mspattern(3G)mspattern(3G)NAMEmspattern - specifies a multisample sample pattern
C SPECIFICATION
void mspattern(long pattern)
PARAMETERS
pattern is one of several enumerated values:
MSP_DEFAULT
MSP_2PASS_0
MSP_2PASS_1
MSP_4PASS_0
MSP_4PASS_1
MSP_4PASS_2
MSP_4PASS_3
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. mspattern allows these different
patterns to be specified.
Patterns MSP_2PASS_0 and MSP_2PASS_1 are designed to provide optimal
results in a 2-pass rendering. Patterns MSP_4PASS_0 through MSP_4PASS_3
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.
mspattern 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.
mspattern is ignored when the multisample buffer is not enabled.
EXAMPLE
This example configures the framebuffer with both a multisample buffer
and an accumulation buffer.
RGBmode();
doublebuffer();
acsize(12);
mssize(4,32,0);
gconfig();
lsetdepth(getgconfig(GC_MS_ZMAX),getgconfig(GC_MS_ZMIN));
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mspattern(3G)mspattern(3G)zfunction(ZF_GEQUAL);
zbuffer(TRUE);
multisample(TRUE);
mspattern(MSP_2PASS_0);
czclear(0,0);
/* draw the scene */
acbuf(AC_CLEAR_ACCUMULATE,1.0);
mspattern(MSP_2PASS_1);
czclear(0,0);
/* draw the scene again */
acbuf(AC_ACCUMULATE,1.0);
acbuf(AC_RETURN,0.5);
swapbuffers();
SEE ALSO
msalpha, msmask, mssize, multisample
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
mspattern.
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