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608 lines
33 KiB
XML
608 lines
33 KiB
XML
<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
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"http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
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<refentry id="glTexParameter">
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<refmeta>
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<refmetainfo>
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<copyright>
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<year>1991-2006</year>
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<holder>Silicon Graphics, Inc.</holder>
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</copyright>
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</refmetainfo>
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<refentrytitle>glTexParameter</refentrytitle>
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<manvolnum>3G</manvolnum>
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</refmeta>
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<refnamediv>
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<refname>glTexParameter</refname>
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<refpurpose>set texture parameters</refpurpose>
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</refnamediv>
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<refsynopsisdiv><title>C Specification</title>
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<funcsynopsis>
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<funcprototype>
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<funcdef>void <function>glTexParameterf</function></funcdef>
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<paramdef>GLenum <parameter>target</parameter></paramdef>
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<paramdef>GLenum <parameter>pname</parameter></paramdef>
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<paramdef>GLfloat <parameter>param</parameter></paramdef>
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</funcprototype>
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</funcsynopsis>
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<funcsynopsis>
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<funcprototype>
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<funcdef>void <function>glTexParameteri</function></funcdef>
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<paramdef>GLenum <parameter>target</parameter></paramdef>
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<paramdef>GLenum <parameter>pname</parameter></paramdef>
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<paramdef>GLint <parameter>param</parameter></paramdef>
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</funcprototype>
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</funcsynopsis>
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</refsynopsisdiv>
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<!-- eqn: ignoring delim $$ -->
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<refsect1 id="parameters"><title>Parameters</title>
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<variablelist>
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<varlistentry>
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<term><parameter>target</parameter></term>
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<listitem>
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<para>
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Specifies the target texture of the active texture unit,
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which must be either <constant>GL_TEXTURE_2D</constant> or
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<constant>GL_TEXTURE_CUBE_MAP</constant>.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><parameter>pname</parameter></term>
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<listitem>
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<para>
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Specifies the symbolic name of a single-valued texture parameter.
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<parameter>pname</parameter> can be one of the following:
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<constant>GL_TEXTURE_MIN_FILTER</constant>,
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<constant>GL_TEXTURE_MAG_FILTER</constant>,
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<constant>GL_TEXTURE_WRAP_S</constant>, or
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<constant>GL_TEXTURE_WRAP_T</constant>.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><parameter>param</parameter></term>
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<listitem>
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<para>
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Specifies the value of <parameter>pname</parameter>.
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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</refsect1>
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<refsynopsisdiv><title>C Specification</title>
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<funcsynopsis>
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<funcprototype>
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<funcdef>void <function>glTexParameterfv</function></funcdef>
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<paramdef>GLenum <parameter>target</parameter></paramdef>
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<paramdef>GLenum <parameter>pname</parameter></paramdef>
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<paramdef>const GLfloat * <parameter>params</parameter></paramdef>
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</funcprototype>
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</funcsynopsis>
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<funcsynopsis>
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<funcprototype>
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<funcdef>void <function>glTexParameteriv</function></funcdef>
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<paramdef>GLenum <parameter>target</parameter></paramdef>
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<paramdef>GLenum <parameter>pname</parameter></paramdef>
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<paramdef>const GLint * <parameter>params</parameter></paramdef>
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</funcprototype>
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</funcsynopsis>
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</refsynopsisdiv>
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<refsect1 id="parameters2"><title>Parameters</title>
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<variablelist>
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<varlistentry>
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<term><parameter>target</parameter></term>
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<listitem>
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<para>
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Specifies the target texture of the active texture unit,
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which must be either <constant>GL_TEXTURE_2D</constant> or
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<constant>GL_TEXTURE_CUBE_MAP</constant>.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><parameter>pname</parameter></term>
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<listitem>
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<para>
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Specifies the symbolic name of a texture parameter.
