• Adobe After Effects Expressions

  PI number animation

  Posted by Anthony Tonev on March 16, 2018 at 1:52 am

  Can someone re-create this in AE?

  https://upload.wikimedia.org/wikipedia/commons/2/2a/Pi-unrolled-720.gif

  If you unroll a circle 360 degrees you should end to 3.14 times its size. I’m not good at math but I thought I could make this with a simple expression in AE. The result was not the same… Now I feel even more dumb.

  For some reason I’m 1 integer off it seems. I get 2.14 or even 2.30 (not sure) if I position the circle at line 0 (like in the example gif). If I start from 1 instead of 0, then I think I might get 3.14 but that is not the right answer – it’s right if it starts from 0.

  Does someone know hot to make it work?

  Here are 3 stills from my result:

  https://images.creativecow.net/325455/comp1_00000.png
  https://images.creativecow.net/325455/comp1_00076.png
  https://images.creativecow.net/325455/comp1_00136.png

  Anthony Tonev replied 8 years, 2 months ago 2 Members · 2 Replies
• 2 Replies

• 

  Dan Ebberts

  March 16, 2018 at 6:30 am

  I’m not sure how you have things set up, but this position expression seems to work for a 100×100 solid:

  x = width*(rotation/360)*Math.PI;
  value + [x,0]

  Dan
• 

  Anthony Tonev

  March 16, 2018 at 9:47 am

  Thanks Dan – works great! I got it now.

Reply to this Discussion! Login or Sign Up