message: WebGL: tweak helmet demo for shadows.
diff: @@ -10,7 +10,7 @@ html, body { height: 100%; }
  body { margin: 0; overflow: hidden; }
  #container { position: relative; height: 100%; }
  canvas { position: absolute; width: 100%; height: 100%; }
  -#messages { position: absolute; width: 100%; height: 100%; padding-left: 10px; }
  +#messages { position: absolute; width: 100%; height: 100%; padding-left: 10px; color:white; }
  </style>
  </head>
  <body>
  @@ -48,7 +48,7 @@ class App {
  const iblDirection = indirectLight.getDirectionEstimate();
  const iblColor = indirectLight.getColorEstimate(iblDirection);
  - indirectLight.setIntensity(30000);
  + indirectLight.setIntensity(50000);
  const skybox = engine.createSkyFromKtx(sky_url);
  this.scene.setSkybox(skybox);
  @@ -56,7 +56,7 @@ class App {
  const sunlight = Filament.EntityManager.get().create();
  Filament.LightManager.Builder(LightType.SUN)
  .color(iblColor.slice(0, 3))
  - .intensity(iblColor[3])
  + .intensity(150000)
  .direction(iblDirection)
  .sunAngularRadius(1.9)
  .castShadows(true)
  @@ -103,6 +103,7 @@ class App {
  this.swapChain = engine.createSwapChain();
  this.renderer = engine.createRenderer();
  this.camera = engine.createCamera();
  + this.camera.setExposure(32, 1/125.0, 100);
  this.view = engine.createView();
  this.view.setCamera(this.camera);
  this.view.setScene(this.scene);
  