Add minimum oriented bounding box as direction generator implementation

[DavidSpielman]

Currently, the PrincipalAxisDirectionGenerator uses principal component analysis to determine the direction along the longest principal axis of the input mesh. When the input mesh is roughly a square, the direction chosen is often an axis that goes along the diagonal of the square mesh (which at times is undesirable) instead of along the axis of an oriented bounding box of the mesh (which seems closer to the intent of this direction generator).

Open3D has a method to get the minimum oriented bounding box of a mesh that can handle cases when the input mesh has similar length dimensions. This minimum oriented box defines the principal axes of the mesh sorted from longest to shortest. It should be possible to adapt this implementation to this direction generator.

[DavidMerzJr]

This is an old issue; disagreement about how to handle sometimes wanting object-oriented axes and sometimes wanting globally-orienting axes was one of the major motivations for the no-longer-new design of noether_tpp.

Code that does this with VTK can be found at lines 590-623 of my fork's temeraire branch, here.

The application of that transform happens later, around line 641. Unfortunately, since this is all in VTK, it may not be that useful in the current stripped-down environment.

[marip8]

FWIW, this issue is intended to be a note for us to implement a minimum oriented bounding box as a direction generator at some point in the near future. I just changed the title of this issue to reflect that.

There is not really anything "not robust" about the PCA direction generator. It's just not always what you want. The minimum oriented bounding box would just be another option to choose from for raster direction generation.

Code that does this with VTK can be found at lines 590-623 of my fork's temeraire branch, here.

If I understand correctly, it appears the function you're referencing is a fancy AABB that points the x-axis along the axis of largest extent. I think this would be another nice option as a raster direction generator (alongside PCA and regular AABB), but it's not the same as the minimum oriented bounding box from Open3d that we're talking about implementing