Geodesic pattern on closed surface

Replies to This Discussion

Permalink Reply by David Rutten on July 28, 2013 at 6:53am

Hi Axel,

geodesic operates fundamentally in UV space, measuring pertubations in XYZ space. If you want to simulate a piece of elastic string then it probably makes more sense to work purely in XYZ space.

I attached a very coarse algorithm for doing geodesics in XYZ space. Basically it's smoothing a polyline, then projecting all points back onto the shape. Repeat until the deviation between two states is less than some tolerance value.

It's an approximating algorithm and will never reach the correct value. It'll only ever get closer and closer, but taking longer and longer to do so. Let me know if this sort of solution is more helpful to you.

The inputs are a Brep over which the geodesic should be solved, a curve which is the geodesic starting point and a tolerance value.

--

David Rutten

david@mcneel.com

Tirol, Austria

Attachments:

• XYZGeodesic.gh, 20 KB

Permalink Reply by Axel Körner on July 28, 2013 at 7:18am

Hi David,

thank you very much for your help. But for some reason it doesn't work. The VB component doesn't return a curve.

Permalink Reply by Axel Körner on July 28, 2013 at 7:47am

Hi David,

me again. Now it works, wrong connection. Sorry. But it still returns just the curve in the "short" direction between start and end Point.

Attachments:

• Geodesic.JPG, 18 KB

Permalink Reply by David Rutten on July 28, 2013 at 10:17am

Can you post the geometry so I can try it here?

--

David Rutten

david@mcneel.com

Tirol, Austria

Permalink Reply by Axel Körner on July 28, 2013 at 10:20am

Hi David,

thank you for your help.

At the moment it is just a lofted surface of three closed curves. Nothing specific at the moment.