• Adobe After Effects Expressions

  Looping an “if” expression

  Posted by Daniel Nye on November 18, 2019 at 12:56 pm

  Hi,

  I have two keyframes, one of which is controlled by a slider. That works perfectly.

  But I want the animation to loop back and forth, similar to the loopOut(“pingpong”) expression. Obviously if I put this at the end of the expression, it nullifies everything else.

  Does anyone know how I could get by this?

  if (numKeys > 1){
t1 = key(1).time;
t2 = key(2).time;
v1 = thisComp.layer("Slider").effect("value")("Slider");
v2 = 0;
linear(time,t1,t2,v1,v2);
}else
value

  Thank you!

  Daniel Nye replied 6 years, 6 months ago 2 Members · 2 Replies
• 2 Replies

• 

  Oleg Pirogov

  November 18, 2019 at 6:52 pm

  How about:
  if (numKeys > 1){
t1 = key(1).time;
t2 = key(2).time;
v1 = thisComp.layer("Slider").effect("value")("Slider");
v2 = 0;

  t = time<=t2 ? time : (Math.floor((time-t1)/(t2-t1)) % 2 === 0 ? t1+((time-t1) % (t2-t1)) : t2-((time-t1) % (t2-t1)));

  linear(t,t1,t2,v1,v2);
}else
value
• 

  Daniel Nye

  November 19, 2019 at 11:41 am

  Amazing, that works perfectly!

  Thanks.

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