| 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="glIndexMask"> |
| 5 | <refmeta> |
| 6 | <refmetainfo> |
| 7 | <copyright> |
| 8 | <year>1991-2006</year> |
| 9 | <holder>Silicon Graphics, Inc.</holder> |
| 10 | </copyright> |
| 11 | </refmetainfo> |
| 12 | <refentrytitle>glIndexMask</refentrytitle> |
| 13 | <manvolnum>3G</manvolnum> |
| 14 | </refmeta> |
| 15 | <refnamediv> |
| 16 | <refname>glIndexMask</refname> |
| 17 | <refpurpose>control the writing of individual bits in the color index buffers</refpurpose> |
| 18 | </refnamediv> |
| 19 | <refsynopsisdiv><title>C Specification</title> |
| 20 | <funcsynopsis> |
| 21 | <funcprototype> |
| 22 | <funcdef>void <function>glIndexMask</function></funcdef> |
| 23 | <paramdef>GLuint <parameter>mask</parameter></paramdef> |
| 24 | </funcprototype> |
| 25 | </funcsynopsis> |
| 26 | </refsynopsisdiv> |
| 27 | <!-- eqn: ignoring delim $$ --> |
| 28 | <refsect1 id="parameters"><title>Parameters</title> |
| 29 | <variablelist> |
| 30 | <varlistentry> |
| 31 | <term><parameter>mask</parameter></term> |
| 32 | <listitem> |
| 33 | <para> |
| 34 | Specifies a bit mask to enable and disable the writing of individual bits |
| 35 | in the color index buffers. |
| 36 | Initially, the mask is all 1's. |
| 37 | </para> |
| 38 | </listitem> |
| 39 | </varlistentry> |
| 40 | </variablelist> |
| 41 | </refsect1> |
| 42 | <refsect1 id="description"><title>Description</title> |
| 43 | <para> |
| 44 | <function>glIndexMask</function> controls the writing of individual bits in the color index buffers. |
| 45 | The least significant |
| 46 | <inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation> |
| 47 | bits of <parameter>mask</parameter>, |
| 48 | where |
| 49 | <inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation> |
| 50 | is the number of bits in a color index buffer, |
| 51 | specify a mask. |
| 52 | Where a 1 (one) appears in the mask, |
| 53 | it's possible to write to the corresponding bit in the color index |
| 54 | buffer (or buffers). |
| 55 | Where a 0 (zero) appears, |
| 56 | the corresponding bit is write-protected. |
| 57 | </para> |
| 58 | <para> |
| 59 | This mask is used only in color index mode, |
| 60 | and it affects only the buffers currently selected for writing |
| 61 | (see <citerefentry><refentrytitle>glDrawBuffer</refentrytitle></citerefentry>). |
| 62 | Initially, all bits are enabled for writing. |
| 63 | </para> |
| 64 | </refsect1> |
| 65 | <refsect1 id="errors"><title>Errors</title> |
| 66 | <para> |
| 67 | <constant>GL_INVALID_OPERATION</constant> is generated if <function>glIndexMask</function> |
| 68 | is executed between the execution of <citerefentry><refentrytitle>glBegin</refentrytitle></citerefentry> |
| 69 | and the corresponding execution of <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>. |
| 70 | </para> |
| 71 | </refsect1> |
| 72 | <refsect1 id="associatedgets"><title>Associated Gets</title> |
| 73 | <para> |
| 74 | <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_INDEX_WRITEMASK</constant> |
| 75 | </para> |
| 76 | </refsect1> |
| 77 | <refsect1 id="seealso"><title>See Also</title> |
| 78 | <para> |
| 79 | <citerefentry><refentrytitle>glColorMask</refentrytitle></citerefentry>, |
| 80 | <citerefentry><refentrytitle>glDepthMask</refentrytitle></citerefentry>, |
| 81 | <citerefentry><refentrytitle>glDrawBuffer</refentrytitle></citerefentry>, |
| 82 | <citerefentry><refentrytitle>glIndex</refentrytitle></citerefentry>, |
| 83 | <citerefentry><refentrytitle>glIndexPointer</refentrytitle></citerefentry>, |
| 84 | <citerefentry><refentrytitle>glStencilMask</refentrytitle></citerefentry> |
| 85 | </para> |
| 86 | </refsect1> |
| 87 | <refsect1 id="Copyright"><title>Copyright</title> |
| 88 | <para> |
| 89 | Copyright <trademark class="copyright"></trademark> 1991-2006 |
| 90 | Silicon Graphics, Inc. This document is licensed under the SGI |
| 91 | Free Software B License. For details, see |
| 92 | <ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>. |
| 93 | </para> |
| 94 | </refsect1> |
| 95 | </refentry> |