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<!DOCTYPE refentry [ <!ENTITY % mathent SYSTEM "math.ent"> %mathent; ]>
<!-- Converted by db4 - upgrade version 1.1 -->
<refentry xmlns= "http://docbook.org/ns/docbook" version= "5.0" xml:id= "glTexParameter" >
<info >
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<copyright >
<year > 1991-2006</year>
<holder > Silicon Graphics, Inc.</holder>
</copyright>
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<copyright >
<year > 2010-2014</year>
<holder > Khronos Group</holder>
</copyright>
</info>
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<refmeta >
<refentrytitle > glTexParameter</refentrytitle>
<manvolnum > 3G</manvolnum>
</refmeta>
<refnamediv >
<refname > glTexParameter</refname>
<refpurpose > set texture parameters</refpurpose>
</refnamediv>
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<refsynopsisdiv >
<title > C Specification</title>
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<funcsynopsis >
<funcprototype >
<funcdef > void <function > glTexParameterf</function> </funcdef>
<paramdef > GLenum <parameter > target</parameter> </paramdef>
<paramdef > GLenum <parameter > pname</parameter> </paramdef>
<paramdef > GLfloat <parameter > param</parameter> </paramdef>
</funcprototype>
</funcsynopsis>
<funcsynopsis >
<funcprototype >
<funcdef > void <function > glTexParameteri</function> </funcdef>
<paramdef > GLenum <parameter > target</parameter> </paramdef>
<paramdef > GLenum <parameter > pname</parameter> </paramdef>
<paramdef > GLint <parameter > param</parameter> </paramdef>
</funcprototype>
</funcsynopsis>
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<!-- Vector commands -->
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<funcsynopsis >
<funcprototype >
<funcdef > void <function > glTexParameterfv</function> </funcdef>
<paramdef > GLenum <parameter > target</parameter> </paramdef>
<paramdef > GLenum <parameter > pname</parameter> </paramdef>
<paramdef > const GLfloat * <parameter > params</parameter> </paramdef>
</funcprototype>
</funcsynopsis>
<funcsynopsis >
<funcprototype >
<funcdef > void <function > glTexParameteriv</function> </funcdef>
<paramdef > GLenum <parameter > target</parameter> </paramdef>
<paramdef > GLenum <parameter > pname</parameter> </paramdef>
<paramdef > const GLint * <parameter > params</parameter> </paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
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<refsect1 xml:id= "parameters" > <title > Parameters</title>
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<variablelist >
<varlistentry >
<term > <parameter > target</parameter> </term>
<listitem >
<para >
Specifies the target texture,
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which must be either <constant > GL_TEXTURE_2D</constant> ,
<constant > GL_TEXTURE_3D</constant> ,
<constant > GL_TEXTURE_2D_ARRAY</constant> ,
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or <constant > GL_TEXTURE_CUBE_MAP</constant> .
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</para>
</listitem>
</varlistentry>
<varlistentry >
<term > <parameter > pname</parameter> </term>
<listitem >
<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_BASE_LEVEL</constant> ,
<constant > GL_TEXTURE_COMPARE_FUNC</constant> ,
<constant > GL_TEXTURE_COMPARE_MODE</constant> ,
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<constant > GL_TEXTURE_MIN_FILTER</constant> ,
<constant > GL_TEXTURE_MAG_FILTER</constant> ,
<constant > GL_TEXTURE_MIN_LOD</constant> ,
<constant > GL_TEXTURE_MAX_LOD</constant> ,
<constant > GL_TEXTURE_MAX_LEVEL</constant> ,
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<constant > GL_TEXTURE_SWIZZLE_R</constant> ,
<constant > GL_TEXTURE_SWIZZLE_G</constant> ,
<constant > GL_TEXTURE_SWIZZLE_B</constant> ,
<constant > GL_TEXTURE_SWIZZLE_A</constant> ,
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<constant > GL_TEXTURE_WRAP_S</constant> ,
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<constant > GL_TEXTURE_WRAP_T</constant> , or
<constant > GL_TEXTURE_WRAP_R</constant> .
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</para>
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</listitem>
</varlistentry>
<varlistentry >
<term > <parameter > param</parameter> </term>
<listitem >
<para >
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Specifies the value of <parameter > pname</parameter> .
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</para>
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</listitem>
</varlistentry>
<varlistentry >
<term > <parameter > params</parameter> </term>
<listitem >
<para >
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For the vector commands, specifies a pointer to an array
where the value or values of
<parameter > pname</parameter> are stored.
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</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
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<refsect1 xml:id= "description" > <title > Description</title>
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<para >
<function > glTexParameter</function> assigns the value or values in <parameter > params</parameter> to the texture parameter
specified as <parameter > pname</parameter> .
<parameter > target</parameter> defines the target texture,
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either <constant > GL_TEXTURE_2D</constant> , <constant > GL_TEXTURE_CUBE_MAP</constant> ,
<constant > GL_TEXTURE_2D_ARRAY</constant> , or <constant > GL_TEXTURE_3D</constant> .
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The following symbols are accepted in <parameter > pname</parameter> :
</para>
<variablelist >
<varlistentry >
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<term > <constant > GL_TEXTURE_BASE_LEVEL</constant> </term>
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<listitem >
<para >
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Specifies the index of the lowest defined mipmap level. This is an
integer value. The initial value is 0.
