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

  <refnamediv>
    <refdescriptor>glRotate</refdescriptor>
    <refname>glRotatef</refname>
    <refname>glRotatex</refname>
    <refpurpose>multiply the current matrix by a rotation matrix</refpurpose>
  </refnamediv>

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

    <funcsynopsis>
      <funcprototype>
        <funcdef>void <function>glRotatef</function></funcdef>
        <paramdef>GLfloat <parameter>angle</parameter></paramdef>
        <paramdef>GLfloat <parameter>x</parameter></paramdef>
        <paramdef>GLfloat <parameter>y</parameter></paramdef>
        <paramdef>GLfloat <parameter>z</parameter></paramdef>
      </funcprototype>
      <funcprototype>
        <funcdef>void <function>glRotatex</function></funcdef>
        <paramdef>GLfixed <parameter>angle</parameter></paramdef>
        <paramdef>GLfixed <parameter>x</parameter></paramdef>
        <paramdef>GLfixed <parameter>y</parameter></paramdef>
        <paramdef>GLfixed <parameter>z</parameter></paramdef>
      </funcprototype>
    </funcsynopsis>
  </refsynopsisdiv>

  <refsect1>
    <title>Parameters</title>

    <variablelist>
      <varlistentry>
        <term>
          <parameter>angle</parameter>
        </term>

        <listitem>
          <para>Specifies the angle of rotation, in degrees.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
        <parameter>x</parameter>, 
        <parameter>y</parameter>, 
        <parameter>z</parameter>
        </term>

        <listitem>
          <para>Specify the 
          <parameter>x</parameter>, 
          <parameter>y</parameter>, and 
          <parameter>z</parameter> 
          coordinates of a vector, respectively.</para>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>Description</title>

    <para><function>glRotate</function> produces a rotation of 
    <parameter>angle</parameter> degrees around the vector 
    <inlineequation><math>
      <mfenced><mi>x</mi><mi>y</mi><mi>z</mi></mfenced>
    </math></inlineequation>.
    The current matrix (see 
    <citerefentry><refentrytitle>glMatrixMode</refentrytitle></citerefentry>)
    is multiplied by a rotation matrix with the product replacing
    the current matrix, as if 
    <citerefentry><refentrytitle>glMultMatrix</refentrytitle></citerefentry>
    were called with the following matrix as its argument:</para>

    <informalequation><math>
      <mrow>
        <mo>(</mo>
        <mtable class="matrix">
          <mtr>
            <mtd>
              <msup><mi>x</mi><mn>2</mn></msup>
              <mo>(</mo><mn>1</mn><mo>-</mo><mi>c</mi><mo>)</mo>
              <mo>+</mo><mi>c</mi>
            </mtd>
            <mtd>
              <mi>x</mi><mn>y</mn>
              <mo>(</mo><mn>1</mn><mo>-</mo><mi>c</mi><mo>)</mo>
              <mo>-</mo><mi>z</mi><mi>s</mi>
            </mtd>
            <mtd>
              <mi>x</mi><mn>z</mn>
              <mo>(</mo><mn>1</mn><mo>-</mo><mi>c</mi><mo>)</mo>
              <mo>+</mo><mi>y</mi><mi>s</mi>
            </mtd>
            <mtd><mn>0</mn></mtd>
          </mtr>
          <mtr>
            <mtd>
              <mi>x</mi><mn>y</mn>
              <mo>(</mo><mn>1</mn><mo>-</mo><mi>c</mi><mo>)</mo>
              <mo>+</mo><mi>z</mi><mi>s</mi>
            </mtd>
            <mtd>
              <msup><mi>y</mi><mn>2</mn></msup>
              <mo>(</mo><mn>1</mn><mo>-</mo><mi>c</mi><mo>)</mo>
              <mo>+</mo><mi>c</mi>
            </mtd>
            <mtd>
              <mi>y</mi><mn>z</mn>
              <mo>(</mo><mn>1</mn><mo>-</mo><mi>c</mi><mo>)</mo>
              <mo>-</mo><mi>x</mi><mi>s</mi>
            </mtd>
            <mtd><mn>0</mn></mtd>
          </mtr>
          <mtr>
            <mtd>
              <mi>x</mi><mn>z</mn>
              <mo>(</mo><mn>1</mn><mo>-</mo><mi>c</mi><mo>)</mo>
              <mo>-</mo><mi>y</mi><mi>s</mi>
            </mtd>
            <mtd>
              <mi>y</mi><mn>z</mn>
              <mo>(</mo><mn>1</mn><mo>-</mo><mi>c</mi><mo>)</mo>
              <mo>+</mo><mi>x</mi><mi>s</mi>
            </mtd>
            <mtd>
              <msup><mi>z</mi><mn>2</mn></msup>
              <mo>(</mo><mn>1</mn><mo>-</mo><mi>c</mi><mo>)</mo>
              <mo>+</mo><mi>c</mi>
            </mtd>
            <mtd><mn>0</mn></mtd>
          </mtr>
          <mtr>
            <mtd><mn>0</mn></mtd>
            <mtd><mn>0</mn></mtd>
            <mtd><mn>0</mn></mtd>
            <mtd><mn>1</mn></mtd>
          </mtr>
        </mtable>
        <mo>)</mo>
      </mrow>
    </math></informalequation>

    <para>Where 
    <inlineequation><math>
      <mi>c</mi><mo>=</mo><mo>cos</mo><mfenced><mi>angle</mi></mfenced>
    </math></inlineequation>,
    <inlineequation><math>
      <mi>s</mi><mo>=</mo><mo>sin</mo><mfenced><mi>angle</mi></mfenced>
    </math></inlineequation>,
    and 
    <inlineequation><math>
      <mo>||</mo><mfenced><mi>x</mi><mi>y</mi><mi>z</mi></mfenced><mo>||</mo>
      <mo>=</mo><mn>1</mn>
    </math></inlineequation>,
    (if not, the GL will normalize this vector).</para>
    <para>If the matrix mode is either <constant>GL_MODELVIEW</constant> or 
    <constant>GL_PROJECTION</constant>, all objects drawn after 
    <function>glRotate</function> is called are rotated. Use 
    <citerefentry><refentrytitle>glPushMatrix</refentrytitle></citerefentry>
    and 
    <citerefentry><refentrytitle>glPopMatrix</refentrytitle></citerefentry>
    to save and restore the unrotated coordinate system.</para>
  </refsect1>

  <refsect1>
    <title>Notes</title>

    <para>This rotation follows the right-hand rule, so if the vector 
    <inlineequation><math>
      <mfenced><mi>x</mi><mi>y</mi><mi>z</mi></mfenced>
    </math></inlineequation>
    points toward the user, the rotation will be counterclockwise.</para>
  </refsect1>

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

    <para>
    <citerefentry><refentrytitle>glMatrixMode</refentrytitle></citerefentry>, 
    <citerefentry><refentrytitle>glMultMatrix</refentrytitle></citerefentry>, 
    <citerefentry><refentrytitle>glPushMatrix</refentrytitle></citerefentry>, 
    <citerefentry><refentrytitle>glScale</refentrytitle></citerefentry>, 
    <citerefentry><refentrytitle>glTranslate</refentrytitle></citerefentry>
    </para>
  </refsect1>
</refentry>