Multi-Screen Support |
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The list of supported multi-display configurations is rather
large, and it changes whenever a new graphics device is introduced.
Thus, if you are considering a Single Logical Screen or any other
multi-display configuration, we recommend consulting your HP Sales
Representative and inquiring whether the configuration you have
in mind is indeed supported.
There are general guidelines, however. For example:
Multi-display configurations may be
limited by available power. Depending on the capacity of your computer's
power supply, and the power demands of the combination of graphics
cards you are considering, there may or may not be enough power
to operate them all.
Single Logical Screen configurations must use identical
graphics devices (see the next section).
Single Logical Screen (SLS) |
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SLS is a mechanism for treating homogeneous multi-display
configurations as a single "logical" screen. This allows the moving/spanning
of windows across multiple physical monitors. The word "homogeneous"
is included because SLS only works if the graphics devices included
in the SLS Configuration are of the same type. Note that on-board
and "card" versions of the same device can be considered identical;
for example, you could use an on-board
HP Visualize-EG graphics device and an HP Visualize-EG
graphics card, and still consider them
identical devices, thus permitting a 1×2 SLS or a 2×1
SLS.
SLS is enabled by using SAM (the System Administration Manager
tool, /usr/sbin/sam).
To enable an SLS configuration, start SAM, and follow the instructions
below:
Double-click on the "X Server Configuration"
button. A window entitled "Graphics" appears, containing an icon
for every graphics device on your system.
Select the devices you want to combine into an SLS
(click the mouse on the first device, and [Ctrl]-click on the others).
At this point, all the devices you want to combine into an SLS configuration
should be highlighted.
From the "Actions" menu, choose the menu item "Modify
Multi-Screen Layout". A dialog box appears, allowing you to specify
exactly how you want your SLS configuration to be.
Note that if your machine has only one graphics device, the
"Modify Multi-Screen Layout" menu option does not even appear, since
multiple devices cannot occur in a single-device context.
Note also that DHA (Direct Hardware Access) is not supported
in a window that spans multiple screens. This means, for example,
that while graphics is supported to a window spanning two or more
screens, accelerated graphics is not.
"Spanning," in this context, includes a window that is two or more
screens in size, as well as a window that is partially on one screen
and partially on another (even though it would fit on a single screen
if it were moved).
SLS can also be enabled via the /etc/X11/X*screens
file via the syntax:
SingleLogicalScreen n m
/dev/crt0 ... /dev/crtk |
Title not available (Single Logical Screen (SLS) )
- where:
n
= the number of "rows" in the physical configuration, m
= the number of "columns" in the physical configuration, and the
product of n×
m
is less than or equal to four.
For example, to create a logical screen that is one monitor
tall by two monitors wide, the following syntax would be used:
SingleLogicalScreen 1 2
/dev/crt0 /dev/crt1 |
Whereas for a logical screen that is two monitors tall by
one monitor wide, the syntax is:
SingleLogicalScreen 2 1
/dev/crt0 /dev/crt1 |
3D Acceleration and Single Logical Screen
Currently, SLS does not take advantage of 3D acceleration
(e.g. CRX-24Z). 3D applications (from any supported HP 3D API) will
continue to run with SLS; However, 3D performance with SLS will
be much slower than it is without SLS.
HP VUE/CDE and Single Logical Screen
Please note that HP VUE/CDE has not been modified to take
advantage of the Single Logical Screen capability. When presenting
information on your display, HP VUE may split a window across physical
screens. Examples include:
Window move and resize boxes.
This behavior is the result of HP VUE's naive assumption that
it is running against one large screen; it centers these windows
accordingly.
If you are using the default HP VUE key bindings, you can
easily reposition the Front Panel so that it is completely contained
within one physical screen:
With the input focus on the Front Panel, press AltSpace
(on older keyboards, use Extend Char
Space).
With the Front Panel menu posted and the "Move"
menu item selected, press Enter
(on older keyboards, Return)
to start the move.
Use the mouse or the arrow keys to reposition the
Front Panel to the desired location.
Press Enter (or
Return) to complete the move.
You may instead press Esc to
cancel the move.
Afterwards, this setting will be remembered and restored at
your next login. If you have previously set a Home session, you
will need to re-set the Home session in the Style Manager to register
the new Front Panel position.
Note that there is no mechanism in HP VUE for repositioning
the login screen, window move/resize boxes, or the screen lock dialog.
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