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<parameter>pname</parameter> can be one of the following:
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<constant>GL_TEXTURE_MIN_FILTER</constant>,
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<constant>GL_TEXTURE_MAG_FILTER</constant>,
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<constant>GL_TEXTURE_WRAP_S</constant>, or
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<constant>GL_TEXTURE_WRAP_T</constant>.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><parameter>params</parameter></term>
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<listitem>
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<para>
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Specifies a pointer to an array where the value of
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<parameter>pname</parameter> is stored.
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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</refsect1>
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<refsect1 id="description"><title>Description</title>
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<para>
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Texture mapping is a technique that applies an image onto an object's surface
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as if the image were a decal or cellophane shrink-wrap.
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The image is created in texture space,
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with an
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(<inlineequation><mml:math><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>,
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<inlineequation><mml:math><mml:mi mathvariant="italic">t</mml:mi></mml:math></inlineequation>)
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coordinate system.
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A texture is a two-dimensional or cube-mapped image and a set of parameters
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that determine how samples are derived from the image.
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</para>
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<para>
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<function>glTexParameter</function> assigns the value or values in <parameter>params</parameter> to the texture parameter
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specified as <parameter>pname</parameter>.
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<parameter>target</parameter> defines the target texture of the active texture unit,
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either <constant>GL_TEXTURE_2D</constant> or <constant>GL_TEXTURE_CUBE_MAP</constant>.
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The following symbols are accepted in <parameter>pname</parameter>:
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</para>
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<variablelist>
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<varlistentry>
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<term><constant>GL_TEXTURE_MIN_FILTER</constant></term>
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<listitem>
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<para>
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The texture minifying function is used whenever the pixel being textured
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maps to an area greater than one texture element.
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There are six defined minifying functions.
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Two of them use the nearest one or nearest four texture elements
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to compute the texture value.
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The other four use mipmaps.
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</para>
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<para>
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A mipmap is an ordered set of arrays representing the same image
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at progressively lower resolutions.
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If the texture has dimensions
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<inlineequation><mml:math>
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<!-- eqn: w times h:-->
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<mml:mrow>
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<mml:mi mathvariant="italic">w</mml:mi>
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<mml:mo>×</mml:mo>
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<mml:mi mathvariant="italic">h</mml:mi>
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</mml:mrow>
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</mml:math></inlineequation>,
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there are
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<inlineequation><mml:math>
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<!-- eqn: floor ( log sub 2 ( max ( w, h ) ) ) + 1:-->
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<mml:mrow>
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<mml:mrow>
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<mml:mi mathvariant="italic">floor</mml:mi>
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<mml:mo>⁡</mml:mo>
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<mml:mfenced open="(" close=")">
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<mml:mrow>
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<mml:msub><mml:mi mathvariant="italic">log</mml:mi>
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<mml:mn>2</mml:mn>
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</mml:msub>
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<mml:mo>⁡</mml:mo>
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<mml:mfenced open="(" close=")">
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<mml:mrow>
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<mml:mi mathvariant="italic">max</mml:mi>
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<mml:mo>⁡</mml:mo>
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<mml:mfenced open="(" close=")">
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<mml:mi mathvariant="italic">w</mml:mi>
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<mml:mi mathvariant="italic">h</mml:mi>
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</mml:mfenced>
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</mml:mrow>
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</mml:mfenced>
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</mml:mrow>
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</mml:mfenced>
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</mml:mrow>
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<mml:mo>+</mml:mo>
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<mml:mn>1</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>
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mipmap levels.
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The first mipmap level is the original texture,
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with dimensions
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<inlineequation><mml:math>
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<!-- eqn: w times h:-->
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<mml:mrow>
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<mml:mi mathvariant="italic">w</mml:mi>
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<mml:mo>×</mml:mo>
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<mml:mi mathvariant="italic">h</mml:mi>
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</mml:mrow>
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</mml:math></inlineequation>.
