With all the news of former Disney stars trying too hard to be shocking and tent-pole franchises becoming more bloated and more ridiculous with each new announcement, Joseph Gordon-Levitt’s feature-length directorial debut “Don Jon” is a bright spot in current American pop culture. He and his movie are more impressive within the context of his Hollywood career, which began when he was just a child.

Fun fact: I’ve kept track of Gordon-Levitt’s career since the 1990s. Clarifying fact: I’m not an obsessed fan girl; he just happened to be in some movies, such as “Angels in the Outfield” (1994) and “Treasure Planet” (2002), that I saw back then. When I saw him in “(500) Days of Summer” (2009), I thought, who is this guy? He was so charming, vulnerable and funny. It was that kid from those Disney flicks! Since then, he’s had some duds along the way — seriously, whose idea was it to cast him as the villain in “G.I. Joe: The Rise of Cobra” (2009)? — but Gordon-Levitt has redeemed himself in such films as “50/50” (2011), “The Dark Knight Rises” (2012) and now “Don Jon.”

In the most recent film, Jon (Gordon-Levitt) is a bro from the Jersey Shore: He pumps iron, curses out people as he drives to Mass, keeps his hair oozing with gel and bags ladies every time he goes out with his buds. And he’s addicted to porn. Even after meeting the stunning Barbara (Scarlett Johansson), Jon can’t kick the habit that requires so many tissues. After his relationship with Barbara deteriorates, he finds himself drawn to the odd Esther (Julianne Moore) at his local college.

Even as I congratulate Gordon-Levitt for juggling writing, directing and starring in this production, the movie often has signs of an artist stretched too thinly. What we end up seeing is that Gordon-Levitt the actor succeeds more than Gordon-Levitt the director and the writer.

Although Jon’s character is the focus of the picture, Gordon-Levitt never makes him out to be some idealized version of masculinity. To be frank, I wouldn’t want to be friends with Jon, let alone date him. I was so used to Gordon-Levitt playing nice guys that when I saw him transform into a selfish womanizer who somehow continues to gain the audience’s sympathy, I had an even greater appreciation for his acting abilities.

Gordon-Levitt the director, however, focuses so much on his own acting that his love interests are left with less substantialness. Johansson’s character comes across as the plot-designated battle-ax, turning into a mean girl in the blink of an eye. Moore’s likeable role as an earth-mother type who doesn’t wear makeup, smokes weed and gives Jon advice on how to really connect with women during sex suffers because she does not have enough screen time. She’s the (perhaps predictable) wake-up call that Jon needs. She’s eccentric without becoming one of those Manic Pixie Dream Girls from days of old, but she’s not really in the movie as much as she should be. In fact, the movie screen goes to black just as Esther and Jon reach the peak of their relationship. Imagine if “Silver Linings Playbook” (2012) ended just as Pat and Tiffany were really hitting it off.

But his direction isn’t a total failure. What I did like was the first half of the film’s extreme hyperbole. Ear-splitting dance music punctuates each sexual conquest, parts of women’s bodies glow and people go to watch movies with such titles as “So Hard, So Fast 3D.” This wild take slows down as Jon’s self-confidence breaks down, and the steady camera angles and funny musical cues give way to shaky cam and uncomfortable silence. But even as his direction becomes serious, Gordon-Levitt can’t quite grasp the full depth of the story that he has in his hands. He’s holding back. Not with the pornographic images and unfulfilling sexual encounters with real women — there’s plenty of that — but with the emotional dysfunction on screen. For example, Jon’s family is scary; his father is very close to attacking him, his mother is a borderline idiot and his sister mostly refuses to talk to anyone. Yeah, it’s funny, but there’s a serious problem here. In fact, that statement applies to the whole movie. The movie is almost the lighthearted version of “Shame” (2011), filled with laughter to avoid confronting the core of a bunch of messed-up folks. But while Don Jon lacks “Shame”’s explicit and cold tone, it does have some insight into the many ways people fill in the numb voids in their lives with media.

“Don Jon” may not be the total knockout that I expected it to be, but it stands as a look into the growing talent of a star who has great skill both in front of and behind the camera.