GIS applications
|
GIS server
Communcation
services
Figure 1: Client-server architecture for future GIS systems.
agement, analyses, modelling and output. Object-
oriented organization, client-server architecture and
effective development environments enable developers
to supply GIS applications (clients) in optimal struc-
ture and extent. These applications will have user
interface tuned for particular study field, technologies
and data.
Correct data exchange and communication with other
systems (such as office software) is also necessary. For
this reason open data and communication standard
are created. The development of GIS system architec-
ture standard is currently done within the Open GIS
project. Common standards for data exchange and
program communications are developed in computer
industry. The most important project seems to be ef-
fort of the Object Management Group in the project
for access to object data and services within Common
Object Request Broker Architecture (CORBA) frame-
work. First experimental implementations of this ar-
chitecture was created and new revisions of this stan-
dard are improved with help of experience from the
existing prototypes.
3 Object-oriented data organization
Data are the most critical and important part of GIS
technology. Systems based on traditional topologic
and topographic data organization are considered to
be “real GIS” systems. But classical data organiza-
tion centered around geometrical objects imposes sev-
eral limitations on data organization. Such a system
should be labelled like Gis systems as their are con-
centrated on geometrical and geographical view at the
expense of information and descriptive part.
Future data organization will shift from traditional
view based on geometrical objects (points, lines and
areas) and layers to user-oriented view based on the-
matic objects and geographical blocks. Thematic ob-
jects encapsulate a complete entity, which contains
information attributes, executable methods as well as
set of spatially referenced geometrical elements in both
vector and raster form. Encapsulated pictures, sound
and video clips introduce new media to form sophisti-
cated multimedia GIS systems. These objects provide
users with access to essential information to complete
their tasks and achieve necessary results.
460
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B3. Vienna 1996
This information era creates unlimited amount of in-
formation data and future developments should cre-
ate tools for management and access of these data.
Spatial catalogues and hypermaps might be solutions
for future organization of georeferenced data. Future
GIS servers will provide tools for registration of data
in spatial catalogues. This catalogues provide users
with easier access to large data sources based on their
spatiallocations. Efficient data query tools should be
developed for simplification of data access. Notion of
hypermaps with links between objects, blocks and cat-
alogues creates structured framework for data access.
Data exchange within large network environments
should be also facilitated with GIS data definition lan-
guage and format description. These tools should en-
sure data compatibility for future data access and pro-
vide easy way for extension adoption during the future
developments. Canadian standard SAIF is the first
attempt to create object-oriented data standard with
data description language. This standard has also in-
fluenced developments within Open GIS project.
Data organization described above require modern
computer technologies for data store and access. The
development of modern object-oriented database sys-
tems enable GIS developers to store GIS data with
object organization in natural way. This database sys-
tems should be amended with spatial indexing mech-
anism for data spatial sorting. There are also efforts
for specification of common spatial query languages,
which provide tool for quick georeferenced data ac-
cess and analyses of positional relations within GIS
systems.
Sophisticated data organization and computer tech-
nologies should enable developers to create generic
Geographical Information Management Sys-
tems (GIMS) which will form future generation of
GIS systems. Object-oriented extensible data orga-
nization and open development environment for the
creation of GIS applications based on client-server ar-
chitecture provide the required base for the effective
development of user-oriented GIS applications.
4 Sophisticated multimedia systems
From the point of view of computer technologies the
last decade of this century can be considered like
era ol
all co
use r
and €
and c
adopt
probl
gies i
Futur
tion €
well :
appli
not b
conce
It is
videc
data.
ural
enab.
sic, a
ner.
tial d
ing. .
struc
of us
nizat
