Generate geometry input files for the GMSH mesh generator (http://geuz.org/gmsh) and convert the GMSH mesh file to shapefiles that can be imported into QGIS.

Copy the gmsh sub-directory in your QGIS "/python/plugin/" directory (e.g. ~/AppData/Roaming/QGIS/QGIS3/profiles/default/python/plugins under Windows 10). Then enable it through the "Plugins>Manage and Install Plugins..." menu.

The different actions are accessible through the "Plugins >Gmsh" menu. See the tutorial on the wiki page.

• QGIS Geographic Information System. Open Source Geospatial Foundation Project. http://qgis.osgeo.org
• Gmsh: a three-dimensional finite element mesh generator with built-in pre- and post-processing facilities. C. Geuzaine and J.-F. Remacle. International Journal for Numerical Methods in Engineering 79, 1309-1331, 2009. http://geuz.org/gmsh
• Multiscale mesh generation on the sphere. J. Lambrechts, R. Comblen, V. Legat, C. Geuzaine and J.-F. Remacle. Ocean Dynamics 58, 461-473, 2008.