It does not have to be 3D at all. You can achieve this effect by simple animation. Create Graphic symbol let's call it fragment, inside draw few frames of changing and zooming polygon. Then you create another Graphic symbol, place multiple fragments in it and play a bit in timeline so they move and scale gradually, not all at once.. that's it.
You don't need real 3D engine because there are no textures, no shades. It's just a bunch of vectors drawn that well that you feel like it's 3D.
Thanx a lot peter..
this website is also using a mechanism which is similar..does dis also working on the mechanism of frame by frame animation????
I'm not sure if they use some automated sowtware for generating vector animations but yeah, you can achieve just that by Graphic symbols and careful animation. Including 3D engines for that simple tasks would be overkill, unnecessary cpu load.