Perhaps I should have said "threshold_height". threshold_height = bottom_of_pipe_height + 10 pixels; // or something if (current_height < threshold_he

Perhaps I should have said "threshold_height". threshold_height = bottom_of_pipe_height + 10 pixels; // or something if (current_height < threshold_height) flap else don't flap If you never flap when above the threshold, you will not hit the top.