International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B2. Istanbul 2004 | Interna
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2001) for 3D visualization. The study area was Hong Kong's
| Foley, .
East Lamma Channel. | Comput.
Our own work, based on the ongoing development of Addiso
GeoScene, was to take the virtual world manipulation tools
already developed, and add those features that are specific to Ford, S
marine navigation, and in particular those features identified in Dawn
the IHO S57 standards. Press, 2
So, on top of GeoScene, a general *S57Object" class was | Gold, (
created, and sub-classes were created for each defined S57
object. These included navigational buoys, navigational lights,
Marine
soundings, depth contours, anchorage areas, pilot boarding Gold, €
stations, radio call-in points, mooring buoys, traffic separation integrat
scheme lanes, traffic scheme boundaries, traffic separation Marine
lines, precautionary areas, fairways, restricted areas, wrecks,
and underwater rocks. See the following figures for examples. Iu 7017 PROPERTIES. | Gold, (
Other objects include ship models, sea area labels, 3DS models, 2 La Ph 5 encima Puce | adjacen
range rings and bearing lines, and oil spill trajectory simulation S EET ede | Geogra
results. Various query functions were implemented, allowing : Buoy Color: black, yellow. block. | Taylor :
for example the tabulation of all buoys in an area or the ea stop |
selection of a particular buoy to determine its details. Selecting ve = | Gold, €
"Focus" for any buoy in the table moves the window viewpoint Imo = | Vorono
to that buoy. Safety contours may be displayed along the 9. : UE, |
fairways (Fig. 4), and a 3D curtain display emphasizes the safe Meme IOS bbüuybshgquesó 7 | Gold, C
channel. Fog and night settings may be specified, to indicate the iis SCENES | mappin,
visibility of various lights and buoys under those conditions. Figure 7: Lists of Navigational Buoys
Safety contours and control markers may appear illuminated if a | Gold, C
desired, to aid in the navigation. The overall result is a | Wright,
functional 3D chart capable of giving a realistic view of the Geogra,
navigation hazards and regulations. For example, Fig. 5 uses 3D
labels for sea area identification, Fig. 6 shows details of
Francis.
navigation buoys and lights, Fig. 7 shows the results of | Guibas,
querying a particular buoy in the 3D display, and Fig. 8 shows of gen
the result of adding oil-spill simulation. diagram
?18.322 N 11492,7272 E. | Brakes ri Dee frise ee per E P ; Hill, B.
. : m : x | Jersey: |
Figure 8: Visualization of Oil Trajectory Record |
Internat
8. CONCLLSIONS Standar
Publica
In this paper we have outlined the difficulties in developing a
real “Marine GIS”, and our attempts to respond to the problems. Internat
We believe that a combination of modern interactive | THO for
visualization tools and the appropriate kinetic spatial data | THO.
structures is a significant step in the right direction. |
Li R à
Figure 4: Visualization of Safety contour with vertical 9. ACKNOWLEDGEMENTS | marine
extension pp. 293-
The first author would like to acknowledge the Research Grants
Council, Hong Kong, project PolyU 5068/00E for the support Lockwo
of this research. informa
| 18:157-
10. REFERENCES
| Oostero
Aurenhammer, F., 1991, Voronoi diagrams - a survey of a | Topolog
fundamental geometric data structure. ACM Computing | Databas
Surveys, 23, pp. 345-405. | 1997, py
Blinn, J.F, 1977. A homogeneous formulation for lines in 3- Rohlf,
space. Computer Graphics v.11 no. 2, pp.237-241. perform
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Figure 5: Visualization of Sea Area Label Using 3D fonts Davis, B.E. and Davis, P.E., 1988, Marine GIS: Concepts and |
considerations. Proceedings, GIS/LIS'88, San Antonoi, TX, |
USA, pp. 159-168.
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