# Circle pattern on free form surface dubbled/normals value problems

Hi, I’m trying to create diagonalized circle pattern on free form surface. but i keep getting the problem with normals and dubble values any suggestion how to fix it ?

circles pattern on surface.gh (13.1 KB)

there are two things going on, the first is that the Diagonalize is producing many many duplicate Vertexes in your Mesh:

the duplicate vertexes -combined with the issue at the second step- is the cause of the presence of these double circles here and there: they are distinct points that happen to be overlapped

the second thing is you are reducing the number of Vertexes by using only the ones inside the curve, but are not simultaneously reducing also the Normals used to create the circles, so they get all accumulated into the last available vertex:

which produces this:

and also makes in such a way at a certain point the the wrong Vertex point is not inheriting its respective normal

I’d use Face Normals instead of Diagonalize, and be sure to sinchro-cull also the Normals:

circles pattern on surface_Re.gh (19.8 KB)

Hi inno, really appreciate the clarification, thank you. one last question do you know why the corner bendings dont have the pattern ? is it related to the cull component?

the non-presence of points/circles on the corner bendings was already like that in your original definition:

and is probably related to the Point in Curve, which works in 2D, so projects points and Surface Edge curve into a plane
it probably happens that the points you are missing appear to be exactly coincident to the outer edge of your surface (Relation type 2), and because you are culling any “non 1” Relation, those are also culled away

to get rid of that issue, you might change the method used to cull points based on proximity to Surface Edges, for instance like this:

circles pattern on surface_Re_Re.gh (21.1 KB)

and to be fair, at this point I don’t know how much useful it is to transform the Surface into a Mesh for this specific task