// frameRate(12);

  createCanvas(400,400)

  background(220, 255, 220);

  noStroke();

  fill(255,100,255);

  polygon(X,Y,R,N, t);

}

​

var X = 200;

var Y = 200;

var R = 100;

var N = 6;

var t = 0;

​

function draw() {

  background(220,255,220);

  fill(255,100,255);

  polygon(X,Y,R,N, t);

  fill(0);

  text("theta = " + nf(-t * 180 / PI,0,2), 200, 200);

}

​

function keyPressed() {

  if (keyCode == UP_ARROW) {

    t = t - PI/90;

  }

}

​

​

function polygon(x, y, radius, npoints, theta) {

​

  //degrees = radians × 180° / π

  //radians = degrees × π /180°

  var angle = TWO_PI / npoints;     // TWO_PI is the equivalent of 360 degrees

  console.log("radians: " + angle);

  console.log("degrees: " + (angle *180/PI));

​

  beginShape();

    for (var a = theta; a <= TWO_PI; a = a + angle) {

      var sx = x + cos(a) * radius;

      var sy = y + sin(a) * radius;

      vertex(sx, sy);

      console.log("sx, sy: " + sx + ", " + sy);

    }

  endShape();

​

}

​