1. A shape object, comprising: a line segment having a length that extends between a first end and a second end, the line segment being flexible into a plurality of positions, each of the plurality of positions used to define a shape of the line segment; an optical fiber integrated along the line segment; an interface connectable to the optical fiber of the line segment, the interface being at the first end of the line segment, the interface including, a first circuit for communicating optical signals to the optical fiber, the first circuit being configured to identify the shape and changes in the shape of the line segment over time; and a second circuit for wirelessly transmitting shape data used to identify the shape of the line segment to a computer that is remote from the line segment, the wireless transmitting of the shape data being one-way to the computer; wherein the first end of the line segment is configured for placement at a known separation to a tracked object that is separately tracked in three dimensional space, the tracked object not being connected to the shape object, the shape data is independent of data defining a position in three dimensional space of the tracked object.