Graphics Environment Manager

from Wikipedia, the free encyclopedia
GEM version from 1984
GEM 3.1 Desktop (1989)
OpenGEM desktop (2004)

The Graphics Environment Manager ( GEM ) was a graphical user interface from Digital Research , which was best known for the Atari ST computer under the TOS operating system . There were also versions for the IBM PC ( and compatible ) as well as a Unix version. On the Atari computers ST series the TOS also consisted of also of Digital Research developed GEMDOS that strongly on the existing operating system CP / M and PC DOS / MS-DOS -based.

Apple's copyright lawsuit

Shortly after the PC version GEM / 1 appeared in 1985, Apple Computer Inc. sued Digital Research because the look and feel largely corresponded to that of the Macintosh environment (later Mac OS ). The GEM file manager “Desktop” was very similar to the Apple application “ Finder ”. In order to avoid lengthy court proceedings, Digital Research undertook to significantly change the PC version of GEM. In particular, the overlapping windows and the recycle bin have been removed from the “Desktop” file manager. The Atari version was not affected by the restrictions, as its development was the responsibility of Atari itself, which was not legally prosecuted by Apple.

The ruling that there was a copyright on user interfaces led to a temporary boycott of Apple by the Free Software Foundation . The Windows version 1.0 user interface , which is in direct competition with PC-GEM , was published at the end of 1985 and finally gained in importance after Microsoft was sued by Apple for the same reason after the appearance of Windows 2.03 and, unlike Digital Research, the long-standing proceedings in Purchases took until they finally won against Apple in 1992 . So Windows could be further developed without conditions.

Internal structure

The GEM surface usually consists of the following components:

  • The Virtual Device Interface (VDI) provides device-independent drawing functions (comparable to Microsoft's GDI ). It is divided into the following sub-components:
    • Drivers for screen, printer, metafiles, etc. (device-dependent)
    • device-independent layer (GDOS)
  • Building on this, the Application Environment Services (AES) provide routines for displaying various operating elements (menus, windows, dialogs, etc.), as well as for program management, accessories, etc.
  • The desktop is the file manager and program launcher that looks like a desk work surface. Desktop 2.x only has two fixed-size windows due to the dispute with Apple, but it is possible to use Desktop 1.x with GEM 2.x.


GEM Draw Plus 2.0.1 (1988)

Digital Research mainly supplied visually oriented software for GEM. These included the word processor “GEM Write”, the vector program “GEM Draw”, the pixel program “GEM Paint”, the bar graph application “GEM Graph”, the presentation software forerunner “Wordchart”.

The word processor “ 1st Word Plus ” later became one of the most popular programs.

The programming language and graphic development environment Locomotive BASIC  2 was supplied with the Schneider PC1512 , which made it possible in 1986 to create simple programs with windows, graphics, mouse support and the like. a. to write.

PC version

After Caldera took over Digital Research , the PC version was placed under the GPL . Some enthusiasts then reversed the restrictions (e.g. they let the desktop program 1.x run under GEM 2.x) and collected old applications, so that PC-GEM today again has a reasonably usable user interface for simple, less powerful PCs represents. The usable RAM is still limited to 1 MiB. The development of the PC version of GEM will be continued under the name OpenGEM and FreeGEM .

Under the name ViewMAX , Digital Research integrated a function-reduced version of GEM in DR DOS 5.0 - at around the same time Microsoft delivered its counterpart DOS Shell with MS-DOS.

Atari version

The Atari version of GEM has not been further developed since the disappearance of the Atari company as a manufacturer of computers and is also not free software . Instead, the TOS operating system , including GEM, has been reimplemented as free software components (see also: MiNT , fVDI , XaAES , TeraDesk ). Commercial projects were also created (see also: MagiC or Mag! X , N.AES ). In some cases, even completely replace the TOS and only need it to start up (" boot "). The release of the PC version of GEM under the GPL also made it possible to implement the operating system replacement EmuTOS , which was initially intended for emulators, but now also supports original hardware up to the Atari TT , a free GEM, which is the ATARI Version of GEM is becoming more and more similar in terms of function and appearance.

With these new projects, it now also offers multitasking functionality. The change between the individual programs running at the same time can be done, similar to the “classic” Mac OS from Apple (i.e. up to and including Mac OS 9), via entries in the menu bar .

Web links

Individual evidence

  1. The New York Times : Digital Research To Modify GEM , October 1, 1985, accessed December 6, 2015