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

  <refnamediv>
    <refdescriptor>glScale</refdescriptor>
    <refname>glScalef</refname>
    <refname>glScalex</refname>
    <refpurpose>multiply the current matrix by a general scaling
    matrix</refpurpose>
  </refnamediv>

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

    <funcsynopsis>
      <funcprototype>
        <funcdef>void <function>glScalef</function></funcdef>
        <paramdef>GLfloat <parameter>x</parameter></paramdef>
        <paramdef>GLfloat <parameter>y</parameter></paramdef>
        <paramdef>GLfloat <parameter>z</parameter></paramdef>
      </funcprototype>
      <funcprototype>
        <funcdef>void <function>glScalex</function></funcdef>
        <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>x</parameter>, 
        <parameter>y</parameter>, 
        <parameter>z</parameter>
        </term>

        <listitem>
          <para>Specify scale factors along the 
          <parameter>x</parameter>, 
          <parameter>y</parameter>, and 
          <parameter>z</parameter> axes, respectively.</para>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>Description</title>

    <para>
    <function>glScale</function> produces a nonuniform scaling along the 
    <parameter>x</parameter>, 
    <parameter>y</parameter>, and 
    <parameter>z</parameter> 
    axes. The three parameters indicate the desired scale factor
    along each of the three axes.</para>

    <para>The current matrix (see 
    <citerefentry><refentrytitle>glMatrixMode</refentrytitle></citerefentry>)
    is multiplied by this scale matrix, and the product replaces
    the current matrix as if <function>glScale</function>
    were called with the following matrix as its argument:</para>

    <informalequation><math>
      <mrow>
        <mo>(</mo>
        <mtable class="matrix">
          <mtr>
            <mtd><mi>x</mi></mtd>
            <mtd><mn>0</mn></mtd>
            <mtd><mn>0</mn></mtd>
            <mtd><mn>0</mn></mtd>
          </mtr>
          <mtr>
            <mtd><mn>0</mn></mtd>
            <mtd><mi>y</mi></mtd>
            <mtd><mn>0</mn></mtd>
            <mtd><mn>0</mn></mtd>
          </mtr>
          <mtr>
            <mtd><mn>0</mn></mtd>
            <mtd><mn>0</mn></mtd>
            <mtd><mi>z</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>If the matrix mode is either <constant>GL_MODELVIEW</constant> or 
    <constant>GL_PROJECTION</constant>, all objects drawn after 
    <function>glScale</function> is called are scaled.</para>

    <para>Use 
    <citerefentry><refentrytitle>glPushMatrix</refentrytitle></citerefentry>
    and 
    <citerefentry><refentrytitle>glPopMatrix</refentrytitle></citerefentry>
    to save and restore the unscaled coordinate system.</para>
  </refsect1>

  <refsect1>
    <title>Notes</title>

    <para>If scale factors other than 1 are applied to the
    modelview matrix and lighting is enabled, lighting often
    appears wrong. In that case, enable automatic normalization of
    normals by calling 
    <citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry>
    with the argument <constant>GL_NORMALIZE</constant>.</para>
  </refsect1>

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

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