to be used in https://brunovcosta.github.io/explainer/

sphere.coffee

g9 {
  r: 200
  t: 10,
  p: 10,
},(d,c)->
  points = 20

  sphere = (x,y)->
    [d.r*Math.cos(d.p+x*2*Math.PI/points)*Math.sin(y*Math.PI/points),
     d.r*Math.sin(d.p+x*2*Math.PI/points)*Math.sin(y*Math.PI/points),
     d.r*Math.cos(y*Math.PI/points)]
  for x in [0..points]
    for y in [0..points]
      c.point sphere(x,y)[0],sphere(x,y)[2],{'r': (1-0.5*sphere(x,y)[1]/d.r)*5, fill: "hsl("+(50*(1+0.5*sphere(x,y)[1]/d.r))+", 100%, "+(50*(1+0.5*sphere(x,y)[1]/d.r))+"%)"}
      c.line sphere(x,y)[0],sphere(x,y)[2],sphere(x+1,y)[0],sphere(x+1,y)[2], 'stroke-width': 0.1
      c.line sphere(x,y)[0],sphere(x,y)[2],sphere(x,y+1)[0],sphere(x,y+1)[2], 'stroke-width': 0.1