Workbench (AmigaOS)

Workbench Overview [Classic Amiga]

With the Amiga computer, the name Workbench refers to the native graphical interface file manager and application launcher of the Amiga Operating System typically presented to users upon booting the Amiga. The Workbench was not required to boot the Amiga or run other applications, but was a standalone application listed in the "startup-sequence" script.

The Amiga Workbench used the metaphor of a workbench rather than the now standard desktop for exposing file management and application launching functionallity. The Workbench application appeared similar to other consumer Operating Systems of the era by utilising a trash can, menu bar, and icons to represent files, folder and volumes (filesystem devices). The underlying AmigaOS was much more advanced allowing the Workbench to launch multiple applications that could execute at the same time and communicate with each other. The Amiga used a two button mouse for left click and right menu.

The Amiga did not use file extensions to normally distinguish file types. Instead the Workbench used a separate file of the same name but followed by ".info". That was the only file extension Workbench recognized. This file supplied information such as the icon graphic to display, the application to launch with, etc. Similar in many ways to a Windows ".pif" file. Most files were human recognized by name (32 cased characters) or associated icon, or by applications using embedded metadata. The common format containing open metadata was the Interchange File Format which allowed applications to access the known parts of even a completely foreign IFF format file.

The Workbench utilized the underlying AmigaOS API to provide the GUI interface. Much in the same manner that Windows did prior to the NT Kernel (Windows NT, Windows 95) with MS-DOS. The actual Workbench in its executable format (loadWB) was quite small only taking a fraction of an Amiga 880k 3.5 inch floppy disc or other medium.

The AmigaOS library API's required by WorkBench were stored in ROM, or on the earliest Amigas loaded into WCS/WOM (Lockable/Write Once Memory) by the Kickstart system. Applications launched via either the CLI or Workbench executed equivalently, both having full GUI functionallity. Workbench launched application were meant to report their successful launch back the Workbench but it was not enforced, and few actually did. The CLI was entirely graphically based as they Amiga hardware did not support character mapped displays.

The AmigaOS provided the ability to use multiple draggable Virtual Desktop screens. All gadgets of the Operating System could be used on any screen, and applications often did but Workbench did not utilise that feature. The Desktop screens were not persisent and even now (nearly 25 years later) Operating Systems are struggling to handle multiple desktops effectively. Extending to physical screens would have not affected applications as the screens were entirely managed by the AmigaOS.

Underlying the Workbench is the "Intuition.library" windowing system. This library controlled the logicistics of clipping, rendering and preserving overlapping screens, windows and gadgets. The graphics.library provided the rendering to memory via both software and hardware means. The exec.library handled low level functions such as input from the keyboard and mouse, passing messages to programs, allocating memory and tasking switching.

The Workbench name can also refer to the main OS floppy disk for AmigaOS versions 1.1 to 1.3 (the "Workbench disk"). This was due to an error of Commodore marketing. This fact led some Amiga users to believe that all of the AmigaOS was named "Workbench". Commodore re-introduced proper names for the AmigaOS disks, starting from version 2.0.

Workbench 2.0 user interface improvements

Until AmigaOS 2.0 with its GUI Workbench 2.0, there was no unified look and feel design standard - application developers had to write their own widgets (both buttons and menus) if they want to enhance standard basic widgets, with Intuition providing minimal support. With Workbench 2.0 it was created "gadtools.library", which provided standard widget sets, the "Amiga User Interface Style Guide" [Commodore-Amiga 1991] , which explained how applications should be laid out for consistency. Intuition was improved with BOOPSI (Basic Object Oriented Programming system for Intuition) which enhanced the system with an object oriented interface with a system of classes in which every class individuate a single widget or describes an interface event. It can be used to program Object Oriented interfaces into Amiga at any level.

The BOOPSI system led an evolution in which third parties developers realized each own his personal system of classes. So there were born MUI (Magic User Interface) and ClassAct which then evolved into ReAction. MUI became the standard GUI engine for AROS and MorphOS. ReAction it is now the GUI engine of AmigaOS 4.0. There are also modern interfaces based on XML, like [http://www.feelin.fr/ Feelin] .

Workbench 2.0 also added support for "public screens". Instead of the Workbench screen being the only shareable screen, applications could create their own named screens to share with other applications.

Workbench 2.0 introduced "AmigaGuide", a simple text-only hypertext markup scheme and browser, for providing online help inside applications. It also introduced "Installer", a standard software installation program, driven by a LISP-like scripting language.

Finally, Workbench 2.0 rectified the problem of developers hooking directly into the input-events stream to capture keyboard and mouse movements, often locking up the whole system. Workbench 2.0 provided "Commodities", a standard interface for modifying or scanning input events. This included a standard method for specifying global "hotkey" key-sequences, and a "Commodities Exchange" registry for the user to see what commodities were running.

Workbench 3.0, 3.1

Originally shipped with the A4000 and A1200 AGA machines.

