4. PLOTTING 
The 3-D data obtained using this methodology constitute 
a valuable documentation for any future control reference 
or subsequent modifications. Once the plotted image is 
being made, it would in fact be difficult to distinguish those 
features that have been measured from the ones that are 
being the result of subsequent interpretations. It is therefore 
necessary to preserve accurately a file containing the 
justification documents, the field book, the calculations 
and the drafts that would allow an identification of the holes, 
interpolations and secure elements and thereby a later 
control of the validity of information. 
On the other hand, if the acquiring and elaboration systems 
are able to make the 3-D structures it is also true that the 
plotted designs that are currently requested, as a rule 
conventionally orthogonal two-dimensional. Maybe it 
should, therefore, be necessary to return to iconic models 
adequate to the possible designs and to the space-time 
data related thereto. Using currently available commercial 
softwares one thing is memorizing the points in 3-D in 
order to link polylines really in 3-D, and the other one is to 
create a design that would satisfy the descriptive 
requirements to the scales normally used in 
documentation and in projects of conservation. If the link 
between the measured points (that could be so dense to 
create a real and proper topographic DEM) could lead to a 
structural model of the object of the study up to a stage 
where it is possible to appreciate (with certain interest) its 
volumetric features and the shape of the surfaces, in most 
cases the same is included, in the processing office, to 
add to the level of detail required for the final design of the 
architectural measurement as it is commonly known. 
Another problem directly connected to the selection of 
graphical conventions lies in reference system and 
therefore in projection surfaces that is more adequate to 
the graphic representation. In case study, the reference 
system that has been chosen had X axis parallel to the 
facade and Y axis parallel to the longitudinal section, 
determined by the middle line of the initial and final spans 
of the central nave. 
Normally, orthographic projections cancel representation 
of the planes perpendicular to draft but, as a rule, the 
ornaments on the facades of the historical buildings have 
Figure 8. Longitudinal section. Graphic representation is still in progress. 
Figure 9. A vector - raster visualisation of longitudinal section.