FaceSpace: endo- and exo-spatial hypermedia in the transparent video facetop

The Transparent Video Facetop is a novel user interface concept that supports not only single-user interactions with a PC, but also close pair collaborations, such as that found in collaborative Web browsing, in distributed pair programming and in remote medicine. We recently demonstrated the Vis-a-Vid Facetop prototype as a single-user GUI for manipulating the elements of a traditional WIMP desktop [21]. In this paper we introduce FaceSpace, a Facetop-based hypermedia system that combines structure and functionality of both spatial and ubiquitous hypertext. FaceSpace eliminates camera registration errors due to dynamic object tracking and user self-image feedback. FaceSpace had two forms of linking that combine spatial hypermedia with ubiquitous hypermedia: Like an exo-skeleton provides an organism with structure from without, exo-spatial hypertext has the spatial structure applied over the ubiquity of the user's real-world environment. Endo-spatial hypertext has the spatial structure derived from and attached to the elements of the user's domain. Endo-spatial hypertext is an integral concept in systems that have been classified as ubiquitous hypertext; exo-spatial is unique to FaceSpace in current hypertext systems.