I'm still tryin to find out Vigga!

Somebody please explain this joke/insult to me. After the guy bumps into Ricky and says *beep* you lookin at N*gga!?" and Ricky replies, "I'm still tryin' to find out, Vigga!"

Clearly this is meant as an insult of some sort, and clearly he said "Vigga" or "Figga" and not "N*gga". I have never heard this said anywhere in any movie or any rap song, and I grew up around alot of black people, and I've never heard anyone say this to anybody else.