Using again Perlin noise, we can have a very nice fire effect for our flash objects.
Time ago, I found a experiment with particles on the site "asluv.com".
I like it, but it was a little slow, so I decide to change the code a little, and just avoiding the use of sprites, I got a great improvement on the speed.
This AS3 experiment uses a BitmapData to determine whether the particles should change their speed in function of the background color of the bitmap.
There is a GlowFilter and BlurFilter applied to the particles, to create a nicer visual result.
Playing just with the filter, we can get very diferent and nice result.
In this experiment with actionscript 3.0,
I'll be playing around with 100.000 to 300.000 particles at a time.
Create particles is really easy in actionscript, and I'm always doing lots of experiments with lots of sprites or movieClips, and then move then around.
But the problem is that it doesn't take long to have so many particles on the stage that Flash can no longer handle it.
In fact, depending on the code you use for interacting btween this particles, it really doesn't take that many Sprites on the stage at all for Flash to start falling apart.