pyro clustering velocity

[isah_voodoo]

hello

I have a big problem with my pyro clustering setup.

I am trying to pump some custom velocity in my smoke trail but nothing is happening.

I have a basic animation of a ball moving across the screen and I used the smoke trail shelf tool to make the basic clustering network

I noticed even when I bring in collision, I am not able to increase the velocity of the collision.

I hope someone can shine some light on why this is happening. 

I'll attach my scene file for anyone that wants to take a look .

Thank you.

[isah_voodoo]

here is the file

clustering_vel.hip

[devilchu]

hello,

for your velocity to be active in the clustering set up, you need to transfer the cluster attribut on your points velocities,

and after what you can do is duplicate the for each loop used for density and temperature.

Put it directly after your attribut transfer, rasterize attribut v only, and make it your OUT_v (it should give you a grid name like that v_1...)

 

 

Edited August 27, 2019 by devilchu

[isah_voodoo]

@devilchu

Thank you, that works.

Not sure why the velocity works though. If it is naming the v attribute to v_1 ,v_2, v_3 , etc. than how is dops renaming that to vel ? In the source volume inside dops it take a v attribute and remaps it to vel. How does it know that v_1, v_2 is the attribute v ??

I managed to bring in my collision using the deforming object shelf tool ... but I'm trying to figure out how would I get my collision to work  if I wanted to use the "collision" preset under initialize in the volume source in dops ?

appreciate the help

[devilchu]

How does it know that v_1, v_2 is the attribute v ??

Check the instancing tab, instancing details on the volume source, it explains how it is working like that.

For your collision, if you want to source it, you should create a vdb from polygon directly after the trail of your collider,

make it 2 grids, surface VDB should be name collision and add an attribut point.v which is by default is name v.

This is your OUT_collider,

then source it in the dop network and use the preset collision, be careful to put instancing Off just on this one.

You can enable the visualization of collision on the smoke object.

 

Edited August 28, 2019 by devilchu

[MadMax50]

.

Edited September 2, 2019 by MadMax50

[isah_voodoo]

 @devilchuThank you . I get it now. Turning off the instancing was exactly what I was looking for to make the collision work. Thanks !