var items = [];

COLS = 6;

MARG = 45;

​

function setup() {

  rectMode(CENTER)

  textAlign(CENTER);

  createCanvas(400, 400);

  for (var y = MARG; y < height-MARG ; y += MARG ) {

    for (var x = MARG ; x < width-MARG ; x += (width/COLS))

    items.push(new Item(x,y ))

  }

}

​

class Item {

  static uid = 0;

  constructor(x,y) {

    this.pos = createVector(x,y)

    this.id = ++Item.uid;

  }

  show() {

    rect (this.pos.x ,this.pos.y, MARG-3)

    text(this.id, this.pos.x-5,this.pos.y+5)

  }

}

​

​

function draw() {

  background(220);

  for (const i of items){

    i.show();

  }

  noLoop();

}