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DigiCULT
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3
D ArchGIS can be used for presenting
all this mapped information or as a
simple 3D viewer for displaying the 3D
scanned artefacts on the Internet.The user
can see the object from any angle, zoom in
and out, and browse its surface for data.
Furthermore, it is possible to visualise the
object at spectrum bands invisible to the
human eye, or even to observe the chemi-
cal elements distribution as mapped on the
surface of the object (Figure 7).
Furthermore, a point from a region of
interest can be selected in order to grant
access to the entire
m
-XRF analysis for
that point which includes chemical com-
position data followed by the respective
spectrograms (Figure 8).
T
he system has the capability to block
unauthorised users from inputting
new data sets into the database; however,
browsing and querying the database is a
free access service with restrictions on the
results. Querying is implemented through
try and texture data (also known as 3 to 4
dimensions of data) in a Web compatible
format like the Virtual Reality Modelling
Language (VRML). However, the
Institute's infrastructure makes possible the
extraction of information from an artefact
that goes beyond the typical 3 to 4 dimen-
sions 3D ArchGIS can be considered as
an enhanced 3D model viewer with
unique features.The system allows data
mapping on the surface of the 3D model
and at the same time composes a unique
tool for browsing and retrieving these data.
The information used for 3D mapping is
grouped according to its physicochemical
attributes, retrieved using the micro X-Ray
Fluorescence (
m
-XRF) technique against
the object's surface to extract the chemical
decomposition (see Figure 3).
T
he initial study involves the digital
acquisition of geometry and texture
from the actual artefact.Then it is parsed
to the 3D ArchGIS to map the data
retrieved from the
m
-XRF system.The
mapping of the data is performed manually
at present (Figure 4). A region of interest is
selected (Figure 5) on the surface of the
3D object that corresponds to the real
object point where the measurements have
been taken.The contribution of 3D
ArchGIS to this task is that it enables study
of the 3D model of the artefact and users
can easily pick the 3D coordinates of the
sampled point just by clicking on the sur-
face of the 3D model (Figure 6).
alise not only the physicality of an object,
but also how it is described in the physico-
chemical database (for example, the surface
distribution of iron in the pigments of the
decoration).This led to the name `3D
ArchGIS' Cultural Database.
FEATURES OF 3D ARCHGIS
3
D ArchGIS is an application based on
the client-server architecture.The
client component has been implemented
as a plug-in for Microsoft Internet
Explorer (see Figure 1).Web browsers are
one of the most widely used and well-
established platforms for presenting multi-
media content while supporting numerous
data formats, from simple text and images
up to live streaming video and 3D graph-
ics. Such a sophisticated client-side soft-
ware component requires an equally
powerful server that will be able to handle
the complexity and size of the data.
Modern multimedia databases can handle
huge amounts of data in a very efficient
manner.Thus,Web browsers are considered
among the programming community as an
ideal platform for the development of
database oriented applications in situations
where the main scope of the system is the
global distribution of multimedia informa-
tion.The current system of archaeological
artefact archiving presents historical infor-
mation in textual format accompanied by
typological data alongside a realistic 3D
representation of the artefact on the same
Web page. A typical 3D scanning system
(see Figure 2) is limited to export geome-
3D
Arc
hGIS
,
2003
3D
Arc
hGIS
,
2003
3D
Arc
hGIS
,
2003
3D
Arc
hGIS
,
2003
Figure 4. Entering data
Figure 5. A new point selected
Figure 6. Registered points
Figure 7. Colour mapping based on data