rendering fractured geometry

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me again
when I render this fractured model it looks like normals on pieces are mess… and I get ugly black shadows close to the edges.. I guess it's because of normals and not so nice topology.
Is there a way to fix that in houdini?

thanks.

dj.

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ok. I manage to make it a little bit better with facet sop… but still not nice enough..
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I think typically people swap out fractured and non fractured geometry to compensate for this.
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The typical workflow for a situation like that is to store the pre-cut normals, and blend them back to the post-cut normals as the pieces break of.

(1) create base geo
(2) cut the base geo's surface (do NOT adjust normals)
(3) store normals.
(4) generate internal slices of chunks
(4) copy normals from step2 into N
(5) animate your pieces falling
(6) blend restN into deforming N as pieces move from their rest (intact) position.

G
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in the help examples i saw something related to Fracture an Object when it hit something and depending on the force is the trigger, to fracture or shatter the object.
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jesta
I think typically people swap out fractured and non fractured geometry to compensate for this.

That's what I do. Change the visibility as soon as the fractured geometry gets hit. Very helpful for glass.
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i know in houdini is posible to set it up on the dynamic network, not sure how but is posible,
(we do it on the old way manualy keyframe it)
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visibility on and of is the solution for the moment I think,
thanks for the help

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I think an attribute transfer of the normals between the original model and the fractured one should do the trick, did you try this?

Koen
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ops: how to transfer normals?
models are objs imported from maya.
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AttribTransfer SOP.
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This will only work if you model is perfectly still, in the pose it was created.

Something quite rare I find.

G
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