C-squares
Concise spatial query and representation system (c-squares)
C-squares is an easily implemented method for storage, querying and display of spatial data locations, based on a hierarchical, grid-based representation of the Earth' surface. Source code for encoding, decoding, mapping, etc. is provided via this site. Additional support is available by contacting the system developer, Tony.Rees@marinespecies.org; see also the c-squares home page at http://www.cmar.csiro.au/csquares/ .