Toroid p5js experiment #2

Toroid-02.js

function setup() {
  createCanvas(800, 800, WEBGL);
}

function draw() {

  background("#111515");

  let scaleFactor = 1;

  let R = 200;
  let r = 60;

  let n1 = 17;
  let n2 = 57;

  let c6 = ["ff595e","ffca3a","8ac926","1982c4","6a4c93"];
  let colors = c6.map(function(i) { return '#' + i; });

  strokeWeight(3);
  noFill();
  scale(scaleFactor);
  i = 0;
  for(t = 0; t < 1031; t++) {

    if (t%30 == 0) {
      beginShape();
    }
    let th  = (t % n1) * 2 * PI / n1;
    let phi = (t % n2) * 2 * PI / n2;

    let x = R*cos(phi) + r*cos(phi)*cos(th);
    let y = R*sin(phi) + r*sin(phi)*cos(th);
    let z = r*sin(th);

    curveVertex(x,y,z);

    if (t%30 == 29) {
      endShape();
      stroke(colors[i % colors.length]);
      i++;
    }
  }

  // draw palette
  for(j = 0; j < colors.length; j++) {
    fill(colors[j]);
    stroke(colors[j]);
    square((j+1)*30, 300, 20);
  }
}