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IE Vol. 8 
VISUALISATION USING GAME ENGINES 
Dieter Fritsch, Martin Kada 
Institute for Photogrammetry (ifp), University of Stuttgart, Germany 
Geschwister-Scholl-Strasse 24D, D-70174 Stuttgart 
firstname.lastname(g)ifp.uni-stuttgart.de 
Commission V, WG 6 
KEY WORDS: Visualisation, Virtual Reality, Real-Time, GIS, Modelling 
ABSTRACT: 
Geographic Information Systems (GIS) and Computer Aided Facility Management-Systems (CAFM) are currently undergoing the 
transition to storing and processing real 3D geospatial data. Applications for this type of data are, among others, location based 
services, navigation systems and the planning of large-scale construction projects. For presentation purposes and especially when 
working in the field, powerful visualisation systems are needed that are also capable of running on mobile devices like notebooks, 
personal digital assistants (PDA) or even cell phones. In such application areas, the free movement of the viewer's position and the 
interaction with the data are of great importance. Real-time visualisation of 3D geospatial data is already well established and also 
commercially successful in the entertainment industry, namely in the market of 3D video games. The development of software in this 
field is very cost-intensive, so that the packages are often used for several game products and are therefore universally applicable to a 
certain extend. These so-called game engines include not only visualisation functionality, but also offer physics, sound, network, 
artificial intelligence and graphical user interfaces to handle user in- and output. As certain portions or sometimes even the whole 
engine are released as open source software, these engines can be extended to build more serious applications at very little costs. The 
paper shows how these game engines can be used to create interactive 3D applications that present texture-mapped geospatial data. 
The integration of 3D data into such systems is discussed. Functionality like thematic queries can be implemented by extending the 
internal data structures and by modification of the game's accompanying dynamic link libraries. 
1. INTRODUCTION 
Since the time computer graphics has been introduced, the 
demands for visualisation techniques have grown 
continuously. Today, the visualisation of three-dimensional 
worlds seems to be a demanding task requested by many geo- 
related disciplines. This has led to Scientific Visualisation, 
which is associated with solving visualisation problems of all 
kind (McCormick, DeFanti and Brown, 1987). It offers 
algorithms, software packages and advanced interactive tools 
(such as data gloves and other haptic interfaces) for graphics 
workstations, high end rendering machines and CAVE 
environments (see also Fritsch, 2003). 
Complementary are the developments in the computer game 
industry that has been developing game engines with 
amazing 3D computer graphics capabilities since the early 
1990s. Due to the increasing interest in the consumer market, 
tremendous progress can be observed in the hardware and 
software. Game engines are powerful software packages that 
efficiently use rendering pipelines, special data-structures and 
speed-up techniques to visualise texture mapped 3D objects, 
scenes and 3D worlds in real-time (see e.g. Harrison, 2003). 
These software packages run nowadays on every commodity 
PC and 3D games already make their way on PDAs and even 
cell phones. The overall question is how to make best use of 
available technology to make the right application. 
Only few large projects use sophisticated hardware and 
Software. For many 3D mapping applications, only 
commodity hardware and software is available. But even the 
daily user of computer graphics still aims at high quality 
visualisation at low costs. Game engines might be the missing 
part for realising visualisation software for gco-related 
applications. The rendering performance and quality 
continuously increases as the game industry develops and 
implements new visualisation technologies. And many of the 
last generation engines or game-related libraries are now 
available for little or even no cost in the form of open-source 
software. The following sections will focus on both indoor 
and outdoor visualisation, will introduce some assorted game 
engines and show prototypical applications that have been 
built upon them (see e.g. Figure 1). Another aspect will be 
  
Figure 1. Indoor visualisation showing a workspace at the 
Institute for Photogrammetry (ifp) rendered in 
real-time by the Quake 3 Arena game engine.