C H A P T E R 4 - Configuring Multiple Frame Buffers

C H A P T E R 4

Configuring Multiple Frame Buffers

This chapter describes procedures for setting up multiple frame buffers.

Configuring Multiple Frame Buffers Through the Xservers File

Xinerama

Configuring Multiple Frame Buffers Through the Xservers File

To run more than one frame buffer you must modify your /etc/dt/config/Xservers file. The Sun XVR-1200 graphics accelerator device name is jfb (for example, jfb0 and jfb1 for two Sun XVR-1200 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:

Note - For Sun Fire 6800 systems, use local_uid@none instead of local_uid@console when configuring the Xservers file.

Enter the Xservers file content on a single line. See the following examples.

This example shows the Xservers configuration file modified for one
Sun XVR-500 graphics accelerator and one Sun XVR-1200 graphics accelerator:

:0 Local local_uid@console root /usr/openwin/bin/Xsun -dev /dev/fbs/ifb0 -dev /dev/fbs/jfb0

This example shows the Xservers configuration file modified for one
Sun XVR-1200 graphics accelerator:

:0 Local local_uid@console root /usr/openwin/bin/Xsun -dev /dev/fbs/jfb0

3. Log out, then log back in.

If you are editing the Xservers file after completing all the installation steps outlined in Chapter 1, Installation Process, including the reconfiguration, simply 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-1200 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 1.2.3 and 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.

For example, as superuser, type:

# cd /etc/dt/config

# vi + Xservers

:0  Local local_uid@console root /usr/openwin/bin/Xsun +xinerama -dev /dev/fbs /jfb0 -dev /dev/fbs/jfb1

Note - For Sun Fire 6800 systems, use local_uid@none instead of local_uid@console when configuring the Xservers file.

There is some affect to performance when using Xinerama. Setting Up Two Video Streams Over One Large Frame Buffer, in Chapter 5, describes an alternative to Xinerama which in some cases may improve performance.

Restrictions When Using Xinerama

Sample density is irrelevant to Xinerama. Therefore, screens of different sample density can be combined 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.