If I understand the problem correctly, there are two closely spaced fronts between which triangles must be formed.
Possibly limited by a vertical cut?
It may also be possible to adapt E. Hartmann’s triangulation method here.
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I have already adapted it specifically to a few scenarios.
I don’t usually start with a hexagon, but rather with a simple triangle.
In this example, you can clearly see the progress of the formation of triangles.
Triangulation sphere with holes see the example TriangulationSphereWithHoles
I would first determine the smallest distance between two adjacent vertices in both fronts. Possibly also the minimum distance between the two fronts. This measurement is then taken as the approximate triangle length of the triangulation.
You need at least an approximate normal for the current point. With a sphere, this is trivial, of course, but it was also possible with SDFs.
Generation of SDFGeometry online and locally