.toWorld(target.anchorPoint) - toWorld([0,0,0]);
V2 = toWorldVec([0,0,1]);
dot(V1,V2);
More Help topics
“ Add, edit, and remove expressions ” on page 647
“ Create a camera layer and change camera settings ” on page 186