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</para>
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</listitem>
</varlistentry>
</variablelist>
<para >
</para>
<variablelist >
<varlistentry >
<term > <constant > GL_TEXTURE_COMPARE_FUNC</constant> </term>
<listitem >
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<para >
Specifies the comparison operator used when <constant > GL_TEXTURE_COMPARE_MODE</constant> is
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set to <constant > GL_COMPARE_REF_TO_TEXTURE</constant> . Permissible values are:
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<informaltable >
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<tgroup cols= "2" align= "left" >
<colspec />
<colspec />
<thead >
<row >
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<entry >
<emphasis role= "bold" > Texture Comparison Function </emphasis>
</entry>
<entry >
<emphasis role= "bold" > Computed result </emphasis>
</entry>
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</row>
</thead>
<tbody >
<row >
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<entry >
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<constant > GL_LEQUAL</constant>
</entry>
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<entry >
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: result = left { cpile {1.0 above 0.0} lpile {r <= {D sub t} above r > {D sub t}}: -->
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<mml:mrow >
<mml:mi mathvariant= "italic" > result</mml:mi>
<mml:mo > =</mml:mo>
<mml:mfenced open= "{" close= "" >
<mml:mrow >
<mml:mtable >
<mml:mtr > <mml:mtd >
<mml:mn > 1.0</mml:mn>
</mml:mtd> </mml:mtr>
<mml:mtr > <mml:mtd >
<mml:mn > 0.0</mml:mn>
</mml:mtd> </mml:mtr>
</mml:mtable>
<mml:mo > ⁢ </mml:mo>
<mml:mtable >
<mml:mtr > <mml:mtd >
<mml:mrow >
<mml:mi mathvariant= "italic" > r</mml:mi>
<mml:mo > < =</mml:mo>
<mml:mfenced open= "" close= "" >
<mml:msub > <mml:mi mathvariant= "italic" > D</mml:mi>
<mml:mi mathvariant= "italic" > t</mml:mi>
</mml:msub>
</mml:mfenced>
</mml:mrow>
</mml:mtd> </mml:mtr>
<mml:mtr > <mml:mtd >
<mml:mrow >
<mml:mi mathvariant= "italic" > r</mml:mi>
<mml:mo > > </mml:mo>
<mml:mfenced open= "" close= "" >
<mml:msub > <mml:mi mathvariant= "italic" > D</mml:mi>
<mml:mi mathvariant= "italic" > t</mml:mi>
</mml:msub>
</mml:mfenced>
</mml:mrow>
</mml:mtd> </mml:mtr>
</mml:mtable>
</mml:mrow>
</mml:mfenced>
</mml:mrow>
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</mml:math> </inlineequation>
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</entry>
</row>
<row >
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<entry >
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<constant > GL_GEQUAL</constant>
</entry>
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<entry >
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: result = left { cpile {1.0 above 0.0} lpile {r <= {D sub t} above r > {D sub t}}: -->
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<mml:mrow >
<mml:mi mathvariant= "italic" > result</mml:mi>
<mml:mo > =</mml:mo>
<mml:mfenced open= "{" close= "" >
<mml:mrow >
<mml:mtable >
<mml:mtr > <mml:mtd >
<mml:mn > 1.0</mml:mn>
</mml:mtd> </mml:mtr>
<mml:mtr > <mml:mtd >
<mml:mn > 0.0</mml:mn>
</mml:mtd> </mml:mtr>
</mml:mtable>
<mml:mo > ⁢ </mml:mo>
<mml:mtable >
<mml:mtr > <mml:mtd >
<mml:mrow >
<mml:mi mathvariant= "italic" > r</mml:mi>
<mml:mo > > =</mml:mo>
<mml:mfenced open= "" close= "" >
<mml:msub > <mml:mi mathvariant= "italic" > D</mml:mi>
<mml:mi mathvariant= "italic" > t</mml:mi>
</mml:msub>
</mml:mfenced>
</mml:mrow>
</mml:mtd> </mml:mtr>
<mml:mtr > <mml:mtd >
<mml:mrow >
<mml:mi mathvariant= "italic" > r</mml:mi>
<mml:mo > < </mml:mo>
<mml:mfenced open= "" close= "" >
<mml:msub > <mml:mi mathvariant= "italic" > D</mml:mi>
<mml:mi mathvariant= "italic" > t</mml:mi>
</mml:msub>
</mml:mfenced>
</mml:mrow>
</mml:mtd> </mml:mtr>
</mml:mtable>
</mml:mrow>
</mml:mfenced>
</mml:mrow>
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</mml:math> </inlineequation>
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</entry>
</row>
<row >
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<entry >
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<constant > GL_LESS</constant>
</entry>
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<entry >
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: result = left { cpile {1.0 above 0.0} lpile {r <= {D sub t} above r > {D sub t}}: -->
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<mml:mrow >
<mml:mi mathvariant= "italic" > result</mml:mi>
<mml:mo > =</mml:mo>
<mml:mfenced open= "{" close= "" >
<mml:mrow >
<mml:mtable >
<mml:mtr > <mml:mtd >
<mml:mn > 1.0</mml:mn>
</mml:mtd> </mml:mtr>
<mml:mtr > <mml:mtd >
<mml:mn > 0.0</mml:mn>
</mml:mtd> </mml:mtr>
</mml:mtable>
<mml:mo > ⁢ </mml:mo>
<mml:mtable >
<mml:mtr > <mml:mtd >
<mml:mrow >
<mml:mi mathvariant= "italic" > r</mml:mi>
<mml:mo > < </mml:mo>
<mml:mfenced open= "" close= "" >
<mml:msub > <mml:mi mathvariant= "italic" > D</mml:mi>
<mml:mi mathvariant= "italic" > t</mml:mi>
</mml:msub>
</mml:mfenced>
</mml:mrow>
</mml:mtd> </mml:mtr>
<mml:mtr > <mml:mtd >
<mml:mrow >
