star clip-path

star.js

var format = x => ((x+.5)*100).toFixed(4)+'%';
var f = ([[a,b],[c,d]]) => format(a)+' '+format(b)+', '+format(c)+' '+format(d);
var r = 1.5 - 0.5*Math.sqrt(5);
var th = Math.PI/2;
var pn = 2*Math.PI/5;

var R = .5;
var result=[0,1,2,3,4].map(k => 
  [[R*Math.cos(th+pn*(k-.5)),R*Math.sin(th+pn*(k-.5))],[r*R*Math.cos(th+pn*(k+0)),r*R*Math.sin(th+pn*(k+0))]]).map(f).join(', ');
console.log(result);