case "bt_brightness":
temp_angle=bt_brightness.rotation;
var an:Number=Math.atan2(mouseY-bt_brightness.y,mouseX-bt_brightness.x);
var a:Number=an*(180/Math.PI);
start_angle=a;
addEventListener(Event.ENTER_FRAME,onEnterFrame);
stage.addEventListener(MouseEvent.MOUSE_UP,onMouseUpHandler);
break;
case "bt_contrast":
temp_angle=bt_contrast.rotation;
var an:Number=Math.atan2(mouseY-bt_contrast.y,mouseX-bt_contrast.x);
var a:Number=an*(180/Math.PI);
start_angle=a;
addEventListener(Event.ENTER_FRAME,onEnterFrame1);
stage.addEventListener(MouseEvent.MOUSE_UP,onMouseUpHandler);
break;