function main() {
  const canvas = document.querySelector('#c');
  const renderer = new THREE.WebGLRenderer({canvas});

  const fov = 45;
  const aspect = 2;  // the canvas default
  const near = 0.1;
  const far = 1000;
  const camera = new THREE.PerspectiveCamera(fov, aspect, near, far);
  camera.position.set(0, 40, 80);

  const controls = new OrbitControls(camera, canvas);
  controls.enableKeys = false;
  controls.target.set(0, 5, 0);
  controls.update();

  const scene = new THREE.Scene();
  scene.back