Voronoi for Boolean?

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I want to break off the other 'shell' of a building using a voronoi pattern. However, while the end result kinda works it is very unstable and error prone. Maybe someone here has a better approach. Here is what I am doing:

1. I select the prims and apply a voronoi. I cluster the pieces into larger groups. At this time this is only a surface as I have no insides.

2. I delete all other clusters but one random one.

3. I extrude the cluster along primitive / egde normal. Here the biggest problem occurs - depending on the complexity of the voronoi, if I extrude it too much I get intersections which cause problems in the next step.

4. I use a Boolean SOP to substract the extruded cluster from my original building. This example looks fine, but as you can imagine, if I have intersections with the cluster the whole boolean goes bonkers. Any recommendations for a different, more flexible and stable approach?

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art3mis    31

I'm no expert but pretty sure that you shouldn't be extruding AFTER any sort of voroni or boolean fracture-shatter operation. I'm guessing some combination of tetrahedralizing + boolean and followed by boolean shatter? but other experts should chime in...

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Atom    516
Posted (edited)

What if you extrude the main structure before you fracture?

Then all the resulting pieces will fit together nicely.

Edited by Atom

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Atom    516
Posted (edited)

Playing around with extending this so you can get a set of primitives separated from the host shape. Then you could boolean those against the original. The group scatter point selection is linked to a group primitive delete via relative expressions.

Edited by Atom

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Hey that's a cool approach. Have you actually tried to bool substract the voronoi from the original box? While the initial extrude could solve a lot of problems (so simple, so good!) one of the stupid problems remain - the outer prims of the voronoi match the position of the outer prims on the box, and in some instances they will not bool properly, leaving a shell in some areas. A way to fix this is to add an additional extrude in the opposite direction to not only substract inside the box but to add some safety check to the boolean, but I feel this is not a very clean approach. I'll try some more and keep reporting, you seem to be interested in this as well ;-)

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Noobini    82

easy peasy....lemon squeezy..

In my setup...first, you'll see artifacts with the Boolean in the top right corner...there's slivers and isolated verts floating around...nasty.

Now the magic ingredient, enable the Fuse...poof...all artifacts gone...
There was no need to extrude anything, the Boolean treats both A and B as surfaces.

Voronoi_Boolean.hipnc