Orlando Boom and Katy Perry are so good right now ... and they're making sure everyone knows it while they laugh it up in the South of France.
The couple had a blast during a fancy yacht party. Based on the optics ... Katy's COMPLETELY over whatever went down in Vegas between Orlando and Selena Gomez.
They were aboard Russian businessman Roman Abramovich's 556 ft. yacht off the coast of Cannes.
It's the kinda luxury that makes it easier to get over stuff.