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Each subsequent mipmap level has dimensions
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<inlineequation><mml:math>
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<!-- eqn: max ( 1, floor ( w over 2 sup i ) ) times max ( 1, floor ( h over 2 sup i ) ):-->
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<mml:mrow>
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<mml:mi mathvariant="italic">max</mml:mi>
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<mml:mo>⁡</mml:mo>
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<mml:mfenced open="(" close=")">
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<mml:mn>1</mml:mn>
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<mml:mrow>
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<mml:mi mathvariant="italic">floor</mml:mi>
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<mml:mo>⁡</mml:mo>
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<mml:mfenced open="(" close=")">
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<mml:mfrac>
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<mml:mi mathvariant="italic">w</mml:mi>
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<mml:msup><mml:mn>2</mml:mn>
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<mml:mi mathvariant="italic">i</mml:mi>
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</mml:msup>
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</mml:mfrac>
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</mml:mfenced>
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</mml:mrow>
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</mml:mfenced>
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<mml:mo>×</mml:mo>
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<mml:mi mathvariant="italic">max</mml:mi>
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<mml:mo>⁡</mml:mo>
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<mml:mfenced open="(" close=")">
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<mml:mn>1</mml:mn>
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<mml:mrow>
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<mml:mi mathvariant="italic">floor</mml:mi>
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<mml:mo>⁡</mml:mo>
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<mml:mfenced open="(" close=")">
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<mml:mfrac>
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<mml:mi mathvariant="italic">h</mml:mi>
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<mml:msup><mml:mn>2</mml:mn>
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<mml:mi mathvariant="italic">i</mml:mi>
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</mml:msup>
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</mml:mfrac>
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</mml:mfenced>
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</mml:mrow>
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</mml:mfenced>
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</mml:mrow>
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</mml:math></inlineequation>,
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where
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<inlineequation><mml:math>
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<!-- eqn: i:-->
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<mml:mi mathvariant="italic">i</mml:mi>
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</mml:math></inlineequation>
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is the mipmap level,
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until the final mipmap is reached,
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which has dimension
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<inlineequation><mml:math>
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<!-- eqn: 1 times 1:-->
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<mml:mrow>
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<mml:mn>1</mml:mn>
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<mml:mo>×</mml:mo>
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<mml:mn>1</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>.
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</para>
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<para>
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To define the mipmap levels, call <citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>,
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<citerefentry><refentrytitle>glCompressedTexImage2D</refentrytitle></citerefentry>,
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or <citerefentry><refentrytitle>glCopyTexImage2D</refentrytitle></citerefentry>
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with the <emphasis>level</emphasis> argument indicating the order of the mipmaps.
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Level 0 is the original texture;
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level
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<inlineequation><mml:math>
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<!-- eqn: floor ( log sub 2 ( max ( w, h ) ) ):-->
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<mml:mrow>
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<mml:mi mathvariant="italic">floor</mml:mi>
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<mml:mo>⁡</mml:mo>
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<mml:mfenced open="(" close=")">
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<mml:mrow>
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<mml:msub><mml:mi mathvariant="italic">log</mml:mi>
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<mml:mn>2</mml:mn>
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</mml:msub>
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<mml:mo>⁡</mml:mo>
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<mml:mfenced open="(" close=")">
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<mml:mrow>
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<mml:mi mathvariant="italic">max</mml:mi>
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<mml:mo>⁡</mml:mo>
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<mml:mfenced open="(" close=")">
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<mml:mi mathvariant="italic">w</mml:mi>
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<mml:mi mathvariant="italic">h</mml:mi>
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</mml:mfenced>
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</mml:mrow>
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</mml:mfenced>
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</mml:mrow>
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</mml:mfenced>
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</mml:mrow>
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</mml:math></inlineequation>
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is the final
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<inlineequation><mml:math>
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<!-- eqn: 1 times 1:-->
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<mml:mrow>
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<mml:mn>1</mml:mn>
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<mml:mo>×</mml:mo>
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<mml:mn>1</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>
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mipmap.
