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includes the mansion known as the house of Harlequin, the 
famous mask from the city of Venice. 
The village, dated 15th century, still presents signs of the 
ancient architecture characterising the foreign-trade stations of 
the republic of Venice. Some meaningful buildings of this 
settlement have been surveyed for purpose of documentation 
and preservation, using techniques of digital imaging 
(Colombo, 1999). 
The collected vectorial and raster information has been 
processed inside the 3DStudio modeller in order to generate a 
virtual photo-realistic reconstruction; this was performed 
according to the tolerance values of a predefined level of 
accuracy. 
The documentation of details (roofs, etc.), the geometry of 
which cannot be reconstructed by photogrammetry, is realised 
with the support of surveying measurements and graphical-data: 
this way the collected morphology is described by "synthetic 
textures" rather than by "photo-textures". 
So, the whole object is represented, but it's possible to 
recognise at first sight all the zones acquired by different 
precision techniques. 
2D bitmaps and/or 3D models, produced by photo-textured 
rendering, provide a "datum" for georeferencing historical, 
architectural and thematical hypertexts inside Internet or in 
Intranet databases. 
The performed procedures were supported by well-known 
packages, such as AutoCAD (graphics), 3DStudio (modelling, 
rendering, texturing), Photoshop (image processing), Siscam 
Archis and New Orthomap (imaging). 
The mean photo-scale was set to 1:200; so the image processing 
has involved pixels (colour RGB) sized to 25 pm (scanning 
resolution at 1000 dpi), according to technical standards for 
1:50 plotting scale. 
The orthogonalisation of bitmap data for the building façades 
(fig. 2, on previous page) has been realised by mosaicking 
rectifications and/or ortophotos. These raster products were 
then projected over the models of surfaces (DSM), the density 
of which fitted the morphology of the walls. Applying these 
imaging techniques, a photo-realistic model of the village has 
been reconstructed. 
It remarks, in a suggestive way, the great effectiveness of a 3D 
bitmap description versus a traditional 2D vectorial 
representation (Gruber et al., 1997). 
The Harlequin site, as already said, has been realised by 
FrontPage "Editor" and "Explorer" programs. The images 
included in HTML documents are suitable for a visualisation on 
PCs with standard graphical cards (resolution equal to 800 by 
600 pixels). 
Figure 3 (on previous page), performed in Netscape, supplies 
the thematic map for an interactive visit inside the village. 
The final structure of the site, with folders and files, is 
described in figure 4 (on previous page). 
Front Page provides tools for managing links to 3D VRML 
models: these connections allow the user to move throughout 
three-dimensional worlds and to live therefore suggestive 
experiences and feelings inside virtual reality. 
Figure 5 (on next page) shows in Netscape the global model of 
the village, visualised with the support of the Cosmo Player 
plug-in: the visitor of the site has at his disposal also this 3D 
tool to make analyses and inspections. 
4. FINAL REMARKS 
The introduction of realistic models is getting an important 
improvement to documentation, qualitative perception and 
space analysis of objects. 
It is well known the importance of spatial metric knowledge for 
historical heritage, till now requested unfortunately in few 
cases. Now, geomatic techniques can simplify the process of 
survey. For instance, it's possible to reduce the use of 
stereoscopic observation; besides, vectorial plotting can be 
produced sometimes via software in a nearly automatic way. 
This can be achieved performing edge detection over pre- 
orthogonalised raster images (the package Cad Overlay by 
Autodesk is suitable for these requirements). 
It seems to lead to the development of "expert systems" also in 
the field of survey and representation. 
The new "distributed" photogrammetry directly involves the 
end-user (historian, archaeologist, architect etc.) in the process 
of documentation. 
These changes should be cost-effective, make the geometric and 
thematic analysis easier and faster, improve the level of 
documentation and supply a photo-realistic three-dimensional 
model with metric reliability. 
Therefore, it will be possible to offer a more significant 
knowledge of Cultural Heritage and guarantee its witness. 
Moreover, historical buildings with a high "risk assessment" 
will become visible also in a virtual way, creating a 
"complementary" museology able to protect them without 
subtracting their availability to every citizen. 
5. REFERENCES 
Colombo L. (1999): Photogrammetric imaging for virtual 
reality: an example of settlement documentation. International 
Archives of ISPRS, n. 32 - part 6w2,WG VI/3. 
Colombo L., Marana B. (1999): Geomatics for Cultural 
Heritage web sites. GIM International, n.3. 
Gruber M., Pasko M., Leberl F. (1997): Geometric versus 
texture detail in 3D models of real world buildings. Cism, 
Udine, Italy. 
Hoffman P. (1998): Netscape Communicator 4. Apogeo, Milan. 
Karlins D. (1998): FrontPage 98. Apogeo, Milan. 
Peterson M. T. (1998): 3D Studio MAX 2. Apogeo, Milan. 
Tittel A., Scott C., Wolfe P., Sanders C. (1997): VRML 2. Me 
Graw Hill, Milan.