1 Math.euclideanDistance = function(a, b) {
 2     let xd = (a.x - b.x), yd = (a.y - b.y);
 3     return Math.sqrt(xd * xd + yd * yd);
 4 };
 5 
 6 Math.angleRadians = function(a, b) {
 7     return Math.atan2(b.y - a.y, b.x - a.x);
 8 };
 9 
10 Math.angleDegrees = function(a, b) {
11     return Math.angleRadians(a, b) * 180 / Math.PI;
12 };
13 
14 Math.midpoint = function(a, b) {
15     return {
16         x: (a.x + b.x) / 2,
17         y: (a.y + b.y) / 2,
18     };
19 };
20 Math.circupoint = function(origin, radius, radians) {
21     return {
22         x: origin.x + radius * Math.cos(radians),
23         y: origin.y + radius * Math.sin(radians),
24     };
25 };