Sweep Rotation Direction

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Hello,

for a scene with procedural fabric I created animated curves like this:

The animation is controlled by @blend, the moment it reaches 1 (red) the points don't move any more.

Now I have to duplicate these curves using a sweep with surface type "columns". I make the sweep curves twist around the original in the center by a partialtwist. Now unfortunately the reference point with zero twist is at the wrong end of the curve that is moving, so the fixed points are still rotating like crazy.


So I have to revert the sweep direction making it start the twist on the other end. Apparently this can not be controlled by the point order, I have not found any solution with the sort node.
Do you know how to tell the sweep where to start the twist?
Edited by freewind - May 13, 2024 08:32:52
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you can use an attribute (lets say `@twist_mask`) to control the twist, this attribute is a multiplier, so you can manipulate it as much you want such as re-mapping that using curveu attribute and use that mask to drive the twist.

Edited by Mohanpugaz - May 13, 2024 08:55:42

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Screenshot 2024-05-13 182437.png (11.8 KB)

Mohan Pugaz
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Thanks, so I can use an attribute for that. Unfortunately it works cummulative in the sweep node, so I probably have to write a point loop for that. I thaught simply switching directions should be much easier, but if that does not work yet I have to take that effort.

EDIT: I seperated the curves now and used a pointwrangle on them. That seems to work pretty well.

However I faced a new problem now. Before I used "Z Axis (Ignore curve)" for the tangent type. Otherwise the sweep didn't know how to orient the edges. Now with the applied twist that does not work any longer, it stretches the edges depending on their direction. Do you know the right settings for the tangent and up vector to make it either way?
Edited by freewind - May 13, 2024 16:01:43
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