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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>glDrawRangeElements</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1" /></head><body><div class="refentry"><a id="glDrawRangeElements"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glDrawRangeElements — render primitives from array data</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">glDrawRangeElements</strong>(</code></td><td>GLenum <var class="pdparam">mode</var>, </td></tr><tr><td> </td><td>GLuint <var class="pdparam">start</var>, </td></tr><tr><td> </td><td>GLuint <var class="pdparam">end</var>, </td></tr><tr><td> </td><td>GLsizei <var class="pdparam">count</var>, </td></tr><tr><td> </td><td>GLenum <var class="pdparam">type</var>, </td></tr><tr><td> </td><td>const GLvoid * <var class="pdparam">indices</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>mode</code></em></span></dt><dd><p>
                    Specifies what kind of primitives to render.
                    Symbolic constants
                    <code class="constant">GL_POINTS</code>,
                    <code class="constant">GL_LINE_STRIP</code>,
                    <code class="constant">GL_LINE_LOOP</code>,
                    <code class="constant">GL_LINES</code>,
                    <code class="constant">GL_TRIANGLE_STRIP</code>,
                    <code class="constant">GL_TRIANGLE_FAN</code>,
                    <code class="constant">GL_TRIANGLES</code>,
                    <code class="constant">GL_QUAD_STRIP</code>,
                    <code class="constant">GL_QUADS</code>,
                    and <code class="constant">GL_POLYGON</code> are accepted.
                </p></dd><dt><span class="term"><em class="parameter"><code>start</code></em></span></dt><dd><p>
                    Specifies the minimum array index contained in <em class="parameter"><code>indices</code></em>.
                </p></dd><dt><span class="term"><em class="parameter"><code>end</code></em></span></dt><dd><p>
                    Specifies the maximum array index contained in <em class="parameter"><code>indices</code></em>.
                </p></dd><dt><span class="term"><em class="parameter"><code>count</code></em></span></dt><dd><p>
                    Specifies the number of elements to be rendered.
                </p></dd><dt><span class="term"><em class="parameter"><code>type</code></em></span></dt><dd><p>
                    Specifies the type of the values in <em class="parameter"><code>indices</code></em>. Must be one of
                    <code class="constant">GL_UNSIGNED_BYTE</code>, <code class="constant">GL_UNSIGNED_SHORT</code>, or
                    <code class="constant">GL_UNSIGNED_INT</code>.
                </p></dd><dt><span class="term"><em class="parameter"><code>indices</code></em></span></dt><dd><p>
                    Specifies a pointer to the location where the indices are stored.
                </p></dd></dl></div></div><div class="refsect1"><a id="description"></a><h2>Description</h2><p>
            <code class="function">glDrawRangeElements</code> is a restricted form of <a class="citerefentry" href="glDrawElements.xml"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>. <em class="parameter"><code>mode</code></em>
            and <em class="parameter"><code>count</code></em> match the corresponding arguments to <a class="citerefentry" href="glDrawElements.xml"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>, with
            the additional constraint that all values in the arrays <em class="parameter"><code>count</code></em> must lie
            between <em class="parameter"><code>start</code></em> and <em class="parameter"><code>end</code></em>, inclusive.
        </p><p>
            Implementations denote recommended maximum amounts of vertex and
            index data,
            which may be queried by calling <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument
            <code class="constant">GL_MAX_ELEMENTS_VERTICES</code> and <code class="constant">GL_MAX_ELEMENTS_INDICES</code>.
            If 
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                    <mml:mo>+</mml:mo>
                    <mml:mn>1</mml:mn>
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            is greater than the value of
            <code class="constant">GL_MAX_ELEMENTS_VERTICES</code>, or if <em class="parameter"><code>count</code></em> is greater than the value of
            <code class="constant">GL_MAX_ELEMENTS_INDICES</code>, then the call may operate at reduced
            performance.  There is no requirement that all vertices in the range
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            be referenced.  However, the implementation may
            partially process unused vertices, reducing performance from what could
            be achieved with an optimal index set.
        </p><p>
            When <code class="function">glDrawRangeElements</code> is called, it uses <em class="parameter"><code>count</code></em> sequential elements from an
            enabled array, starting at <em class="parameter"><code>start</code></em> to construct a sequence of
            geometric primitives. <em class="parameter"><code>mode</code></em> specifies what kind of primitives are
            constructed, and how the array elements construct these primitives. If
            more than one array is enabled, each is used. If
            <code class="constant">GL_VERTEX_ARRAY</code> is not enabled, no geometric primitives are
            constructed.