<mml:mi mathvariant= "italic" > r</mml:mi>
<mml:mo > > =</mml:mo>
<mml:mfenced open= "" close= "" >
<mml:msub > <mml:mi mathvariant= "italic" > D</mml:mi>
<mml:mi mathvariant= "italic" > t</mml:mi>
</mml:msub>
</mml:mfenced>
</mml:mrow>
</mml:mtd> </mml:mtr>
</mml:mtable>
</mml:mrow>
</mml:mfenced>
</mml:mrow>
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</mml:math> </inlineequation>
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</entry>
</row>
<row >
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<entry >
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<constant > GL_GREATER</constant>
</entry>
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<entry >
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: result = left { cpile {1.0 above 0.0} lpile {r <= {D sub t} above r > {D sub t}}: -->
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<mml:mrow >
<mml:mi mathvariant= "italic" > result</mml:mi>
<mml:mo > =</mml:mo>
<mml:mfenced open= "{" close= "" >
<mml:mrow >
<mml:mtable >
<mml:mtr > <mml:mtd >
<mml:mn > 1.0</mml:mn>
</mml:mtd> </mml:mtr>
<mml:mtr > <mml:mtd >
<mml:mn > 0.0</mml:mn>
</mml:mtd> </mml:mtr>
</mml:mtable>
<mml:mo > ⁢ </mml:mo>
<mml:mtable >
<mml:mtr > <mml:mtd >
<mml:mrow >
<mml:mi mathvariant= "italic" > r</mml:mi>
<mml:mo > > </mml:mo>
<mml:mfenced open= "" close= "" >
<mml:msub > <mml:mi mathvariant= "italic" > D</mml:mi>
<mml:mi mathvariant= "italic" > t</mml:mi>
</mml:msub>
</mml:mfenced>
</mml:mrow>
</mml:mtd> </mml:mtr>
<mml:mtr > <mml:mtd >
<mml:mrow >
<mml:mi mathvariant= "italic" > r</mml:mi>
<mml:mo > < =</mml:mo>
<mml:mfenced open= "" close= "" >
<mml:msub > <mml:mi mathvariant= "italic" > D</mml:mi>
<mml:mi mathvariant= "italic" > t</mml:mi>
</mml:msub>
</mml:mfenced>
</mml:mrow>
</mml:mtd> </mml:mtr>
</mml:mtable>
</mml:mrow>
</mml:mfenced>
</mml:mrow>
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</mml:math> </inlineequation>
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</entry>
</row>
<row >
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<entry >
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<constant > GL_EQUAL</constant>
</entry>
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<entry >
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: result = left { cpile {1.0 above 0.0} lpile {r <= {D sub t} above r > {D sub t}}: -->
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<mml:mrow >
<mml:mi mathvariant= "italic" > result</mml:mi>
<mml:mo > =</mml:mo>
<mml:mfenced open= "{" close= "" >
<mml:mrow >
<mml:mtable >
<mml:mtr > <mml:mtd >
<mml:mn > 1.0</mml:mn>
</mml:mtd> </mml:mtr>
<mml:mtr > <mml:mtd >
<mml:mn > 0.0</mml:mn>
</mml:mtd> </mml:mtr>
</mml:mtable>
<mml:mo > ⁢ </mml:mo>
<mml:mtable >
<mml:mtr > <mml:mtd >
<mml:mrow >
<mml:mi mathvariant= "italic" > r</mml:mi>
<mml:mo > =</mml:mo>
<mml:mfenced open= "" close= "" >
<mml:msub > <mml:mi mathvariant= "italic" > D</mml:mi>
<mml:mi mathvariant= "italic" > t</mml:mi>
</mml:msub>
</mml:mfenced>
</mml:mrow>
</mml:mtd> </mml:mtr>
<mml:mtr > <mml:mtd >
<mml:mrow >
<mml:mi mathvariant= "italic" > r</mml:mi>
<mml:mo > ≠ </mml:mo>
<mml:mfenced open= "" close= "" >
<mml:msub > <mml:mi mathvariant= "italic" > D</mml:mi>
<mml:mi mathvariant= "italic" > t</mml:mi>
</mml:msub>
</mml:mfenced>
</mml:mrow>
</mml:mtd> </mml:mtr>
</mml:mtable>
</mml:mrow>
</mml:mfenced>
</mml:mrow>
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</mml:math> </inlineequation>
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</entry>
</row>
<row >
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<entry >
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<constant > GL_NOTEQUAL</constant>
</entry>
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<entry >
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: result = left { cpile {1.0 above 0.0} lpile {r <= {D sub t} above r > {D sub t}}: -->
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<mml:mrow >
<mml:mi mathvariant= "italic" > result</mml:mi>
<mml:mo > =</mml:mo>
<mml:mfenced open= "{" close= "" >
<mml:mrow >
<mml:mtable >
<mml:mtr > <mml:mtd >
<mml:mn > 1.0</mml:mn>
</mml:mtd> </mml:mtr>
<mml:mtr > <mml:mtd >
<mml:mn > 0.0</mml:mn>
</mml:mtd> </mml:mtr>
</mml:mtable>
<mml:mo > ⁢ </mml:mo>
<mml:mtable >
<mml:mtr > <mml:mtd >
<mml:mrow >
<mml:mi mathvariant= "italic" > r</mml:mi>
<mml:mo > ≠ </mml:mo>
<mml:mfenced open= "" close= "" >
<mml:msub > <mml:mi mathvariant= "italic" > D</mml:mi>
<mml:mi mathvariant= "italic" > t</mml:mi>
</mml:msub>
</mml:mfenced>
</mml:mrow>
</mml:mtd> </mml:mtr>
<mml:mtr > <mml:mtd >
<mml:mrow >
<mml:mi mathvariant= "italic" > r</mml:mi>
<mml:mo > =</mml:mo>
<mml:mfenced open= "" close= "" >
<mml:msub > <mml:mi mathvariant= "italic" > D</mml:mi>
<mml:mi mathvariant= "italic" > t</mml:mi>
</mml:msub>
</mml:mfenced>
</mml:mrow>
</mml:mtd> </mml:mtr>
</mml:mtable>
</mml:mrow>
</mml:mfenced>
</mml:mrow>
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</mml:math> </inlineequation>
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</entry>
</row>
<row >
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<entry >
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<constant > GL_ALWAYS</constant>
