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Random position a square in a range of values for a specific amount of time

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Hassan Ganari
Random position a square in a range of values for a specific amount of time
on Aug 17, 2019 at 4:49:41 pm

Hi guys,

I have 1000x1000px comp with 10sec duration, and a 200x200px square layer.
I want the square to show up in EVERY 2 seconds (fade in then out) but every time in a different position, i need that position to be picked random from a range of values.

range = ([0,0],[0,200],[200,0],[0,400],[400,0],[0,600])

I am scratching my head for hours in vain.
the closest i got was in this link https://forums.adobe.com/thread/2317002

This needs to be an expression, not a script please.

Thank you very very much.


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Dan Ebberts
Re: Random position a square in a range of values for a specific amount of time
on Aug 17, 2019 at 7:22:37 pm

try these:


// opacity

fadeTime = .5;
period = 2;
t = time%period;
if (t < period/2)
ease(t,0,fadeTime,0,value)
else
ease(t,period-fadeTime,period,value,0)


//position

period = 2;
seed = Math.floor(time/period);
positions = [[0,0],[0,200],[200,0],[0,400],[400,0],[0,600]];
seedRandom(seed,true);
i = Math.floor(random(positions.length));
positions[i];



Dan



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Hassan Ganari
Re: Random position a square in a range of values for a specific amount of time
on Aug 17, 2019 at 9:23:58 pm

Thank you so much Dan,

that worked !

Now I got that problem when I hit play, the same pattern of position is repeated, so i tried to put a slider control and inject it in the seedRandom but i clearly miss the syntax and the algorythm !


Thank you again for your help, it's sooooOO cool ^^


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Dan Ebberts
Re: Random position a square in a range of values for a specific amount of time
on Aug 17, 2019 at 11:13:23 pm

I'm not sure I understand what issue is. You shouldn't get a repeating pattern.


Dan



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