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Boolean Fracture Pieces

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I am currently fracturing a simple wall using H16 new Boolean fracture. I noticed that the pieces it spits out are not actually a full pieces of geometry. Each chunk are missing the sides compared to the Voronoi fracture pieces. How do I get full geometry out of each chunk when using the Boolean method ?

Should I go into a foreach and bridge the sides ? There must be an easier way. 

I will attach some pictures and my file for anyone interested

Thank you




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Don't have time to examine your hip right away but you must be doing something wrong.

How are you creating your cut geometry? have you seen the Siggraph session?


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because you are treating your B as a surface.

Imagine a box, you treat it as a surface, cut it in half and you'll have 2 halves each with a missing side. Now if your box was treated as a solid,  then after your cut, you'll have 2 little cubes..

Now if you change your Boolean setup to Solid...it screws up.

A quick little test, if you put in a brand new box, treat it as solid, plug it in it works fine...so why does your original box not work...I suspect because it's been hollowed out but Boolean is trying to read it as a solid...and shat itself...

Now another little test...you chuck in a torus...topologically, it 'looks' like a hollowed out box right ? Plug that in, works fine....now I'm confused !!!

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Got it !!! you little bugger !!!

In your orig file, coupla steps:

01) the Boolean should treat B as solid...so that you don't get a missing side

02) step 1 would screw thing up as explain in prev post, now.....if you go back a bit, put display flag on Facet, turn on Display Prim Normals (below the display Point numbers button), you'll see the sides of the box correctly have magenta arrows pointing outwards...but the top/bottom are incorrectly pointing INSIDE the geometry. THIS is what screwing up the Boolean. So above the Facet, add a Reverse, now you'll see the top/bottom with arrows pointing outwards.

03) put Display flag back on the Explode...and voila !!!

ps: your box really should have more res than just a simple 1x1x1 segment....so you don't get artifacts..


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