Extract edge curve

Hi all,

I'm trying to extract the edge curve of a surface that consists of joined surfaces.

To do this I thought I could use 'join Brep', followed by 'Brep components', but it just returns me the edge curves of the unjoined situation.

Any ideas?

Thanks

Bert

Replies to This Discussion

Permalink Reply by Benjamin Golder on June 3, 2010 at 1:14am

This might work sometimes:
Get the edge curves of the unjoined surfaces. Join them together to form closed curves, project them to a plane, use a region union with that plane to combine them into one curve, then project them back on to the brep with a vector perpendicular to the plane.

Attachments:

ScreenHunter_03 Jun. 03 00.12.jpg, 79 KB
ScreenHunter_02 Jun. 03 00.12.jpg, 33 KB

Permalink Reply by Bert Belmans on June 3, 2010 at 1:52am

Hi Benjamin.

Thanks for your reply. I've tried what you proposed, but without succes.
I've attached my grashopper script. It's rather unstructured, but I've marked the surfaces that I need to join to define their edge curve.

Before you can do anything, you'll have to define a curve in the front view in rhino.

I hope someone can help me with this

Greetings

Bert

Attachments:

parmametric5.ghx, 835 KB

Permalink Reply by Benjamin Golder on June 3, 2010 at 4:45am

Hi Bert,

I'm not sure if you are trying to get what I've taken a picture of here, or if you are trying to avoid holes. For the pictures attached, I just scaled your circles from centers by a tiny bit, so that they overlap just slightly. If you don't do this, then they only intersect at a point. If you need just the exterior curves, you can add a big closed rectangle to the union with the circles, and that should leave you with a curve that simply creates a boundary around the grid of circles.

Attachments: