Rotation causing strange behaviour

I have two circles in grasshopper. The inner circle is left alone and the outer circle is rotated. Then they are both divided into equal length segments. The division points are then rearranged with flip matrix.

This way I was hoping to connect the two top points with each other. I would expect that I could connect those two points (highlighted in green) no matter how much or little I rotate the outer circle. But that's not what happens...

Any ideas or insights? I really don't understand what's going on.

Attachments:

rotation.gh, 6 KB

Replies to This Discussion

Permalink Reply by Arie-Willem de Jongh on March 15, 2012 at 10:42am

This def connects the two top points. Let me know if this is what you wanted?

Cheers!

Attachments:

rotationv1.gh, 7 KB

Permalink Reply by Lars Renklint on March 16, 2012 at 2:03am

Thank you Arie-Willem!

That works fine with two circles. Not sure about how it would work with many circles. The idea is to create maybe 20 circles with say 20 division points and connect those points. Here's 4 circles with one division point.

Permalink Reply by Danny Boyes on March 15, 2012 at 10:44am

As to why it is happening I cannot say (as I'm 0 for 1 today in pointing the finger at bug I'm going to refrain from any possible false accusations)

But a work around would be to rotate your inner circle by a tiny amount to take it out of plane.

Obviously a horrendous solution but needs must

Permalink Reply by Lars Renklint on March 16, 2012 at 2:13am

Thanks Danny!

My first thought when things get weired is always that it's a bug, though I usually wait a bit before I say so in this forum...

Anyway, your suggestion does make it a bit better. Here I've added a couple of circles and with a small rotation I get what I was expecting.

But with a bit more rotation the problem is back.

Permalink Reply by Lars Renklint on March 16, 2012 at 2:31am

It's like in this particular case, with this amount of rotation that Grasshopper connects the three inner circles correctly, but then chooses the wrong side of the outermost circle.

Permalink Reply by Lars Renklint on March 16, 2012 at 3:16am

Ok, now I do think I have to ask, is this a bug?

The circle to the left uses the Vector rotation component, and the one to the right is rotated with the Rotate axis component.

What I was expecting is that they both would behave like the circle to the right when rotated.

Attachments: