Whenever the automatic mesh generation finds it necessary to locate
a mesh node at a particular position, it will mark this with a fixpoint (red dot). A fixpoint forces
the mesh generation to create mesh lines through this point. However,
there may be other constraints (such as the ratiolimit, for instance)
such that this fixpoint cannot be considered.
If you want to add new fixpoints or change the fixpoint’s usage use
userdefined fixpoints (blue dots).
