AS3 BitmapData Collision - actionscript-3

Question

I am having a problem with BitmapData Collision detection, my class is not detecting any collision at all
BitmapCollision.as
package com.ipromoweb.demoapp
{
import flash.display.BitmapData;
import flash.display.DisplayObject;
import flash.display.DisplayObjectContainer;
import flash.geom.Matrix;
import flash.geom.Point;
import flash.geom.Rectangle;
/**
* ...
* #author Me
*/
public class BitmapCollision {
private var collides:Boolean = false;
public function check(obj1:DisplayObjectContainer, obj2:DisplayObjectContainer):Boolean {
// obj1
var obj1Rect:Rectangle = obj1.getBounds(obj1);
var obj1Offset:Matrix = obj1.transform.matrix;
obj1Offset.tx = obj1.x - obj1Rect.x;
obj1Offset.ty = obj1.y - obj1Rect.y;
var obj1ClipBmpData:BitmapData = new BitmapData(obj1Rect.width, obj1Rect.height, true, 0);
obj1ClipBmpData.draw(obj1, obj1Offset);
// obj2
var obj2Rect:Rectangle = obj2.getBounds(obj2);
var obj2Offset:Matrix = obj2.transform.matrix;
obj2Offset.tx = obj2.x - obj2Rect.x;
obj2Offset.ty = obj2.y - obj2Rect.y;
var obj2ClipBmpData:BitmapData = new BitmapData(obj2Rect.width, obj2Rect.height, true, 0);
obj2ClipBmpData.draw(obj2, obj2Offset);
var rLoc:Point = new Point(obj2Rect.x, obj2Rect.y);
var bLoc:Point = new Point(obj1Rect.x, obj1Rect.y);
if (obj1ClipBmpData.hitTest(bLoc, 255, obj2ClipBmpData, rLoc, 255)) {
trace("hit");
collides = true;
}else {
collides = false;
}
obj1ClipBmpData.dispose();
obj2ClipBmpData.dispose();
return collides;
}
}
}
And i am calling checkCollision function on a ENTER_FRAME event, the hitTestObject is firing well but the bitmapData Collision is not firing at all.
private function checkCollision():void {
for (var i:int = 0; i < parent.numChildren; i++) {
if (Object(parent.getChildAt(i)).constructor == '[class CollisionTest]') {
if (this.hitTestObject(parent.getChildAt(i))) {
trace('colliding');
if ( _collision.check(Sprite(this),Sprite(parent.getChildAt(i))) ) {
trace('>>>>>>>>>>> perfect hit');
}
}
}
}
}
Any help on this would be greatly appreciated.

Answer 1

I discarded the previous method of BitmapData Collision that i was trying to implement and downloaded a free library called CDK:
https://code.google.com/p/collisiondetectionkit/
it solved all my problems.