Quadrille.cellLength = 50;
let quadrille;

function setup() {
  createCanvas(8 * Quadrille.cellLength, 8 * Quadrille.cellLength);
  quadrille = createQuadrille(8, 8);
}

function draw() {
  background('#6495ED');
  drawQuadrille(quadrille);
  // property read
  text('height: ' + quadrille.height, 20, 20);
}

function mouseMoved() {
  // property write
  quadrille.height = quadrille.mouseRow + 1;
}