Reversing an animation?

[Walter Soyka]

[Ilia Kotchen] “I have an object animating along a path. It animates from the first point to the last point as it should. My question is: Without redrawing the path in reverse, how can I make that object follow along the path from the last point to the first point instead?”

Alt+click the position stopwatch for the item you wish to reverse, and enter the following expression:

// expression to reverse keyframe evaluation in time
// i.e., the first keyframe will be used last, and the last will be used first
// everything in between will also be reversed, because we will essentially run
// time backwards in this property only

// we need 2 or more keyframes on the property to be able to reverse them
if (numKeys > 1) {

// We're going to look at the current time, then figure out where it is in relation to the range of time
// from the first keyframe to the last. We will store in t the interpolation of what that value would be
// if that exact range of time were reversed, running backwards from the last frame to the first
t = linear(time, key(1).time,key(numKeys).time,key(numKeys).time,key(1).time);

// get the value of the property at the reversed time
valueAtTime(t);
} else value // if we have less than 2 keyframes, just return the underlying value

Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
@keenlive   |   RenderBreak [blog]   |   Profile [LinkedIn]

[John Cuevas]

Not sure if this will help, but thought I would toss it out here, ReverseMaskPath

Johnny Cuevas, Editor
Thinkck.com

“I have not failed 700 times. I have succeeded in proving that those 700 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work.”
—THOMAS EDISON on inventing the light bulb.

[Elnaz Johnson]

great solution!!!
Is it possible to select keyframes and right-click on them and then select reverse keyframes ?
does this solution works ?

I found a website that contains After Effects Template for download:
https://www.digiphic.com