message: lightbulb: clear background
  Fixes
diff: #include <filament/Material.h>
  #include <filament/Scene.h>
  #include <filament/LightManager.h>
  +#include <filament/Renderer.h>
  #include <filament/RenderableManager.h>
  #include <filament/TransformManager.h>
  #include <filament/VertexBuffer.h>
  @@ -191,6 +192,17 @@ static void cleanup(Engine* engine, View* view, Scene* scene) {
  }
  #pragma clang diagnostic pop
  +static void preRender(filament::Engine* engine, filament::View* view, filament::Scene*,
  + filament::Renderer* renderer) {
  +
  + // Without an IBL, we must clear the swapchain to black before each frame.
  + renderer->setClearOptions({
  + .clearColor = { 0.0f, 0.0f, 0.0f, 1.0f },
  + .clear = !FilamentApp::get().getIBL() });
  +
  +}
  +
  +
  #pragma clang diagnostic push
  #pragma clang diagnostic ignored "-Wunused-parameter"
  static void setup(Engine* engine, View* view, Scene* scene) {
  @@ -235,8 +247,6 @@ static void setup(Engine* engine, View* view, Scene* scene) {
  view->setAmbientOcclusionOptions({ .enabled = true });
  view->setBloomOptions({ .enabled = true });
  - view->setFogOptions({ .density = 0.2f, .enabled = true });
  -
  if (g_moreLights) {
  g_lights.push_back(em.create());
  @@ -468,7 +478,7 @@ int main(int argc, char* argv[]) {
  });
  }
  - filamentApp.run(g_config, setup, cleanup);
  + filamentApp.run(g_config, setup, cleanup, {}, preRender);
  return 0;
  }
  