Hello,
I was changing the geometry obj loaded in houdini geometry node for the groom, the topology is the same, but shape is different.
The guides generated in the guide groom mode appear to follow this changed shape without issue but the hair generation node then shows big bald spots with no hairs in parts of the groom. Is there a workflow that allows us to change geometry once guides have been created within the guide groom node that will propagate to the hair generation node as expected?
Best,
Erin
Change underlying model geometry for character groom
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- SWest
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Thanks SWEST,
The file is on our secure network, it's commercial work for tv, so there isn't a way for me to share it. I'm learning on the job in the absence of any training and support so it's fun but a bit frustrating when things start going wrong.
It certainly took a while to figure out why every tutorial on hair on youtube was different than what I was seeing with the new tools in 19. The results are fantastic though!
The file is on our secure network, it's commercial work for tv, so there isn't a way for me to share it. I'm learning on the job in the absence of any training and support so it's fun but a bit frustrating when things start going wrong.
It certainly took a while to figure out why every tutorial on hair on youtube was different than what I was seeing with the new tools in 19. The results are fantastic though!
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- toonafish
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Here's a basic scene with a shape that deforms a hairy torus, looks like it could work if you have a a similar setup:
https://www.dropbox.com/s/pzbwspzmd9um60n/HairShapeDeform_01.hiplc?dl=0 [www.dropbox.com]
https://www.dropbox.com/s/pzbwspzmd9um60n/HairShapeDeform_01.hiplc?dl=0 [www.dropbox.com]
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- toonafish
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Funny, now I'm running into similar issues.
I have to adjust the head geometry after I edited a hair groom, but when I replace the head geo the hair groom does not move with the shape of the new geometry. It sticks to the old groom topology, essentially the same problem as what is mentioned at the start of this thread.
But this time it's an animated alembic file so I can't use a blendshape.
So to revive this topic, I assume this is a bug ? Because if you can't even adjust the underlying geometry of a hair groom it would almost completely beat the idea of a procedural groom.
Heck it would be even less flexible then grooming in almost any other 3D app.
Any ideas, besides redoing the groom ?
Thanks
Houdini 19.5.493
I have to adjust the head geometry after I edited a hair groom, but when I replace the head geo the hair groom does not move with the shape of the new geometry. It sticks to the old groom topology, essentially the same problem as what is mentioned at the start of this thread.
But this time it's an animated alembic file so I can't use a blendshape.
So to revive this topic, I assume this is a bug ? Because if you can't even adjust the underlying geometry of a hair groom it would almost completely beat the idea of a procedural groom.
Heck it would be even less flexible then grooming in almost any other 3D app.
Any ideas, besides redoing the groom ?
Thanks
Houdini 19.5.493
Edited by toonafish - Feb. 15, 2023 16:25:18
- toonafish
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Just in case someone else runs into this issue, or I forget.
Looks like Houdini doesn't allow you to simply replace the original Alembic file and reload the scene. That would be too easy, and will screw up your hair groom.
But so far it looks like you can circumvent this bug by keeping the original geometry as the "static" geo for the groom, and then use a shape with the adjusted geometry for the animated skin.
Basically the same as the scene in the example before, but then with an alembic for a blendshape .
But I'll report, maybe it will be fixed some sunny day.
Looks like Houdini doesn't allow you to simply replace the original Alembic file and reload the scene. That would be too easy, and will screw up your hair groom.
But so far it looks like you can circumvent this bug by keeping the original geometry as the "static" geo for the groom, and then use a shape with the adjusted geometry for the animated skin.
Basically the same as the scene in the example before, but then with an alembic for a blendshape .
But I'll report, maybe it will be fixed some sunny day.
- tamte
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if you are talking about Guide Groom, its most likely not a bug
https://www.sidefx.com/forum/topic/88387/ [www.sidefx.com]
if your topo is the same, you can probably use Guide Deform and then new Guide Groom to continue
https://www.sidefx.com/forum/topic/88387/ [www.sidefx.com]
if your topo is the same, you can probably use Guide Deform and then new Guide Groom to continue
Tomas Slancik
FX Supervisor
Method Studios, NY
FX Supervisor
Method Studios, NY
- toonafish
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Hey thanks.
Looks like there the "Guide Deform" used in the default shelf hair groom setup on the obj level. And there's another "Guide Deform" to be connected somehow in the Guide Groom.
I used the default shelf setup, but suspect you're talking about the second flavor guide deform because the obj level guide deform only has a single output.
Does that need a different kind of setup, other then the default shelf one ?
I can't seem to find any info on how to use the Guide Groom inside the groom SOP.
Or am I misunderstanding what you mean ?
Looks like there the "Guide Deform" used in the default shelf hair groom setup on the obj level. And there's another "Guide Deform" to be connected somehow in the Guide Groom.
I used the default shelf setup, but suspect you're talking about the second flavor guide deform because the obj level guide deform only has a single output.
Does that need a different kind of setup, other then the default shelf one ?
I can't seem to find any info on how to use the Guide Groom inside the groom SOP.
Or am I misunderstanding what you mean ?
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