Figure 1. An n-Vision world that encodes a function of five variables as a hierarchy of graphs. The height field in the inner world encodes the function for constant values of x3, x4, and x5, determined by the position of the inner world's origin relative to the outer world. As the user translates the inner world, n-Vision updates the height field. A one-dimensional graph, called a dipstick tool, provides a precise readout at one point of the height field.