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Title
The 3rd ISPRS Workshop on Dynamic and Multi-Dimensional GIS & the 10th Annual Conference of CPGIS on Geoinformatics
Author
Chen, Jun

ISPRS, Vol.34, Part 2W2, “Dynamic and Multi-Dimensional GIS", Bangkok, May 23-25, 2001
224
APPLICATION OF VRML IN A DYNAMIC AND MULTI-DIMENSIONAL DIGITAL HARBOR
Mingyang PAN 1 Yifan LI 2 Depeng ZHAO 3
1 Nautical Science and Technology Institute of Dalian Maritime University, Dalian, China, 116026
Tel: 86-411-4729297 E-mail: panmyfei@263.net
2 ,3 Nautical Science and Technology Institute of Dalian Maritime University, Dalian, China, 116026
Tel: 86-411-4729297
Keywords: VRML, Digital Harbor, WebGIS
ABSTRACT
Virtual Reality Modeling Language (VRML) can create various animated and colorful three-dimensional virtual models on the Internet.
The application of VRML in geographic information systems (GIS) provides earth scientists with a new and interactive way to model
real-life phenomena of the geographic world. In this paper, VRML and WebGIS (geographic information systems based on web)
technology were combined to create a dynamic and multi-dimensional digital harbor system on the Internet. The digital harbor displayed
on browser and can be observed dynamically under any positions, any viewpoints and any zooms. Also, any geographic object in the
digital harbor can be queried for attribute information by clicking it at the three-dimensional virtual scene or triggering directly at a query
page.
1. INTRODUCTION
based on attribute are also available.
The emergence and development of virtual reality technology
provide earth scientists with a new and interactive way to
analyze and model real-life phenomena of the geographic world.
A technology combine virtual reality with GIS is developing
rapidly.
VRML is the most popular technology of virtual reality. It is a
standard file format describing interactive multi-dimensional
multimedia based Internet. VRML can create dynamic and
colorful virtual world, which can contain sound and video, and
whose objects can be animated and accessed interactively by
user. A VRML file can contain other files through hyperlink, a
series of VRML files with hierarchy relationship can create a
limitless dynamic virtual world. The access method of VRML
world is client/server based, VRML file and it’s supporting
resource (such as image, video, sound etc.) are supplied by
server, through internet the desired VRML files are downloaded
to client and interpreted by local VRML-browser (Cosmo Player
of SGI, Community Place of Sony, etc.) into virtual scene which
can be browsed interactively.
The rapid development of GIS and World Wide Web calls for the
emerging of WebGIS. Spatial data in WebGIS site can be
scanned with browser on the Internet, spatial query and spatial
analysis are also available.
2. THE ARCHITECTURE OF DIGITAL HARBOR SYSTEM
In the digital harbor system, a three-tiers architecture of
data-sever/apply-sever/client that often used in WebGIS is
adopted (Fig1).
Web Client Web Server Data Source
Figurel .The architecture of Digital Harbor system
The apply-server in which IIS is running act as a web-sever, and
contain all three-dimensional spatial data stored in VRML files
and texture images of JPGP or TIF format. In apply-server a n
attribute query programme exploited by ASP is running for
accessing the attribute information database through ADO
object.
In Data-server, SQL Server is installed to manage the attributes
information database. The attribute information of all geo-object
is saved in database as records. A unique ID number is used for
linking geo-object in VRML world with its attribute information
record in Data-server.
Ground on the internet-based common character of WebGIS and
VRML, we try to integrate VRML with WebGIS technology to
design and create a Dalian digital harbor system on the Internet.
The architecture of WebGIS is adopted in the system;
three-dimensional spatial data are stored in VRML format file;
and the attribute information is saved in a relational database.
The digital harbor displayed on browser as three-dimensional
scene and can be roamed and observed dynamically,
bidirectional information query based on spatial feature and
In web client, using Netscape or IE with VRML browser plug-in,
user can browse spatial data in three-dimensional virtual scenes
and perform bidirectional information query.
3. IMPLEMENT THE DIGITAL HARBOR SYSTEM
3.1 VISUALIZATION OF SPATIAL DATA
The vector spatial information of Digital Elevation Model (DEM)
of Dalian port area was extracted from an aerial stereograph by