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</para>
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<para>
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<parameter>params</parameter> supplies a function for minifying the texture as one of the
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following:
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<variablelist>
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<varlistentry>
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<term><constant>GL_NEAREST</constant></term>
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<listitem>
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<para>
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Returns the value of the texture element that is nearest
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(in Manhattan distance)
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to the center of the pixel being textured.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_LINEAR</constant></term>
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<listitem>
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<para>
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Returns the weighted average of the four texture elements
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that are closest to the center of the pixel being textured.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_NEAREST_MIPMAP_NEAREST</constant></term>
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<listitem>
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<para>
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Chooses the mipmap that most closely matches the size of the pixel
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being textured and uses the <constant>GL_NEAREST</constant> criterion
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(the texture element nearest to the center of the pixel)
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to produce a texture value.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_LINEAR_MIPMAP_NEAREST</constant></term>
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<listitem>
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<para>
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Chooses the mipmap that most closely matches the size of the pixel
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being textured and uses the <constant>GL_LINEAR</constant> criterion
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(a weighted average of the four texture elements that are closest
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to the center of the pixel)
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to produce a texture value.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_NEAREST_MIPMAP_LINEAR</constant></term>
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<listitem>
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<para>
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Chooses the two mipmaps that most closely match the size of the pixel
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being textured and uses the <constant>GL_NEAREST</constant> criterion
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(the texture element nearest to the center of the pixel)
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to produce a texture value from each mipmap.
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The final texture value is a weighted average of those two values.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_LINEAR_MIPMAP_LINEAR</constant></term>
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<listitem>
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<para>
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Chooses the two mipmaps that most closely match the size of the pixel
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being textured and uses the <constant>GL_LINEAR</constant> criterion
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(a weighted average of the four texture elements that are closest
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to the center of the pixel)
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to produce a texture value from each mipmap.
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The final texture value is a weighted average of those two values.
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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</para>
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<para>
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As more texture elements are sampled in the minification process,
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fewer aliasing artifacts will be apparent.
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While the <constant>GL_NEAREST</constant> and <constant>GL_LINEAR</constant> minification functions can be
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faster than the other four,
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they sample only one or four texture elements to determine the texture value
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of the pixel being rendered and can produce moire patterns
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or ragged transitions.
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The initial value of <constant>GL_TEXTURE_MIN_FILTER</constant> is
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<constant>GL_NEAREST_MIPMAP_LINEAR</constant>.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_TEXTURE_MAG_FILTER</constant></term>
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<listitem>
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<para>
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The texture magnification function is used when the pixel being textured
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maps to an area less than or equal to one texture element.
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It sets the texture magnification function to either <constant>GL_NEAREST</constant>
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or <constant>GL_LINEAR</constant> (see below). <constant>GL_NEAREST</constant> is generally faster
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than <constant>GL_LINEAR</constant>,
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but it can produce textured images with sharper edges
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because the transition between texture elements is not as smooth.
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The initial value of <constant>GL_TEXTURE_MAG_FILTER</constant> is <constant>GL_LINEAR</constant>.
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<variablelist>
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<varlistentry>
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<term><constant>GL_NEAREST</constant></term>
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<listitem>
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<para>
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Returns the value of the texture element that is nearest
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(in Manhattan distance)
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to the center of the pixel being textured.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_LINEAR</constant></term>
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<listitem>
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<para>
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Returns the weighted average of the four texture elements
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that are closest to the center of the pixel being textured.
