It's a generalization of B-splines, called U-splines (splines over Unstructured meshes). If anyone is interested in the math behind it on the level of a journal

It's a generalization of B-splines, called U-splines (splines over Unstructured meshes). If anyone is interested in the math behind it on the level of a journal article, the last two links here go into the technology in detail: https://docs.coreform.com/latest/html/coreform-public/index.html https://docs.coreform.com/latest/html/coreform-public/index.... (Disclaimer: I work for Coreform, developing U-splines)