Help with breaking selective pieces of geometry and more...

[Akabane]

Yo there.

I started to do some learning projects in houdini, and one of them is an infesting terrain...basically, it is a terrain with an infestation spreading.

Here is what i have so far:

That's simple - I attributeTransfer Cd from some particles on top of the terrain on the terrain itself, grouping the infested points and using them to move and modify the infested parts.

Now what i want to achieve is to have the infested part of the terrain to shatter - ideally i'd like to use the shatter sop, since i don't need all the bells and whistles created by the break node (later in the post i'll explain why).

So i did an attributePromote to convert the infested points to primitives.

The problem is that when i do that and append either the shatter or break sop, and insert the primitive group to shatter, nothing happens. It seems like they only work with the whole geometry, and that seems strange to me.

Nor the points group or primitive group work.

To cheat a little, first of all i deleted all the non infested group and then used a shatter sop on those, so that i didn't have to use a selective group on the shatter node.

The problem i see here is that the shatter sop tries to "adapt" itself on the geometry, wich changes in time, so i don't have a fixed shatter that expands, and that is what i need.

Like a "mask" for the shatter.

That's because, after doing that, i'd like to shrink a little the single pieces created by the shatter and extrude them with various values (maybe with a foreach sop?) obtaining the effect of a breaking terrain.

So, after all this chat, is there a way i can do that? I mean, the "masking" for the shatter to make it not modify with the changing mesh.

Oh, and a last thing then: what if i want a particle to move only inside the infested part of my terrain?

Thanks for reading!

Hope i will get some help on this!

Akabane