    # File lib/rubygame/old_rect.rb, line 563
            def normalize!
                    if self.at(2) < 0
                            self[0], self[2] = self.at(0)+self.at(2), -self.at(2)
                    end
                    if self.at(3) < 0
                            self[1], self[3] = self.at(1)+self.at(3), -self.at(3)
                    end
                    self
            end