AE表達式
AE表達式
AK大神的網站VIDEO COPILOT ：http://videocopilot.net.cn/tutorials/
AK大神的網站下載：http://www.videocopilot.net/blog/2016/03/new-plug-in-saber-now-available-100-free/
1、Bounce&Overshoot
·Bounce 理解為“反彈”，如 皮球落地反彈的效果；
·Overshoot（過沖、夸張的）理解為“抖動”，如 果凍抖動的效果。
Keyframe Overshoot
freq = 3;
decay = 5;
n = 0;
if (numKeys > 0){
n = nearestKey(time).index;
if (key(n).time > time) n--;
}
if (n > 0){
t = time - key(n).time;
amp = velocityAtTime(key(n).time - .001);
w = freq*Math.PI*2;
value + amp*(Math.sin(t*w)/Math.exp(decay*t)/w);
}else
value
...........................
Keyframe Bounce Back
e = .7;
g = 5000;
nMax = 9;
n = 0;
if (numKeys > 0){
n = nearestKey(time).index;
if (key(n).time > time) n--;
}
if (n > 0){
t = time - key(n).time;
v = -velocityAtTime(key(n).time - .001)*e;
vl = length(v);
if (value instanceof Array){
vu = (vl > 0) ? normalize(v) : [0,0,0];
}else{
vu = (v < 0) ? -1 : 1;
}
tCur = 0;
segDur = 2*vl/g;
tNext = segDur;
nb = 1; // number of bounces
while (tNext < t && nb <= nMax){
vl *= e;
segDur *= e;
tCur = tNext;
tNext += segDur;
nb++
}
if(nb <= nMax){
delta = t - tCur;
value + vu*delta*(vl - g*delta/2);
}else{
value
}
}else value
