Bay Area choreographer Anna Halprin, who celebrates her 90th birthday in July, is a force of nature. Not the kind that steamrolls everything in its path, but a gently, relentlessly persistent drive, like a wave that starts in the middle of the ocean and lands on Stinson Beach, or a steady, rushing breeze that blows all day from the top of Mt. Tamalpais down to the bay. Breath Made Visible, Ruedi Gerber’s portrait of the artist as an ageless fount, transports us to the woods of Marin County, where the pioneering dancer and choreographer has lived and taught the principles of improvisation and collaboration for decades. The documentary’s physical center is the enormous wooden deck, pitched among the redwoods in their vast yard, which the late landscape architect Lawrence Halprin built for his wife. It serves as studio, performance space, healing hub, refuge, and mecca for those drawn to Anna Halprin’s seer-like spirit and grace. It’s no small feat to make a legend life-size and accessible without dispelling her greatness and mystique, yet Gerber pulls off a delicate tightrope act with relaxed ease. You could say there’s something in the way she moves.