What is hidden in 3D image?

A man walked into a bar and ordered a glass of white wine. He took a sip of the wine, then tossed the remainder in the bartender's face.
Before the bartender could recover from the surprise, the man began weeping. "I'm really sorry. I keep doing that to bartenders. I can't tell you how embarrassing it is to have a compulsion like this."
Far from being angry, the bartender was sympathetic. Before long, he was suggesting that the man see a psychoanalyst about his problem.
"I happen to have the name of a psychoanalyst," the bartender said. "My brother and my wife have both been treated by him, and they say he's as good as they come." The man wrote down the name of the doctor, thanked the bartender, and left. The bartender smiled, knowing he'd done a good deed for a fellow human being.
Six months later, the man was back. "Did you do what I suggested?" the bartender asked, serving the glass of white wine.
"I certainly did," the man said. "I've been seeing the psychoanalyst twice a week." He took a sip of the wine. Then he threw the remainder into the bartender's face.
The flustered bartender wiped his face with a towel. "The doctor doesn't seem to be doing you any good," he spluttered.
"On the contrary," the man said," he's done me a world of good."
"But you just threw the wine in my face again!" the bartender exclaimed.
"Yes," the man said. "But it doesn't embarrass me anymore!"