Retarget muscle from one character to another

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Hello,

Does someone knows if there is a tool for retarget mucles form one character to another? I thik I saw something in the days muscle sytmem was presented but I can not remember now.

Thanks.
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Hi jegupi,

There is no tool for this in Houdini yet, but your best bet is to use an FEM deform node with the muscles as the first input, the target character's skin as the second input, and the source character's skin as the third input. If your two characters do not have matching skin topology, you will need to use a topo transfer node first. Hope this helps
Liesbeth Levick
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Thank you, will try that.
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Sorry, I just tried it out and realised I misremembered it. You do want to use a topotransfer if your skin topology doesn't match, and you do want to use an FEM deform, but not in the way I described before, instead, see the image attached. Basically you tetrahedralize your source skin using a tetconform, and then use a FEM deform to deform the solid source to the target skin. Then you have your muscle and bone surfaces (polygonal NOT tetrahedralized) as the first input of a point deform, the tetrahedralized source skin as the second input, and the FEM deformed target skin as the third input. You will then need to resolidify your muscles as you would for your original setup.

Attachments:
simple_muscle_transfer_setup.png (68.1 KB)

Liesbeth Levick
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Hi Liesbeth, thank you much.
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And one more tip: if the edgeflow on one (or both) of the two characters' skin is a bit too uneven in places, causing weirdness in the deformed muscles, you can try a sculpt node (in H20.5) in relax mode, with symmetry on, to relax the edgeflow on the skin before doing the steps above (but after the topotransfer).
Edited by Liesbeth_Levick - Nov. 12, 2024 13:10:03
Liesbeth Levick
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another usefull trick, thanks so much
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