While my heart bleeds for the Adobe decision of “end-of-life” of Flash in 2020, I am still playing with AIR and GPU shaders.
Hopefully Adobe will not be so dumb to condemn the wonderful AS3+Starling+AIR, still great solution for Indie game developers.
An introduction to AGAL instructions by Jackson Dunstan:
Conditional AGAL instructions:
http://volgogradetzzz.blogspot.it/2012/12/agal-condition-operators-in-flash.html