Switchable desktops were designed and implemented at Xerox PARC as "Rooms" by D.A. Henderson and Stuart Card in 1986 based upon work by Patrick P. Chan in 1984. This work was covered by a US patent.
Other kinds of virtual desktop environments do not offer discrete virtual screens, but instead make it possible to pan around a desktop that is larger than the available hardware is capable of displaying. This facility is sometimes referred to as panning, scrolling desktops or viewport. For example, if a graphics card has a maximum resolution that is higher than the monitor's display resolution, the virtual desktop manager may allow windows to be placed "off the edge" of the screen. The user can then scroll to them by moving the mouse pointer to the edge of the display. The visible part of the larger virtual screen is called a viewport.
Virtual desktop managers are available for most graphical user interface operating systems and offer various features, such as placing different wallpapers for each virtual desktop and use of hotkeys or other convenient methods to allow the user to switch amongst the different screens.
The first platform to implement multiple desktop display as a hardware feature was Amiga 1000, released in 1985. The Amiga moved on to succeed in the consumer and video production market. All Amigas supported multiple in-memory screens displayed concurrently via the use of the graphics co-processor, AKA the "Copper". The Copper was a simple processor who could wait for a screen position and write to hardware registers. Using the GUI implemented in system ROM API's, programs could transparently display multiple independent screens, from non-consecutive memory, without moving the memory. This hardware-based scrolling does not use blitting, but something more like what is sometimes called hardware panning. The video output is simply told (once, or many times) where to display (scanline) and from what screen memory address. A screen can move to any position, or display any portion, by modifying the wait, or fetch position. Typically a single byte value. The Copperlist did need to be sorted in vertical and horizontal wait position in order to function. Note: See http://www.faqs.org/faqs/amiga/books/ for a list of reference material.
Each desktop or 'screen' could have its own colour depth (number of available colours) and resolution, including use of interlacing. The display chipset ('graphics card' on a PC) could switch between these desktop modes on the fly, and during the drawing of a single screen, usually with three pixel deep line between each desktop shown on the screen. However, if one interlaced (flickering) desktop was displayed, all desktops onscreen would be similarly affected.
Some programs, VWorlds (an astronomy simulator) being an example, used the multiple desktops feature to overlay a set of controls over the main display screen. The controls could then be dragged up and down in order to show more or less of the main display.
The X Window System is unique in that the decoration, placement, and management of windows are handled by a separate, replaceable program known as a window manager. This separation allowed third-party developers to introduce a host of different window manager features, resulting in the early development of virtual desktop capabilities in X. Many of today's X window managers now include virtual desktop capabilities. Configurations range from as few as two virtual desktops to several hundred. The most popular desktop environments, GNOME and KDE, use multiple virtual desktops (two or four by default). Some window managers, like FVWM, offer separate "desks" that allow the user to organize applications even further. For example, a user may have separate desks labeled "Work" and "Home", with the same programs running on both desks, but fulfilling different functions. Some window managers such as dwm support "tagging" where applications can be configured to always launch on a particular, named desktop, supporting automatic organization and easy navigation. IBM's personal computer OS/2 operating system included multiple desktops (up to 4 natively) in the OS/2 Warp 4 release in 1996.
Other kinds of virtual desktop environments do not offer discrete virtual screens, but instead make it possible to pan around a desktop that is larger than the available hardware is capable of displaying. This facility is sometimes referred to as panning, scrolling desktops or viewport. For example, if a graphics card has a maximum resolution that is higher than the monitor's display resolution, the virtual desktop manager may allow windows to be placed "off the edge" of the screen. The user can then scroll to them by moving the mouse pointer to the edge of the display. The visible part of the larger virtual screen is called a viewport.
Virtual desktop managers are available for most graphical user interface operating systems and offer various features, such as placing different wallpapers for each virtual desktop and use of hotkeys or other convenient methods to allow the user to switch amongst the different screens.
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Some programs, VWorlds (an astronomy simulator) being an example, used the multiple desktops feature to overlay a set of controls over the main display screen. The controls could then be dragged up and down in order to show more or less of the main display.
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