NAME¶
gl_SampleMask - specifies the sample coverage mask for the current fragment
DECLARATION¶
out int gl_SampleMask[] ;.SH "DESCRIPTION"
gl_SampleMask is a fragment language output array that may be used to set
the sample mask for the fragment being processed. Coverage for the current
fragment will become the logical AND of the coverage mask and the output
gl_SampleMask. That is, setting a bit in
gl_SampleMask to zero
will cause the corresponding sample to be considered uncovered for the
purposes of multisample fragment operations. However, setting sample mask bits
back to one will never enable samples not covered by the original primitive.
Bit
B of mask
gl_SampleMask[M] corresponds to sample 32 *
M +
B. This array must be sized in the fragment shader either
implicitly or explicitly to be the same size as the implementation-dependent
maximum sample-mask (as an array of 32-bit elements), determined by the
maximum number of samples. If the fragment shader statically assigns a value
to
gl_SampleMask, the sample mask will be undefined for any array
elements of any fragment shader invocation that fails to assign a value. If a
shader does not statically assign a value to
gl_SampleMask, the sample
mask has no effect on the processing of a fragment. If the fragment shader is
being evaluated at any frequency other than per-fragment, bits within the
sample mask not corresponding to the current fragment shader invocation are
ignored.
VERSION SUPPORT¶
|
OpenGL Shading Language Version |
|
|
|
|
|
|
|
|
|
|
|
Variable Name |
1.10 |
1.20 |
1.30 |
1.40 |
1.50 |
3.30 |
4.00 |
4.10 |
4.20 |
4.30 |
4.40 |
4.50 |
gl_SampleMask |
- |
- |
- |
- |
- |
- |
✔ |
✔ |
✔ |
✔ |
✔ |
✔ |
SEE ALSO¶
gl_SampleMaskIn(),
gl_SampleID(),
gl_SamplePosition(),
gl_FragCoord()
COPYRIGHT¶
Copyright © 2011-2014 Khronos Group. This material may be distributed
subject to the terms and conditions set forth in the Open Publication License,
v 1.0, 8 June 1999.
http://opencontent.org/openpub/.
COPYRIGHT¶
Copyright © 2011-2014 Khronos Group