Jamie Foxx is a cool customer onscreen … but, he lost it on some festivalgoers at an event put on by his teenage daughter after GloRilla was apparently hit with something while performing.

Video is circulating online from SKVLK FEST — an annual Halloween/birthday party Jamie’s daughter Anelise helped start when she was 13, that’s now in its fifth year — at Foxx’s home in Thousand Oaks, where Jamie’s onstage demanding to know who threw an object.

He uses some NSFW language after the incident … calling people out for throwing something in his house — and demanding better from everyone in the crowd.

Many online are saying Foxx is reacting to a projectile hitting GloRilla … though no videos of that moment have emerged online yet. We’ve reached out to Jamie and GloRilla for more information.

Foxx posted about the event … but not the unfortunate incident — instead simply calling the event “iconic” and telling his daughter he’s proud of her.

It’s not surprising Jamie popped off at the crowd BTW … remember, late last year Jamie was hit in the mouth by a glass during his birthday dinner.

Members of the “Jackass” production team were projecting a penis onto Jamie’s table with a laser pointer when he confronted them … and a glass was heaved at him, which he says cut his face and required stitches.

The L.A. County District Attorney’s Office declined to prosecute the case.