Normal Coordinates as defined by "Discrete Conformal Equivalence of Polyhedral Surfaces" - Gillespi, Springborn, Crane, TOG V40 No4, 2021 This structure assumes that the surface mesh is fixed, and the intrinsic mesh shares the same vertex set as the surface mesh and is initialized with the same connectivity as the surface mesh. Note, it is assumed that the surface mesh has no bow-ties.