Using ArcBlend to close a curve can result in non-closed curves in a small percentage of arc blend attempts. Info Rhino version: 7.30.23163.13001, 2023-06-12 This occurs with the following ArcBlend Options: Trim=Yes Join=Yes Trim=Yes Join=No Examples ArcBlendTrimmingBugs.3dm (63.5 KB) The oper…

I suspect that arcblend uses a point-curve intersection solver that is nondeterministic and rarely freaks out and gives us wrong answers. I also suppose that it might be difficult to solve the instability in the intersection solver. However, the solver works most of the time, and the wrong solutions…

Hi @max.suica I could not repeat it here with these examples. Both gave me a closed curve after trimming and joining (both in command as well as afterward) Do you have other examples that you could share?

Hi @Gijs , thank you for your attention to this problem. Here are two simpler examples, using a 3 segment polyline. They are both of the overtrim variety, where the operation cuts too much from one of the input curves. In the first configuration I move one endpoint to a random point [ArcBlendErrorG…

@max.suica I got it now, thanks RH-75955 arcblend doesn’t trim correctly [image]

Awesome! The work ticket now captures the most common kind of error: Gaps. The result is open with a visible gap. There are two other kinds of open curve errors that affect my work: No Trim. The result is open where Arcblend didn’t trim one end of the curve. Degenerate Ends. The result is ope…

thanks @max.suica for your detailed tests, I’ve added those to the yt

Bug report: ArcBlend may fail to close curves

Rhino

brian (Brian Gillespie) August 8, 2023, 10:35pm 8

RH-75955 is fixed in the latest WIP

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Bug report: ArcBlend may fail to close curves

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