Comments on: The trouble with getBounds()

By: y_nk

y_nk — Thu, 22 Apr 2010 09:06:31 +0000

hello,

i tried this with 2 squares named “test” and “masque” in the IDE :

test.mask = masque;
test.scrollRect = new Rectangle(0, 0, 20, 20);

var real:Rectangle;

real = test.getRect(test)
.intersection(test.mask.getRect(test))
.intersection(test.scrollRect);

trace(real); (x=10, y=10, w=10, h=10)

i don’t know if it looks like what you want

By: Thomas

Thomas — Wed, 27 Jan 2010 00:04:18 +0000

Hi,
tkx for your code.
I took the BitmapData approach from colin and made a function that works with DisplayObject whose upper left corner is not at 0,0. It returns a Rectangle object too.

http://blog.open-design.be/2010/01/26/getbounds-on-displayobject-not-functioning-properly/

By: getBounds() on DisplayObject not functioning properly | Down the Rabbit Hole

Tue, 26 Jan 2010 21:39:07 +0000

[...] During my search, I found a post from David Barlia: http://studio.barliesque.com/blog/2008/10/the-trouble-with-getbounds/ [...]

By: matt

matt — Thu, 15 Oct 2009 08:13:42 +0000

this saved me a lot of time and frustration, thanks David!

By: barliesque

barliesque — Mon, 10 Nov 2008 06:18:52 +0000

Thanks for dropping by Colin.

That’s an approach to the problem I hadn’t considered. Looks like a pretty reliable method without the problem of having to reconstruct masks in code. Nice! I only wonder if the performance hit of pre-rendering the MovieClip makes it usable on a frame-by-frame basis.

By: colin

colin — Sun, 09 Nov 2008 05:03:40 +0000

hey david,
you could use a bitmap to check the real dimensions. too bad actionscript doesn’t provide something built-in. here’s a simple example:

package {
  import flash.display.*;
  import flash.geom.ColorTransform;
  import flash.geom.Rectangle;
  import flash.text.TextField;
 
  public class Test extends Sprite {
    private var t:TextField;
    private var m:Shape;
 
    public function Test () {
      t = new TextField();
      t.background = true;
      t.backgroundColor = 0x00FF00;
      t.text = "Hi there";
 
      m = new Shape();
      m.graphics.beginFill(0x000000);
      m.graphics.drawRect(0, 0, 15, 25);
 
      addChild(t);
      addChild(m);
      t.mask = m;
 
      trace(t.height);  // 100 (not 25)
      trace(getVisibleHeight(t));
    }
 
    public function getVisibleHeight (o:DisplayObject):Number {
      var bounds:Rectangle;
      var bitmapData:BitmapData = new BitmapData(o.width, o.height, true, 0);
      bitmapData.draw(o, null, new ColorTransform( 1, 1, 1, 1, 255, -255, -255, 255 ) );
      bounds = bitmapData.getColorBoundsRect( 0xFF000000, 0xFF000000 );
      bitmapData.dispose(); 
      return bounds.y + bounds.height;
    }
  }
}