Figure 6. Stereo observing of the 3D city model in a council 
meeting 
In the 3D model of Ljubljana, proposals of environmental plans 
in some city areas were entered, that enable the citizens of the 
city to discuss on the proposals (Figure 7, new buildings in 
white). 
  
  
Figure 8. Projected cadastral parcels in the model (BreZice) 
Figure 9. Projected city map in the model (Brezice) 
Land cadastral data (shapes of parcels, parcel numbers, etc.) 
could be integrated in the model as well as any other spatial 
data (Figures 8 and 9). 
3.2 Vitrual Reality Modelling Language 
An application was developed for the Municipality of Ljubljana 
that generates a model in the Virtual Reality Modelling 
Language (VRML) of the desired area. It enables interactive 
view on the model in VRML format in Internet browsers (e.g. 
Cosmo Player). 
  
Figure 10. Model in VRML format for observing in browser 
At its core, VRML is simply a 3D interchange format. It defines 
most of the commonly used semantics found in today's 3D 
applications such as hierarchical transformations, light sources, 
viewpoints, geometry, animation, fog, material properties, and 
texture mapping. VRML also serves as a simple, multi-platform 
language for publishing 3D Web pages. This is motivated by 
the fact that some information is best experienced three 
dimensionally, like architecture. Typically these types of 
projects require intensive interaction, animation, and user 
participation and exploration beyond what is capable with a 
page-, text-, or image-based format (i.e., HTML). VRML was 
designed to fit into the existing infrastructure of the Internet and 
the WWW. It uses existing standards wherever possible, even if 
those 
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