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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="unpackUnorm">
<info>
<copyright>
<year>2011-2014</year>
<holder>Khronos Group</holder>
</copyright>
</info>
<refmeta>
<refentrytitle>unpackUnorm</refentrytitle>
<manvolnum>3G</manvolnum>
</refmeta>
<refnamediv>
<refname>unpackUnorm2x16, unpackUnorm4x8, unpackSnorm4x8</refname>
<refpurpose>unpack floating-point values from an unsigned integer</refpurpose>
</refnamediv>
<refsynopsisdiv><title>Declaration</title>
<funcsynopsis>
<funcprototype>
<funcdef>vec2 <function>unpackUnorm2x16</function></funcdef>
<paramdef>uint <parameter>p</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>vec2 <function>unpackSnorm2x16</function></funcdef>
<paramdef>uint <parameter>p</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>vec4 <function>unpackUnorm4x8</function></funcdef>
<paramdef>uint <parameter>p</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>vec4 <function>unpackSnorm4x8</function></funcdef>
<paramdef>uint <parameter>p</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1 xml:id="parameters"><title>Parameters</title>
<variablelist>
<varlistentry>
<term><parameter>p</parameter></term>
<listitem>
<para>
Specifies an unsigned integer containing packed floating-point values.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 xml:id="description"><title>Description</title>
<para>
<function>unpackUnorm2x16</function>, <function>unpackSnorm2x16</function>, <function>unpackUnorm4x8</function> and <function>unpackSnorm4x8</function> unpack
single 32-bit unsigned integers, specified in the parameter <parameter>p</parameter> into a pair of 16-bit unsigned integers,
four 8-bit unsigned integers or four 8-bit signed integers. Then, each component is converted to a normalized floating-point
value to generate the returned two- or four-component vector.
</para>
<para>
The conversion for unpacked fixed point value <emphasis>f</emphasis> to floating-point is performed as follows:
<itemizedlist>
<listitem><para><function>packUnorm2x16</function>: <code>f / 65535.0</code></para></listitem>
<listitem><para><function>packSnorm2x16</function>: <code><function>clamp</function>(f / 32727.0, -1.0, 1.0)</code></para></listitem>
<listitem><para><function>packUnorm4x8</function>: <code>f / 255.0</code></para></listitem>
<listitem><para><function>packSnorm4x8</function>: <code><function>clamp</function>(f / 127.0, -1.0, 1.0)</code></para></listitem>
</itemizedlist>
</para>
<para>
The first component of the returned vector will be extracted from the least significant bits of the input;
the last component will be extracted from the most significant bits.
</para>
</refsect1>
<refsect1 xml:id="versions"><title>Version Support</title>
<informaltable>
<tgroup cols="13" align="left">
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="funchead.xml" xpointer="xpointer(/*/*)"/>
<tbody>
<row>
<entry>unpackUnorm2x16</entry>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="version.xml" xpointer="xpointer(/*/*[@role='41']/*)"/>
</row>
<row>
<entry>unpackSnorm2x16</entry>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="version.xml" xpointer="xpointer(/*/*[@role='42']/*)"/>
</row>
<row>
<entry>unpackUnorm4x8</entry>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="version.xml" xpointer="xpointer(/*/*[@role='41']/*)"/>
</row>
<row>
<entry>unpackSnorm4x8</entry>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="version.xml" xpointer="xpointer(/*/*[@role='41']/*)"/>
</row>
</tbody>
</tgroup>
</informaltable>
</refsect1>
<refsect1 xml:id="seealso"><title>See Also</title>
<para>
<!-- FIX: link to packUnorm --> <function>packUnorm2x16</function>,
<!-- FIX: link to packUnorm --> <function>packUnorm4x8</function>,
<!-- FIX: link to packUnorm --> <function>packSnorm4x8</function>
</para>
</refsect1>
<refsect1 xml:id="Copyright"><title>Copyright</title>
<para>
Copyright <trademark class="copyright"/> 2011-2014 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.
<link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://opencontent.org/openpub/">http://opencontent.org/openpub/</link>.
</para>
</refsect1>
</refentry>
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