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objuan
09-22-2016, 01:39 AM
I'm trying to use particles to make stinky odor lines coming up off of some objects. I have my objects emitting brown particles that drift up via positive Gravity with a little bit of Vibration and Explosion. I like it to start, but as it gets higher I want it to wave around and break up. I added a Null with a WindFX set to turbulence, which pretty much does what I want, except it seems like it only does it on 1 plane, as defined by the Turbulence Vector.

I want my particles to roll around Turbulence Fields in all 3 dimensions, how do I get that set up?

(I seem to recall having similar issues with some of the distort plugins in the past, only doing 1 dimension at a time.) If I put a turbulence texture on a surface, it is a 3d field that intersects wherever my model is in 3d space. Can't I do that same thing but have particles be swirled by it? (or geometry displaced?)

prometheus
09-22-2016, 09:36 AM
not necessary to add a null then add windfx on it, you can go to dynamics tab and add dynamic wind instead,make sure to check your falloff mode, if you turn it off..it should effect infinity..you may have to small radius, or you may have scaled the wind force to small.
Then you have the vector fields, by default only turbulent size has all values active, the others (turbulent vector and wind) has their z depth zeroed out..so you may need to set something there, click on play and tweak some of those values so you can see it.

a tip..etc tab of the wind force, set the draw style to detail, and crank up the grid values from 8 to 20 perhaps and you will get guide representing vector field influence.

I would also consider take a look at the vortex force instead, and also maintain gravity as it was and instead raise the particles velocity up instead of negative gravity, you can also push particles with textures if you add a directional wind and enter the texture buttons of winds vector(the fields x, y, z) this may however be slow if you got to many particles.

prometheus
09-22-2016, 09:49 AM
I must add, turbulence wind force has that none full 3d effect, itīs really not that good, I prefer to add a procedural ripple texture and use a directional wind instead, but it can be slow, and for a bit more random look you should even use two procedural textures, first ripple then another like turbulence on top of it to add variations.

objuan
09-24-2016, 01:06 PM
Thanks. Hopefully you need not spend any time having your liver eaten by a vulture as service for helping me (us) get this smoke started...

MonroePoteet
09-24-2016, 05:21 PM
You might have some success by rotating the Turbulence Wind object over time so it's Vector changes over time, having it's Falloff set to Distance of say 2m, power of 200%, and setting it 2.5m above the Emitter so the particles aren't affected until they're .5m off the ground (or whatever). Sample scene attached, with HV Size, Density and Opacity all controlled by a Gradient on Particle Age.

Good luck!
mTp

jwiede
09-24-2016, 07:23 PM
I must add, turbulence wind force has that none full 3d effect, itīs really not that good, I prefer to add a procedural ripple texture and use a directional wind instead, but it can be slow, and for a bit more random look you should even use two procedural textures, first ripple then another like turbulence on top of it to add variations.

I understand why it might be desirable in this special case, but in general it seems more "usable" for wind turbulence to behave as it does, with a single dominant vector and minor order variations to that vector -- in doing so, "turbulence" is actually more usable/realistic w.r.t. "how wind works". I'd be fine if they wanted to add another "roiling"/"churning" effect which did the "full 3D effect" you're describing, but I don't think replacing the existing "turbulence" behavior with that "full 3D effect" (basically a randomized, dynamic vector field of air) is a good idea.

prometheus
09-24-2016, 08:50 PM
I understand why it might be desirable in this special case, but in general it seems more "usable" for wind turbulence to behave as it does, with a single dominant vector and minor order variations to that vector -- in doing so, "turbulence" is actually more usable/realistic w.r.t. "how wind works". I'd be fine if they wanted to add another "roiling"/"churning" effect which did the "full 3D effect" you're describing, but I don't think replacing the existing "turbulence" behavior with that "full 3D effect" (basically a randomized, dynamic vector field of air) is a good idea.

Quite pointless to speculate, neither you or I know exactly the look objuan is aiming for.
what we do know is that the flat turbulence look is not what he wanted.. and what I suggested can help get a more fuller 3d look in the turbulence.
Why isnīt it a good idea? are you so sure of what type of look he is aiming for?

By the way...there isnīt much wind in a closed home, or room....yet you will see smoke or steam boil up with tremendous vorticle behavior, and that is not a job for the standard turbulence field, and if this is stinky odour ..I suspect it may be closer to smoke, rather than leafs or dust in a wind etc.



https://www.youtube.com/watch?v=8AUguci1lPY

jwiede
09-27-2016, 02:54 PM
Quite pointless to speculate, neither you or I know exactly the look objuan is aiming for.
what we do know is that the flat turbulence look is not what he wanted.. and what I suggested can help get a more fuller 3d look in the turbulence.
Why isnīt it a good idea? are you so sure of what type of look he is aiming for?

You didn't actually read what I said, did you? :devil:

I didn't say the things you're suggesting I did. I said replacing the existing definition with another would be undesirable.

prometheus
09-27-2016, 05:28 PM
You didn't actually read what I said, did you? :devil:

I didn't say the things you're suggesting I did. I said replacing the existing definition with another would be undesirable.

No...I did read what you wrote.
Understanding you right or wrong is a different thing though:D and understanding you right is probably something I havenīt done here.