Stretched bitmaps blurred when rendered using GPU on iOS, how to avoid?

Question

Hi,
in a project of mine (targeting iPhone 4) I'm using pixel art. To show it properly I stretch the bitmap using scaleX/scaleY. However, when rendering using GPU the bitmaps get blurred, ruining the clear pixel art effect that I am after. Rendering using CPU does not blur the bitmaps, but is slower.
Any ideas on how to tell the renderer not to blur bitmaps?
There was a similar questions raised in another thread ( http://forums.adobe.com/thread/866712 ) but it derailed into a benchmarking discussion.
Thank you in advance.

Answer 1

I did not.
Instead I rewrote my code to scale up all my spritesheets in software upon load. Something like this:
var bd : BitmapData = new BitmapData( _spriteWidth * magicScale, _spriteHeight * magicScale, true, 0x0 );
var matrix:Matrix = new Matrix( magicScale, 0, 0, magicScale );
bd.draw( originalBitmapData, matrix );
frames.push( bd );
The variable magicScale is stored behind the scenes in the engine so the rest of the code just acts as if the scene was not scaled.
Note that this solution does not use any blitting techniques, it places bitmaps on the stage and then swaps the bitmapData in them. No off screen buffers, just relying on the GPU.
Works pretty well!