</entry>
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<entry >
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<inlineequation >
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<mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<mml:mrow >
<mml:mi mathvariant= "italic" > result</mml:mi>
<mml:mo > =</mml:mo>
<mml:mi > 1.0</mml:mi>
</mml:mrow>
</mml:math>
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</inlineequation>
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</entry>
</row>
<row >
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<entry >
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<constant > GL_NEVER</constant>
</entry>
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<entry >
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<inlineequation >
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<mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<mml:mrow >
<mml:mi mathvariant= "italic" > result</mml:mi>
<mml:mo > =</mml:mo>
<mml:mi > 0.0</mml:mi>
</mml:mrow>
</mml:math>
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</inlineequation>
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</entry>
</row>
</tbody>
</tgroup>
</informaltable>
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where <inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > r</mml:mi> </mml:math> </inlineequation>
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is the current interpolated texture coordinate, and
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: D sub t: -->
<mml:msub > <mml:mi mathvariant= "italic" > D</mml:mi>
<mml:mi mathvariant= "italic" > t</mml:mi>
</mml:msub>
</mml:math> </inlineequation>
is the depth texture value sampled from the currently bound depth texture.
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > result</mml:mi> </mml:math> </inlineequation>
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is assigned to the the red channel.
</para>
</listitem>
</varlistentry>
<varlistentry >
<term > <constant > GL_TEXTURE_COMPARE_MODE</constant> </term>
<listitem >
<para >
Specifies the texture comparison mode for currently bound depth textures.
That is, a texture whose internal format is <constant > GL_DEPTH_COMPONENT_*</constant> ; see
<citerefentry > <refentrytitle > glTexImage2D</refentrytitle> </citerefentry> )
Permissible values are:
<variablelist >
<varlistentry >
<term > <constant > GL_COMPARE_REF_TO_TEXTURE</constant> </term>
<listitem >
<para >
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Specifies that the interpolated and clamped
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > r</mml:mi> </mml:math> </inlineequation>
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texture coordinate should
be compared to the value in the currently bound depth texture. See the
discussion of <constant > GL_TEXTURE_COMPARE_FUNC</constant> for details of how the comparison
is evaluated. The result of the comparison is assigned to the red channel.
</para>
</listitem>
</varlistentry>
<varlistentry >
<term > <constant > GL_NONE</constant> </term>
<listitem >
<para >
Specifies that the red channel should be assigned the
appropriate value from the currently bound depth texture.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</listitem>
</varlistentry>
<varlistentry >
<term > <constant > GL_TEXTURE_MIN_FILTER</constant> </term>
<listitem >
<para >
The texture minifying function is used whenever the level-of-detail function
used when sampling from the texture determines that the texture should be minified.
There are six defined minifying functions.
Two of them use either the nearest texture elements or a weighted average of multiple texture elements
to compute the texture value.
The other four use mipmaps.
</para>
<para >
A mipmap is an ordered set of arrays representing the same image
at progressively lower resolutions.
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If the texture has dimensions
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: 2 sup n times 2 sup m: -->
<mml:mrow >
<mml:msup > <mml:mn > 2</mml:mn>
<mml:mi mathvariant= "italic" > n</mml:mi>
</mml:msup>
<mml:mo > × </mml:mo>
<mml:msup > <mml:mn > 2</mml:mn>
<mml:mi mathvariant= "italic" > m</mml:mi>
</mml:msup>
</mml:mrow>
</mml:math> </inlineequation> ,
there are
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: max ( n, m ) + 1: -->
<mml:mrow >
<mml:mrow >
<mml:mi mathvariant= "italic" > max</mml:mi>
<mml:mo > ⁡ </mml:mo>
<mml:mfenced open= "(" close= ")" >
<mml:mi mathvariant= "italic" > n</mml:mi>
<mml:mi mathvariant= "italic" > m</mml:mi>
</mml:mfenced>
</mml:mrow>
<mml:mo > +</mml:mo>
<mml:mn > 1</mml:mn>
</mml:mrow>
</mml:math> </inlineequation>
mipmaps.
The first mipmap is the original texture,
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with dimensions
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: 2 sup n times 2 sup m: -->
<mml:mrow >
<mml:msup > <mml:mn > 2</mml:mn>
<mml:mi mathvariant= "italic" > n</mml:mi>
</mml:msup>
<mml:mo > × </mml:mo>
<mml:msup > <mml:mn > 2</mml:mn>
<mml:mi mathvariant= "italic" > m</mml:mi>
</mml:msup>
</mml:mrow>
</mml:math> </inlineequation> .
