Delaunay mesh mis-interpreting certain points for inner points, should be naked edges

Grasshopper
1

Hi all,

After spending a while on grasshopper I have still trouble with this area of meshes. It doesn’t seem to compute with me.

Here is an image of the issue:

ViewOfDelaunayMesh
ViewOfDelaunayMesh1224×816 400 KB

Points 3, 5, 7, 9, 11 and 13 are counted as interior edges and not Naked edges as I would like them to. The mesh should follow those points back to point 1, not connecting 15 to 1. Hope that makes sense.

How would I go about changing this behaviour? I’ve been numbering the points and trying to reorganise them, without much luck.

Thanks,
Thom

GrasshopperHelp.zip (162.9 KB)

2

Hi Thom,
I believe your problem is caused by the Delaunay mesh being a convex diagram, which means it is not able to produce shapes like “C”, which would be filled into “O” shape.

https://www.mathsisfun.com/definitions/convex.html

You could create a closed polyline instead and then use it to produce a Boundary surface.

Cheers
Jonas

1 Like
3

Thanks Jonish, that was really useful to know. I’ve used the mesh as it was and “delete faces” that I didn’t need so now I have the surface I wanted. Now the problem is that I am struggling to create a smoothed alternative mesh that takes the original mesh as support but show an alternative a bit more flowy, if that makes sense, and less jaggered that the one I have at the moment.

The closed polyline was a good idea but I wasn’t getting anything back that was conclusive with the boundary surface.