* `App.mousemoved(x,y, dx,dy, is_touch)` -- called any time the mouse moves.
  (Based on [LÖVE](https://love2d.org/wiki/love.mousemoved).)

* `App.mousefocus(in_focus)` -- called when the mouse pointer moves on or off
  the app window.
  (Based on [LÖVE](https://love2d.org/wiki/love.mousefocus).)