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glDrawRangeElements.xhtml
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<div class="refentry" lang="en" xml:lang="en"><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><tr><td><code class="funcdef">void <b class="fsfunc">glDrawRangeElements</b>(</code></td><td>GLenum </td><td><var class="pdparam">mode</var>, </td></tr><tr><td> </td><td>GLuint </td><td><var class="pdparam">start</var>, </td></tr><tr><td> </td><td>GLuint </td><td><var class="pdparam">end</var>, </td></tr><tr><td> </td><td>GLsizei </td><td><var class="pdparam">count</var>, </td></tr><tr><td> </td><td>GLenum </td><td><var class="pdparam">type</var>, </td></tr><tr><td> </td><td>const GLvoid * </td><td><var class="pdparam">indices</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>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_LINE_STRIP_ADJACENCY</code>,
<code class="constant">GL_LINES_ADJACENCY</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_TRIANGLE_STRIP_ADJACENCY</code> and
<code class="constant">GL_TRIANGLES_ADJACENCY</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" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
<code class="function">glDrawRangeElements</code> is a restricted form of <a href="glDrawElements"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>. <em class="parameter"><code>mode</code></em>, <em class="parameter"><code>start</code></em>, <em class="parameter"><code>end</code></em>,
and <em class="parameter"><code>count</code></em> match the corresponding arguments to <a 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 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
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<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>
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</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>
Vertex attributes that are modified by <code class="function">glDrawRangeElements</code> have an
unspecified value after <code class="function">glDrawRangeElements</code> returns. Attributes that aren't
modified maintain their previous values.
</p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
<code class="constant">GL_LINE_STRIP_ADJACENCY</code>,
<code class="constant">GL_LINES_ADJACENCY</code>,
<code class="constant">GL_TRIANGLE_STRIP_ADJACENCY</code> and
<code class="constant">GL_TRIANGLES_ADJACENCY</code>
are available only if the GL version is 3.2 or greater.
</p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><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
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<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 geometry shader is active and <em class="parameter"><code>mode</code></em>
is incompatible with the input primitive type of the geometry shader in the currently installed program object.
</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></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
<a 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 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" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
<a href="glDrawArrays"><span class="citerefentry"><span class="refentrytitle">glDrawArrays</span></span></a>,
<a href="glDrawElements"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>,
<a href="glDrawElementsBaseVertex"><span class="citerefentry"><span class="refentrytitle">glDrawElementsBaseVertex</span></span></a>
</p></div><div class="refsect1" lang="en" xml:lang="en"><div id="Copyright"><h2>Copyright</h2><p>
Copyright © 1991-2006
Silicon Graphics, Inc. This document is licensed under the SGI
Free Software B License. For details, see
<a 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></div>