How can I make this?

Hello, I am a novice in Grasshopper and would like to understand how to make this graphic:

I want use this technique to visualize populations in various cities. Can anyone give me advice on how to go about this?

Thanks!

Tom

(image credit: http://www.eric-hull.com/)

Replies to This Discussion

Permalink Reply by peter fotiadis on July 18, 2015 at 1:00am

Rather easy that one ... but ... by no means a task for a novice.

Anyway ... just for the record:

You can do it either modifying control points of a flat nurbs or vertices of a flat mesh. Using either components or code. I'll describe the code option.

case nurbs:

1. Create a flat 4 pts nurbs that engulf the US shape. Trim the nurbs against the shape.

2. Get the nurbs control points (NCP). For instance this function does that:

3. Find the NCP that is closest to a given "city point". Delete the old NCP and replace with a point derived from the "city point" (add some Z value from some List). Repeat until all desired "city points" are consumed.

4. Create a new nurbs using this method (Udegree, Vdegree = 1):

NurbsSurface.CreateThroughPoints(surfCntrPts, UCount, VCount, Udegree, Vdegree, closeInU, closeInV);

case mesh:

1. Sample the US curve into a boundary surface and convert it into a mesh. That's tricky (Note: use Daniel's Meshmachine to control the mesh).

2. Get the mesh vertices List (and a vertex to vertex and vertex to faces connectivity tree).

3. Find the vertex that is closest to a given "city point". Delete the vertex AND the adjacent faces and replace with a vertex derived from the "city point" (add some Z value from some List) AND new faces from that point to all neighbor vertices. Repeat until all desired "city points" are consumed. Well... it's a "bit" more complicated than that but ... as I said ... not a task for a novice by any means.

Permalink Reply by David Rutten on July 18, 2015 at 2:00am

WHY would you resort to C# for this? It's totally not needed and overly complicated for a beginner.

Permalink Reply by David Rutten on July 18, 2015 at 2:10am

Here's one way to do it in Grasshopper.

Attachments:

humps.gh, 14 KB

Permalink Reply by Nik Willmore on July 18, 2015 at 3:23am

The molecules of geometry aspect of this is delightful to be initially confused by. So by using grafting to create a repeated subroutine, each influence point independently perturbs it's surroundings, unaware of the other points, but these local single point fields then add up to a smooth result.

RSS