upstream-doc/manglsl/gl_SampleMaskIn.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
   3               "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
   4 <refentry id="gl_SampleMaskIn">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>2011</year>
   9                 <holder>Khronos Group</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>gl_SampleMaskIn</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>gl_SampleMaskIn</refname>
  17         <refpurpose>contains the computed sample coverage mask for the current fragment</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>Declaration</title>
  20         <funcsynopsis>
  21             <function>in int gl_SampleMaskIn[];</function>
  22         </funcsynopsis>
  23     </refsynopsisdiv>
  24     <refsect1 id="description"><title>Description</title>
  25         <para>
  26             <function>gl_SampleMaskIn</function> is a fragment language that indicates the
  27             set of samples covered by the primitive generating the fragment during
  28             multisample rasterization. It has a sample bit set if and only if the sample
  29             is considered covered for this fragment shader invocation. Bit
  30             <emphasis>B</emphasis> of mask <function>gl_SampleMask[M]</function>
  31             corresponds to sample 32 * <emphasis>M</emphasis> + <emphasis>B</emphasis>.
  32             The array has <function>ceil</function>(<emphasis>s</emphasis> / 32) elements
  33             where <emphasis>s</emphasis> is the maximum number of color samples supported
  34             by the implementation.
  35         </para>
  36     </refsect1>
  37     <refsect1 id="versions"><title>Version Support</title>
  38         <informaltable frame="topbot">
  39             <tgroup cols="10" align="left">
  40                 <colspec colwidth="1.1*" />
  41                 <colspec colwidth="1*" align="center" />
  42                 <colspec colwidth="1*" align="center" />
  43                 <colspec colwidth="1*" align="center" />
  44                 <colspec colwidth="1*" align="center" />
  45                 <colspec colwidth="1*" align="center" />
  46                 <colspec colwidth="1*" align="center" />
  47                 <colspec colwidth="1*" align="center" />
  48                 <colspec colwidth="1*" align="center" />
  49                 <colspec colwidth="1*" align="center" />
  50                 <thead>
  51                     #VARTABLEHEADER#
  52                     <row>
  53                         <entry>
  54                             gl_SampleMaskIn
  55                         </entry>
  56                         #newin40#
  57                     </row>
  58                 </thead>
  59             </tgroup>
  60         </informaltable>
  61     </refsect1>
  62     <refsect1 id="seealso"><title>See Also</title>
  63         <para>
  64             <citerefentry><refentrytitle>gl_SampleMask</refentrytitle></citerefentry>,
  65             <citerefentry><refentrytitle>gl_SampleID</refentrytitle></citerefentry>,
  66             <citerefentry><refentrytitle>gl_SamplePosition</refentrytitle></citerefentry>,
  67             <citerefentry><refentrytitle>gl_FragCoord</refentrytitle></citerefentry>
  68         </para>
  69     </refsect1>
  70     <refsect1 id="Copyright"><title>Copyright</title>
  71         <para>
  72             Copyright <trademark class="copyright"></trademark> 2011 Khronos Group.
  73             This material may be distributed subject to the terms and conditions set forth in
  74             the Open Publication License, v 1.0, 8 June 1999.
  75             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
  76         </para>
  77     </refsect1>
  78 </refentry>