OS3.1 would ship later, adding improvements, and with a new V40 ROM, supported the A2000, A3000, and A500 machines.

Introduced Datatypes. This was a mechanism that allowed any datatype aware application to add new features by simply installing a datatype. The datatype is a library that can be called by an application as needed.

Through this mechanism, Amiga web browsers that supported datatypes were the first to support PNG. The programmer didn't have to concern himself with supporting multiple image formats. By simply employing datatypes, the application could add new image types as the datatype became available.

One application of note was Multiview. Its capabilities were directly related to the datatypes installed in Devs:Datatypes.

Workbench 3.5

Workbench 3.9

This version of Workbench was created in 1998 with AmigaOS 3.9 by German Amiga software manufacturer and reseller Haage&Partner. Copyright date is 2000.

System requirements to install OS3.9 were a 68020 CPU, minimum, with hard drive, CD-ROM drive, and 6 Megs of RAM. Was never made available on floppy disks, only on a CD. Many users complained about the lack of install floppies, and the '020 and CD-ROM requirementFact|date=May 2008.

Workbench 4.0

Along with AmigaOS 4.0 the Workbench 4.0ref num|Workbenh 4.0 image for fair use|1 was entirely rewritten starting from AmigaOS 3.1 by Belgian firm Hyperion VOF.

Since AmigaOS version 4 a new technique is adopted and the screens are draggable in any direction. Drag and drop between different screens is possible too.

Workbench icons

The icons that Workbench uses to represent the files in a volume or a drawer are stored in special .info files, with the name of the .info file matching the name of the file it represents. For example, the icon for NotePad, a text editor, is found in the file NotePad.info.

The .info file includes the graphical representation of the icon and its position in the volume or drawer window. The icon also specifies the type of the file, as used by Workbench. Workbench recognises five different file types [Ryan 1990] :
* Tool: An executable program.
* Project: A data file of an executable program. The program which created the file is named in the icon file, double-clicking on the icon loads the program that created it.
* Drawer: A directory containing files, and other drawers.
* Volume: A physical disk or a RAM disk.
* Garbage: The Trashcan - a deleted file backup, which works in a similar way to the 'Recycle bin' in Microsoft Windows.

An additional three file types are available and are intended for future expansion:
* Device: designed for displaying information about attached devices
* Kick: The icon of a bootable disk
* App Icon: An icon which will be used as (part of) the GUI for an application

Of these three file types, only "App Icons" currently are used by any part of Workbench/AmigaOS.

Tool files can include "tool types" in the .info file. These are used as configuration options for the program. Each tool type is a single line of text, which can optionally include parameters, written after an = sign. Tool types can be commented out by writing them in parentheses. For example, the tooltype "CX_POPKEY=ctrl alt f1" says that the application (a "Commodity") will pop up the user interface in response to the key sequence Ctrl-Alt-F1.

The colours used in the icon are normally only stored as indices to the Amiga Workbench screen's current palette. Because of this, the icons' colour scheme is inherently tied to the chosen hues in the screen's palette, and choosing non-standard colours can give the icons an ugly appearance. This problem was party solved by a third-party system called NewIcons, which adds additional features to the standard .info files. Unlike normal Workbench icons, NewIcons include actual RGB colour information, and the system tries its best to match the icons' colour hues to those in the screen palette.

Since AmigaOS 3.5, Workbench supports icons with up to 256 colors. This release of AmigaOS features the Glowicons icon set by Matt Chaput. With AmigaOS 3.5, a screen-palette-independent system is used. The 4.0 icons, designed by Martin Merz, can use a palette of 32 bit each.

Notes

* AmigaOS 4.0 Image included in this article it is intended for fair use. Neither Hyperion VOF (Belgium), nor Amiga Inc. (USA) never opposed in the past to publishing in internet sites of AmigaOS4.0 screenshot kindly donated by users. Owners of Copyrights are free to register and write in the talk page of this article to ask for the removing of this image from article, and to ask also for its deletion from Wikipedia images.

References

*cite book |last=Commodore-Amiga Inc. |year=1991 |title=Amiga User Interface Style Guide |publisher=Addison-Wesley Longman Publishing Co., Inc. Boston, MA, USA |isbn=0201577577 |ref=Com91
*cite book |last=Ryan |first=Bob |year=1990 |title=Official AmigaDOS 2 Companion |publisher=IDG Books |isbn=1878058096 |ref=Rya90

External links

* [http://www.gregdonner.org/workbench/ The Workbench Nostalgia Page]
* [http://www.amigau.com/c-amiga/replace.htm Amiga University - Amiga Workbench Replacements]
* [http://www.amigahistory.co.uk/amigaos-ng.html All versions of Workbench] explained on AmigaHistory site
* [http://codewiz.org/projects/amiga/ How it works BOOPSI] at Codewiz.org
* [http://www.flux.utah.edu/~stack/introduction.html functioning of BOOPSI] at The Flux Research Group, University of Utah.