A Laplacian for Nonmanifold Triangle Meshes
Abstract
We describe a discrete Laplacian suitable for any triangle mesh, including those that are nonmanifold or nonorientable (with or without boundary). Our Laplacian is a robust drop-in replacement for the usual cotan matrix, and is guaranteed to have nonnegative edge weights on both interior and boundary edges, even for extremely poor-quality meshes. The key idea is to build what we call a ''tufted cover'' over the input domain, which has nonmanifold vertices but manifold edges. Since all edges are manifold, we can flip to an intrinsic Delaunay triangulation; our Laplacian is then the cotan Laplacian of this new triangulation. This construction also provides a high-quality point cloud Laplacian, via a nonmanifold triangulation of the point set. We validate our Laplacian on a variety of challenging examples (including all models from Thingi10k), and a variety of standard tasks including geodesic distance computation, surface deformation, parameterization, and computing minimal surfaces.
BibTeX
@article {10.1111:cgf.14069,
journal = {Computer Graphics Forum},
title = {{A Laplacian for Nonmanifold Triangle Meshes}},
author = {Sharp, Nicholas and Crane, Keenan},
year = {2020},
publisher = {The Eurographics Association and John Wiley & Sons Ltd.},
ISSN = {1467-8659},
DOI = {10.1111/cgf.14069}
}
journal = {Computer Graphics Forum},
title = {{A Laplacian for Nonmanifold Triangle Meshes}},
author = {Sharp, Nicholas and Crane, Keenan},
year = {2020},
publisher = {The Eurographics Association and John Wiley & Sons Ltd.},
ISSN = {1467-8659},
DOI = {10.1111/cgf.14069}
}