VISUALIZATION OF 3D SPATIAL DATA FOR CITY PLANNING
M. Kosmatin Fras!”, M. Janezié!, D. Kreub?, T.Fius?
' Geodetic Institute of Slovenia, Jamova c. 2, SI-1000 Ljubljana, Slovenia - mojca.fras@geod-is.si, miran.janezic(@geod-is.si
“Navidez Ltd, Teslova 30 , SI-1000 Ljubljana, Slovenia - darij.kreuh@navidez.com, tadej.fius@navidez.com
Commission VI, WG VI/3
KEY WORDS: photogrammetry, 3D city models, urban planning, visualization
ABSTRACT:
There is an increasing need for three-dimensional (3D) data in urban areas. This data is useful for various applications such as
visualization for planning purposes or simulations for environmental studies. Many different kinds of data are usually already
available, thus it is only a question of a technique how to integrate different data into one system and how to visualize them.
Especially, when data is acquired with photogrammetric methods it is already in 3D form. Photogrammetry is useful and from many
aspects the optimum technique for bulk data acquisition in topographical applications. In the paper, the approaches of data
integration and data visualisation are presented, demonstrated on examples of the municipality of Ljubljana, the capital of Slovenia,
and town BreZice. Topographic and other spatial data that act within the urban context make use of the 3D information system
presented in the paper for complex data visualization and simulation.
1. INTRODUCTION 2. BUILDINGS IN 3D CITY MODEL
Topographic spatial data could nowadays be visualised in three- 2.1 Level of details
dimensional forms more easily than ever. Common computer
tools could be useful for this purpose or specific applications ~~ Buildings are one of the most characteristic elements in a 3D
could be developed on different platforms. There is an city model. Buildings could be represented with different levels
increasing need for three-dimensional (3D) data in urban areas. Of detail. The first level is representation of buildings like
This data is useful for various applications such as visualization blocks (Figure 1).
for planning purposes or simulations for environmental studies.
Many factors (ie. knowledge, equipment, techniques,
availability of data, finances) influence the decision how to
integrate different 3D data into one system. We may only
visualise the existing data or we can use 3D models like a
spatial information system.
Photogrammetry is useful and from many aspects the optimum
technique for bulk data acquisition in topographical
applications and in close-range applications like architectural
and archaeological photogrammetry. It provides data already in
3D form.
Topology in 3D models is very important issue. Only
topologically consistent 3D models could be used for querrying
the database. The benefit of a 3D model is fully used when it is
possible to view it with one of the stereoscopic techniques. A
mobile construction for displaying stereoscopic 3D virtual un : o
environment, called VR mobile, developed and constructed in We need only the shape of the building and its characteristic
Slovenia, is shortly presented in the paper. height. It is not difficult to assure the topology of such models.
The second level is representing the roofs of buildings with
The approaches of data integration and data visualisation in some predefined typical forms (Figure 2).
Slovenia are presented in the paper, demonstrated on the
example of 3D city model of Ljubljana, the capital of Slovenia.
The project was financed by the Municipality of Ljubljana, that
also provided all the necessary data. The model was generated
by Geodetic Institute of Slovenia. With cooperation of Navidez
[Interactive Systems Ltd. company, a stereoscopic projection of
the model was prepared for the meeting of the municipality
council.
Figure 1. Buildings represented as blocks
Figure 2. Predefined types of roofs
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