I decided to make something similar for a mobile game, and meanwhile I am showing you the Stencyl prototype:
Click and drag the mouse anywhere to create an influence area which will push the stars. If you don’t see the stars, probably you’ll have to reload the page.
About the source code, some readers told me it’s a bit senseless to place behaviors screenshots, because they can’t cut/paste them, so I decided not to post behaviors screenshots unless there are core features to show you.
So I released the prototype on StencylForge as Public Domain, search for “SnowFlakes” to find it, and I am also giving you the zipped folder for you to unzip it into your Stencyl’s