Using PTEX with dynamically fracturing geometry

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So lately I have been playing around with fracturing and have run into the problem that anything UV related such as textures and fur can't work with dynamic fracturing. Instead you have to do the workaround of pre-fracturing geometry and using procedural shaders. However with the advent of PTEX I have been wondering if this could be the potential solution to this problem. So I just wanted to get some opinions on whether PTEX is a good option and how one would go about applying it to dynamic fracturing.
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I would say the opposite is true

UVs can pe preserved at least on outher shell of fractured geometry and additional uvs can be dynamically created on all cuts to map some tileable texture or you can still use rest attribute for procedural textures

PTEX however is highly dependent on polygon indexes, in other words on topology of your geometry, so if you change the topology, your PTEXture cannot be mapped correctly an therefore is completely useless. Since fracturing is changing the topology, I wouldn't bet on PTEX

your best choice is either Rest attribute or UVs
Tomas Slancik
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tamte
I would say the opposite is true

UVs can pe preserved at least on outher shell of fractured geometry and additional uvs can be dynamically created on all cuts to map some tileable texture or you can still use rest attribute for procedural textures

PTEX however is highly dependent on polygon indexes, in other words on topology of your geometry, so if you change the topology, your PTEXture cannot be mapped correctly an therefore is completely useless. Since fracturing is changing the topology, I wouldn't bet on PTEX

your best choice is either Rest attribute or UVs

Interesting. So what is the best way to preserve the UVs? All the times I've tried I never been able to pull it off.
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for preserving the UVs on outher shell all it takes is to have UVs created prior to fracturing

for creating UVs on inner parts though, you would probably need to dive inside Voronoi Fracture Solver in DOPs (inside of rigid body solver node) and change a few things there. Probably somewhere deep, where individual inner faces are created
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Interesting. Now does the fur tool use UV's then because I have tried using fur with fracture and even tried creating UV's before fracturing and the fur system went nuts. Maybe there is something about fur that I just don't understand. Any ideas?
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fur in Houdini doesn't use uv's for generating hair
it uses mostly Rest and Area attributes for stable hair distribution over animated geometry

so what you can do is ensure that both of this attributes are present before fracturing and turn off Set Rest Position in fur object
Distribution of the hair may still change when geometry is fractured, but you may be able to get away with it

Attachments:
fractured_fur_object.hip (2.5 MB)

Tomas Slancik
FX Supervisor
Method Studios, NY
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