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Each subsequent mipmap has dimensions
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: 2 sup { k - 1 } times 2 sup { l - 1 }: -->
<mml:mrow >
<mml:msup > <mml:mn > 2</mml:mn>
<mml:mfenced open= "" close= "" >
<mml:mrow >
<mml:mi mathvariant= "italic" > k</mml:mi>
<mml:mo > -</mml:mo>
<mml:mn > 1</mml:mn>
</mml:mrow>
</mml:mfenced>
</mml:msup>
<mml:mo > × </mml:mo>
<mml:msup > <mml:mn > 2</mml:mn>
<mml:mfenced open= "" close= "" >
<mml:mrow >
<mml:mi mathvariant= "italic" > l</mml:mi>
<mml:mo > -</mml:mo>
<mml:mn > 1</mml:mn>
</mml:mrow>
</mml:mfenced>
</mml:msup>
</mml:mrow>
</mml:math> </inlineequation> ,
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where
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: 2 sup k times 2 sup l: -->
<mml:mrow >
<mml:msup > <mml:mn > 2</mml:mn>
<mml:mi mathvariant= "italic" > k</mml:mi>
</mml:msup>
<mml:mo > × </mml:mo>
<mml:msup > <mml:mn > 2</mml:mn>
<mml:mi mathvariant= "italic" > l</mml:mi>
</mml:msup>
</mml:mrow>
</mml:math> </inlineequation>
are the dimensions of the previous mipmap,
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until either
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: k = 0: -->
<mml:mrow >
<mml:mi mathvariant= "italic" > k</mml:mi>
<mml:mo > =</mml:mo>
<mml:mn > 0</mml:mn>
</mml:mrow>
</mml:math> </inlineequation>
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or
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: l = 0: -->
<mml:mrow >
<mml:mi mathvariant= "italic" > l</mml:mi>
<mml:mo > =</mml:mo>
<mml:mn > 0</mml:mn>
</mml:mrow>
</mml:math> </inlineequation> .
At that point,
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subsequent mipmaps have dimension
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: 1 times 2 sup { l - 1 }: -->
<mml:mrow >
<mml:mn > 1</mml:mn>
<mml:mo > × </mml:mo>
<mml:msup > <mml:mn > 2</mml:mn>
<mml:mfenced open= "" close= "" >
<mml:mrow >
<mml:mi mathvariant= "italic" > l</mml:mi>
<mml:mo > -</mml:mo>
<mml:mn > 1</mml:mn>
</mml:mrow>
</mml:mfenced>
</mml:msup>
</mml:mrow>
</mml:math> </inlineequation>
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or
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: 2 sup { k - 1} times 1: -->
<mml:mrow >
<mml:msup > <mml:mn > 2</mml:mn>
<mml:mfenced open= "" close= "" >
<mml:mrow >
<mml:mi mathvariant= "italic" > k</mml:mi>
<mml:mo > -</mml:mo>
<mml:mn > 1</mml:mn>
</mml:mrow>
</mml:mfenced>
</mml:msup>
<mml:mo > × </mml:mo>
<mml:mn > 1</mml:mn>
</mml:mrow>
</mml:math> </inlineequation>
until the final mipmap,
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which has dimension
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: 1 times 1: -->
<mml:mrow >
<mml:mn > 1</mml:mn>
<mml:mo > × </mml:mo>
<mml:mn > 1</mml:mn>
</mml:mrow>
</mml:math> </inlineequation> .
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To define the mipmaps, call <citerefentry > <refentrytitle > glTexImage2D</refentrytitle> </citerefentry> ,
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<citerefentry > <refentrytitle > glTexImage3D</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.
Level 0 is the original texture;
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level
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: max ( n, m ): -->
<mml:mrow >
<mml:mi mathvariant= "italic" > max</mml:mi>
<mml:mo > ⁡ </mml:mo>
<mml:mfenced open= "(" close= ")" >
<mml:mi mathvariant= "italic" > n</mml:mi>
<mml:mi mathvariant= "italic" > m</mml:mi>
</mml:mfenced>
</mml:mrow>
</mml:math> </inlineequation>
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is the final
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: 1 times 1: -->
<mml:mrow >
<mml:mn > 1</mml:mn>
<mml:mo > × </mml:mo>
<mml:mn > 1</mml:mn>
</mml:mrow>
</mml:math> </inlineequation>
mipmap.
</para>
<para >
<parameter > params</parameter> supplies a function for minifying the texture as one of the
following:
<variablelist >
<varlistentry >
<term > <constant > GL_NEAREST</constant> </term>
<listitem >
<para >
Returns the value of the texture element that is nearest
(in Manhattan distance)
to the specified texture coordinates.
</para>
</listitem>
</varlistentry>
<varlistentry >
<term > <constant > GL_LINEAR</constant> </term>
<listitem >
<para >
Returns the weighted average of the four texture elements
that are closest to the specified texture coordinates.
These can include items wrapped or repeated from other parts of a texture,
depending on the values of <constant > GL_TEXTURE_WRAP_S</constant> and <constant > GL_TEXTURE_WRAP_T</constant> ,
and on the exact mapping.
</para>
</listitem>
</varlistentry>
<varlistentry >
<term > <constant > GL_NEAREST_MIPMAP_NEAREST</constant> </term>
<listitem >
<para >
Chooses the mipmap that most closely matches the size of the pixel
being textured and uses the <constant > GL_NEAREST</constant> criterion
(the texture element closest to the specified texture coordinates)
to produce a texture value.
</para>
</listitem>
</varlistentry>
<varlistentry >
<term > <constant > GL_LINEAR_MIPMAP_NEAREST</constant> </term>
<listitem >
<para >
Chooses the mipmap that most closely matches the size of the pixel
being textured and uses the <constant > GL_LINEAR</constant> criterion
(a weighted average of the four texture elements that are closest to the specified texture coordinates)
to produce a texture value.
