Connectivity

The connectivity of a set of surface patches can be identified following the patch conventions and the Bezier mesh conventions.

Patch Interfaces

To identify common edges and common corner points beween patches of a surface, the identifyInterfaces function is provided

using NURBS
Patches = readMultipatch("assets/sphere.dat")

interfaces, commonVtxs = identifyInterfaces(Patches, tol=1e-3)

Note

To determine whether two patches share a common edge, in the current implementation only the corner points are compared. The maximim allowed distance between two points to be identified as one can be specified by tol.

The returns are vectors of Interface structures, which are a winged edge like structure:

struct PatchInterface{I}
    patchID::I
    localEdge::I
end

struct Interface{I}
    patch1::PatchInterface{I}
    patch2::PatchInterface{I}
    orientation::I              # edges normal to interface have same orientation
    reverse::Bool               # adjacent edges have same orientation
end

To get patch-wise information the getPatchInterfaces function is provided

ifPatchwise = NURBS.getPatchInterfaces(Patches, interfaces, commonVtxs)

Bezier Mesh

To extract information about the adjacency of a virtual Bezier mesh, the

bezierAdj = NURBS.bezierAdjacency(interfaces, commonVtxs, 3, 3, length(Patches))

Tip

To determine all connectivity information, the Connectivity function can be used, which returns a struct containing the interface vector, the patchwise vectors and the Bezier adjacency:

using NURBS

Patches = readMultipatch("assets/sphere.dat")

cty = Connectivity(Patches, 3, 3, tol=1e-3)

cty.interfaces
cty.patchInterfaces
cty.bezierAdjacency