ınbul 2004 
APPLICATIONS OF 3D CITY MODELS BASED SPATIAL ANALYSIS TO URBAN 
DESIGN 
Zhang Xia" ^ Zhu Qing^ 
* School of Urban Studies, Wuhan University, P.R.Chinal29 Luoyu Road, 430079 Wuhan Hubei, P.R.China- 
tllzx@sohu.com 
° State Key Lab of Information Engineering in Surveying Mapping and Remote Sensing, LIESMARS of Wuhan 
University , P.R.China-zhuq66@263.net 
ISPRS WG 11/6 
KEY WORDS: Spatial Analysis, 3D City Models, Urban Design, Application 
ABSTRACT: 
Urban design is a subject that is concerned with the shape, the surface and its physical arrangement of all kinds of urban elements. 
Although urban design is a practice process needs much detailed and multi-dimensional description, however the urban designer can 
only analyse urban space with script and imagination in the past, and only the urban design guideline and some drawing picture were 
carried out in the traditional design schema. How to improve the quality of urban space effectually and to express the design schema 
perfectly are the problems troubling the urban designer for a long time. The 3D city models based spatial analysis gives the 
possibility of solving these problems. Comparing with the traditional applications of 2D GIS in urban plan, the 3D city models based 
3D spatial analysis would be more meaningful for the urban designer. The computable analysis models could be constructed under 
the urban design guideline. Through the integration of analytical models and realistic visualization models, the 3D spatial analysis 
that is impossible to the 2D GIS can be carried out. 
Instead to be described with some adjective words, the designing schema and rules can be presented and analyzed in 3D virtual 
environment. The change of the urban fabric and the building density could be analyzed through the structure analysis. The noise 
environment, sunshine condition, heat environment, ventilation condition, and pollution condition could be analyzed through the 
physical quality analysis. The control of the height, the color and the style of the buildings, and the evaluations of the surrounding 
environment of the squares and the streets are also available based on the visual impact analysis. The analysis of the distribution of 
different function parts and its proper place are possible through function analysis of urban space. 
Based on the 3D city models, urban designer can express the design concept clearly. With the analysis functions, it is also possible to 
control and improve the quality of urban space effectually. There would be a great progress when we design the urban space with an 
operational 3D analytical system, like Cyber City GIS. 
1. INTRODUCTION forward some new viewpoint for 3D city models based visual 
analysis. 
“The visualization is perhaps the most significant of all In this paper, 3DCM is the spatial framework data body of 
activities in the design process to have been affected by the Cyber City GIS (Zhu Q, Li D R, Zhang Y T, Hong D, 2002), 
development of digital technologies" (Batty M, 2000). How far and it is different from the 3D CAD models. 3DCM is not 
can we go forwards on the way of the application in urban simply as an abstraction of various objects of cities. Besides the 
design? Whether just as a visualization means, or as a decision geometric characters, It also contain the geographic information 
support tool, a kind of ideation platform? It is the problem that and other attributes, for example, the location coordinate, the 
we have discussed for a long time. There is an agreement building height, color, texture and so on. Although the primal 
accepted by most of researcher that the computerized design intention of most 3DCM is for visualization, what we want to 
generation is difficult because of the complex, the originality ^ do now is to go for on the way of its more valuable applications. 
and the to-and-fro process of design. So most of the research 
efforts are concentrate on the space analysis and the decision 2. THE IMPORTANCE OF THE 3D SPATIAL 
Support. ANALYSIS FOR URBAN DESIGN 
In this paper, urban space study based on the 3D city models 
(3DCM) is a kind of special application research. Urban design 2.1 The Present Development of Urban Design 
plays double roles in urban construct process: control and guide. 
To Control and evaluate the form process of urban space 
efficiently is the primary task of urban designer. The 3DCM is 
no doubt a powerful tool because of its characters for multi- 
dimension, visual, and multi-attribute. The objectives of this 
paper are three-fold: (1) provide an introduction to the meaning 
of 3D city models application; (2) set up a research framework 
for the content of application, give the answer for what we 
could do at all using the 3DCM in urban design field; (3) put 
Urban design is the holistic ideation and the arrangement for the 
urban form and the urban environment, and it run through the 
whole process of the urban planning. It is a subject mainly 
involving the shape and the surfaces of all kinds of urban 
elements, and its research focuses on the urban space formed by 
these elements. It has been defined by Barnett (1982) as "... the 
process of giving physical design direction to urban growth, 
conservation and change". In fact, there is not a universal 
definition for urban design, but we can see that the 
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