Add padding or a solid background to a Movie Clip with Flash Actionscript AS2

I wrote this little function today to add HTML style padding to a Flash MovieClip. It took a lot of testing to get working but it's actually very straight forward and quite a handy one to have in your function arsenal.

It basically draws a rectangle behind all content in the movie clip and repositions the clip on the Stage. It can also be used to add a solid background behind a given MovieClip. Implementation is a synch:

Please see right hand panel before copying >

/*PARAMS:
mc - the MovieClip to pad
xpad/ypad - size of horizontal/vertical padding in pixels
opacity - optionally make the background invisible or semi transparent
color - optionally change the background colour in hex format 0xFFFFFF
*/
addPadding=function (mc,xpad,ypad,color,opacity){
 if(xpad<0 && ypad>0){return(0)}
 if(color==undefined){color=0xFFFFFF;}
 if(opacity==undefined){opacity=100;}
 
 h=mc._height+ypad
 w=mc._width+xpad
 mc.beginFill(color,opacity);
 mc.lineTo(-xpad, -ypad);
 mc.lineTo(-xpad, h);
 mc.lineTo(w,h);
 mc.lineTo(w, -ypad);
 mc.lineTo(-xpad, -ypad);
 //reposition MC to compensate for new dimensions:
 mc._x+=xpad;
 mc._y+=ypad;
}
//sample usage:
addPadding(myMoveClipName,20,20);

Note: This only works if the content inside the MovieClip is positioned  in the positive axis. In other words the registration point 0,0 must be the very top left of the MovieClip