title: hitTestPoint() not testing for collisions correctly
body: <p>I'm writing a game and it has enemies and bullets. When a bullet hits an enemy, I want to destroy the enemy and the bullet. I'm using the <code>hitTestPoint()</code> method to test if a bullet has hit an enemy. Here's the code in my game loop:</p>
  
  <pre><code>for each(var bullet:Bullet in this.bullets) {
      for each(var enemy:Enemy in this.enemies) {
          if(enemy.hitTestPoint(bullet.x, bullet.y)) {
              trace("hit");
          }
      }
      bullet.update();
  }
  </code></pre>
  
  <p><code>this.bullets</code> and <code>this.enemies</code> are both arrays containing objects for bullets and enemies. Here's those two classes:</p>
  
  <pre><code>package com {
      import flash.display.MovieClip;
      import flash.display.Stage;
  
      public class Bullet extends MovieClip {
  
          private var stageRef:Stage;
          public var speed:Number = 10;
  
          public function Bullet(stage:Stage) {
              this.stageRef = stage;
          }
  
          public function update() {
              this.x += Math.sin((Math.PI / 180) * (360 - this.rotation)) * this.speed;
              this.y += Math.cos((Math.PI / 180) * (360 - this.rotation)) * this.speed;
          }
      }
  }
  </code></pre>
  
  <p>--</p>
  
  <pre><code>package com {
      import flash.display.MovieClip;
      import flash.display.Stage;
  
      public class Enemy extends MovieClip {
  
      public var speed:Number = 4;
      private var stageRef:Stage;
  
      public function Enemy(stage:Stage) {
          this.stageRef = stage;
          this.x = this.stageRef.stageWidth / 3;
          this.y = this.stageRef.stageHeight / 2;
      }
  
      public function update() {
  
      }
  }
  </code></pre>
  
  <p>}</p>
  
  <p>The problem is, <code>hitTestPoint</code> only returns true if both the x and y values of bullet and enemy are the same, rather than if the two movie clips overlap. This leads to bullets going right through enemies but it not registering as a hit. Perhaps I'm missing a bounding box?</p>
  
  <p>Is there a way I can make <code>hitTestPoint</code> return true if the bullet hits the enemy at all rather than only if the bullet and enemy co-ordinates are the same?</p>
  
  <p>Thank you!</p>