Surface remeshing - question

[jakisnicknagh]

Hi,
Im working on pygalmesh 7.2 from PIP, but it shouldn't be a problem.

I'm trying to understand, what's happening with my mesh after remeshing.
If we look at lions head mesh is not "watertight", why it's happening and how to avoid it/control it/repair it ?

Im preparing mesh for FEM analysis, so I could make some quick repairs in SpaceClaim and its "ok", but after all I don't get why this problem rises, and how to avoid it ?

Because after all triangles are where they should be, only they are marked as "holes"(red ones).
Are they "flipped" or something ?

I will be grateful for explanation,

Best regards,

[nschloe]

How is the mesh not watertight?