Two French films - one sleepy, one freewheeling

The slow, sleepy style of French director Bertrand Tavernier has been a constant in movies as different as ''The Clockmaker'' and ''Coup de Torchon,'' to name an early project and a recent one. But his aggressively laid-back approach has never been so appropriate as in his new picture, ''A Sunday in the Country'' - where for the first time Tavernier matches the absence of storytelling energy with the absence of a story.

The main character is an elderly painter, gently played by Louis Ducreux, a stage director turned movie actor.

The film takes place during what is probably the last sunstruck day in his genial, contented life. Nothing much happens except a visit from members of his family, whose busy pleasures and pains contrast poignantly with his inner peace. At the end they bustle home again, leaving him alone with his artworks and his thoughts, which are all a person of his acquired wisdom could ask.

This film, glowingly photographed by Bruno de Keyzer, and featuring Gabriel Faure music, won Tavernier the ''best director'' prize at the 1984 Cannes festival. It's a lovely film to look at and listen to, and if it were as passionate as it is controlled, it might have been an exciting emotional journey as well.

But the filmmakers are so fascinated with shimmering surfaces that they never probe the profundities that lie beneath. ''A Sunday in the Country'' is an eye-dazzling, amiable, exactingly crafted drama that unfortunately dodges the deeper implications of its own engaging subject: the summation of a life, and what that life has meant to others and itself.

The film is rated G, though its subject matter is unlikely to engage young children. 'A Nos Amours'

Maurice Pialat, another French director, has developed a loose narrative style that mirrors the freewheeling lives of his characters, who are often young and unsettled. ''A Nos Amours'' is an excellent example of his work, chasing breathlessly after the exploits of a teen-age girl on the brink of sexual and emotional maturity. It's also his most successful picture to date, having won the Prix Delluc and the Cesar, two major French prizes.

The drama is fairly conventional when focusing on the heroine's love affairs, which bring few surprises despite a lot of twisting and turning. But things come alive when Pialat focuses on family life, setting up a snarled web of emotional tension in a bourgeois apartment that seems about to explode from so many conflicts raging away, all hopelessly irrational yet supercharged with energy.

The director provides an in-person center of gravity by playing the teen-ager's father in a carefully nuanced portrayal. The other performances follow his lead, although none reach the same level of excellence.