createCanvas(400, 400, WEBGL);

}

​

function draw() {

  background(220);

  strokeWeight(3);

  beginShape();

  //red (also works with fill)

  stroke(255, 0, 0);

  vertex(0, -100);

  //green (also works with fill)

  stroke(0, 255, 0);

  vertex(-100, 100);

  //blue (also works with fill)

  stroke(0, 0, 255);

  vertex(100, 100);

  endShape(CLOSE);

}