 webglfundamentals: url */

  function degToRad(d) {
    return d * Math.PI / 180;
  }

  const settings = {
    cameraX: 2.75,
    cameraY: 5,
    posX: 2.5,
    posY: 4.8,
    posZ: 4.3,
    targetX: 2.5,
    targetY: 0,
    targetZ: 3.5,
    projWidth: 1,
    projHeight: 1,
    perspective: true,
    fieldOfView: 45,
  };
  webglLessonsUI.setupUI(document.querySelector('#ui'), settings, [
    { type: 'slider',   key: 'cameraX',    min: -10, max: 10, change: render, precision: 2, step: 0.001, },
    { typ