tener('mouseup', function(e){
		slider_down[no] = false;
	}, false);

	slider.addEventListener('mousedown', function(e){
		slider_down[no] = true;
		var canvas_rect = slider.getBoundingClientRect();
		position_slider(no, e.clientX - canvas_rect.left);
		on_slide(slider_lb[no], slider_ub[no]);
		draw_slider(no);
	}, false);

	slider.addEventListener('mousemove', function(e){
		if(slider_down[no] == true){
			var canvas_rect = slider.getBoundingClientRect();
			position_slider(no, e.clientX - canvas_rect.left