FORUMS: list search recent posts

Move in an arc motion from one position to another

COW Forums : Adobe After Effects Expressions

<< PREVIOUS   •   FAQ   •   VIEW ALL   •   PRINT   •   NEXT >>
Jon Date
Move in an arc motion from one position to another
on Sep 29, 2013 at 3:05:35 pm

I've been trying to get a layer to move from one position to another position in a semi circle motion. Does any one have any tips for this? For example I have a layer at 100,100 in x,y and the second position is at 1300,1300. I would like the an expression that moves the layer from point A to point B in an arc motion over a period of time. The reason why I don't just use a motion path is because the second,and then third, fourth position will be random. Any ideas would be very much appreciated.


Return to posts index

Dan Ebberts
Re: Move in an arc motion from one position to another
on Sep 29, 2013 at 11:57:39 pm

It depends on the details, but it could look like this:

p1 = [100,100];
p2 = [1300,1300];
dur = 1;

center = (p1+p2)/2;
r = length(p1,p2)/2;
p0 = p1-center;
a0 = Math.atan2(p0[1],p0[0]);
a = a0 + linear(time,inPoint,inPoint + dur,0,Math.PI);
center + [Math.cos(a),Math.sin(a)]*r;


Dan



Return to posts index

Jon Date
Re: Move in an arc motion from one position to another
on Sep 30, 2013 at 7:56:27 pm

Thank you Dan, thats perfect! I'm going to try and understand the math behind it for future use.
Cheers


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]