void RenderingSystem::attachController(unsigned int EntityKey, EntityID entity)
{
	// layer is an enum/int
	auto layer = mProperties.get<P::Visible>(entity)->layer;
	auto controller = new RenderingController(entity, mProperties);
	// mControllers is an array of maps
	mControllers[layer][EntityKey] = std::unique_ptr<RenderingController>(controller);
}