DESIGN AND IMPLEMENTATION OF
AN OBJECT-ORIENTED GIS SOFTWARE
Jianya Gong
Deren Li
National Key Lab for Information Engineering in Surveying, Mapping and Remote Sensing
Wuhan Technical University of Surveying and Mapping
39 Luoyu Road, Wuhan, 430070, P.R. of China
Commission IVIV
KEY WORDS:
ABSTRACT:
GIS, Database, Software, Design, Model, Integration
This paper discusses object-oriented technology in GIS from geographic real world, through the conceptual model
of geographic phenomenon, logical model of geographic database, and software modeling of geographic information
system. The object-oriented semantic models are used for describing the spatial phenomena and objects. An object-
oriented spatial database management system (GeoDB) is designed according to the object-oriented logical data model,
and an object-oriented GIS software (GeoStar) is developed based on the GeoDB and C++. Some techniques on object-
oriented analysis, object-oriented system design, and system implementation are introduced in this article.
1. INTRODUCTION
Object-oriented technology has come into fashion in computer
science and technology. Object-Oriented
Programming Language (OOPL), Object-Oriented System
Analysis (OOA), Object-Oriented System Design (OOD),
Object-Oriented Interface (OOI), Object-Oriented Database
Management System (OODBMS), Object-Oriented
Geographic Information System (OOGIS), Object-Oriented
Knowledge Engineering (OOKE) and so on. We have seen
that object-oriented approaches have made great progresses.
It includes
Proprietary object-oriented systems have continued to develop
in the intervening years. The programming language C++ is
very popular and now well-established as a standard object-
oriented language. Commercial object-oriented database
management systems (OODBMS) including ONTOS,
Gemstone, ObjectStore, O2 and etc. have become easily
available, although they are still not in use on large-scale. In
GIS, research on the application of object-oriented ideas to
GIS has come a long way in the past few years, from
pioneering work by Egenhofer and Frank (1987), through the
explorations done by Worboys(1990), Gong(1990), etc., to
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current work on conceptual models, logical data models,
system modeling and implementation. The object-oriented
approach has been used to design and implement systems such
as letergraph's TIGRIS, Smallworld GIS, Laser Scan's GAE
and GeoStar (Gong, 1994) developed by Wuhan Technical
University of Surveying and Mapping in China. As yet there
are few proprietary GIS that have object-oriented features, but
those that do exist have been highly successful for specialized
markets and it is likely that more commercial object-oriented
GIS will follow(Worboys, 1994).
A GIS is a multi-faceted entity that goes through several
processes in its life-cycle (see figure 1, Worboys, 1994) from
conception through design and implementation to use. The
object-oriented approach can be applied at all of these
different levels and has a slightly different meaning at each.
From the beginning, the object-oriented conceptual model can
be used for object analysis and system analysis. Following
analysis comes design, which is responsible for deriving a
logical data structure and a system. The procedure from object-
oriented conceptual model to object-oriented logical data
structure is natural and the result of object-oriented analysis is
useful to object-oriented design. The translation of the design
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B4. Vienna 1996