Forums Technical Discussion RBD Material Fracture Distorts UV's [SOLVED]

RBD Material Fracture Distorts UV's [SOLVED]

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Midphase
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Hello guys,

I'm a bit stumped by this. Basically I have a piece of stained glass that I'm fracturing by throwing a brick through it. I'm using a UVTexture node with a Perpective from Camera to create my UV's.

Unfortunately while everything looks fine when the glass is pre-fractured, the moment I instance the RBDMaterialFracture node to create my glass fractures, my UV's (and image) become distorted.

I can't figure out how to get my projected image to look correct….any ideas?
Edited by Midphase - July 30, 2020 20:06:07

Attachments:
SOTS_SHOT_1_v3_3Delight1_0001.jpg (1006.9 KB)
SOTS_SHOT_1_v3_3Delight1_0001 2.jpg (1007.0 KB)
RBD_UVs.hiplc (1.2 MB)

>>Kays
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mikhail s
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Hey,
Just out of curiosity why not to project UVs after the pieces are fractured?
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Midphase
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Because then this happens:

Attachments:
RBD_UVs_3Delight1_0001.jpg (1.1 MB)

>>Kays
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https://www.youtube.com/c/RightBrainedTutorials [www.youtube.com]
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lewis_T
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The UVs are fine. Just unpack the high-res geo, and you can see they are present and correct.
It could be an issue of packed geo not being unpacked during render correctly maybe.
I'm not lying, I'm writing fiction with my mouth.
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Midphase
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I just tested in Mantra and I get the same distorted results. I don't think this is a 3Delight bug.
>>Kays
For my Houdini tutorials and more visit:
https://www.youtube.com/c/RightBrainedTutorials [www.youtube.com]
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jsmack
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what's wrong with it?

seems okay for me, accounting for the fact that perspective projections will be distorted due to their non-linearity.

Attachments:
fracturedproject.hip (290.9 KB)

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Midphase
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Ok, thanks to TinyHawkus' help I think the issue is solved.

Basically the two things that made a difference were to use a PolygonMesh for my stained glass geometry as opposed to a simply Polygon, and then place the UVTexture node immediately after the RBDMaterialFracture.

This yields an 100% match to the footage plate.

Thanks everyone!!!

For those curious, here's what my final node tree looks like:

Attachments:
Screen Shot 2020-07-30 at 4.40.55 PM.png (104.8 KB)

>>Kays
For my Houdini tutorials and more visit:
https://www.youtube.com/c/RightBrainedTutorials [www.youtube.com]
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