Graphics Administration Guide (April 2009)

Figure 3-1 Results of minimal legal X*screens file
• This sample X*screens file could be used on a system using HP VISUALIZE-FXE with a
17-inch monitor. In this example, the GraphicsSharedMemorySize is decreased to 1 Mbyte
in order to reduce the swap space requirements of the system. Decreasing
GraphicsSharedMemorySize is appropriate when you do not intend to run any 3D graphics
applications.
ServerOptions
GraphicsSharedMemorySize 0x100000
Screen /dev/crt
MonitorSize 17 inches
The display diagram would be the same as that of the “Results of Minimal Legal X*screens
File” configuration, above.
• The overlay visual is selected as the default. There are 255 overlay colormap entries available
on the HP VISUALIZE-FXE. The 256th entry is hard-wired to transparent. Having less than
256 colormap entries should not cause a problem for most applications, but for those
applications that require 256 colormap entries, the CountTransparentInOverlayVisual screen
option should be used as shown below. Note that any attempts to modify the 256th entry
will have no effect on the colormap.
Screen /dev/crt
ScreenOptions
CountTransparentInOverlayVisual
The display diagram would be the same as that of the “Results of Minimal Legal X*screens
File” configuration, above.
• The default visual on the HP VISUALIZE-FXE is the opaque overlay visual. All 256 colormap
entries are opaque and allocable. If an application requires transparency in the default visual,
the “Transparent” keyword can be used to select the transparent overlay visual as shown
below.
Screen /dev/crt
DefaultVisual
Transparent
The display diagram would be the same as that of the “Results of Minimal Legal X*screens
File” configuration, above.
miscellaneous topics
double buffer extensions
DBE is an extension to the X Server that provides a double-buffering Application Programming
Interface (API). For more information about DBE and the API, consult the DBE man pages:
DBE
XdbeQueryExtension
XdbeGetVisualInfo
XdbeFreeVisualInfo
XdbeAllocateBackBufferName
XdbeDeallocateBackBufferName
XdbeSwapBuffers
XdbeBeginIdiom
XdbeEndIdiom
XdbeGetBackBufferAttributes
X Server configuration 35