</para>
</listitem>
</varlistentry>
<varlistentry >
<term > <constant > GL_NEAREST_MIPMAP_LINEAR</constant> </term>
<listitem >
<para >
Chooses the two mipmaps that most closely match the size of the pixel
being textured and uses the <constant > GL_NEAREST</constant> criterion
(the texture element closest to the specified texture coordinates )
to produce a texture value from each mipmap.
The final texture value is a weighted average of those two values.
</para>
</listitem>
</varlistentry>
<varlistentry >
<term > <constant > GL_LINEAR_MIPMAP_LINEAR</constant> </term>
<listitem >
<para >
Chooses the two mipmaps that most closely match the size of the pixel
being textured and uses the <constant > GL_LINEAR</constant> criterion
(a weighted average of the texture elements that are closest to the specified texture coordinates)
to produce a texture value from each mipmap.
The final texture value is a weighted average of those two values.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
<para >
As more texture elements are sampled in the minification process,
fewer aliasing artifacts will be apparent.
While the <constant > GL_NEAREST</constant> and <constant > GL_LINEAR</constant> minification functions can be
faster than the other four,
they sample only one or multiple texture elements to determine the texture value
of the pixel being rendered and can produce moire patterns
or ragged transitions.
The initial value of <constant > GL_TEXTURE_MIN_FILTER</constant> is
<constant > GL_NEAREST_MIPMAP_LINEAR</constant> .
</para>
</listitem>
</varlistentry>
</variablelist>
<para >
</para>
<variablelist >
<varlistentry >
<term > <constant > GL_TEXTURE_MAG_FILTER</constant> </term>
<listitem >
<para >
The texture magnification function is used whenever the level-of-detail function
used when sampling from the texture determines that the texture should be magified.
It sets the texture magnification function to either <constant > GL_NEAREST</constant>
or <constant > GL_LINEAR</constant> (see below). <constant > GL_NEAREST</constant> is generally faster
than <constant > GL_LINEAR</constant> ,
but it can produce textured images with sharper edges
because the transition between texture elements is not as smooth.
The initial value of <constant > GL_TEXTURE_MAG_FILTER</constant> is <constant > GL_LINEAR</constant> .
<variablelist >
<varlistentry >
<term > <constant > GL_NEAREST</constant> </term>
<listitem >
<para >
Returns the value of the texture element that is nearest
(in Manhattan distance)
to the specified texture coordinates.
</para>
</listitem>
</varlistentry>
<varlistentry >
<term > <constant > GL_LINEAR</constant> </term>
<listitem >
<para >
Returns the weighted average of the texture elements
that are closest to the specified texture coordinates.
These can include items wrapped or repeated from other parts of a texture,
depending on the values of <constant > GL_TEXTURE_WRAP_S</constant> and <constant > GL_TEXTURE_WRAP_T</constant> ,
and on the exact mapping.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</listitem>
</varlistentry>
</variablelist>
<para >
</para>
<variablelist >
<varlistentry >
<term > <constant > GL_TEXTURE_MIN_LOD</constant> </term>
<listitem >
<para >
Sets the minimum level-of-detail parameter. This floating-point value
limits the selection of highest resolution mipmap (lowest mipmap
level). The initial value is -1000.
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</para>
</listitem>
</varlistentry>
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</variablelist>
<para >
</para>
<variablelist >
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<varlistentry >
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<term > <constant > GL_TEXTURE_MAX_LOD</constant> </term>
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<listitem >
<para >
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Sets the maximum level-of-detail parameter. This floating-point value
limits the selection of the lowest resolution mipmap (highest mipmap
level). The initial value is 1000.
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</para>
</listitem>
</varlistentry>
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</variablelist>
<para >
</para>
<variablelist >
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<varlistentry >
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<term > <constant > GL_TEXTURE_MAX_LEVEL</constant> </term>
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<listitem >
<para >
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Sets the index of the highest defined mipmap level. This is an integer
value. The initial value is 1000.
</para>
</listitem>
</varlistentry>
</variablelist>
<para >
</para>
<variablelist >
<varlistentry >
<term > <constant > GL_TEXTURE_SWIZZLE_R</constant> </term>
<listitem >
<para >
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Sets the swizzle that will be applied to the <inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > r</mml:mi> </mml:math> </inlineequation>
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component of a texel before it is returned to the shader. Valid values for <parameter > param</parameter> are <constant > GL_RED</constant> ,
<constant > GL_GREEN</constant> , <constant > GL_BLUE</constant> , <constant > GL_ALPHA</constant> , <constant > GL_ZERO</constant> and
<constant > GL_ONE</constant> .
If <constant > GL_TEXTURE_SWIZZLE_R</constant> is <constant > GL_RED</constant> , the value for
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > r</mml:mi> </mml:math> </inlineequation> will be taken from the first
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channel of the fetched texel.
If <constant > GL_TEXTURE_SWIZZLE_R</constant> is <constant > GL_GREEN</constant> , the value for
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > r</mml:mi> </mml:math> </inlineequation> will be taken from the second
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channel of the fetched texel.
If <constant > GL_TEXTURE_SWIZZLE_R</constant> is <constant > GL_BLUE</constant> , the value for
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > r</mml:mi> </mml:math> </inlineequation> will be taken from the third
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channel of the fetched texel.
If <constant > GL_TEXTURE_SWIZZLE_R</constant> is <constant > GL_ALPHA</constant> , the value for
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > r</mml:mi> </mml:math> </inlineequation> will be taken from the fourth
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channel of the fetched texel.
