A Few Definitions
The term "Single Logical Screen" generally referrs to an xscreen that requires more than one monitor to view. It is also sometimes referred to as a "stretched desktop". In the Summit Series, it is often referred to as "SLS". However, because the Accelerated-X Wall Display HX Series allows multiple SLSs to exist in a single display, some confusion can arise about how to use the term.
First, let's understand some "X" terms that will be encountered when discussing X Window System graphics.
The term "display" in the X Window System vernacular means the total display that is created by a single X server; one X server, one display. The display may require many monitors and "views" to show the full display. A view is generally what a monitor can show.
The term "xscreen" is a vewable area of a display that has its own bundaries - a rectangular region defined by its pixel coordinates within a display. It may take more than one monitor view to show a particular xscreen. That is, two monitors side-by-side, for example, could each show one half of an xscreen. In this example, we say that the xscreen is "stretched" across two monitor views. This is the simplest form of a "Single Logical Screen" or SLS.
Configuring SLS Systems
One of the squawks against the Xorg X servers is the difficulty of configuring complex systems. With a dozen or so monitors, some serving as members of an SLS, and others having their own xscreens, the task of configurations is not simple.
Probably the most important benefit of an SLS configurtion with multiple monitors is that a graphical window can be dragged across the multiple multiple monitors that comprise the one logical screen in which they are located. Otherwise, without the one display stretched across the monitors - but rather each monitor having its own xscreen - a window cannot be dragged across a monitor's xscreen boundaries
With a single GPU that can drive two or more monitors, it is possible to configure SLS on two or four monitors (in the case of a Matrox QID Pro, for example, which is a quad-head card) with the MultiView Feature.
However, when it is desired to stretch that desktop across monitors that are driven by more than one graphics chip, things get a bit hairy. This requires the multiple-chip SLS feature, which is an important one for large wall displays and systems that need high performance when
multi-GPU systems are configured with one or, alternatively, with two or more SLS areas, or even multiple SLS areas plus some single-monitor xscreens, as is possible with Accelerated-X HS Series.
The Summit Series Editions have a utility to make the tast of configuring SLS systems relatively easy - even if Video Windows are involved, or even if some monitors are Rotated.
With SLS, one can configure "Hidden Pixels" in order to simulate the effect of looking through a multi-pane picture window. (See Hidden Pixel).The Multi-chip SLS feature that is implemented in the Summit Series provides full hardware acceleration for all monitor views.
Multi-chip SLS can be combined with rotated monitors (see the Rotation Feature), which is also a hardware-accelerated feature in the Summit Series. P
Summit HX Series - an SLS Workhorse
The HX Series was developed specifically for large wall displays that needed high performance, SLS capability, (even multiple SLSs on a single display), ease of configuration, (even with a mixture of SLSs and single xscreens), and the abiltiy to support up to six XVideo windows.
In a short time after it was introduced, it had become a hit. Auto and railroad control systems use it. Power grid control/monitoring systems use it. Process control systems use it. See the HX Series brochure, and the note on configuring HX.)
Number of Monitors on HX Series
The standard HX Series can support up to sixteen (16) monitors with a "Level 3" license. A Level 2 license will allow the HX Series system to support up to eight monitors, and Level 1 limits the number of monitors to four.
Larger systems tend to be more complex, and generally need more pre-sales and post-sales support of customers. Hence the "Level" system of licensing the HX series.
With sixteen monitors on an HX Series system, the configuration variations using multiple SLSs and multiple xscreens-per-monitor assignments is large.
Wall display systems that need more than sixteen monitors can be accomodated as a special. Contact us with your requirements, and we can go from there.