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2 Geomatics standards
France in 1976 and the standard was published in 1985. GKS is a generic standard
for 2-dimensional vector graphics independent of operating systems, programming
languages, and output devices. Language bindings for four important programming
languages that followed. GKS has been used in a number of systems and can be considered successful. However, even at the time GKS was published, some of its elements still performed too slowly for larger volumes of mapping data.
During the following years, GKS was extended to include the third dimension.
Differing philosophies on the development ISO resulted in two incompatible new
standards being published. The European solution, ISO 8805 (GKS-3D), was upwardly compatible to ISO 7942 (GKS) while the US-supported solution, ISO 9592
(PHIGS, Programmer's Hierarchical Interactive Graphie System) was an independent development. GKS-3D and PHIGS share a common core of concepts but they
differ in the handling of display lists. GKS-3D supports a linear segment storage
concept while PHIGS supports a hierarchical store.
In order to draw a complete pieture, two other first generation standards must be
mentioned. The ISO 8632 (CGM, Computer Graphics Metafile) and the ISO 9636
(CGI, Computer Graphics Interface). Both of these standards share the same concepts such as primitives and attributes that are currently used in many areas. A direct
use of CGM was output but with the advancement of technology, Postscript, PCL,
and now SVG would be the currently preferred expression language. This would be
the same reason that CGI level interface is now internal to boards.
These standards are no longer used for new developments because some legitimate uses that would commonly be thought of as "Computer Graphics", are not addressed. Amongst these are:
• Image processing applications. The successful processing of images was not
commonplace before the wide availability of raster devices.
• Window management. Graphics standards were developed at a time when the full
physical resources on each display would be available to a single application,
whereas today, window management systems are based on the dynamic partitioning of a set of resources among tasks.
• High quality typesetting. The quality of text facilities available on modem systems far exceed those expected to be widely available in the original timeframe of
the standard's development. Consequently, the text facilities are neither simple
enough for convenient use by a novice, nor sufficiently sophisticated for control
of high quality typesetters (Amold and Duce 1990).
Graphie format standards
The W orking Groups on the computer graphics standards are affiliated to the
ISO/IEC JTC1, the "Joint Technical Committee I" ofISO (International Organization for Standardisation) and IEC (International Electrotechnical Organization). The
ISOIIEC JTCl addresses international Information Technology standardisation that
is on the borderline between the traditional ISO and IEC fields of work. The
ISOIIEC JTCl is subdivided into a number of Subcommittees (SCs) whose work has
2 Geomatics standards
France in 1976 and the standard was published in 1985. GKS is a generic standard
for 2-dimensional vector graphics independent of operating systems, programming
languages, and output devices. Language bindings for four important programming
languages that followed. GKS has been used in a number of systems and can be considered successful. However, even at the time GKS was published, some of its elements still performed too slowly for larger volumes of mapping data.
During the following years, GKS was extended to include the third dimension.
Differing philosophies on the development ISO resulted in two incompatible new
standards being published. The European solution, ISO 8805 (GKS-3D), was upwardly compatible to ISO 7942 (GKS) while the US-supported solution, ISO 9592
(PHIGS, Programmer's Hierarchical Interactive Graphie System) was an independent development. GKS-3D and PHIGS share a common core of concepts but they
differ in the handling of display lists. GKS-3D supports a linear segment storage
concept while PHIGS supports a hierarchical store.
In order to draw a complete pieture, two other first generation standards must be
mentioned. The ISO 8632 (CGM, Computer Graphics Metafile) and the ISO 9636
(CGI, Computer Graphics Interface). Both of these standards share the same concepts such as primitives and attributes that are currently used in many areas. A direct
use of CGM was output but with the advancement of technology, Postscript, PCL,
and now SVG would be the currently preferred expression language. This would be
the same reason that CGI level interface is now internal to boards.
These standards are no longer used for new developments because some legitimate uses that would commonly be thought of as "Computer Graphics", are not addressed. Amongst these are:
• Image processing applications. The successful processing of images was not
commonplace before the wide availability of raster devices.
• Window management. Graphics standards were developed at a time when the full
physical resources on each display would be available to a single application,
whereas today, window management systems are based on the dynamic partitioning of a set of resources among tasks.
• High quality typesetting. The quality of text facilities available on modem systems far exceed those expected to be widely available in the original timeframe of
the standard's development. Consequently, the text facilities are neither simple
enough for convenient use by a novice, nor sufficiently sophisticated for control
of high quality typesetters (Amold and Duce 1990).
Graphie format standards
The W orking Groups on the computer graphics standards are affiliated to the
ISO/IEC JTC1, the "Joint Technical Committee I" ofISO (International Organization for Standardisation) and IEC (International Electrotechnical Organization). The
ISOIIEC JTCl addresses international Information Technology standardisation that
is on the borderline between the traditional ISO and IEC fields of work. The
ISOIIEC JTCl is subdivided into a number of Subcommittees (SCs) whose work has