Kobe Bryant On a Big, Fat Boat, Keeps Shirt On

Kobe Bryant went from "skins" to "shirts" in Italy on Wednesday -- keeping covered up on a boat in Portofino after being body shamed the day before.

The ex-NBA superstar was mocking himself about the topless pics that surfaced on Tuesday -- jokingly calling himself "Mamba Thick" and vowing to get shredded again in 30 days ... not that he really needs to.

Still, he didn't look too concerned during Wednesday's family boat trip -- smiling with Vanessa and his 3 daughters ... and snapping photos from a real deal camera (instead of an iPhone).

Say "cheese" ... even if it's not on the diet anymore.