6.1 Summary of Results

Contents

6.1 Summary of Results

The central focus of this thesis is represented by the following three steps: a current state analysis of Free web mapping applications, which leads to the definition of the term Smart Map Browsing, as well as the implementation of a selected Smart Map Browsing feature.

The current state analysis investigated the usability of twelve selected web mapping applications. As expected, Google Maps (the lone proprietary representative) proved to be a cutting-edge application. The analysis also revealed an impressive performance by OpenLayers
As a general summary it can be said that in terms of usability, the tile-based applications convince with their no-delay map panning and dynamic tile assembly. Combined with a zoom bar these applications have an already large lead in terms of usability compared to conventional web mapping applications.
An innovative and so far novel interactive extension was provided by p.mapper's continuous zooming feature, which shows great potential for the further development of web mapping applications.
The majority of analyzed applications showed definite weaknesses because of missing zoom options with mouse wheel, double-click or keyboard commands. In addition, the static zoom performance seen in many overview maps left a decidedly negative impression with regards to usability.
Before submission, all analysis results of this thesis were re-checked and updated if required.

This thesis also developed and defined the term Smart Map Browsing. A definition was developed on the basis of the ISO usability standards. The characteristics of Smart Map Browsing were derived from the results of the current state analysis; they outline the current state of the technology of Smart Map Browsing. The characteristics serve as guidelines on how web mapping applications could be conceptualized and developed for a high level of usability. This includes intuitive, self-explanatory GUI components as well as pan/zoom that performs to expectations after interacting with these elements. Smart Map Browsing intensity describes the degree of usability. When a web mapping application displays all of the listed properties, it is considered a high-grade Smart Map Browsing application. On the other hand, if the application features fewer of these properties, it has a lower Smart Map Browsing quality.
The thesis highlighted the most significant features of Smart Map Browsing as well as their future potential. The result: the performance of (client-side) tiling can be significantly improved by (server-side) tile caching, as shown by the implementation of TileCache. An important factor for zoom depth orientation is the zoom bar. The use of animated zooming und panning shows great potential, as it creates an entirely new »navigation experience« for the user. These characteristics along with their potentials are continuously updated and developed through new technology, and they will further shape the development of Smart Map Browsing.

The third phase of this thesis consisted of the implementation of the Smart Map Browsing feature animated zooming into OpenLayers. Summarizing, almost all stated Must-Have and Should-Have requirements were implemented, with the exception of active overlay scaling and achieving full support for all layer types. Performance issues were the main problem encountered during implementation - the next section discusses the resulting open issues.
The developed feature expands the current OpenLayers-API. Through the Build Profile of OpenLayers it is possible to combine selected API classes into a single JavaScript file. This file can then be integrated into any web mapping application. As a result, this thesis was successful in achieving its original objective of finding a universally valid solution.
The implementation results are summarized in eight patches and are currently undergoing the review process by OpenLayers developers. The patch for the improvement of the panning keyboard control has already been accepted without modifications and has been released as part of OpenLayers Version 2.4 RC2 in April 2007. The integration of animated zooming and panning is planned for Version 2.5 which is scheduled to be released in the fall of 2007.

6.1 Summary of Results

Contents