Volume Velocity to Mesh?

[ParticleSkull]

Hey guys, I'm growing some objects using volumes (scene is attached) and I'd like to have motion blur on the moving/growing areas.

I do have some velocity on the volume, in order to control it's growing direction, but i have no idea on how to transfer it to the mesh itself.

here's how the setup looks like:

Thx

Volume.Growth.Velocity.v1a.hiplc

[animatrix]

You can use Attribute From Volume SOP.

 

[ParticleSkull]

Wow, never heard of it

Will check it right now, thx!

[Deviner]

HI, I think it's possible to sample velocity from volume with "Volume Sample Vector" vop or with volume wrangle
smtn like this v@v = volumesamplev(1, "vel", @P);
must be faster than attrib from volume

Edited July 5, 2017 by Deviner

[ParticleSkull]

Thx @Deviner! The Attribute from Volume did transfered that velocity to the mesh but doesn't work as I expected (for some obvious reasons the static part of the mesh was getting velocity as well)
I can't test what said right now but i'll do it first thing in the morning. Thx man

Cheers,
Alvaro

Volume.Growth.Velocity.v1b.hiplc

[Nebucadnezar]

Hello ParticleSkull,

 

   You can use what @Deviner said and  build a mask to ensure that only the moving part will get the velocity :

 

- To buid the mask you can use on one side your original geo and color it white with a color node and then on another side timeshift one frame back your geo and color it black. You can then use an attribute transfer from the black (your mesh with one frame back) to the white (your original mesh) so only the new growing points will be white from frame to frame.

 

- then just use an if statement to transfer your velocity :

if(@Cd.x>0.1)

{

v@v = volumesamplev(1, "vel", @P);

}

else

{

v@v={0,0,0};

}

 

 

[ParticleSkull]

Cool,  Guerton! I'll give it a try asap

[Atom]

For motion blur just drop down a Trail inside of geo1, right after you rename vel to v, to compute velocity. You can scale it as well at that point.

 

Edited July 18, 2017 by Atom