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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<para>
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</para>
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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<para>
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</para>
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<variablelist>
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<varlistentry>
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<term><constant>GL_TEXTURE_WRAP_S</constant></term>
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<listitem>
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<para>
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Sets the wrap parameter for texture coordinate
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<inlineequation><mml:math><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>
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to either <constant>GL_CLAMP_TO_EDGE</constant>, <constant>GL_MIRRORED_REPEAT</constant>, or
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<constant>GL_REPEAT</constant>. <constant>GL_CLAMP_TO_EDGE</constant> causes
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<inlineequation><mml:math><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>
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coordinates to be clamped to the
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range
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<inlineequation><mml:math>
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<!-- eqn: left [ {1 over 2N}, 1 - {1 over 2N} right ]:-->
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<mml:mfenced open="[" close="]">
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<mml:mfenced open="" close="">
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<mml:mrow>
|
|
<mml:mfrac>
|
|
<mml:mn>1</mml:mn>
|
|
<mml:mn>2<mml:mi mathvariant="italic">N</mml:mi></mml:mn>
|
|
</mml:mfrac>
|
|
</mml:mrow>
|
|
</mml:mfenced>
|
|
<mml:mrow>
|
|
<mml:mn>1</mml:mn>
|
|
<mml:mo>-</mml:mo>
|
|
<mml:mfenced open="" close="">
|
|
<mml:mrow>
|
|
<mml:mfrac>
|
|
<mml:mn>1</mml:mn>
|
|
<mml:mn>2<mml:mi mathvariant="italic">N</mml:mi></mml:mn>
|
|
</mml:mfrac>
|
|
</mml:mrow>
|
|
</mml:mfenced>
|
|
</mml:mrow>
|
|
</mml:mfenced>
|
|
</mml:math></inlineequation>,
|
|
where
|
|
<inlineequation><mml:math><mml:mi mathvariant="italic">N</mml:mi></mml:math></inlineequation>
|
|
is the size
|
|
of the texture in the direction of clamping. <constant>GL_REPEAT</constant> causes the
|
|
integer part of the
|
|
<inlineequation><mml:math><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>
|
|
coordinate to be ignored; the GL uses only the
|
|
fractional part, thereby creating a repeating pattern.
|
|
<constant>GL_MIRRORED_REPEAT</constant> causes the
|
|
<inlineequation><mml:math><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>
|
|
coordinate to be set to the
|
|
fractional part of the texture coordinate if the integer part of
|
|
<inlineequation><mml:math><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>
|
|
is
|
|
even; if the integer part of
|
|
<inlineequation><mml:math><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>
|
|
is odd, then the
|
|
<inlineequation><mml:math><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>
|
|
texture coordinate is
|
|
set to
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: 1 - frac(s):-->
|
|
<mml:mrow>
|
|
<mml:mn>1</mml:mn>
|
|
<mml:mo>-</mml:mo>
|
|
<mml:mrow>
|
|
<mml:mi mathvariant="italic">frac</mml:mi>
|
|
<mml:mo>⁡</mml:mo>
|
|
<mml:mfenced open="(" close=")">
|
|
<mml:mi mathvariant="italic">s</mml:mi>
|
|
</mml:mfenced>
|
|
</mml:mrow>
|
|
</mml:mrow>
|
|
</mml:math></inlineequation>,
|
|
where
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: frac(s):-->
|
|
<mml:mrow>
|
|
<mml:mi mathvariant="italic">frac</mml:mi>
|
|
<mml:mo>⁡</mml:mo>
|
|
<mml:mfenced open="(" close=")">
|
|
<mml:mi mathvariant="italic">s</mml:mi>
|
|
</mml:mfenced>
|
|
</mml:mrow>
|
|
</mml:math></inlineequation>
|
|
represents the fractional part of
|
|
<inlineequation><mml:math><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>.
