Is it possible for firedrake to compute the global orientation of a surface mesh automatically?

[Alpha-Legion]

I have this question because in theory, the orientability/orientation of a surface is determined by itself.
So it seems unnecessary to initiate the orientation by user. For orientable surfaces, a user only needs to choose one of the two opposite orientations.

[dham]

Happy New Year!

In principle one could do this, as you say up to an arbitrary sign change for the two available orientations. It would involve some work to write the code that propagates the orientation over the surface (one would have to start from the orientation of one cell and spread this over the whole mesh). This would have to happen in parallel so it would take some effort and thought. I would be very happy to consider a PR along those lines, but it's unlikely to be something that the core team finds time to do.