upstream-man-pages/man2/glStencilMaskSeparate.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="glStencilMaskSeparate">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>1991-2006</year>
   9                 <holder>Silicon Graphics, Inc.</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>glStencilMaskSeparate</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>glStencilMaskSeparate</refname>
  17         <refpurpose>control the front and/or back writing of individual bits in the stencil planes</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>void <function>glStencilMaskSeparate</function></funcdef>
  23                 <paramdef>GLenum <parameter>face</parameter></paramdef>
  24                 <paramdef>GLuint <parameter>mask</parameter></paramdef>
  25             </funcprototype>
  26         </funcsynopsis>
  27     </refsynopsisdiv>
  28     <!-- eqn: ignoring delim $$ -->
  29     <refsect1 id="parameters"><title>Parameters</title>
  30         <variablelist>
  31         <varlistentry>
  32             <term><parameter>face</parameter></term>
  33             <listitem>
  34                 <para>
  35                     Specifies whether the front and/or back stencil writemask is updated.
  36                     Three symbolic constants are valid:
  37                     <constant>GL_FRONT</constant>,
  38                     <constant>GL_BACK</constant>, and
  39                     <constant>GL_FRONT_AND_BACK</constant>.
  40                 </para>
  41             </listitem>
  42         </varlistentry>
  43         <varlistentry>
  44             <term><parameter>mask</parameter></term>
  45             <listitem>
  46                 <para>
  47                     Specifies a bit mask to enable and disable writing of individual bits
  48                     in the stencil planes.
  49                     Initially, the mask is all 1's.
  50                 </para>
  51             </listitem>
  52         </varlistentry>
  53         </variablelist>
  54     </refsect1>
  55     <refsect1 id="description"><title>Description</title>
  56         <para>
  57             <function>glStencilMaskSeparate</function> controls the writing of individual bits in the stencil planes.
  58             The least significant
  59             <inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>
  60             bits of <parameter>mask</parameter>,
  61             where
  62             <inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>
  63             is the number of bits in the stencil buffer,
  64             specify a mask.
  65             Where a 1 appears in the mask,
  66             it's possible to write to the corresponding bit in the stencil buffer.
  67             Where a 0 appears,
  68             the corresponding bit is write-protected.
  69             Initially, all bits are enabled for writing.
  70         </para>
  71         <para>
  72             There can be two separate <parameter>mask</parameter> writemasks; one affects back-facing polygons, and the other
  73             affects front-facing polygons as well as other non-polygon primitives.
  74             <citerefentry><refentrytitle>glStencilMask</refentrytitle></citerefentry> sets both front
  75             and back stencil writemasks to the same values, as if
  76             <citerefentry><refentrytitle>glStencilMaskSeparate</refentrytitle></citerefentry> were called
  77             with <parameter>face</parameter> set to <constant>GL_FRONT_AND_BACK</constant>.
  78         </para>
  79     </refsect1>
  80     <refsect1 id="notes"><title>Notes</title>
  81         <para>
  82             <function>glStencilMaskSeparate</function> is available only if
  83             the GL version is 2.0 or greater.
  84         </para>
  85     </refsect1>
  86     <refsect1 id="errors"><title>Errors</title>
  87         <para>
  88             <constant>GL_INVALID_OPERATION</constant> is generated if <function>glStencilMaskSeparate</function>
  89             is executed between the execution of <citerefentry><refentrytitle>glBegin</refentrytitle></citerefentry>
  90             and the corresponding execution of <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
  91         </para>
  92     </refsect1>
  93     <refsect1 id="associatedgets"><title>Associated Gets</title>
  94         <para>
  95             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument
  96             <constant>GL_STENCIL_WRITEMASK</constant>, <constant>GL_STENCIL_BACK_WRITEMASK</constant>,
  97             or <constant>GL_STENCIL_BITS</constant>
  98         </para>
  99     </refsect1>
 100     <refsect1 id="seealso"><title>See Also</title>
 101         <para>
 102             <citerefentry><refentrytitle>glColorMask</refentrytitle></citerefentry>,
 103             <citerefentry><refentrytitle>glDepthMask</refentrytitle></citerefentry>,
 104             <citerefentry><refentrytitle>glIndexMask</refentrytitle></citerefentry>,
 105             <citerefentry><refentrytitle>glStencilFunc</refentrytitle></citerefentry>,
 106             <citerefentry><refentrytitle>glStencilFuncSeparate</refentrytitle></citerefentry>,
 107             <citerefentry><refentrytitle>glStencilMask</refentrytitle></citerefentry>,
 108             <citerefentry><refentrytitle>glStencilOp</refentrytitle></citerefentry>,
 109             <citerefentry><refentrytitle>glStencilOpSeparate</refentrytitle></citerefentry>
 110         </para>
 111     </refsect1>
 112     <refsect1 id="Copyright"><title>Copyright</title>
 113         <para>
 114             Copyright <trademark class="copyright"></trademark> 2006 Khronos Group.
 115             This material may be distributed subject to the terms and conditions set forth in
 116             the Open Publication License, v 1.0, 8 June 1999.
 117             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
 118         </para>
 119     </refsect1>
 120 </refentry>