ENH: add directionalMeshWave functionality

Summary

For a given point within a given mesh, the existing meshWave method gives the orthogonal distance to a patch. In meshes with very steep terrain (e.g. a hill of 90 [deg]), this might be problematic for the fields that require the distance to the patch associated with the terrain surface.

directionalMeshWave is a variant of meshWave distance-to-patch method, which ignores the component in the specified direction. Can be used e.g. to calculate the distance in the z-direction only.

Requirement by CENER Implementation by Mattijs Janssens

Resolved bugs (If applicable)

None

Details of new models (If applicable)

meshWave

directionalMeshWave

Risks

None