P5js map random example

map-random.js

//instance mode
//map and random functions

var sketch = function(p){
  var bcol = 0;

  //objects
  //in c++ this would be a struct
  var spot = {
    x : 100,
    y : 50
  };

  var col = {
    r : 255,
    g : 0,
    b : 0
  };

  p.setup = function(){
    p.createCanvas(640, 100);
  }

  p.draw = function(){
    p.background(0);
    col.r = p.random(100, 255);
    col.b = p.random(100, 255);
    spot.x = p.random(0, p.width);
    spot.y = p.random(0, p.height);
    p.noStroke();
    p.fill(col.r, col.g, col.b);
    p.ellipse(spot.x, spot.y, 20, 20);
  }
}

var myp5 = new p5(sketch, 'script-map-random');