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International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B4. Istanbul 2004 
Navigation was enhanced reducing by a factor of 4 the re- 
quired time to explore it. 
    
  
Figure 3: Original VRML object (left) and its LOD (right). 
    
  
Figure 4: Original, blurred and sampled images. 
  
Figure 5: Example of symbolization operator. 
The figure 6 exibits this historical quarter and the figure 7 
exibits the result of generalization process in this virtual 
world. 
S CONCLUSIONS AND FUTURE WORKS 
This work presented a transposition of ideas and tools from 
the realm of Cartographic Generalization to the managing 
of virtual reality worlds. A system for implementing this 
transposition was developed, and it is successful in per- 
forming its task. More operators are under development 
for extending the functionality of the system. 
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203 
  
     
ET demere 
Figure 6: Historical quarter of the city of Recife 
  
Figure 7: Result of generalization process in the historical 
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