        </p><p>
            Vertex attributes that are modified by <code class="function">glDrawRangeElements</code> have an
            unspecified value after <code class="function">glDrawRangeElements</code> returns. For example, if
            <code class="constant">GL_COLOR_ARRAY</code> is enabled, the value of the current color is
            undefined after <code class="function">glDrawRangeElements</code> executes. Attributes that aren't
            modified maintain their previous values.
        </p></div><div class="refsect1"><a id="notes"></a><h2>Notes</h2><p>
            <code class="function">glDrawRangeElements</code> is available only if the GL version is 1.2 or greater.
        </p><p>
            <code class="function">glDrawRangeElements</code> is included in display lists. If <code class="function">glDrawRangeElements</code> is entered into a
            display list,
            the necessary array data (determined by the array pointers and
            enables) is also
            entered into the display list. Because the array pointers and
            enables are client-side state, their values affect display lists
            when the lists are created, not when the lists are executed.
        </p></div><div class="refsect1"><a id="errors"></a><h2>Errors</h2><p>
            It is an error for indices to lie outside the range 
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            but implementations may not check for this situation. Such indices
            cause implementation-dependent behavior.
        </p><p>
            <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>mode</code></em> is not an accepted value.
        </p><p>
            <code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>count</code></em> is negative.
        </p><p>
            <code class="constant">GL_INVALID_VALUE</code> is generated if 
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            </mml:math>.
        </p><p>
            <code class="constant">GL_INVALID_OPERATION</code> is generated if a non-zero buffer object name is bound to an
            enabled array or the element array and the buffer object's data store is currently mapped.
        </p><p>
            <code class="constant">GL_INVALID_OPERATION</code> is generated if <code class="function">glDrawRangeElements</code> is executed between
            the execution of <a class="citerefentry" href="glBegin.xml"><span class="citerefentry"><span class="refentrytitle">glBegin</span></span></a> and the corresponding <a class="citerefentry" href="glEnd.xml"><span class="citerefentry"><span class="refentrytitle">glEnd</span></span></a>.
        </p></div><div class="refsect1"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MAX_ELEMENTS_VERTICES</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MAX_ELEMENTS_INDICES</code>
        </p></div><div class="refsect1"><a id="seealso"></a><h2>See Also</h2><p>
            <a class="citerefentry" href="glArrayElement.xml"><span class="citerefentry"><span class="refentrytitle">glArrayElement</span></span></a>,
            <a class="citerefentry" href="glColorPointer.xml"><span class="citerefentry"><span class="refentrytitle">glColorPointer</span></span></a>,
            <a class="citerefentry" href="glDrawArrays.xml"><span class="citerefentry"><span class="refentrytitle">glDrawArrays</span></span></a>,
            <a class="citerefentry" href="glDrawElements.xml"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>,
            <a class="citerefentry" href="glEdgeFlagPointer.xml"><span class="citerefentry"><span class="refentrytitle">glEdgeFlagPointer</span></span></a>,
            <a class="citerefentry" href="glGetPointerv.xml"><span class="citerefentry"><span class="refentrytitle">glGetPointerv</span></span></a>,
            <a class="citerefentry" href="glIndexPointer.xml"><span class="citerefentry"><span class="refentrytitle">glIndexPointer</span></span></a>,
            <a class="citerefentry" href="glInterleavedArrays.xml"><span class="citerefentry"><span class="refentrytitle">glInterleavedArrays</span></span></a>,
            <a class="citerefentry" href="glNormalPointer.xml"><span class="citerefentry"><span class="refentrytitle">glNormalPointer</span></span></a>,
            <a class="citerefentry" href="glSecondaryColorPointer.xml"><span class="citerefentry"><span class="refentrytitle">glSecondaryColorPointer</span></span></a>,
            <a class="citerefentry" href="glTexCoordPointer.xml"><span class="citerefentry"><span class="refentrytitle">glTexCoordPointer</span></span></a>,
            <a class="citerefentry" href="glVertexPointer.xml"><span class="citerefentry"><span class="refentrytitle">glVertexPointer</span></span></a>
        </p></div><div class="refsect1"><a id="Copyright"></a><h2>Copyright</h2><p>
            Copyright <span class="trademark"></span>© 1991-2006
            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>