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Forums Adobe After Effects Expressions How can I make some random velocity of each object with random position?

• # How can I make some random velocity of each object with random position?

2 Members · 2 Posts
• ### Byeong Han Kim

July 2, 2022 at 12:12 am

I try to make some falling objects, I can make random fixed position but I can’t make it move with random speed.

here is a expression that i try.

//

seedRandom(thisComp.layer(“Null 1”).effect(“rotation seed”)(“Slider”),true);

var x=[v,-v];//fixed y postition

var y=[-v,-v];//fixed y postition

gaussRandom(x,y)*(-time)*random(1,10)

//

actually it move it well but when i add //*(-time)*random(1,10)// this part to move it, position of objects are fixed at one position and then start to falling down.

can I get some any idea of this? I’m newbie of expression. So I want feedback of that poor expression too. Thanks.

sorry for my bad Eng ;<

• ### Filip Vandueren

July 8, 2022 at 9:40 am

Hi There,

it happens because you multiply by time, at the beginning time=0, so everything is [0,0].

You will probably need a random x,y position AND an random x,y velocity.

or multiply by (-time-1)

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