Sun Microsystems XVR-1200, Installation And User Manual

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38 Sun XVR-1200 Graphics Accelerator Installation and User’s Guide • July 2004
Multisampling
Multisample allocation occurs when the system is started or restarted. The
configuration samples-per-pixel parameter specifies the depth that is pre-allocated.
TABLE 5-1
describes the
fbconfig -multisample
options.
-multisample
[
available | disable | forceon
]
Sample Density
The
-samples
option specifies the number of samples per pixel to allocate when
multisample is not set to
disable
. The available
-sample
sizes are 1, 2, 4, 8, or 16.
-samples [1 | 2 | 4 | 8 | 16 | adaptive]
The maximum sample size is 16 samples per pixel. Using
-samples 16
, the sample
size is automatically allocated based on the frame buffer memory and video
resources available to the stream as the window system starts up. Though the
allowable choices are 1 to 16, a very high sample density can be allocated only at low
resolution. See “Disabling Multisampling” on page 39.
The
adaptive
option is the default setting for
-samples
. When you use the
-samples adaptive
option, two samples are preallocated per pixel (extra samples
are then assigned to pixels that need it).
See
TABLE 1-1
on page 5 for a list of how many samples per pixel are supported at
various maximum 3D resolutions. The
TABLE 1-1
heading “Dual screen” refers to
doublewide or doublehigh displays.
3. Log out, then log back in to restart the X window system for the changes to take
effect.
TABLE 5-1
Multisample Options
Option Description
available
Multisample is possible but is selected on a per application basis. A
fixed numbers of samples is used per pixel.
disable
No multisample is possible.
disable
is the default.
forceon
Multisampling for all Sun OpenGL for Solaris windows. A fixed
number of samples is used per pixel.
forceon
is the default.
(
force
is an acceptable abbreviation for this option.)