International Archives of the Photogrammetry, Remote 
  
2.7 Rendering 
To render the model, we applied the following two methods. 
The first method, which fakes global illumination, is very 
popular in the visual effects industry due to its fast render times. 
The conventional technique to obtain a faked global illumination 
which approximates atmospheric diffusion, is to use a light rig 
of spots with shadow maps. The result is interesting, as there is 
a sensation of light coming from every point of the space and 
the general feeling is that of a gloomy cloudy day. Fig. 3 was 
rendered using this method. 
The second method we used, is a combination of ambient 
occlusion with image-based lighting. The image-based lighting 
was based on the panoramic image of the monuments 
surrounds (shown in figure 10). The ambient occlusion 
approach yields extremely realistic shadow effects for outdoor 
scenes by computing single bounces of indirect light on diffuse 
surfaces. This makes it a perfect match for image-based 
lighting. It adds detail in areas of the scene with many edges 
and sharp light variations (see figs. 11, 12 and 13). 
Fig. 14 shows the same shot rendered with the two methods 
side by side. While the picture on the top took 7 minutes to 
render on a modern PC, the picture on the bottom took more 
than 2 hours. Therefore, the first method has been used for the 
movies that we have produced, whereas the more sophisticated 
second method was only used for some of the stills. 
  
  
Figure 11. Fourth pediment from the left. The image shows 
several of the motifs that are repeated all across the aediculae. 
Close-ups of these are shown in the bottom two images. 
  
   
    
  
  
  
  
   
  
  
    
  
  
  
  
  
  
  
  
   
  
  
  
  
  
  
  
  
   
  
  
  
  
  
  
   
  
   
  
    
    
Sensing and Spatial Information Sciences, Vol XXXV. Part B5. Istanbul 2004 Interna 
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Figure 12. Second pediment from the left. The figure also 
shows some additional ornamental motifs, including the 
Corynthian capitals. Close-ups are shown in the bottom two 
images. 
  
Figure 13. Second niche from thc left