mspatt(3G)mspatt(3G)NAMEmspatt - specifies a multisample sample pattern
FORTRAN 77 SPECIFICATION
subroutine mspattern(pattern)
integer*4 pattern
PARAMETERS
pattern is one of several enumerated values:
MSPDEF
MSP2P0
MSP2P1
MSP4P0
MSP4P1
MSP4P2
MSP4P3
DESCRIPTION
By default multisample samples are located in a cluster surrounding each
pixel center. The default locations are chosen to produce an optimal
result in a single rendering pass. Higher image quality can be achieved,
however, if multiple multisample images are composed using the
accumulation buffer. To do this effectively, a different sample pattern
must be used for each rendering pass. mspatt allows these different
patterns to be specified.
Patterns MSP2P0 and MSP2P1 are designed to provide optimal results in a
2-pass rendering. Patterns MSP4P0 through MSP4P3 provide optimal results
in a 4-pass rendering. In both cases, the images resulting from each
pass should be accumulated with equal weights.
mspattern should be changed only between complete rendering passes. It
should not be changed between the time clear/czclear is called and the
time that the rendered image is complete.
mspatt selects the appropriate sample locations as a function of the
number of samples in the current multisample buffer. The configuration
of the multisample buffer should not be changed during the accumulation
of a single image.
mspatt is ignored when the multisample buffer is not enabled.
EXAMPLE
This example configures the framebuffer with both a multisample buffer
and an accumulation buffer.
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mspatt(3G)mspatt(3G)RGBmod();
double();
acsize(12);
mssize(4,32,0);
gconfi();
lsetde(getgco(GCMZMA),getgco(GCMZMI));
zfunct(ZFGEQU);
zbuffe(TRUE);
multis(TRUE);
mspatt(MSP2P0);
czclea(0,0);
/* draw the scene */
acbuf(ACCLRA,1.0);
mspatt(MSP_2PASS_1);
czclea(0,0);
/* draw the scene again */
acbuf(ACACCU,1.0);
acbuf(ACRETU,0.5);
swapbu();
SEE ALSO
msalph, msmask, mssize, multis
NOTE
IRIS-4D G, GT, GTX, VGX, and VGXT models, the Personal Iris, Indigo
Entry, Indy, XL, XS, XS24, XZ, Elan and Extreme systems do not support
mspatt.
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