Configuring Multiple Frame Buffers

C H A P T E R 3

This chapter describes procedures for setting up multiple frame buffers.

Configuring Multiple Frame Buffers Through the Xservers File

To run more than one frame buffer you must modify your Xservers file. The
Sun XVR-100 graphics accelerator device name is pfb (for example, pfb0 and pfb1 for two Sun XVR-100 graphics accelerator devices). To do this:

1. Become superuser and open the /etc/dt/config/Xservers file.

# cd /etc/dt/config
# vi + Xservers

If the /etc/dt/config/Xservers file does not exist, create the /etc/dt/config directory and copy the Xservers file from /usr/dt/config/Xservers to /etc/dt/config.

# mkdir -p /etc/dt/config
# cp /usr/dt/config/Xservers /etc/dt/config
# cd /etc/dt/config
# vi + Xservers

2. Modify the file by adding the device locations for the applicable frame buffers being used. See the following examples:

Enter the Xservers file content in one long line.

This example shows the Xservers configuration file modified for one
Sun XVR-500 graphics accelerator (ifb0) and one Sun XVR-100 graphics accelerator (pfb0):

:0 Local local_uid@console root /usr/openwin/bin/Xsun -dev /dev/fbs/ifb0 -dev /dev/fbs/pfb0

This example shows how to remove two Sun XVR-500 graphics accelerators and add one Sun XVR-100 graphics accelerator in the Xservers configuration file.

Old Xservers configuration file with two Sun XVR-500 graphics accelerators:

:0 Local local_uid@console root /usr/openwin/bin/Xsun -dev /dev/fbs/ifb0 defdepth 24 -dev /dev/fbs/ifb1 defdepth 24

New Xservers configuration file with one Sun XVR-100 graphics accelerator:

:0 Local local_uid@console root /usr/openwin/bin/Xsun -dev /dev/fbs/pfb0

3. Log out, then log back in.

If you are editing the Xservers file after completing installation, reboot your system.

Xinerama

Refer to the proper Xservers(1) man page and Xservers documentation for further information. Xinerama is an X window system feature available in Solaris 8 system software and subsequent compatible releases for Sun graphics boards including the Sun XVR-100 graphics accelerator.

Using Xinerama

When the window system is started in Xinerama mode, all windows can be seamlessly moved across screen boundaries, thus creating one large, super high-resolution, virtual display. With Sun OpenGL 1.3 for Solaris, or subsequent compatible releases, this functionality is extended to OpenGL applications. No recompilation is necessary for a legacy application to work with Xinerama mode across multiple screens, even if the application was compiled with an older version of Sun OpenGL for Solaris.

To enable Xinerama mode (single logical screen) on multiscreen displays, add +xinerama to the Xsun command line in the /etc/dt/config/Xservers file.

See the following example.

Note - Be sure to enter +xinerama after .../Xsun in the command line.

For example, as superuser, type:

# cd /etc/dt/config
# vi + Xservers

Enter the Xservers file content in one long line.

:0  Local local_uid@console root /usr/openwin/bin/Xsun +xinerama -dev /dev/fbs/pfb0 -dev /dev/fbs/pfb1

Setting Up Two Video Outputs Over One Large Frame Buffer, in “Invalid Cross-Reference Format”, describes an alternative to Xinerama, useful in some cases, where performance may be better.

Restrictions When Using Xinerama

Both screens must have the same visuals to be combined using Xinerama. In practice, this means they must be the same device (family).

Both screens that the X window system thinks are side by side must have the same height to be combined using Xinerama.

Both screens that the X window system thinks are above and below must have the same width to be combined using Xinerama.