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emission rate vs position variation

Posted: Tue Nov 26, 2013 8:55 pm
by jesse nicodemus
Hello

I have a question about @ position variation, specifically the way higher values also increase the number of particles. Would it be possible to have control over how many extra points are being added?

The way I am currently using the setting I need to turn position variation to 0. If I turn the value to .2(that is roughly where I would need it to be useful) I go from 10,000 to millions with a very spotty layout. High @emission rate gives me a better spread per cubic meter but at my scale any @position variation value high enough to be useful spikes my count more then I want. It would be nice if I could pick to add only 2 or 3 particles inside a radius so that I could more effectively use both settings.

Jesse

Re: emission rate vs position variation

Posted: Wed Nov 27, 2013 5:17 pm
by LuisMiguel
Hi Jesse,

Just for info. I usually change this value between 0.1 and 0.07. If you have a lot of particles with 0.1, you could set a value of 0.08 or 0.085 to get less particles.

luisM.

Re: emission rate vs position variation

Posted: Wed Nov 27, 2013 6:42 pm
by atena
The reason why this is done this way is because when you change the "Type" from "Dumb" to "Liquid" for your splash emitters the amount of particles that can be introduced per volume unit has to be computed in such a way that the SPH simulation is stable.

It is true that when the "Type" is "Dumb" we don't have that constraint so maybe another more controllable way of seeding particles would be better.

You know that the points used to trigger the generation of splash or foam are the position of the core particles, having a big amount of core particles will allow you to sample better for splash and foam emission and will allow you to reduce the position variation to avoid the spotty layout.

Re: emission rate vs position variation

Posted: Wed Nov 27, 2013 7:53 pm
by jesse nicodemus
Thank you for the information. I did find that cranking the emission rate had really good results with a relatively low hit on sim time.