Grasshopper

algorithmic modeling for Rhino

Another question, create closed polylines (lines), how to?

Hy again,

delaunay mesh was not good solution for this, but i have another question?

How to make closed polylines (regions) from lines that are exploded for example?

Views: 5197

Replies to This Discussion

I tried also just for an example with the weavebird (that creates surface from lines), with the same amount of lines (7000 lines) and it process it in a couple of seconds.

That means it is something with (shortest walk) components (algorithm) that freezes it out.

Hi Andy

I read these long discussions and I think I understood the following:

1) Weaverbird MeshFromLines works for you, but there are two issue:

  - 1.a) The bottom face is sometimes found, and that requires manual work. This is hard to fix automatically, but I think by checking the face normals (up or down) we could get this going.
  - 1.b) There is no strict need to create a mesh if you just require a polyline. This problem is a lateral one, except that meshes in Rhino 5 only handle 3 and 4-sided faces.

2) ShortestWalk works somehow, but finds the same route twice. This is a logical consequence of doing the search with every line with every other line. "A -> B" and "B -> A" will both be found. I think this is also a quite obvious case of quadratic behavior: this means that it will take about 4 times the time, if you feed the algorithm double the amount of geometry. There is no way to optimize this away in the ShortestWalk component, because it is not the source of the issue.

The only simple manner I think available to fix this, would be to write a custom script, maybe with Python, in Rhino WIP. The MeshFromLines functionality is now available to RhinoCommon there. Please let me know when you install Rhino WIP, and I will help starting writing a sample.

Thanks,

Giulio
--
Giulio Piacentino
for Robert McNeel & Associates
giulio@mcneel.com

Ok, i understand it,

What this custom script would look like, i mean does the script will be used in grasshopper or?

Actually what would be the main thing of the script? Creating closed polylines?

Thanks.

> does the script will be used in grasshopper or?

Yes, indeed.

> what would be the main thing of the script? Creating closed polylines?

Calling into RhinoCommon and transforming the result into the polylines that you would need.
Checking the face normals of the mesh is involved.

Giulio
--
Giulio Piacentino
for Robert McNeel & Associates
giulio@mcneel.com

RSS

About

Translate

Search

Photos

  • Add Photos
  • View All

Videos

  • Add Videos
  • View All

© 2024   Created by Scott Davidson.   Powered by

Badges  |  Report an Issue  |  Terms of Service