class FrameWatcher { public: FrameWatcher(); ~FrameWatcher(); void do_tick(); private: float get_elapsed_time(); float step_size = 0.0166f; double frame_time = 0.0; double elapsed_time = 0.0; double delta_time = 0.0; double accumulator_time = 0.0; double current_time = 0.0; };