Re: Expression to change value of keyframe

This version might be closer to what you're after. It fires a burst of particles at each slider keyframe and gets the birth rate value from the slider at the keyframe.


p = effect("Slider Control")("Slider");

n = 0;
if (p.numKeys > 0){
n = p.nearestKey(time).index;
if (p.key(n).time > time) n--;
}
if (n > 0 && Math.abs((p.key(n).time - time)/thisComp.frameDuration) < .25)
p.valueAtTime(p.key(n).time+.01)
else
0


Dan