If <constant > GL_TEXTURE_SWIZZLE_R</constant> is <constant > GL_ZERO</constant> , the value for
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > r</mml:mi> </mml:math> </inlineequation> will be subtituted with
<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mn > 0</mml:mn> </mml:math> </inlineequation> .
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If <constant > GL_TEXTURE_SWIZZLE_R</constant> is <constant > GL_ONE</constant> , the value for
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > r</mml:mi> </mml:math> </inlineequation> will be subtituted with
<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mn > 1</mml:mn> </mml:math> </inlineequation> for integer texture components, otherwise
<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mn > 1.0</mml:mn> </mml:math> </inlineequation> .
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The initial value is <constant > GL_RED</constant> .
</para>
</listitem>
</varlistentry>
</variablelist>
<para >
</para>
<variablelist >
<varlistentry >
<term > <constant > GL_TEXTURE_SWIZZLE_G</constant> </term>
<listitem >
<para >
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Sets the swizzle that will be applied to the <inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > g</mml:mi> </mml:math> </inlineequation>
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component of a texel before it is returned to the shader. Valid values for <parameter > param</parameter> and their effects are similar to
those of <constant > GL_TEXTURE_SWIZZLE_R</constant> .
The initial value is <constant > GL_GREEN</constant> .
</para>
</listitem>
</varlistentry>
</variablelist>
<para >
</para>
<variablelist >
<varlistentry >
<term > <constant > GL_TEXTURE_SWIZZLE_B</constant> </term>
<listitem >
<para >
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Sets the swizzle that will be applied to the <inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > b</mml:mi> </mml:math> </inlineequation>
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component of a texel before it is returned to the shader. Valid values for <parameter > param</parameter> and their effects are similar to
those of <constant > GL_TEXTURE_SWIZZLE_R</constant> .
The initial value is <constant > GL_BLUE</constant> .
</para>
</listitem>
</varlistentry>
</variablelist>
<para >
</para>
<variablelist >
<varlistentry >
<term > <constant > GL_TEXTURE_SWIZZLE_A</constant> </term>
<listitem >
<para >
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Sets the swizzle that will be applied to the <inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > a</mml:mi> </mml:math> </inlineequation>
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component of a texel before it is returned to the shader. Valid values for <parameter > param</parameter> and their effects are similar to
those of <constant > GL_TEXTURE_SWIZZLE_R</constant> .
The initial value is <constant > GL_ALPHA</constant> .
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</para>
</listitem>
</varlistentry>
</variablelist>
<para >
</para>
<para >
</para>
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<variablelist >
<varlistentry >
<term > <constant > GL_TEXTURE_WRAP_S</constant> </term>
<listitem >
<para >
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Sets the wrap parameter for texture coordinate
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > s</mml:mi> </mml:math> </inlineequation>
to either <constant > GL_CLAMP_TO_EDGE</constant> ,
<constant > GL_MIRRORED_REPEAT</constant> , or
<constant > GL_REPEAT</constant> . <constant > GL_CLAMP_TO_EDGE</constant> causes
<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <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 xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- eqn: left [ {1 over 2N}, 1 - {1 over 2N} right ]: -->
<mml:mfenced open= "[" close= "]" >
<mml:mfenced open= "" close= "" >
<mml:mrow >
<mml:mfrac >
<mml:mn > 1</mml:mn>
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<mml:mrow > <mml:mn > 2</mml:mn> <mml:mi mathvariant= "italic" > N</mml:mi> </mml:mrow>
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</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>
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<mml:mrow > <mml:mn > 2</mml:mn> <mml:mi mathvariant= "italic" > N</mml:mi> </mml:mrow>
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</mml:mfrac>
</mml:mrow>
</mml:mfenced>
</mml:mrow>
</mml:mfenced>
</mml:math> </inlineequation> ,
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where
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > N</mml:mi> </mml:math> </inlineequation>
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is the size
of the texture in the direction of clamping.
<constant > GL_REPEAT</constant> causes the
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integer part of the
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > s</mml:mi> </mml:math> </inlineequation>
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coordinate to be ignored; the GL uses only the
fractional part, thereby creating a repeating pattern.
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<constant > GL_MIRRORED_REPEAT</constant> causes the
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > s</mml:mi> </mml:math> </inlineequation>
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coordinate to be set to the
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fractional part of the texture coordinate if the integer part of
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > s</mml:mi> </mml:math> </inlineequation>
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is
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even; if the integer part of
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > s</mml:mi> </mml:math> </inlineequation>
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is odd, then the
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > s</mml:mi> </mml:math> </inlineequation>
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texture coordinate is
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set to
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- 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> ,
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where
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" >
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<!-- 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
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > s</mml:mi> </mml:math> </inlineequation> .
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Initially, <constant > GL_TEXTURE_WRAP_S</constant> is set to <constant > GL_REPEAT</constant> .
</para>
</listitem>
</varlistentry>
</variablelist>
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<para >
</para>
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<variablelist >
<varlistentry >
<term > <constant > GL_TEXTURE_WRAP_T</constant> </term>
<listitem >
<para >
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Sets the wrap parameter for texture coordinate
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <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> .
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Initially, <constant > GL_TEXTURE_WRAP_T</constant> is set to <constant > GL_REPEAT</constant> .
</para>
</listitem>
</varlistentry>
</variablelist>
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<para >
</para>
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<variablelist >
<varlistentry >
<term > <constant > GL_TEXTURE_WRAP_R</constant> </term>
<listitem >
<para >
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Sets the wrap parameter for texture coordinate
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<inlineequation > <mml:math xmlns:mml= "http://www.w3.org/1998/Math/MathML" overflow= "scroll" > <mml:mi mathvariant= "italic" > r</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> .
