Cops say the "Avatar" star was at Vortex, a restaurant in Atlanta, when he was refused entrance because people at the door felt he was too intoxicated ... this after he got into an argument because he didn't have the ID required to get inside the club.

According to the police report, a witness told cops Worthington became disorderly. He allegedly pushed the doorman twice and the doorman responded by pepper spraying him and putting him in cuffs until the cops arrived.

We're told the entire incident is on surveillance video.

Worthington was charged with disorderly conduct -- fighting.