Opentk/Source/Bind/Specifications/Docs/glGenerateMipmap.xml
2010-11-21 14:34:29 +00:00

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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
"http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
<refentry id="glGenerateMipmap">
<refmeta>
<refmetainfo>
<copyright>
<year>2010</year>
<holder>Khronos Group</holder>
</copyright>
</refmetainfo>
<refentrytitle>glGenerateMipmap</refentrytitle>
<manvolnum>3G</manvolnum>
</refmeta>
<refnamediv>
<refname>glGenerateMipmap</refname>
<refpurpose>generate mipmaps for a specified texture target</refpurpose>
</refnamediv>
<refsynopsisdiv><title>C Specification</title>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>glGenerateMipmap</function></funcdef>
<paramdef>GLenum <parameter>target</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<!-- eqn: ignoring delim $$ -->
<refsect1 id="parameters"><title>Parameters</title>
<variablelist>
<varlistentry>
<term><parameter>target</parameter></term>
<listitem>
<para>
Specifies the target to which the texture whose mimaps to generate is bound. <parameter>target</parameter> must
be <constant>GL_TEXTURE_1D</constant>, <constant>GL_TEXTURE_2D</constant>, <constant>GL_TEXTURE_3D</constant>,
<constant>GL_TEXTURE_1D_ARRAY</constant>, <constant>GL_TEXTURE_2D_ARRAY</constant> or
<constant>GL_TEXTURE_CUBE_MAP</constant>.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 id="description"><title>Description</title>
<para>
<function>glGenerateMipmap</function> generates mipmaps for the texture attached
to <parameter>target</parameter> of the active texture unit. For cube map textures,
a <constant>GL_INVALID_OPERATION</constant> error is generated if the texture
attached to <parameter>target</parameter> is not cube complete.
</para>
<para>
Mipmap generation replaces texel array levels
<inlineequation><mml:math>
<!-- eqn: level sub base + 1: -->
<mml:mrow>
<mml:msub>
<mml:mi mathvariant="italic">level</mml:mi>
<mml:mi>base</mml:mi>
</mml:msub>
<mml:mo>+</mml:mo>
<mml:mn>1</mml:mn>
</mml:mrow>
</mml:math></inlineequation>
through
<inlineequation><mml:math>
<mml:mrow>
<mml:mi mathvariant="italic">q</mml:mi>
</mml:mrow>
</mml:math></inlineequation>
with arrays derived from the
<inlineequation><mml:math>
<!-- eqn: level sub base + 1: -->
<mml:mrow>
<mml:msub>
<mml:mi mathvariant="italic">level</mml:mi>
<mml:mi>base</mml:mi>
</mml:msub>
</mml:mrow>
</mml:math></inlineequation>
array, regardless of their previous contents. All other mimap arrays,
including the
<inlineequation><mml:math>
<!-- eqn: level sub base + 1: -->
<mml:mrow>
<mml:msub>
<mml:mi mathvariant="italic">level</mml:mi>
<mml:mi>base</mml:mi>
</mml:msub>
</mml:mrow>
</mml:math></inlineequation>
array, are left unchanged by this computation.
</para>
<para>
The internal formats of the derived mipmap arrays all match those of the
<inlineequation><mml:math>
<!-- eqn: level sub base + 1: -->
<mml:mrow>
<mml:msub>
<mml:mi mathvariant="italic">level</mml:mi>
<mml:mi>base</mml:mi>
</mml:msub>
</mml:mrow>
</mml:math></inlineequation>
array. The contents of the derived arrays are computed by repeated, filtered
reduction of the
<inlineequation><mml:math>
<!-- eqn: level sub base + 1: -->
<mml:mrow>
<mml:msub>
<mml:mi mathvariant="italic">level</mml:mi>
<mml:mi>base</mml:mi>
</mml:msub>
</mml:mrow>
</mml:math></inlineequation>
array. For one- and two-dimensional texture arrays, each layer is filtered
independently.
</para>
</refsect1>
<refsect1 id="errors"><title>Errors</title>
<para>
<constant>GL_INVALID_ENUM</constant> is generated if <parameter>target</parameter> is not
one of the accepted texture targets.
</para>
<para>
<constant>GL_INVALID_OPERATION</constant> is generated if <parameter>target</parameter> is
<constant>GL_TEXTURE_CUBE_MAP</constant> and the texture bound to the <constant>GL_TEXTURE_CUBE_MAP</constant>
target of the active texture unit is not cube complete.
</para>
</refsect1>
<refsect1 id="seealso"><title>See Also</title>
<para>
<citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glBindTexture</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glGenTextures</refentrytitle></citerefentry>
</para>
</refsect1>
<refsect1 id="Copyright"><title>Copyright</title>
<para>
Copyright <trademark class="copyright"></trademark> 2010 Khronos Group.
This material may be distributed subject to the terms and conditions set forth in
the Open Publication License, v 1.0, 8 June 1999.
<ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
</para>
</refsect1>
</refentry>