Design and development of the electronic atlas of Beijing
DING Lin,LIU Yue,WANG Quan ke (Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China)
Electronic map is the main method of visualizing geographical information. Following the popularization of all kinks of digital maps and web maps products, the design of the electronic map has become more and more important and constituted one of the key study fields in geo science and modern cartography. In study on design of electronic map, “design of user interface”, “presentation of three dimension land sight”, “application of multiple media”, “conflict of figure”, “dynamic annotation”, “interactive function of screen map” are important and unavoidable problems. Even though the electronic map is becoming more and more popular, these problems still need to be further studied. The paper summarizes and analyses the issues concerning electronic map design, discusses the theory of electronic map design, puts forward suitable method of data organization and technique of “multiple presentation”, and thus realizes “dynamic annotation” and efficient “space index” method. It provides basic services for better viewing: zooming and panning, rotation, virtual movement of the observer over 3D graphics, enlarging selected elements of graphics, etc. This system realizes the integration of graphic data and attribute data, so graphical presentation reflects the results of querying a database and is immediately updated when the user changes the query conditions. There are several linked displays of the same data set. The user selects some objects or data subsets in one of the displays, and the corresponding objects or data are highlighted in all the displays. The dynamic manipulation techniques available in this atlas are illustrated not only with pictures but also with “live” maps. In the end, based on the practice of the “Electronic Atlas of Beijing”, the paper discusses the design of interface and map function of the electronic atlas and several important issues on design of electronic maps are discussed in detail..