message: enable path tracer with a default ambient light
diff: @@ -39,6 +39,7 @@ static const std::vector<std::string> g_scenes = {
  "tutorial_scene", "random_spheres", "wavelet", "import"};
  static const std::vector<std::string> g_renderers = {"scivis",
  + "pathtracer",
  "raycast",
  "raycast_vertexColor",
  "primID",
  @@ -483,6 +484,11 @@ void GLFWSgWindow::refreshScene()
  {
  auto world = sg::createNode("world", "world");
  + cpp::Light defaultLight("ambient");
  + defaultLight.commit();
  +
  + world->createChildData("light", defaultLight);
  +
  if (scene == "import") {
  const char *file = tinyfd_openFileDialog(
  "Import a scene from a file", "", 0, nullptr, nullptr, 0);
  