Comment 9 for bug 170498

In MyPaint can do this. You have two menu entry to rotate the view 25 degrees, one clockwise, other the reverse, and you can map them to any key you choose, so you can rotate to an (almost) arbitrary angle by repeatedly pushing the key. I find this extremely fast and useful, since a lot of us work with one hand at the pencil, and the other at the keyboard. Using the strip would be better, but not all tablets have that option, and some people doesn't have a tablet ;)

For me, rotate 90, 180, 270 doesn't make the cut at all; and selecting a menu entry, introducing a number, press OK is painfully slow and totally breaks my workflow. I don't think anybody needs such precission to rotate the view; I think the MyPaint system is much better, and maybe could be better optimized in code.

An improvement would be make the steps configurable, so instead of have a fixed rotation of 25 you can configure it to be 12, 45, 90 or whatever you want.