Hi everyone,
I’ve got a problem getting consistent behavior with Twisted Tube parameters. It seems that the Twisted Box Tube (Variable) behaves as if it’s Weighted flag is always on.
I have a line with parameters generated by the z locations of points. The screenshot shows both the twisted box tube variable component and a twisted box curve variable for reference, using the same input parameters, notice the difference.
The next screenshot shows that toggling the weighted flag on the curve component makes it display the same behavior. Toggling weighted on the Tube components makes the effect more pronounced, as if applied double.
Attached you can find the grasshopper code as well.
Am I missing something here or is there something going wrong in the components? Any help or feedback would be much apprectiated!
PFTBTV-param.gh (13.9 KB)
I don’t like bumping posts, however I will do it once here. I would like to know if anybody else either:
1: Encountered this issue as well
2: Solved it
3: Found a workaround
Since I don’t like wasting anybody’s time this will be my last post in this thread if no replies follow.
Thanks for any feedback anyway. 
I’ve got a problem getting consistent behavior with Twisted Tube parameters. It seems that the Twisted Box Tube (Variable) behaves as if it’s Weighted flag is always on.
It is not, weighted means it is taking into account the control points and potential curvature and weighting closer control points or tighter curvature stronger, That is why it sucks inward when you toggle it on in your case cuz your polyline is more dense in its center.
REMEBER, parameters are not distances, they are related to the parametrization of the rail curve. The same way Gh / Rhino uses evaluate length (not weighted) or evaluate curve (weighted).
I have a line with parameters generated by the z locations of points. The screenshot shows both the twisted box tube variable component and a twisted box curve variable for reference, using the same input parameters, notice the difference.
You don’t have a line, you have a polyline with unevenly spaced control points (unevenly spaced parameters). Your parameters are also unevenly spaced and are reflecting these control point locations since you used them to make the control points. So for instance if you wanted equal spaced boxes, use equal spaced parameters.
Now if you turn weighted on they will still suck inwards because of your polylines control point density in the middle.
But if you really did use a line then weighted option would actually do nothing because there are no control points (or curvature) to weight the spacing.
I’ve got a problem getting consistent behavior with Twisted Tube parameters
This is how curve parameters work. Hope it helps.
As for why they are different from twisted box curve to twisted box tube it is weird yes. Seems something changed in newer Rhino with frames that I will look into.
Hey Michael,
Thank you very much for your thorough explanation and pointing my errors, much obliged! Hope this could as well point to the different behaviors between twisted box tubed and curves.
Sincerely,
Justus
Just reuploaded V3.0 with those components working correctly now. Go redownload and install it.
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