Vietnamese director and graphic artist Phuong Mai Nguyen’s first film, “In Waves,” kicked off the independent International Critics’ Week section of the Cannes Film Festival on Wednesday morning, but it also jump-started what it likely to be a running theme at this year’s festival: films that put a spin on biographies and autobiographies.

Examples are on the way from directors as diverse as Pedro Almodovar, James Gray and Bruno Santamaria Razo, not to mention documentaries from Ron Howard and Steven Soderbergh, but Nguyen arrives first with an animated take that has the feel of a collaboration between her and artist AJ Dungo.

The film is based on Dungo’s graphic novel, which used his teen and early adult years as an aspiring artist to pay homage to a girlfriend who asked him to tell their story after she was diagnosed with cancer. Nguyen’s presence could add another layer of distance to that story, except that she seems to have absorbed his style when necessary, though she backs off when the tale needs her own colors.

And yet despite the refracted perspectives, “In Waves” feels of a piece. Using Dungo’s line drawings as a significant aspect of Nguyen’s visual world, it moves past the awkward-teen jokes and tropes to hit home emotionally. It’s less a story about Kristen, the girl who inspired it and to whom it is dedicated, than it is the story of how young artist AJ came to the point where he could document Kristen’s life.

The film starts as the story of AJ, voiced by Will Sharpe in the English version and Rio Vega in the French one. He’s an avid skateboarder and a gifted young artist who decorates his skateboard decks with vivid illustrations, but he’s also shy and timid, particularly around girls and around the ocean in Southern California, where he lives. So you wouldn’t think that Kristen (Stephanie Hsu in English, Lyna Khoudri in French) would be his type, since she’s a passionate surfer and a young woman who’s pretty enough to leave AJ tongue-tied and fumble-fingered.

But they meet cute when he knocks her over at a dance to which his friend had dragged him – and when he goes home and looks at her Facebook profile, the music from composers Oklou and Rob tell us that this is Very Important.

And so it is. Kristen insists on taking AJ surfing (after praying to pioneering Hawaiian surfer Duke Kahanamoku); there’s a late-night rendezvous and a first kiss and before long AJ is making like a skateboarding Gene Kelly as he deliriously rides home in the rain.

But this is the kind of movie where a pain in the leg or a stray cough are never innocent. No sooner do AJ and Kristen succumb to mad young love than she’s been diagnosed with cancer, which leads to an hour of ups and downs, personal and professional complications and lessons learned, not the least of which is that grief is another thing that comes in waves that must be ridden.

The love story isn’t the only tale that “In Waves” tells, with black-and-white sequences cutting in and out of the narrative to detail how early Christian missionaries in Hawaii tried to stop surfing but were thwarted. At Kristen’s urging, this also turns out to be AJ’s thesis in art school, as the lines between Dungo’s and Nguyen’s visual worlds blur.

The director/animator’s style changes and morphs as the film goes on; she uses Dungo’s drawings but also turns waves into bedsheets and a hospital bed into the setting for fantasy. But for all the virtuoso hand-drawn animation, at heart this is an emotional story – and, make no mistake, a major tearjerker of a rom-dram. It’s a work of indie imagination that springs from a graphic novel but also recalls coming-of-age films like “The Fault in Our Stars.” Dungo’s drawings inspired it, but AJ and Kristen’s joy and pain help it connect.