Efron, 26, who is said to be undergoing alcohol de-addiction treatment, enjoyed an evening at a bowling alley in California and later some drinks at a nightspot with the 'Twilight' star, 28, reported E! News.
"Zac was seen goofing around and Rob was not even trying, skipping his turn at one point. When they left some of the friends smoked cigarettes, while they all just laughed and talked," a source said.
"Rob and Zac both looked good and happy. Rob showed Zac something on his cell phone and they both started laughing. They were in really good moods," the source added.