(reply didn't go to list as I expected, grr..)
Naw, it should still work normally. I've done aligned & rotated text under windows before with DrawTextW, you still pass the rect like you would if it wasn't rotated and set the alignment flags. The world transform should take care of getting it all rotated to where it is supposed to be with the alignments in the right place.
Maybe, but builtin gdiplus has its own world transform and doesn't use the gdi32 one. That's what transform_and_round_points is for.
Ok question then, how do I separate this into two patches? Never done anything with patches like this before so this is a first for me.
Just make two commits in Git, and format-patch will create two patch files.