(Solved)POP: random drag per particle HELP

[gangland]

hello guys, i've an simple rain setup.

i would like to give them a little timming difence while they fall

i giving to each pop point an random value (using a pop vop).

when feeding into pop drag using and using an simple point vex expression it stand still.

any clue about??

thanks in advance.

cheers

ps: i attach an simple .hip file

point_randrag_V00.hip

Edited April 29, 2020 by gangland

[Noobini]

hey I don't know what I am doing here:

- in your popdrag, Inputs: Input1 Myself (still confused about this thing)

- set life to say 100, otherwise they 'stop' after about a second.

- should your popvop use id instead of ptnum ? dunno TBH.

[gangland]

32 minutes ago, Noobini said:

hey I don't know what I am doing here:

- in your popdrag, Inputs: Input1 Myself (still confused about this thing)

- set life to say 100, otherwise they 'stop' after about a second.

- should your popvop use id instead of ptnum ? dunno TBH.

hey, the life really do not matter, in the pop vop the particles are getting the random number like planned

the thing is in the pop drag, stil dkno to do

Edited April 29, 2020 by gangland

[Noobini]

well if you have life at 1, they stop, I just thought that looks weird, is all.

well did you set Input myself ? that works.

[gangland]

1 minute ago, Noobini said:

well if you have life at 1, they stop, I just thought that looks weird, is all.

well did you set Input myself ? that works.

yes they arent moving using the expression =//

[Noobini]

what's this then ?

[gangland]

14 minutes ago, Noobini said:

what's this then ?

the drag force of should by multiplied by a random number and i dont know how to do that

[Noobini]

oh yeah, i see what you mean now, sorry.

What I've noticed is if you use wind velocity in the drag to simulate gravity....it doesn't 'drag'

if however you reset wind to 0 and use gravity...the drag will work....randomly!!!

Edited April 29, 2020 by Noobini

[bunker]

you can create a varying f@mass for that:

f@mass=fit01(rand(@ptnum),chf("mass_min"),chf("mass_max"));

popmass_001.hiplc

[Noobini]

something smelly with the popdrag!!!

if you use a popwind in exactly the same way, -10, use VEX, same statement, and input Myself it works as expected.

[anim]

as bunker mentioned you can vary f@mass, alternatiely you can also vary  f@drag which will be automatically recognised

popdrag and popwind do the same thing, while popwind has just additional noise parameters so most of the times you are better off just placing popwind just in case you'll need the noise

here is example, based on your original file with f@drag varied, f@mass varied and popdrag and popwind  variations you can choose from and pick the setup that suits your preference

point_randrag_V00_mod.hip

Edited April 29, 2020 by anim

[Noobini]

5 minutes ago, anim said:

as bunker mentioned you can vary f@mass, alternatiely you can also vary  f@drag which will be automatically recognised

popdrag and popwind do the same thing, while popwind has just additional noise parameters so most of the times you are better off just placing popwind just in case you'll need the noise

here is example, based on your original file with f@drag varied, f@mass varied and popdrag and popwind  variations you can choose from and pick the setup that suits your preference

point_randrag_V00_mod.hip

you're just avoiding using popdrag which is the problem.

Use the orig file, with popdrag, with Use VEX option, doesn't work.

with popwind used in the same way as popdrag in all respects, it works.

[Noobini]

24 minutes ago, Noobini said:

you're just avoiding using popdrag which is the problem.

Use the orig file, with popdrag, with Use VEX option, doesn't work.

with popwind used in the same way as popdrag in all respects, it works.

I'll answer meself LOL...

I just tried the orig file with popdrag now...it works !!! what the ???

[anim]

40 minutes ago, Noobini said:

you're just avoiding using popdrag which is the problem.

what do you mean?

the file contains 4 versions, 2 of them use POP Drag, as I said, POP Wind has just noise on top, both modify the same attributes f@airresist and v@targetv

[Noobini]

well the OP used Use VEX option with the statement:

airresist = airresist * point(0, "rand_num",@id);

I cannot find that you use this anywhere in your scene. But I'm not here for a fight, you would pulverise me in a blink.

 

[anim]

25 minutes ago, Noobini said:

well the OP used Use VEX option with the statement:

airresist = airresist * point(0, "rand_num",@id);

right, that's however irrelevant for the distinction between popdrag and popwind and on top of that it's wrong

even with first input set to Myself, you can't read point attribute by just substituting point number with i@id, that's pretty random

so it would either be (first Myself) and:

airresist *= point(0, "rand_num",@ptnum);

but "rand_num" should be randomized using i@id

or you can for short use:

airresist *= f@rand_num;

and forget about Myself stuff

but anyway, point of that file was to show easier ways and not have to use drag/wind VEXpressions as there are already attributes that modulate drag for you

Edited April 29, 2020 by anim

[gangland]

10 hours ago, anim said:

as bunker mentioned you can vary f@mass, alternatiely you can also vary  f@drag which will be automatically recognised

popdrag and popwind do the same thing, while popwind has just additional noise parameters so most of the times you are better off just placing popwind just in case you'll need the noise

here is example, based on your original file with f@drag varied, f@mass varied and popdrag and popwind  variations you can choose from and pick the setup that suits your preference

point_randrag_V00_mod.hip

wow its cool to see difference approach for the same problem.

pretty clear!

thanks thomas