As the world of 2D graphics and slint often has minus values for x, y positions you have to be a bit more knowledge to deal with the output from Math.atan. Having atan2 where you can just put in both the x and y values to get an answer would be great.
Marked as a good first issue, because one can basically grep add a BuiltinFunction::ATan2. One can grep for BuiltinFunction::ATan to see all the place that needs changing.
As the world of 2D graphics and slint often has minus values for x, y positions you have to be a bit more knowledge to deal with the output from Math.atan. Having atan2 where you can just put in both the x and y values to get an answer would be great.