KineFX Curve solve - undesirable mesh deformation

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Hi,

I was trying to make a spine rig using a curve solve VOP.
I tried to follow the Houdini 18.5 KineFX presentation, but I got to the problem.
When I look at the skeleton, it seems to follow the fitted curve very well.
When I use a bone deform node the mesh gets distorted in a weird way.
Here are the screenshot and source file:
Edited by wolskikrzys - Nov. 17, 2020 13:55:12

Attachments:
CurveSolveIssue.PNG (321.5 KB)
CurveForSpineTest.hiplc (386.7 KB)

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Hi,
The UP axis and LOOK AT axis should be different, for transformations to be correctly calculated.
So, try to orient your joints along the Z-axis for ex
hip attached

Attachments:
CurveForSpineTest_v01.hiplc (392.8 KB)

https://linktr.ee/Deviner_vfx [linktr.ee]
Linux Arch | RTX 3090 | Ryzen 9 5950X | X570-PRO
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deviner
Hi,
The UP axis and LOOK AT axis should be different, for transformations to be correctly calculated.
So, try to orient your joints along the Z-axis for ex
hip attached

Oh, it worked very well for you. I still wonder how you make reorient joints node to orient them that nicely.
I was trying to reorient them before, but I always get very messy orientations.
Even with reorient joints I cannot reproduce your results. What do I do wrong?
Here are the joint after reorient operation… I also attach hip file.
Edited by wolskikrzys - Nov. 17, 2020 17:50:28

Attachments:
ReorientJoints.PNG (98.2 KB)
CurveSolveIssue.PNG (195.6 KB)
JointReorient.hiplc (363.8 KB)

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Your first version of the skeleton was correct, you need to use a “skeleton mirror” too. Pay attention to the joints orientation.
Skeleton allows you to adjust the orientation
check this out
https://www.sidefx.com/docs/houdini/character/kinefx/skeletons.html [www.sidefx.com]
especially the “Orienting joints” part

Attachments:
CurveForSpineTest_v02.hiplc (371.8 KB)

https://linktr.ee/Deviner_vfx [linktr.ee]
Linux Arch | RTX 3090 | Ryzen 9 5950X | X570-PRO
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53 posts
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deviner
Your first version of the skeleton was correct, you need to use a “skeleton mirror” too. Pay attention to the joints orientation.
Skeleton allows you to adjust the orientation
check this out
https://www.sidefx.com/docs/houdini/character/kinefx/skeletons.html [www.sidefx.com]
especially the “Orienting joints” part

Thanks for fixing the mesh and for the link to docs.
I've been searching for such information, but it seems this webpage is still too fresh for google.
It was a great lecture.
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