This is a partial port of Darren Engwirda's MATLAB Mesh2D package (2017). Python refactorization by J. Dorsett (2024).

Darren Engwirda describes the functionality in his Smooth2.m:

"This routine is loosely based on the DISTMESH algorithm, employing a "spring-based" analogy to redistribute mesh vertices. Such an approach is described in: P.O. Persson and Gilbert Strang. "A simple mesh generator in MATLAB." SIAM review 46(2) 2004, pp: 329--345. Details of the algorithm used here are somewhat different, with an alterative spring-based update employed, in addition to hill-climbing element quality guarantees, and vertex density controls."

Smooth2D is a powerful 2D mesh smoothing algorithm that we use to generate meshes from a user-generated set of nodes and vertices created using Delaunay triangulation. Smooth2D accepts a nodeset (vert), triangulation set (tria), and a connectivity set (conn), which references edges that are to remain fixed.