gui = {
const gui = new datGUI.GUI();
gui.add(controls, "rotationSpeed", 0, 0.5);
gui.add(controls, "addCube");
gui.add(controls, "removeCube");
gui.add(controls, "outputObjects");
gui.add(controls, "numberOfObjects").listen();
document.getElementById("datGUI").appendChild(gui.domElement);
return gui;
}