Work out angles and distances between objects that have x and y properties.

angleTools.js

// es6
const at = {
	angle: (a,b)=>Math.atan2(b.y-a.y,b.x-a.x)/Math.PI*180,
	dist:  (a,b)=>Math.sqrt((a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y)),
	step:  (a,s)=>({x:s*Math.cos(a*Math.PI/180),y:s*Math.sin(a*Math.PI/180)})
}

// es5
var at = {
	angle: function(a,b){return Math.atan2(b.y-a.y,b.x-a.x)/Math.PI*180},
	dist:  function(a,b){return Math.sqrt((a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y))},
	step:  function(a,s){return {x:s*Math.cos(a*Math.PI/180),y:s*Math.sin(a*Math.PI/180)}}
}