46. The computer apparatus recited in claim 45, wherein: wherein each SELECTOR node of said SELECTOR NODES includes data the specifies coordinate values that describe the region defined by said each SELECTOR node; the step of receiving a request includes receiving a request from the client that specifies coordinate values; and the step of selecting includes selecting SELECTOR nodes based on the coordinate values specified by said Selector nodes and said request.
45. The computer apparatus recited in claim 44, wherein: the description includes a plurality of SELECTOR nodes in the description, wherein each of the SELECTOR nodes defines a particular region from said regions; step (B) further comprises the steps of: sensing when a virtual position of the client in the image moves so that the field of view encounters a new region among the regions; and selecting one of the SELECTOR nodes associated with the new region.