Most of you probably have seen the code below. I just can't figure out what it does exactly... and that makes it kinda hard to implement...

Code:
if (walls.hitTest(getBounds(_root).xMax, _y, true)) {
trace('hit');
}
if (walls.hitTest(getBounds(_root).xMin, _y, true)) {
trace('hit');
}
if (walls.hitTest(_x, getBounds(_root).yMax, true)) {
trace('hit');
}
if (walls.hitTest(_x, getBounds(_root).yMin, true)) {
trace('hit');
}
Now what I understand is that it does a hitTest of something on a mc called walls. So if the something hits walls you'll get the alert 'hit'. I believe the _x and _y values are the ones of the something.... and true is set so that it tests on shape in stead of boundry, right? But what does: getBounds(_root).yMax and so on do? Please explain...

Cheers