n with ITABC of 
project aims at the 
f the monumental 
rritory by means of 
and archaeological 
edition led by W. 
ht as a field director 
Khor Rori. At the 
re than half of the 
n brought to light. 
ent of the site had 
ation of the wall 
irried out: October- 
pedition (October- 
)1) researches were 
s of the city (Figure 
lex and the palace- 
s and interesting 
ble and recurrent 
orth-western corner 
ortant section of the 
ouses, a big square, 
of a monumental 
) 
  
  
ied out recently 
[URE OF 
JATA 
ta requires different 
erent approaches to 
otogrammetry, 3D 
reconstruction was 
by archaeologists 
ipped with a total 
1 acquisition such as 
alysis of Khor Rori 
al survey, since the 
jue to erosion and 
in the data in such 
conditions with traditional topographical methods a total station 
reflector-less has been used. 
Once we have obtained real data, some interpolation techniques 
are employed to build a model. So we have reconstructed the 
urban structure and the defensive system of the monumental 
gate that led into the city fitting the empirical data. 
In order to solve the realism vs. reality paradox, we need that 
the model is a representation of real data. In this case there is 
the problem of data acquisition, because the more reliable the 
data, the more useful is the resulting model. 
We have had several objectives by focusing: speed, texture 
mapping, interaction in the system, user interface and data 
visualization. 
3. 3D MODEL RECONSTRUCTION 
Virtual reality is a technology that offers promising perspectives 
for archaeologists. New insights can be gained by immersion in 
ancient worlds, unaccesible sites can be made available to a 
global public. One of the main problems for this aim is the 
generation of the virtual worlds. 
We have also addressed the integration of different kind of data 
(vector and raster) and the use of such a hybrid 3D model for 
the purpose of visualization. We have obtained an integrated 
model that combine both landscape and man-made objects: the 
first is a Digital Elevation Model (DEM) generated by means 
different approach depending of the distribution of the acquired 
data; the second is a truly Digital Surface Model by CAD 
(Gruen, Wang, 2002). When fitting a surface model the data 
point do not have a regular distribution (Figures 6, 7) it is 
necessary to prepare a regular grid for the following TIN 
interpolation. The 3D model results with a smooth structures 
and more precisely in the particular. 
  
  
  
  
Figure 6. The irregular distribution of original data 
  
Figure 7. The primary irregular TIN generated 
In this case the original data have been used to generate the 
primary DEM. It has been converted into a regular 1 meter grid 
raster with 213 x 260 points using a Kriging interpolation in the 
software Surfer (Figures 8, 9). Successively we applied a TIN 
structure only at the regular data of the area interested by 
Points2Polys software (Figures 10, 11). The man-made 
structures are extracted by the topographical survey and the 
structures have been modelled (DSM) and shaded in Autocad 
(Figure 12). For a realistic walk-throughs around the site or for 
looking at specific monuments it is necessary to integrate more 
details into the model. An interesting possibility is given by the 
combination of some different type of models: DEM and DSM. 
The integration is done by integrating CAD DSM model on the 
DEM generated by splines interpolation. The reconstruction of 
every building block ruin separately offers a different level of 
detail: from the territorial morphology to the urban area of the 
city. The whole reconstruction of the site manually with a CAD 
or 3D modelling system required a lot of work. Moreover it has 
been difficult to model complex shapes and to take all the 
details into account (Sakamoto, Chikatsu, 2002). Obtaining 
realistic surface texture is also a critical issue (Miyatsuka, Uno, 
Sakamoto, 2002). In fact the result walls has been approximated 
by planar surfaces, stones all get the same texture, small details 
are left out, etc... 
The texture mapping of the walls and the terrain has been 
processed directly combining the materials from the rectified 
images (Figures 13, 14). 
  
  
  
  
  
T 
150 
Figure 9. The contour-map representation 
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