Question: I have an array of Sprites on stage and want to now the rectangle that bounds them. I could do a loop and check each element's getBounds() but that could be computationally expensive. Is there a better way to do it?

Answer: 
You could put them all inside a Sprite, and get the bounding box of that sprite.
```
var child:DisplayObject = ...
var parent:DisplayObject = new Sprite();  // should be the parent object.
var bounds:Rectangle = child.getBounds(parent)

```

See: <http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/display/DisplayObject.html#getBounds()>