I'm porting over an old flash app that used to rely on this third-party contribution:
http://proj.lamb-mei.com/handlesheet/ (you need to enable flash)
Source code is at https://github.com/lamb-mei/HandleSheet
It's basically just a button that you touch and move around, and it causes the target to rotate, scale, and move with it.
Looks like this:
Now I want to implement it from scratch in PIXI. I know I need to somehow get the rotation based on trigonometry calculations of the initial points and updated points of the button and target DisplayObject... and I'll experiment around with that, but thought someone here might know offhand 