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glDrawRangeElements.xhtml
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glDrawRangeElements.xhtml
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<div class="refentry" id="glDrawRangeElements">
<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 style="border: 0; cellspacing: 0; cellpadding: 0;" class="funcprototype-table">
<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" id="parameters">
<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> and
<code class="constant">GL_TRIANGLES</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 byte offset (cast to a pointer type) into the buffer bound to <code class="constant">GL_ELEMENT_ARRAY_BUFFER</code>
to start reading indices from. If no buffer is bound, specifies a pointer to the location where the indices are stored.
</p>
</dd>
</dl>
</div>
</div>
<div class="refsect1" id="description">
<h2>Description</h2>
<p>
<code class="function">glDrawRangeElements</code> is a restricted form of <a class="citerefentry" href="glDrawElements"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>. <em class="parameter"><code>mode</code></em>, <em class="parameter"><code>count</code></em>,
and <em class="parameter"><code>type</code></em> match the corresponding arguments to <a class="citerefentry" href="glDrawElements"><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"><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
<math overflow="scroll">
<mrow>
<mi mathvariant="italic">end</mi>
<mo>-</mo>
<mi mathvariant="italic">start</mi>
<mo>+</mo>
<mn>1</mn>
</mrow>
</math>
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
<math overflow="scroll">
<mfenced open="[" close="]">
<mi mathvariant="italic">start</mi>
<mi mathvariant="italic">end</mi>
</mfenced>
</math>
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.
</p>
<p>
To enable and disable a generic vertex attribute array, call
<a class="citerefentry" href="glEnableVertexAttribArray"><span class="citerefentry"><span class="refentrytitle">glEnableVertexAttribArray</span></span></a> and
<a class="citerefentry" href="glDisableVertexAttribArray"><span class="citerefentry"><span class="refentrytitle">glDisableVertexAttribArray</span></span></a>.
</p>
<p>
If an array corresponding to a generic attribute required by a vertex shader
is not enabled, then the corresponding element is taken from the current generic
attribute state.
</p>
</div>
<div class="refsect1" id="errors">
<h2>Errors</h2>
<p>
It is an error for indices to lie outside the range
<math overflow="scroll">
<mfenced open="[" close="]">
<mi mathvariant="italic">start</mi>
<mi mathvariant="italic">end</mi>
</mfenced>
</math>,
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
<math overflow="scroll">
<mrow>
<mi mathvariant="italic">end</mi>
<mo><</mo>
<mi mathvariant="italic">start</mi>
</mrow>
</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_FRAMEBUFFER_OPERATION</code> is generated if the currently bound framebuffer is not
framebuffer complete (i.e. the return value from
<a class="citerefentry" href="glCheckFramebufferStatus"><span class="citerefentry"><span class="refentrytitle">glCheckFramebufferStatus</span></span></a> is not <code class="constant">GL_FRAMEBUFFER_COMPLETE</code>).
</p>
<p>
<code class="constant">GL_INVALID_OPERATION</code> is generated if transform feedback is active and not paused.
</p>
</div>
<div class="refsect1" id="associatedgets">
<h2>Associated Gets</h2>
<p>
<a class="citerefentry" href="glGet"><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"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MAX_ELEMENTS_INDICES</code>
</p>
</div>
{$pipelinestall}{$examples}
<div class="refsect1" id="versions">
<h2>API Version Support</h2>
<div class="informaltable">
<table style="border-collapse: collapse; border-top: 2px solid ; border-bottom: 2px solid ; border-left: 2px solid ; border-right: 2px solid ; ">
<colgroup>
<col style="text-align: left; "/>
<col style="text-align: center; " class="firstvers"/>
<col style="text-align: center; "/>
<col style="text-align: center; " class="lastvers"/>
</colgroup>
<thead>
<tr>
<th style="text-align: left; border-right: 2px solid ; ">
</th>
<th style="text-align: center; border-bottom: 2px solid ; " colspan="3">
<span class="bold"><strong>OpenGL ES API Version</strong></span>
</th>
</tr>
<tr>
<th style="text-align: left; border-right: 2px solid ; border-bottom: 2px solid ; ">
<span class="bold"><strong>Function Name</strong></span>
</th>
<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">
<span class="bold"><strong>2.0</strong></span>
</th>
<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">
<span class="bold"><strong>3.0</strong></span>
</th>
<th style="text-align: center; border-bottom: 2px solid ; ">
<span class="bold"><strong>3.1</strong></span>
</th>
</tr>
</thead>
<tbody>
<tr>
<td style="text-align: left; border-right: 2px solid ; ">glDrawRangeElements</td>
<td style="text-align: center; border-right: 2px solid ; ">-</td>
<td style="text-align: center; border-right: 2px solid ; ">✔</td>
<td style="text-align: center; ">✔</td>
</tr>
</tbody>
</table>
</div>
</div>
<div class="refsect1" id="seealso">
<h2>See Also</h2>
<p>
<a class="citerefentry" href="glCheckFramebufferStatus"><span class="citerefentry"><span class="refentrytitle">glCheckFramebufferStatus</span></span></a>,
<a class="citerefentry" href="glDisableVertexAttribArray"><span class="citerefentry"><span class="refentrytitle">glDisableVertexAttribArray</span></span></a>,
<a class="citerefentry" href="glDrawArrays"><span class="citerefentry"><span class="refentrytitle">glDrawArrays</span></span></a>,
<a class="citerefentry" href="glDrawElements"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>,
<a class="citerefentry" href="glDrawArraysInstanced"><span class="citerefentry"><span class="refentrytitle">glDrawArraysInstanced</span></span></a>,
<a class="citerefentry" href="glDrawElementsInstanced"><span class="citerefentry"><span class="refentrytitle">glDrawElementsInstanced</span></span></a>,
<a class="citerefentry" href="glEnableVertexAttribArray"><span class="citerefentry"><span class="refentrytitle">glEnableVertexAttribArray</span></span></a>,
</p>
</div>
<div class="refsect1" id="Copyright">
<h2>Copyright</h2>
<p>
Copyright © 1991-2006 Silicon Graphics, Inc.
Copyright © 2010-2014 Khronos Group.
This document is licensed under the SGI Free Software B License.
For details, see
<a class="link" href="https://web.archive.org/web/20171022161616/http://oss.sgi.com/projects/FreeB/" target="_top">https://web.archive.org/web/20171022161616/http://oss.sgi.com/projects/FreeB/</a>.
</p>
</div>
</div>