pop grains following a deforming mesh

[pau22]

Hello,

 

I would like to know if that approach is possible using PDB and the new grain solver:

 

1. Create a Granular solid from a VDB animated mesh and make all the grains move acording to its deformation and position.

 

2. Break some of the constrains so that some particles will no longer follow the VDB mesh.

 

 

Thank you!

Edited April 7, 2016 by pau22

[Ryan]

You can use the pointDeform SOP to set a rest position on your grains. In DOPs have position equal to rest until you want them to fall off.

point_deform_grains.hip

[fathom]

grains can be pretty unstable when they intersect with each other.  deforming would very likely lead to loads of particle intersections.  you'd probably have to adjust radii to avoid intersections prior to activation...

[pau22]

Thanks!

 

The points are sticking pretty well to the mesh!

 

Now I will have to figure out how make the sim stable and the pop source update the grain position each frame

[Ryan]

Here is what I was thinking you could do in DOPs.

 

Use a popwrangle, popvop, or sopsolver to get the rest value (the animated position).

Then animate the "activation" any way you want in SOPs. When the particle is activated, dont use the rest anymore.

point_deform_grains_v02.hip

[pau22]

Here is what I was thinking you could do in DOPs.

 

Use a popwrangle, popvop, or sopsolver to get the rest value (the animated position).

Then animate the "activation" any way you want in SOPs. When the particle is activated, dont use the rest anymore.

 

Thanks Ryan, that's awesome! it works really well.

 

You've made my day!