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Initially, <constant > GL_TEXTURE_WRAP_R</constant> is set to <constant > GL_REPEAT</constant> .
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
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<refsect1 xml:id= "notes" > <title > Notes</title>
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<para >
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Suppose that a program attempts to sample from a texture and
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has set <constant > GL_TEXTURE_MIN_FILTER</constant> to one of the functions that requires a
mipmap. If either the dimensions of the texture images currently defined
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(with previous calls to <citerefentry > <refentrytitle > glTexStorage2D</refentrytitle> </citerefentry> ,
<citerefentry > <refentrytitle > glTexImage2D</refentrytitle> </citerefentry> ,
<citerefentry > <refentrytitle > glTexStorage3D</refentrytitle> </citerefentry> ,
<citerefentry > <refentrytitle > glTexImage3D</refentrytitle> </citerefentry> ,
or <citerefentry > <refentrytitle > glCopyTexImage2D</refentrytitle> </citerefentry> ) do not
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follow the proper sequence for mipmaps (described above), or there are
fewer texture images defined than are needed, or the set of texture images
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have differing numbers of texture components, then the texture is considered <emphasis > incomplete</emphasis> .
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</para>
<para >
Linear filtering accesses the four nearest texture elements only in 2D
textures. In 1D textures, linear filtering accesses the two nearest
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texture elements. In 3D textures, linear filtering accesses the eight nearest
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texture elements.
</para>
<para >
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<function > glTexParameter</function> specifies the texture parameters for the texture object bound to the
active texture unit, specified by calling <citerefentry > <refentrytitle > glActiveTexture</refentrytitle> </citerefentry> .
2013-10-23 18:17:08 +00:00
</para>
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</refsect1>
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<refsect1 xml:id= "errors" > <title > Errors</title>
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<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
constant value (based on the value of <parameter > pname</parameter> ) and does not.
</para>
</refsect1>
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<refsect1 xml:id= "associatedgets" > <title > Associated Gets</title>
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<para >
<citerefentry > <refentrytitle > glGetTexParameter</refentrytitle> </citerefentry>
</para>
</refsect1>
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<refsect1 xml:id= "versions" >
<title > API Version Support</title>
<informaltable >
<tgroup cols= "4" align= "left" >
<xi:include xmlns:xi= "http://www.w3.org/2001/XInclude" href= "apifunchead.xml" xpointer= "xpointer(/*/*)" />
<tbody >
<row >
<entry > <function > glTexParameterf</function> </entry>
<xi:include xmlns:xi= "http://www.w3.org/2001/XInclude" href= "apiversion.xml" xpointer= "xpointer(/*/*[@role='es20']/*)" />
</row>
<row >
<entry > <function > glTexParameterfv</function> </entry>
<xi:include xmlns:xi= "http://www.w3.org/2001/XInclude" href= "apiversion.xml" xpointer= "xpointer(/*/*[@role='es20']/*)" />
</row>
<row >
<entry > <function > glTexParameteri</function> </entry>
<xi:include xmlns:xi= "http://www.w3.org/2001/XInclude" href= "apiversion.xml" xpointer= "xpointer(/*/*[@role='es20']/*)" />
</row>
<row >
<entry > <function > glTexParameteriv</function> </entry>
<xi:include xmlns:xi= "http://www.w3.org/2001/XInclude" href= "apiversion.xml" xpointer= "xpointer(/*/*[@role='es20']/*)" />
</row>
</tbody>
</tgroup>
</informaltable>
</refsect1>
<refsect1 xml:id= "seealso" > <title > See Also</title>
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<para >
<citerefentry > <refentrytitle > glActiveTexture</refentrytitle> </citerefentry> ,
<citerefentry > <refentrytitle > glBindTexture</refentrytitle> </citerefentry> ,
<citerefentry > <refentrytitle > glCopyTexImage2D</refentrytitle> </citerefentry> ,
<citerefentry > <refentrytitle > glCopyTexSubImage2D</refentrytitle> </citerefentry> ,
<citerefentry > <refentrytitle > glCopyTexSubImage3D</refentrytitle> </citerefentry> ,
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<citerefentry > <refentrytitle > glPixelStorei</refentrytitle> </citerefentry> ,
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<citerefentry > <refentrytitle > glSamplerParameter</refentrytitle> </citerefentry> ,
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<citerefentry > <refentrytitle > glTexStorage2D</refentrytitle> </citerefentry> ,
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<citerefentry > <refentrytitle > glTexImage2D</refentrytitle> </citerefentry> ,
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<citerefentry > <refentrytitle > glTexStorage3D</refentrytitle> </citerefentry> ,
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<citerefentry > <refentrytitle > glTexImage3D</refentrytitle> </citerefentry> ,
<citerefentry > <refentrytitle > glTexSubImage2D</refentrytitle> </citerefentry> ,
<citerefentry > <refentrytitle > glTexSubImage3D</refentrytitle> </citerefentry>
</para>
</refsect1>
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<refsect1 xml:id= "Copyright" > <title > Copyright</title>
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<para >
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Copyright <trademark class= "copyright" /> 1991-2006 Silicon Graphics, Inc.
Copyright <trademark class= "copyright" /> 2010-2014 Khronos Group.
This document is licensed under the SGI Free Software B License.
For details, see
<link xmlns:xlink= "http://www.w3.org/1999/xlink" xlink:href= "http://oss.sgi.com/projects/FreeB/" > http://oss.sgi.com/projects/FreeB/</link> .
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</para>
</refsect1>
</refentry>
