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<?xml-stylesheet type="text/xsl" href="mathml.xsl"?><html xmlns="http://www.w3.org/1999/xhtml" xmlns:pref="http://www.w3.org/2002/Math/preference" pref:renderer="mathplayer-dl"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>glDepthRange</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1" /></head><body><div class="refentry"><a id="glDepthRange"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glDepthRange — specify mapping of depth values from normalized
        device coordinates to window coordinates</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">void <strong class="fsfunc">glDepthRangef</strong>(</code></td><td>GLclampf <var class="pdparam">near</var>, </td></tr><tr><td> </td><td>GLclampf <var class="pdparam">far</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">void <strong class="fsfunc">glDepthRangex</strong>(</code></td><td>GLclampx <var class="pdparam">near</var>, </td></tr><tr><td> </td><td>GLclampx <var class="pdparam">far</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term">
                    <em class="parameter"><code>near</code></em>
                </span></dt><dd><p>Specifies the mapping of the near clipping plane to
                    window coordinates. The initial value is 0.</p></dd><dt><span class="term">
                    <em class="parameter"><code>far</code></em>
                </span></dt><dd><p>Specifies the mapping of the far clipping plane to
                    window coordinates. The initial value is 1.</p></dd></dl></div></div><div class="refsect1"><a id="description"></a><h2>Description</h2><p>After clipping and division by <em class="parameter"><code>w</code></em>,
        depth coordinates range from -1 to 1, corresponding to the
        near and far clipping planes. <code class="function">glDepthRange</code>
        specifies a linear mapping of the normalized depth coordinates
        in this range to window depth coordinates. Regardless of the
        actual depth buffer implementation, window coordinate depth
        values are treated as though they range from 0 through 1 (like
        color components). Thus, the values accepted by
        <code class="function">glDepthRange</code>
        are both clamped to this range before they are accepted.</p><p>The setting of (0, 1) maps the near plane to 0 and the far
        plane to 1. With this mapping, the depth buffer range is fully
        utilized.</p></div><div class="refsect1"><a id="notes"></a><h2>Notes</h2><p>It is not necessary that <em class="parameter"><code>near</code></em>
        be less than <em class="parameter"><code>far</code></em>.
        Reverse mappings such as
        <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
            <mml:mi>near</mml:mi>
            <mml:mo>=</mml:mo>
            <mml:mn>1</mml:mn>
        </mml:math>,
        and
        <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
            <mml:mi>far</mml:mi>
            <mml:mo>=</mml:mo>
            <mml:mn>0</mml:mn>
        </mml:math>
        are acceptable.</p></div><div class="refsect1"><a id="seealso"></a><h2>See Also</h2><p>
        <a class="citerefentry" href="glDepthFunc.xml"><span class="citerefentry"><span class="refentrytitle">glDepthFunc</span></span></a>,
        <a class="citerefentry" href="glPolygonOffset.xml"><span class="citerefentry"><span class="refentrytitle">glPolygonOffset</span></span></a>,
        <a class="citerefentry" href="glViewport.xml"><span class="citerefentry"><span class="refentrytitle">glViewport</span></span></a>
        </p></div><div class="refsect1"><a id="copyright"></a><h2>Copyright</h2><p>
            Copyright <span class="trademark"></span>© 2003-2004
            Silicon Graphics, Inc. This document is licensed under the SGI
            Free Software B License. For details, see
            <a class="ulink" href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
        </p></div></div></body></html>