1. A system for determining the spatial position and orientation of each of a plurality of bodies, comprising: at least three markers affixed to each one of the bodies in a predetermined, relative geometric relationship, such markers being adapted to emit energy in response to an activation signal and/or to reflect energy impinging thereon from an activatable energy source; an energy detector for detecting the energy emitted by one of the markers and/or the energy reflected by one of the markers; a processor having: a memory, such memory having stored therein the predetermined, relative geometric relation of the markers for each one of the bodies; and wherein the processor compares the stored predetermined geometric relation of the markers for each of the bodies with the energy detected by the energy detector to identify the bodies emitting and/or reflecting the detected energy.