Kólbl, Otto 
  
CONCEPTION OF AN INTEGRATED 3D-GIS 
FOR PRIMARY DATA ACQUISITION AND DATA MANAGEMENT; 
APPLIED TO AN INVENTORY OF HISTORIC MONUMENTS 
Otto KÓLBL*, Faissal CHERRADI**, Hans HOSTETTLER*** 
*Professor, Institute of Photogrammetry, Ecole polytechnique fédérale de Lausanne (EPFL), Switzerland 
Otto.Koelbl@epfl.ch 
**CERKAS, Ouarzazate, Morocco 
*** Architect, Bern, Switzerland 
h t hostettler(Qbluewin.ch 
KEY WORDS : GIS, Photogrammetric data acquisition, 3D-modelling, Virtual reality. 
ABSTRACT 
On the example of the inventory of the historic monuments of the south of Morocco, one shows up 3D data acquisition 
and 3D modelling. The work is part of an inventory of these monuments and the information is integrated in an infor- 
mation system allowing flexible management of the data. The tools used concern also the management of photographic 
views with the special ‘Engineering Link’ and the management of detailed descriptive files beside the extensive use of a 
relational database. 
1. INTRODUCTION 
The application of Geographic Information Systems to various inventory tasks based mainly on photogrammetric data 
acquisition is becoming a routine work. However most GIS are 2D organised and do not allow an extension to 3D 
object modelling. Whereas an inventory of a built-up area, including information on the facades is difficult to imagine 
on a system based only on 2D. These applications require rather 3D modelling, the inclusion of elements of virtual 
reality and the visualisation of facades and of various other photographic documentation. The article presents the con- 
ception of an integrated 3D-GIS including elements of virtual reality and Netscape elements beside the organisation of 
attribute data in a relational data base. The concept of this 3D GIS was developed for the inventory of the historic 
monuments of the Dräa Valley of Southern Morocco. This project represents a collaboration between the Institute of 
Photogrammetry of the EPFL, in Switzerland, the architect Hans Hostettler, Bern, Switzerland, and the “Centre de 
Conservation et Réhabilitation du Patrimoine Architectural des zones Atlasique et Subatlasique“ (CERKAS) of 
Morocco. 
2. 3D MODELLING AND VIRTUAL REALITY 
In order to obtain a high degree of vividness, one urges more and more that information systems present beside flat 
maps also 3-dimensional presentations. However, the incorporation of the virtual reality requires the use of 3D-capable 
information systems. AutoCad, MicroStation or ArcView show certain possibility in this respect. Of course, the possi- 
ble effects remain still limited like the use of avatars (artificial human beings) and the independent movement of one or 
several objects which would require the use of specific software products like SoftImage, 3D-Studio and others. How- 
ever, these specific products of virtual reality cannot be connected with a relational database. It is however always pos- 
sible to make use of software of virtual reality by using special interfaces. Another possibility in order to work with the 
effects of virtual reality is the use of the Virtual Reality Modular Language (VRML). Also in this case the data have to 
be exported from the information system and are then presented by a simple browser. However, all modifications of the 
basic set of data requires a repetition of the data transfer and the data visualisation. Consequently, it has great advan- 
tages to limit themselves to a 3D-capable CAD system which also allows a possibility for 3D visualisation which is 
possible with the above-mentioned systems like AutoCad, MicroStation or ArcView. 
2.1 Integration of raster data 
Beside geometric representations, there are also images like photographic views, aerial photographs and orthophotos 
but also hand-drawn sketches which play an important role for vivid presentations in architecture and civil engineering. 
As for the presentation of the information, but also concerning data acquisition, one requires in general that these 
images can be combined with geometric presentations. 
  
446 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B5. Amsterdam 2000. 
  
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