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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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<refentry id="glNormalPointer">
  <refmeta>
    <refentrytitle>glNormalPointer</refentrytitle>
    <manvolnum>3G</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>glNormalPointer</refname>
    <refpurpose>define an array of normals</refpurpose>
  </refnamediv>

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

    <funcsynopsis>
      <funcprototype>
        <funcdef>void <function>glNormalPointer</function></funcdef>
        <paramdef>GLenum <parameter>type</parameter></paramdef>
        <paramdef>GLsizei <parameter>stride</parameter></paramdef>
        <paramdef>const GLvoid * <parameter>pointer</parameter></paramdef>
      </funcprototype>
    </funcsynopsis>
  </refsynopsisdiv>

  <refsect1>
    <title>Parameters</title>

    <variablelist>
      <varlistentry>
        <term>
          <parameter>type</parameter>
        </term>

        <listitem>
          <para>Specifies the data type of each coordinate in the
          array. Symbolic constants 
          <constant>GL_BYTE</constant>, 
          <constant>GL_SHORT</constant>, and
          <constant>GL_FIXED</constant> are accepted.
          However, the initial value is 
          <constant>GL_FLOAT</constant>.</para>

          <para>
            The common profile accepts the symbolic constant
            <constant>GL_FLOAT</constant> as well.
          </para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <parameter>stride</parameter>
        </term>

        <listitem>
          <para>Specifies the byte offset between consecutive
          normals. If <parameter>stride</parameter>
          is 0, the normals are understood to be
          tightly packed in the array. The initial value is
          0.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <parameter>pointer</parameter>
        </term>

        <listitem>
          <para>Specifies a pointer to the first coordinate of the
          first normal in the array. The initial value is 0.</para>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>Description</title>

    <para><function>glNormalPointer</function>
    specifies the location and data of an array of normals to use
    when rendering.  <parameter>type</parameter>
    specifies the data type of the normal coordinates and 
    <parameter>stride</parameter>
    gives the byte stride from one normal to the next, allowing
    vertices and attributes to be packed into a single array or
    stored in separate arrays. (Single-array storage may be more
    efficient on some implementations.) When a normal array is
    specified, 
    <parameter>type</parameter> , 
    <parameter>stride</parameter> , and 
    <parameter>pointer</parameter> 
    are saved as client-side state.</para>

    <para>
    If the normal array is enabled, it is used when 
    <citerefentry><refentrytitle>glDrawArrays</refentrytitle></citerefentry> or
    <citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry> 
    is called.
    To enable and disable the normal array, call 
    <citerefentry><refentrytitle>glEnableClientState</refentrytitle></citerefentry>
    and 
    <citerefentry><refentrytitle>glDisableClientState</refentrytitle></citerefentry>
    with the argument <constant>GL_NORMAL_ARRAY</constant>.
    The normal array is initially disabled and isn't accessed when 
    <citerefentry><refentrytitle>glDrawArrays</refentrytitle></citerefentry> or
    <citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry>
    is called.</para>

    <para>Use 
    <citerefentry><refentrytitle>glDrawArrays</refentrytitle></citerefentry>
    to construct a sequence of primitives (all of the same type)
    from prespecified vertex and vertex attribute arrays. Use
    <citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry>
    to construct a sequence of primitives by indexing vertices and
    vertex attributes.</para>
  </refsect1>

  <refsect1>
    <title>Notes</title>

    <para><function>glNormalPointer</function>
    is typically implemented on the client side.</para>
  </refsect1>

  <refsect1>
    <title>Errors</title>

    <para><constant>GL_INVALID_ENUM</constant> is generated if 
    <parameter>type</parameter> is not an accepted value.</para>

    <para><constant>GL_INVALID_VALUE</constant> is generated if 
    <parameter>stride</parameter> is negative.</para>
  </refsect1>

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

    <para>
    <citerefentry><refentrytitle>glColorPointer</refentrytitle></citerefentry>, 
    <citerefentry><refentrytitle>glDrawArrays</refentrytitle></citerefentry>, 
    <citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry>, 
    <citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry>, 
    <citerefentry><refentrytitle>glTexCoordPointer</refentrytitle></citerefentry>, 
    <citerefentry><refentrytitle>glVertexPointer</refentrytitle></citerefentry>
    </para>
  </refsect1>
</refentry>