|
|
Initially,
|
|
<constant>GL_TEXTURE_WRAP_S</constant> is set to <constant>GL_REPEAT</constant>.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
<para>
|
|
</para>
|
|
<variablelist>
|
|
<varlistentry>
|
|
<term><constant>GL_TEXTURE_WRAP_T</constant></term>
|
|
<listitem>
|
|
<para>
|
|
Sets the wrap parameter for texture coordinate
|
|
<inlineequation><mml:math><mml:mi mathvariant="italic">t</mml:mi></mml:math></inlineequation>
|
|
to either <constant>GL_CLAMP_TO_EDGE</constant>, <constant>GL_MIRRORED_REPEAT</constant>, or
|
|
<constant>GL_REPEAT</constant>. See the discussion under <constant>GL_TEXTURE_WRAP_S</constant>.
|
|
Initially, <constant>GL_TEXTURE_WRAP_T</constant> is set to <constant>GL_REPEAT</constant>.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
</refsect1>
|
|
<refsect1 id="notes"><title>Notes</title>
|
|
<para>
|
|
Suppose that a texture is accessed from a fragment shader or vertex shader and
|
|
has set <constant>GL_TEXTURE_MIN_FILTER</constant> to one of the functions that requires
|
|
mipmaps. If either the dimensions of the texture images currently defined
|
|
(with previous calls to <citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glCompressedTexImage2D</refentrytitle></citerefentry>,
|
|
or <citerefentry><refentrytitle>glCopyTexImage2D</refentrytitle></citerefentry>) do not
|
|
follow the proper sequence for mipmaps (described above), or there are
|
|
fewer texture images defined than are needed, or the set of texture images
|
|
were defined with different formats or types, then the texture image unit will return
|
|
(R, G, B, A) = (0, 0, 0, 1).
|
|
</para>
|
|
<para>
|
|
Similarly, if the width or height of a texture image are not powers of two and either the
|
|
<constant>GL_TEXTURE_MIN_FILTER</constant> is set to one of the functions that requires mipmaps
|
|
or the <constant>GL_TEXTURE_WRAP_S</constant> or <constant>GL_TEXTURE_WRAP_T</constant> is not
|
|
set to <constant>GL_CLAMP_TO_EDGE</constant>, then the texture image unit will return
|
|
(R, G, B, A) = (0, 0, 0, 1).
|
|
</para>
|
|
<para>
|
|
<function>glTexParameter</function>
|
|
specifies the texture parameters for the texture bound to the active texture unit, specified
|
|
by calling <citerefentry><refentrytitle>glActiveTexture</refentrytitle></citerefentry>.
|
|
</para>
|
|
</refsect1>
|
|
<refsect1 id="errors"><title>Errors</title>
|
|
<para>
|
|
<constant>GL_INVALID_ENUM</constant> is generated if <parameter>target</parameter> or <parameter>pname</parameter> is not
|
|
one of the accepted defined values.
|
|
</para>
|
|
<para>
|
|
<constant>GL_INVALID_ENUM</constant> is generated if <parameter>params</parameter>
|
|
should have a defined symbolic
|
|
constant value (based on the value of <parameter>pname</parameter>) and does not.
|
|
</para>
|
|
</refsect1>
|
|
<refsect1 id="associatedgets"><title>Associated Gets</title>
|
|
<para>
|
|
<citerefentry><refentrytitle>glGetTexParameter</refentrytitle></citerefentry>
|
|
</para>
|
|
</refsect1>
|
|
<refsect1 id="seealso"><title>See Also</title>
|
|
<para>
|
|
<citerefentry><refentrytitle>glActiveTexture</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glBindTexture</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glCopyTexImage2D</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glCopyTexSubImage2D</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glPixelStorei</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glTexSubImage2D</refentrytitle></citerefentry>
|
|
</para>
|
|
</refsect1>
|
|
<refsect1 id="copyright"><title>Copyright</title>
|
|
<para>
|
|
Copyright <trademark class="copyright"></trademark> 1991-2006
|
|
Silicon Graphics, Inc. This document is licensed under the SGI
|
|
Free Software B License. For details, see
|
|
<ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>.
|
|
</para>
|
|
</refsect1>
|
|
</refentry>
|