Beispiel aus dem Kapitel Processing in JavaScript.
var anzahl = 10;
var xpos = [];
var ypos = [];
var xspeed = [];
var yspeed = [];
function setup() {
let canvas = createCanvas(200, 200);
canvas.parent('sketch');
for (let i = 0; i < anzahl; i++) {
xpos.push(random(10, width-10));
ypos.push(random(10, height-10));
xspeed.push(random(-4, 4));
yspeed.push(random(-4, 4));
}
}
function draw() {
background(0);
for (let i = 0; i < anzahl; i++) {
ellipse(xpos[i], ypos[i], 20, 20);
xpos[i] = xpos[i] + xspeed[i];
ypos[i] = ypos[i] + yspeed[i];
if (xpos[i] > width-10 || xpos[i] < 10) {
xspeed[i] = -xspeed[i];
}
if (ypos[i] > height-10 || ypos[i] < 10) {
yspeed[i] = -yspeed[i];
}
}
}