PolyLine Offset generates strange gaps

Hi all,

i'm having a problem that makes me lose my mind...

I have a large amount of curves i need to offset in Z direction. for the most part it works, but for some curves I get gaps, for no apparent reason. The line in the screenshot is a SINGLE open polyline. All vertices are connected.

Still, GAP!

A picture says more than thousand words:

blue: starting line

red: GH generated offset

so far i've tried to

- explode the curve, flip the segments and join them back together before offsetting.

- explode the curve to extract the vertices, draw a new line through those before offsetting.

nothing.

thanks for anyone who can help out.

Cheers,

Chuck

Replies to This Discussion

Permalink Reply by Danny Boyes on February 2, 2011 at 3:08am

Hi Chuck,

Would you post the 3dm files and the ghx so I can have a look, as I don't seem to be able to replicate the problem. Just one of the known 'gappy' curves will do.

Permalink Reply by David Rutten on February 2, 2011 at 3:34am

Hi Chuck,

are you absolutely certain the curve is planar? You cannot offset non-planar curves, it would result in exactly what you're seeing now.

David Rutten

david@mcneel.com

Poprad, Slovakia

Permalink Reply by Chuck on February 2, 2011 at 7:32am

Hi,

I solved the problem. The curve was in fact not planar, since it was generated by projecting to a brep.

I just didn't know what to look for. :) it was 6am and i was still working on it .. thanx

The curves i need to offset are (should be) all parallel when you look at them from the top, so i created a plane, projected them all to that plane and moved the endpoints back to their prototypese, which resulted in perfectly planar offsetable curves.

now i have another problem, it happens while moving the curves...i will post the 3dm and ghx later when i'm at my own computer.

somehow the indexes are scrambled up so the curves get moved to the wrong endpoint...

anyways, thanks for the replies!

Permalink Reply by Chuck on February 2, 2011 at 8:36am

Here we go, the extrusions should be aligned with the lines underneath.

My guess would be that they get scrambled when i input them into the join component, since they're all flattened. right?

Dunno how to fix it though, I appreciate any ideas.

Attachments: