Smoke Emission from particles is funky, needs help!

[jwhit6142004]

Ok so here is my dilemma (one of many lately i know... Im very new to Houdini so please bare with me) I am trying to emit smoke from particles but as you can see from my video attachment, it looks as though the smoke is only emitting mostly from SOME particles and not the others, almost like smoke is choosing which particles to emit from and which ones not too. Also the smoke is going to mostly one side instead of equally spreading out. Maybe i forgot to do a step, but from all the tutorials ive watched i feel ive done every step. I feel very stuck I also am posting some pictures of my Location POP settings. As always, any help is greatly appreciated!

ParticlesTest_1.mov

[Guest tar]

should be easy to fix - can you upload your hip file please

[tmdag]

without hip file it is hard to say what might go wrong. You might have density values >0 only on certain particles or your volume box covers only that part of scene.

Edited November 4, 2013 by tmdag

[jwhit6142004]

test.hipnc

Sorry guys, heres my HIP file

[tmdag]

your velocity in the popnet is pointing specific direction (0.5, 1.5, 0.5) + small variance, and it is pushing most of smoke(points) there.

If you set velocity to (0,0,0) and add variance (5, 0, 5) it would be more randomly distributed in to every direction (X, Z) on plane.

Additionally in "Create_density_volume" sop, set density scale to higher value, like 10 so it will be easier to see what is going on.

Edited November 5, 2013 by tmdag

[jwhit6142004]

Thank you for the advice. Ill give that a try. My only complaint would be that would get me back to my old problem of how to make the particles move faster. I liked the initial movement but they werent moving fast enough. Is there another way to get that initial "blast" without changing the velocity?

[tmdag]

Velocity is reflecting your particle movement so if you would make particles move faster than your velocities will be much higher.

If you want to have blast, you can set higher variance lets say (30, 0, 30) and add drag to slower them down later on with higher scale than 1 for eg.6

if you want your particles to move fast but having low velocities values, you would have yo fake it in vops (for eg. you could multiply velocity vector magnitude by provided value).

Edited November 5, 2013 by tmdag

[jwhit6142004]

I guess i just dont understand why the smoke doesnt look like its emitting from each particle but rather just the origin point. If thats the case maybe i should just emit smoke from a sphere and skip the particles. Also im not to familar with VOP's yet. I would be totally lost.

[tmdag]

each voxel is sampling surrounding points within a distance (/obj/geo1/create_density_volume Scalar Volumes->Stamp Points->Sample Distance)

To see how it works,

- move to frame where you have points distributed on your scene for eg. frame 15.

- In /obj/geo1/create_density_volume in Scalar Volumes -> Settings tab make smaller division size, lets say 0.02 ( at this point it is controlled by DOP simulation but you can alter it for now)

- Increase your density for visualization - change Density scale from 1 to 100

- go to "stamp Ponts" tab and lowe Sample distance (lets say 0.2)

- As you see, still volume is not covering your points compleatly, that is because there is default noise turned on so go to tab nouse and turn it off

You should see volume spheres being created exactly on point poistions

[jwhit6142004]

ohhhhh ok cool. Ill play around with it later today and get back to you