Speed By size

[cabra]

Hello everyone

I am very newy...., spent much time learning every day.

I wish someone would kindly explain how to handle the speed of certain particles depending on size. Although I fail to grasp the whole thing, some words could help me, I'm using 3d max for over 10 years and I want rid of the bars.

Thank youuuuuu

[TheUsualAlex]

hello. welcome to the forum.

well, there's a couple of things you can try. One of them is, if you're using an attribute (such as pscale or width) to determine the size of your copied object, you can simply use this attribute to multiply your particle velocity (or acceleration). If you simply have several geometry that's literally big and small, you can either use an approximated number until it looked right. Or, you can use Measure SOP to measure the volume (slow) or area of the geometry to multiply against the velocity of your particles. Please note that when using MeasureSOP to measure the area, you may have to use AttribPromote to get the sum of all your area for your entire geometry (summed into Detail attribute).

Hopefully this makes sense........ let us know if not.

Have fun!

[anim]

you probably want to change "mass" attribute of the particles according to "pscale"

then forces should use that mass to calculate acceleration and therefore produce different velocities depending on scale

[cabra]

as soon as I read what you both said I understood and gave me a lot of sense light at all. Theusualalex,Anim. THanKs!