AE - Inertial Bounce

gistfile1.txt

bounces    = 1;     //total number of bounces
duration   = .5;   //duration of each bounce in seconds
amp        = 1.5;   //multiplier for incoming velocity used in bounce
decay      = 2;     //exponential decay of bounce height

n=0;
if(numKeys>0){n=nearestKey(time).index;if(key(n).time>time){n--;}}
n==0?t=0:t=time-key(n).time;
freq=1/duration;
mult = (bounces-Math.floor(t*freq))/bounces;
if (n>0 && mult>0) {
    v=velocityAtTime(key(n).time-0.001)*amp; //velocity to use
    b=Math.abs(Math.sin(freq*t*Math.PI))*Math.pow(mult,decay); //bounce calculation
    value-v*b;
} else {value;}