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OpenGL ES 1.0 and EGL 1.0 reference manual and man pages (written by
Claude Knaus, based on OpenGL SI man pages).

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V4.2//EN" "DTD/docbook/docbookx.dtd">

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  Original Code. The Original Code is: OpenGL ES Reference Manual,
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<refentry id="glNormal">
  <refmeta>
    <refentrytitle>glNormal</refentrytitle>
    <manvolnum>3G</manvolnum>
  </refmeta>

  <refnamediv>
    <refdescriptor>glNormal</refdescriptor>
    <refname>glNormal3f</refname>
    <refname>glNormal3x</refname>
    <refpurpose>set the current normal vector</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <title>C Specification</title>

    <funcsynopsis>
      <funcprototype>
        <funcdef>void <function>glNormal3f</function></funcdef>
        <paramdef>GLfloat <parameter>nx</parameter></paramdef>
        <paramdef>GLfloat <parameter>ny</parameter></paramdef>
        <paramdef>GLfloat <parameter>nz</parameter></paramdef>
      </funcprototype>
      <funcprototype>
        <funcdef>void <function>glNormal3x</function></funcdef>
        <paramdef>GLfixed <parameter>nx</parameter></paramdef>
        <paramdef>GLfixed <parameter>ny</parameter></paramdef>
        <paramdef>GLfixed <parameter>nz</parameter></paramdef>
      </funcprototype>
    </funcsynopsis>
  </refsynopsisdiv>

  <refsect1>
    <title>Parameters</title>

    <variablelist>
      <varlistentry>
        <term>
        <parameter>nx</parameter>, 
        <parameter>ny</parameter>,
        <parameter>nz</parameter>
        </term>

        <listitem>
          <para>Specify the
          <parameter>x</parameter>,
          <parameter>y</parameter>, and
          <parameter>z</parameter> coordinates of the
          new current normal. The initial value is (0, 0, 1).</para>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>Description</title>

    <para>The current normal is set to the given coordinates whenever 
    <function>glNormal</function>
    is issued. Byte, short, or integer arguments are converted to
    floating-point with a linear mapping that maps the most
    positive representable integer value to 1.0, and the most
    negative representable integer value to -1.0.</para>

    <para>Normals specified with <function>glNormal</function>
    need not have unit length. If <constant>GL_NORMALIZE</constant>
    is enabled, then normals of any length specified with 
    <function>glNormal</function>
    are normalized after transformation. If 
    <constant>GL_RESCALE_NORMAL</constant>
    is enabled, normals are scaled by a scaling factor derived from
    the modelview matrix.  <constant>GL_RESCALE_NORMAL</constant>
    requires that the originally specified normals were of unit
    length, and that the modelview matrix contain only uniform
    scales for proper results. To enable and disable normalization,
    call 
    <citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry> and 
    <citerefentry><refentrytitle>glDisable</refentrytitle></citerefentry>
    with either 
    <constant>GL_NORMALIZE</constant> or <constant>GL_RESCALE_NORMAL</constant>.
    Normalization is initially disabled.</para>
  </refsect1>

<!--
  <refsect1>
    <title>Notes</title>

    <para>The current normal can be updated at any time.</para>
  </refsect1>
-->

  <refsect1>
    <title>See Also</title>

    <para>
    <citerefentry><refentrytitle>glColor</refentrytitle></citerefentry>, 
    <citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry>, 
    <citerefentry><refentrytitle>glMultiTexCoord</refentrytitle></citerefentry>,
    <citerefentry><refentrytitle>glNormalPointer</refentrytitle></citerefentry> 
    </para>
  </refsect1>
</refentry>