Изменить BitmapData

[PgeorgyV]

var bd:BitmapData = new BitmapData(100, 100, true, 0x880077ff);
var bd2:BitmapData = new BitmapData(50, 50, true, 0x88ff7700);
bd.draw(bd2, new Matrix(1, 0, 0, 1, 25, 25));
var b:Bitmap = new Bitmap(bd);
addChild(b);