On only one axis (the x axis in this example), I'd like to orient instances so that they are all rotated uniformly around right angles, like this:
I think this is theoretically possible if the axis of the edge could be used to rotate the instance appropriately:
and the two neigboring faces' normals could be used to provide the other two axis (in this example just the top face was needed to complete the rotation):
I've referenced these three questions in particular for a solution:
How to properly orient instances along corner edges
Instance alignment on corners while maintaining right angles
geometry nodes - Get Faces of Edge
Of course the first of these questions is almost the same problem I'm asking about, however because I'm looking to calculate one axis at a time with only right angles, and because the prior solution to this similar problem wasn't consistently outputing correct rotations for me, I hope this is worth looking at for its albeit nuanced difference.
My process so far has been to capture the edge vector and sample the neighoring faces' normals using Robin Betts' setup from the third question above, then try lots of artist-attempted-math of which none has been successful:
If anyone has any ideas on how to specify which of the neighboring faces are used for which axis, along with any other mistakes in my attempt I'd appreciate very much hearing them.