How to get a manifold mesh?

[cshan]

I am using meshoptimizer to do simplification, and then use pmp library to fix holes, but pmp need a manifold mesh, I always got a Complex vertex/Complex edge TopologyException. does meshoptimizer have anyway to generate a manifold mesh?

[zeux]

There are no algorithms in meshoptimizer to produce a manifold mesh from a non-manifold mesh.