Houston’s tangle of overpasses has grown so massive that a single interchange covers as much area as Siena, Italy. Capturing the city’s “spaghetti bowl” highways from above, Iwan Baan’s camera renders its curves and intersections into a peculiar tactile language. The Rice School of Architecture launched the opening of “Iwan Baan: The Notational Surface,” an exhibition by the acclaimed Dutch photographer, on Sept. 3. Presented as part of the school’s new curatorial program, the exhibition is currently on display at Cannady Hall through Oct. 25.