I\'m learning ActionScript/Flash. I love to play with text, and have done a lot of that kind of thing with the superb Java2D API.
One of the things I like to know i
Richard is on the right track, but BitmapData.getColorBounds() is much faster and accurate... I've used it a couple of times, and optimized for your specific needs its not as slow as one might think.
Cory's suggestion of using flash.text.engine is probably the "correct" way to go, but I warn you that flash.text.engine is VERY (very!) hard to use compared to TextField.