How do I import my geometry into Gerris?
It depends how the geometry is defined. If it has an analytical representation, the easiest is to use implicit surfaces. Have a look at the GfsSolid and GfsSurface documentations. If the geometry was created using a CAD package, you need to convert it into a set of triangulated surfaces and be able to export it in the GTS format (very simple, described here) or alternatively in the STL format (which can be converted to GTS using the stl2gts program). The tricky bit is that the surfaces you export must represent proper solid objects i.e. they must be orientable, closed, manifold and non self-intersecting surfaces. Note that this is an issue only for explicit surfaces.
