message: default to openGL when windows does not support VULKAN
diff: @@ -99,8 +99,10 @@ DefaultPlatform* DefaultPlatform::create(Backend* backend) noexcept {
  *backend = Backend::OPENGL;
  #elif defined(IOS) || defined(__APPLE__)
  *backend = Backend::METAL;
  -#else
  +#elif defined(FILAMENT_DRIVER_SUPPORTS_VULKAN)
  *backend = Backend::VULKAN;
  +#else
  + * backend = Backend::OPENGL;
  #endif
  }
  if (*backend == Backend::NOOP) {
  