randomized motion path with given start and end position

[Dan Ebberts]

This probably isn’t exactly what you have in mind, but it might get you started. It’s designed for a bubble field, where you create one bubble and then duplicate the layer a bunch of times. Each time trough, a layer gets a different path. It’s set up to start with each layer already on screen, but if you don’t want that, just set prerun to zero.

minWobble = 10;
maxWobble = 25;
minLife = 2;
maxLife = 3;
minFreq = .5;
maxFreq =1;

seedRandom(index,true);
life = random(minLife,maxLife);
prerun = random(maxLife);

t = (time-inPoint+prerun)%life;
seedRandom(Math.floor((time-inPoint+prerun)/life),true);
wobble = random(minWobble,maxWobble);
freq = random(minFreq,maxFreq);
phase = random(Math.PI*2);
xBase = random(wobble + width/2,thisComp.width-wobble-width/2);
x = xBase + wobble*Math.sin(t*freq*Math.PI*2 + phase);
y = linear(t,0,life,thisComp.height+height/2,-height/2);
[x,y]

Dan

[Patrick Grossien]

You’re the best! Thanks a ton. This looks like I might get it to work the way I want. I’ll take some time to test it out and will report back.

You’re amazing! Thank you 🙂

[Patrick Grossien]

Thanks again Dan, I dropped a little thank you tip in your jar! 🙂

I got this to work the way I wanted it to. Even though I had a little bit of trouble getting the frequency correct, because I wanted a max amount of 2 curves per path and therefore it needed to be linked to the life span / speed of the bubbles.

Through trial and error I got that timing to work with the following, doing the same thing for the min and max values.

(minLife is at 30 at the moment)
minFreq = (minLife/720)


I was trying something along the lines of
minFreq = (minLife/(minLife*60));

which didn’t work exactly how I want it

Maybe you can unravel for me how frequency in connection to time could be calculated, so that a variable can be set to the amount of peaks the bubble is doing per path and not the amount per sec as freq. is doing it now.

Best,
Patrick

[Patrick Grossien]


minLife = 30
peak = 6
minFreq = minLife/(minLife*(24/peak));


this seems to be working somewhat – but why 24? 😀
and what would be truly accurate?

I’ll then create a maxPeak and minPeak to add to the code for easier control.

[Dan Ebberts]

If you want to tie the frequency to the life, I’d do something like this:

minWobble = 25;
maxWobble = 50;
minLife = 10;
maxLife = 15;

seedRandom(index,true);
life = random(minLife,maxLife);
minPeriod = life/2;
maxPeriod = life/1.5;
period = random(minPeriod,maxPeriod);
freq = 1/period;
prerun = random(maxLife);

t = (time-inPoint+prerun)%life;
seedRandom(Math.floor((time-inPoint+prerun)/life),true);
wobble = random(minWobble,maxWobble);
d = thisComp.height + height;
phase = random(Math.PI*2);
xBase = random(wobble + width/2,thisComp.width-wobble-width/2);
x = xBase + wobble*Math.sin(t*freq*Math.PI*2 + phase);
y = linear(t,0,life,thisComp.height+height/2,-height/2);
[x,y]

Dan

[Patrick Grossien]

Thank you, Dan.

Is there a reason, that “d” isn’t used after being defined?

[Dan Ebberts]

No, I started down one path, but ended up going a different way.

Dan

[Joey Harvey]

I’m writing here as the subject title is exactly what I think I’m looking for but I don’t think the solution is quite suitable for my needs
(unless I’m misinterpreting how to adapt it).

I have a shape layer that has an exact start position. I want the shape to move around my composition in a classic motionscript.com ‘random motion – more chaotic’ manner then at a given time proceed to an exact end position.

I have managed to get a layer to start and stop moving when I want it to, but not been able to wrangle the layer to the correct start and stop positions.

Could anyone help put me on the right path?

[David Cabestany]

Maybe I’m oversimplifying things or just didn’t understand what you need but, can’t you achieve this by adding a wiggle expression to your object and then parent it to a null with the arc animation?