UPDATING CACHE WITH SPATIAL DATA

摘要

A method for updating spatial data stored in a cache on a computer readable medium from a source of spatial data is disclosed. The cached data is represented as at least one currency shape which is a geometric shape. The at least one currency shape is compared with an area of interest which is a geometric shape. The comparison is used to determine how to update the spatial data stored in the cache to include spatial data pertaining to the area of interest. Appropriate updates to the spatial data stored in the cache and to the at least one currency shape are made.