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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" /><link rel="stylesheet" type="text/css" href="opengl-man.css" /><title>glDepthRangeArray - OpenGL 4 Reference Pages</title><meta name="generator" content="DocBook XSL Stylesheets V1.69.1" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="glDepthRangeArray"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glDepthRangeArray — specify mapping of depth values from normalized device coordinates to window coordinates for a specified set of viewports</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glDepthRangeArrayv</b>(</code></td><td>GLuint  </td><td><var class="pdparam">first</var>, </td></tr><tr><td> </td><td>GLsizei  </td><td><var class="pdparam">count</var>, </td></tr><tr><td> </td><td>const GLdouble * </td><td><var class="pdparam">v</var><code>)</code>;</td></tr></table></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>first</code></em></span></dt><dd><p>
                    Specifies the index of the first viewport whose depth range to update.
                </p></dd><dt><span class="term"><em class="parameter"><code>count</code></em></span></dt><dd><p>
                    Specifies the number of viewports whose depth range to update.
                </p></dd><dt><span class="term"><em class="parameter"><code>v</code></em></span></dt><dd><p>
                    Specifies the address of an array containing the near and far values for the
                    depth range of each modified viewport.
                </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
            After clipping and division by <span class="emphasis"><em>w</em></span>,
            depth coordinates range from 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mn>-1</mml:mn>
            </mml:math>
            to 1,
            corresponding to the near and far clipping planes.
            Each viewport has an independent depth range specified as 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).
            <code class="function">glDepthRangeArray</code> specifies a linear mapping of the normalized depth coordinates
            in this range to window depth coordinates for each viewport in the range [<em class="parameter"><code>first</code></em>,
            <em class="parameter"><code>first</code></em> + <em class="parameter"><code>count</code></em>).
            Thus,
            the values accepted by <code class="function">glDepthRangeArray</code> are both clamped to this range
            before they are accepted.
        </p><p>
            The <em class="parameter"><code>first</code></em> parameter specifies the index of the first viewport whose depth
            range to modify and must be less than the value of <code class="constant">GL_MAX_VIEWPORTS</code>.
            <em class="parameter"><code>count</code></em> specifies the number of viewports whose depth range to modify.
            <em class="parameter"><code>first</code></em> + <em class="parameter"><code>count</code></em> must be less than or equal to
            the value of <code class="constant">GL_MAX_VIEWPORTS</code>. <em class="parameter"><code>v</code></em> specifies the address of an
            array of pairs of double precision floating point values representing the near and far values of the
            depth range for each viewport, in that order.
        </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" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
            It is not necessary that the near plane distance be less than the far plane distance.
            Reverse mappings such as 
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                <mml:mrow>
                    <mml:mi mathvariant="italic">near</mml:mi>
                    <mml:mo>=</mml:mo>
                    <mml:mn>1</mml:mn>
                </mml:mrow>
            </mml:math>,
            and 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mrow>
                    <mml:mi mathvariant="italic">far</mml:mi>
                    <mml:mo>=</mml:mo>
                    <mml:mn>0</mml:mn>
                </mml:mrow>
            </mml:math>
            are acceptable.
        </p><p>
            The type of the <em class="parameter"><code>v</code></em> parameter was
            changed from GLclampd to GLdouble. This change is
            transparent to user code and is described in detail on the
            <a href="removedTypes.xml"><span class="citerefentry"><span class="refentrytitle">removedTypes</span></span></a>
            page.
        </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
            <code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>first</code></em> is greater than or equal to
            the value of <code class="constant">GL_MAX_VIEWPORTS</code>.
        </p><p>
            <code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>first</code></em> + <em class="parameter"><code>count</code></em>
            is greater than or equal to the value of <code class="constant">GL_MAX_VIEWPORTS</code>.
        </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
            <a href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_DEPTH_RANGE</code>
        </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
            <a href="glDepthFunc.xml"><span class="citerefentry"><span class="refentrytitle">glDepthFunc</span></span></a>,
            <a href="glDepthRange.xml"><span class="citerefentry"><span class="refentrytitle">glDepthRange</span></span></a>,
            <a href="glDepthRangeIndexed.xml"><span class="citerefentry"><span class="refentrytitle">glDepthRangeIndexed</span></span></a>,
            <a href="glPolygonOffset.xml"><span class="citerefentry"><span class="refentrytitle">glPolygonOffset</span></span></a>,
            <a href="glViewportArray.xml"><span class="citerefentry"><span class="refentrytitle">glViewportArray</span></span></a>,
            <a href="glViewport.xml"><span class="citerefentry"><span class="refentrytitle">glViewport</span></span></a>,
            <a href="removedTypes.xml"><span class="citerefentry"><span class="refentrytitle">removedTypes</span></span></a>
        </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
            Copyright <span class="trademark"></span>© 2010 Khronos Group. 
            This material may be distributed subject to the terms and conditions set forth in 
            the Open Publication License, v 1.0, 8 June 1999.
            <a href="http://opencontent.org/openpub/" target="_top">http://opencontent.org/openpub/</a>.
        </p></div></div></body></html>
