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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="glQueryMatrix">
  <refmeta>
    <refentrytitle>glQueryMatrix</refentrytitle>
    <manvolnum>3G</manvolnum>
  </refmeta>

  <refnamediv>
    <refdescriptor>glQueryMatrix</refdescriptor>
    <refname>glQueryMatrixxOES</refname>
    <refpurpose>return the values of the current matrix</refpurpose>
  </refnamediv>

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

    <funcsynopsis>
      <funcprototype>
        <funcdef>GLbitfield <function>glQueryMatrixxOES</function></funcdef>
        <paramdef>GLfixed * <parameter>mantissa</parameter></paramdef>
        <paramdef>GLint * <parameter>exponent</parameter></paramdef>
      </funcprototype>
    </funcsynopsis>
  </refsynopsisdiv>

  <refsect1>
    <title>Parameters</title>

    <variablelist>
      <varlistentry>
        <term>
          <parameter>mantissa</parameter>
        </term>

        <listitem>
          <para>Returns the mantissi of the current matrix.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <parameter>exponent</parameter>
        </term>

        <listitem>
          <para>Returns the exponents of the current matrix.</para>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>Description</title>

    <para><function>glQueryMatrixxOES</function>
    returns the values of the current matrix.
    <parameter>mantissa</parameter> returns the 16 mantissa values
    of the current matrix, and <parameter>exponent</parameter> returns
    the correspnding 16 exponent values.
    The matrix value <replaceable>i</replaceable> is then close to
    <inlineequation><math>
      <mi>mantissa</mi><mo>[</mo><mi>i</mi><mo>]</mo><mo>*</mo>
      <msup><mn>2</mn><mrow><mi>exponent</mi><mo>[</mo><mi>i</mi><mo>]</mo></mrow></msup>
    </math></inlineequation>.</para>

    <para>Use 
    <citerefentry><refentrytitle>glMatrixMode</refentrytitle></citerefentry> and
    <citerefentry><refentrytitle>glActiveTexture</refentrytitle></citerefentry>,
    to select the desired matrix to return.</para>

    <para>If all are valid (not NaN or Inf),
    <function>glQueryMatrixxOES</function> returns the status value 0.
    Otherwise, for every component <replaceable>i</replaceable> which is
    not valid, the <replaceable>i</replaceable>th bit is set.</para>
  </refsect1>

  <refsect1>
    <title>Notes</title>

    <para><function>glQueryMatrixxOES</function> is available only if
    the <constant>GL_OES_query_matrix</constant> extension is supported
    by your implementation.</para>

    <para>The implementation is not required to keep track of overflows.
    If overflows are not tracked, the returned status value is always
    0.</para>
  </refsect1>

  <refsect1>
    <title>Associated Gets</title>

    <para><citerefentry><refentrytitle>glGetString</refentrytitle></citerefentry>
    with argument <constant>GL_EXTENSIONS</constant></para>
  </refsect1>

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

    <para>
      <citerefentry><refentrytitle>glActiveTexture</refentrytitle></citerefentry>,
      <citerefentry><refentrytitle>glGetString</refentrytitle></citerefentry>,
      <citerefentry><refentrytitle>glMatrixMode</refentrytitle></citerefentry>
    </para>
  </refsect1>
</refentry>