Cracked glass

I am looking for blender script that will make a spider web crack effect you find on windshields. I have looked for tutorials on it, but nothing comes close.

Thanks a lot for your help

. . . the only one way I know is pildanovak!s script from his fracture (crackme) set for blender 2.49. There was one that generates cracks from image. So if you have one with sharp lines try it (or you can draw your own directly inside blender)