The WP UI is currently intended to provide easy access to a core set of functionality for a heterogeneous user population. This core functionality is focused on 1) composing spatial search queries; 2) displaying spatially-indexed materials, in both raster and vector format; 3) browsing search results; 4) allowing user-configurable defaults and options; 5) efficiently retrieving data items in various native formats.
The RP supported the first three of these functions, using an implementation based on the GIS software package Arcview [4]. In adapting the system to the WWW environment, however, and in augmenting the functionality of the RP, a number of significant issues arise.