A Solve Curve rig:
When stretch=0, it doesn't hold the position of the tip bone:
When stretch=1, it doesn't hold the length of bones:
I'd like it to have both. Just like a two-bone IK. Is it possible?
KineFX: Is it possible to solve IK with more than 2 bones?
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- raincole
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Is it possible to have an IK chain with more than 2 bones? I tried Solve Curve VOP, however it can't keep the positions of start/end, and the length of bones at the same time.
A Solve Curve rig:
When stretch=0, it doesn't hold the position of the tip bone:
When stretch=1, it doesn't hold the length of bones:
I'd like it to have both. Just like a two-bone IK. Is it possible?
A Solve Curve rig:
When stretch=0, it doesn't hold the position of the tip bone:
When stretch=1, it doesn't hold the length of bones:
I'd like it to have both. Just like a two-bone IK. Is it possible?
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- raincole
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I tried to "binary search" the position of control points to find a best-fitting curve. It actually kinda works. But it's rather wasteful (it needs to run 70+ times Measure SOP to get a smooth result). It runs well for a single spine, but I thought it might be problematic when the rig gets more complicated.
I still wonder whether there is a more proper way to do this.
I still wonder whether there is a more proper way to do this.
Edited by raincole - 2022年3月30日 04:13:26
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- element33
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You may have to use an IK Solver VOP in a Rig Attribue Vop. The IK Solver VOP doesn't limit the number of bones to 2. In theory, the simplest setup is an IK Solver and SetTransforms, but you may need to fiddle with control points to get it right.
This YT video shows this, though the narration is rather confusing.
KineFX | IK Solver VOP [www.youtube.com]
This YT video shows this, though the narration is rather confusing.
KineFX | IK Solver VOP [www.youtube.com]
Edited by element33 - 2022年3月30日 14:38:39
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- raincole
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element33
IK Solver VOP
I don't think it works for my case tho. As my images show, I need an S-Shape curve, just like a typical bezier curve. IK Solver VOP's input are Root/Goal/Twist (3 points). I don't think it's mathematically possible to describe an S-Shape curve (order of 4) with 3 points (order of 3).
Edited by raincole - 2022年3月30日 22:06:53
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- mestela
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- raincole
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