Sweep2 Solution found

Grasshopper
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This topic is a lengthy discussion about a problem I encountered with the Sweep2 component in GH Ver. 1.0.004. The strange result I got using the same basic GH code I used in earlier versions was both quite peculiar and confusing. But after fussing with different approaches I finally came up with one that worked:

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The key to success (I think) is creating a sweep arc that spans the widest point between the 2 rail curves, and is also perpendicular to the 2 curves. Doing this is actually easy - just run the 2 curves through the Point on Curve component and vary it’s value so the 2 points end up on the rail curves at their widest point of separation. The attached GH file shows how I did this.

I don’t know how general this solution is, but I have retrofitted it on a couple of older GH files I have and it works OK.

PS: the new version of the Point on Curve component doesn’t seem to be editable except by sliding the thumb. It would be nice if double-clicking it allowed any desired value to be entered.

Sweep2Bug-bb3.gh (22.6 KB)

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PS: the new version of the Point on Curve component doesn’t seem to be editable except by sliding the thumb. It would be nice if double-clicking it allowed any desired value to be entered.

That’s called the “Evaluate Length” component with Normalized set to true (which it is by default)

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Solution? The sweep doesn’t follow the rails in Rhino 5, GH 0.9. New thread?

Sweep2Bug_2018Feb27a
Sweep2Bug_2018Feb27a.png1350×495 69.2 KB

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Seems now the problem is reversed :smiley:

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Hi Joseph - the only thing I can think of is that there is a very mysterious difference between GH 0.9 and GH 1.0 relative to how Sweep2 works. None of this makes any sense to me at all.

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Reversed indeed. Most vexing for sure.