[After effects]-expression03

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var rot=15;
rot+=10;
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var rot=15;
rot ++;
rot ++;
rot ++;
rot ++;
rot ++;
rot;
//rot=20
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var rot=15;
rot --;
rot --;
rot --;
rot --;
rot --;
rot;
//rot=10
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var rot=15;
rot *=2
//rot=30
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var rot=15;
rot /=2
//rot=7.5
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var X=100;
var Y=0;
var seconds=Math.floor(time);
if (seconds !=1) Y=200;
[X,Y];
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var X=100;
var Y=0;
var seconds=Math.floor(time);
if (seconds ==0 || seconds==2) Y=200;
[X,Y];
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posterizeTime(10);//10 times per second
var randomNumber=random(48,122);
var myText=String.fromCharCode(randomNumber);
myText;
//ASCII code http://ja.wikipedia.org/wiki/ASCII

//String.fromCharCode(83)="S"
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w=wiggle(1,20);
[value[0],w[1]]
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----Set time and parent----
//position
pickuptime = 1;
dropofftime = 2; layertofollow = "bluestar"
ticker =Math.min(Math.max(pickuptime, time), dropofftime);
this_comp.layer(layertofollow).position.value_at_time(ticker)

//rotate
pickuptime = 1;
dropofftime = 2;
layertofollow = "bluestar";
ticker = Math.min(Math.max(pickuptime, time), dropofftime);
this_comp.layer(layertofollow).rotation.value_at_time(ticker)

----------------------------
Radius = effect("Radius")("スライダ");
Speed = effect("Speed")("スライダ");
RotationOffset = effect("Rotation Offset")("角度");

//

center = [this_comp.width/2,this_comp.height/2,0];
radius = 200;
angle = time * Speed + RotationOffset;
x = Radius * Math.cos(degreesToRadians(angle));
z = Radius * Math.sin(degreesToRadians(angle));
add(center, [x,z,0]);


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Radius = effect("Radius")("スライダ");
Speed = effect("Speed")("スライダ");
RotationOffset = effect("Rotation Offset")("角度");

//

center = [this_comp.width/2,this_comp.height/2,0];
radius = 200;
angle = time * Speed + RotationOffset;
x = Radius * Math.cos(degreesToRadians(angle));
z = Radius * Math.sin(degreesToRadians(angle));
add(center, [x,0,z]);
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---wiggle parameter---

wiggle(freq, amp, octaves = 1, amp_mult = .5, t = time)
=(freq, amp, how much extra detail, how crazy is the extradetail)
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var startPosition;
var endPosition;
seedRandom(1,true);
startPosition=random([thisComp.width,thisComp.height]);
endPosition=random([thisComp.width,thisComp.height]);
ease(time,0,5,startPosition,endPosition);
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var changeRate=1;
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var seedNumber=Math.floor(time/changeRate);
seedRandom(seedNumber,true);
random([0,0],[500,500])
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seedRandom(2,true);
random()
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str = "ABCDEFGHIJKLMNOPQRTSUVWXYZ";
str[timeToFrames(time)];
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L = thisComp.layer("star");
L.toComp(L.transform.anchorPoint)

L = thisComp.layer("source point");
L.toComp(L.anchorPoint)