Primitive-based Construction Theory for Diagrams in Thematic Maps

Abstract

To enhance the variety of map symbols and to develop new symbol types, a fundamental understanding of the map symbol construction process is mandatory. Current construction theories focus on diagrams without taking georeferencing or interactivity into account. This paper presents a new methodology for the creation of two-dimensional geometric symbols and diagrams for the application in thematic maps. In this context, 49 diagrams found in cartographic literature were analysed and classified regarding their construction properties. As a result of this research, diagrams can be defined using cartographic primitives which are arranged according to six arrangement principles. Since the variation of the primitive's size according to the data values follows a certain geometric direction, each diagram can be explicitly defined based on the three construction properties 'primitive', 'arrangement principle' and 'data direction'.