Hi, I've some problems in using the cookie SOP in order to control the fractue of the wall. I've tried differents settings, and I don't manage to precisely cut the wall to make only the inner part breakable.
If someone could look at it, thx in advance.

Hello,

it isn't super clear what you want to do in this file. I'm assuming that you want to create some sort of fractured geometry that is similar to the shape of the ground geometry.

Using the cookie sop to do this is inadvisable for two reasons: 1)You're only going to get one piece that is either the union or intersection of the two geometries and 2) your ground plane is just a flat plane; the cookie SOP can't determine what is “inside” or “outside” of the intersection of two geometries when one of them is just a flat plane. If you make the ground plane a 3 dimensional shape, then you can use the cookie SOP, but it still wouldn't give you “fractured” geometry.

The easiest way to get fractured geometry is to use the voronoi fracture SOP, which takes geometry (the wall in your case) and points to use to create fracture pieces. The seed points determine where you get more fracture pieces, meaning that if you have a lot of seed points in one spot, you will get a lot of small fractured pieces there.

If you take a look at the HIP file I've attached, I used a sphere to place a bunch of points right above your ground plane. I then use those points as the seed points for the voronoi fracture SOP. This produces a lot of small pieces only above the ground.

You can then take this into DOPs and simulate the wall breaking apart, but that requires some further set-up.

Is this is what you want?

In fact, what I'm trying to get is something similar to the hip files files attached.
But for now, I'll try to stick to the voronoi sop. By the way, is there any equivalent to control the force constrain between each pieces, like in Realflow the Multi-joints?

May be this will help.