An open-air terrace at cafeteria must be important as a kind of common spaces in campus, and usefulness of such terraces may be affected by the environment. We focused to distance and view angle to the front street, and proposed the “Facing Index on a Point to a Line” (FIPL) as a simple index value to represent how a point such as open-air terrace faces to the street. From observation survey at eighteen terraces in five campuses, we confirmed measurable relationship between FIPL and meal behavior in particular time zone, and discussed further availability of FIPL
