<div class="refentry" id="gl_SamplePosition">

<div class="titlepage"></div>

<div class="refnamediv">

<h2>Name</h2>

<p>gl_SamplePosition — contains the location of the current sample within the current fragment</p>

</div>

<div class="refsynopsisdiv">

<h2>Declaration</h2>

<code class="fieldsynopsis"><span class="modifier">in </span><span class="type">vec2 </span><span class="varname">gl_SamplePosition </span>;</code>

</div>

<div class="refsect1" id="description">

<h2>Description</h2>

<p>

<code class="varname">gl_SamplePosition</code> is a fragment language input variable that contains

the location within a fragment of the sample currently being processed. The x and y components

of <code class="varname">gl_SamplePosition</code> contain the sub-pixel coordinate of the current

sample and will have values in the range 0.0 to 1.0. The sub-pixel coordinates of the center

of the pixel are always (0.5, 0.5). Any static use of <code class="varname">gl_SamplePosition</code>

causes the entire fragment shader to be evaluated per-sample rather than per-fragment. When rendering

to a non-multisample buffer, or if multisample rasterization is disabled, <code class="varname">gl_SamplePosition</code>

will be (0.5, 0.5).

</p>

</div>

{$pipelinestall}{$examples}

<div class="refsect1" id="versions">

<h2>Version Support</h2>

<div class="informaltable">

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<thead>

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<th style="text-align: center; border-bottom: 2px solid ; " colspan="12">

<span class="bold"><strong>OpenGL Shading Language 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>

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<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">

<span class="bold"><strong>1.10</strong></span>

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<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">

<span class="bold"><strong>1.20</strong></span>

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<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">

<span class="bold"><strong>1.30</strong></span>

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<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">

<span class="bold"><strong>1.40</strong></span>

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<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">

<span class="bold"><strong>1.50</strong></span>

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<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">

<span class="bold"><strong>3.30</strong></span>

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<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">

<span class="bold"><strong>4.00</strong></span>

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<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">

<span class="bold"><strong>4.10</strong></span>

</th>

<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">

<span class="bold"><strong>4.20</strong></span>

</th>

<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">

<span class="bold"><strong>4.30</strong></span>

</th>

<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">

<span class="bold"><strong>4.40</strong></span>

</th>

<th style="text-align: center; border-bottom: 2px solid ; ">

<span class="bold"><strong>4.50</strong></span>

</th>

</tr>

</thead>

<tbody>

<tr>

<td style="text-align: left; border-right: 2px solid ; ">gl_SamplePosition</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; border-right: 2px solid ; ">-</td>

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<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; border-right: 2px solid ; ">✔</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; 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="gl_SampleID"><span class="citerefentry"><span class="refentrytitle">gl_SampleID</span></span></a>,

<a class="citerefentry" href="gl_SampleMask"><span class="citerefentry"><span class="refentrytitle">gl_SampleMask</span></span></a>,

<a class="citerefentry" href="gl_FragCoord"><span class="citerefentry"><span class="refentrytitle">gl_FragCoord</span></span></a>

</p>

</div>

<div class="refsect1" id="Copyright">

<h2>Copyright</h2>

<p>

Copyright © 2011-2014 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 class="link" href="https://opencontent.org/openpub/" target="_top">https://opencontent.org/openpub/</a>.

</p>

</div>

</div>