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renderer=
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"text/html; charset=UTF-8" /><link rel=
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"text/css" href=
"opengl-man.css" /><title>texture - OpenGL Shading Language (GLSL)
</title><meta name=
"generator" content=
"DocBook XSL Stylesheets V1.69.1" /></head><body><div class=
"refentry" lang=
"en" xml:
lang=
"en"><a id=
"texture"></a><div class=
"titlepage"></div><div class=
"refnamediv"><h2>Name
</h2><p>texture — retrieves texels from a texture
</p></div><div class=
"refsynopsisdiv"><h2>Declaration
</h2><div class=
"funcsynopsis"><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0" style=
"padding-bottom: 1em"><tr><td><code class=
"funcdef">gvec4
<b class=
"fsfunc">texture
</b>(
</code></td><td>gsampler1D
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>float
</td><td><var class=
"pdparam">P
</var>,
</td></tr><tr><td> </td><td>[float
</td><td><var class=
"pdparam">bias
</var>]
<code>)
</code>;
</td></tr></table><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0" style=
"padding-bottom: 1em"><tr><td><code class=
"funcdef">gvec4
<b class=
"fsfunc">texture
</b>(
</code></td><td>gsampler2D
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>vec2
</td><td><var class=
"pdparam">P
</var>,
</td></tr><tr><td> </td><td>[float
</td><td><var class=
"pdparam">bias
</var>]
<code>)
</code>;
</td></tr></table><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0" style=
"padding-bottom: 1em"><tr><td><code class=
"funcdef">gvec4
<b class=
"fsfunc">texture
</b>(
</code></td><td>gsampler3D
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>vec3
</td><td><var class=
"pdparam">P
</var>,
</td></tr><tr><td> </td><td>[float
</td><td><var class=
"pdparam">bias
</var>]
<code>)
</code>;
</td></tr></table><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0" style=
"padding-bottom: 1em"><tr><td><code class=
"funcdef">gvec4
<b class=
"fsfunc">texture
</b>(
</code></td><td>gsamplerCube
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>vec3
</td><td><var class=
"pdparam">P
</var>,
</td></tr><tr><td> </td><td>[float
</td><td><var class=
"pdparam">bias
</var>]
<code>)
</code>;
</td></tr></table><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0" style=
"padding-bottom: 1em"><tr><td><code class=
"funcdef">float
<b class=
"fsfunc">texture
</b>(
</code></td><td>sampler1DShadow
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>vec3
</td><td><var class=
"pdparam">P
</var>,
</td></tr><tr><td> </td><td>[float
</td><td><var class=
"pdparam">bias
</var>]
<code>)
</code>;
</td></tr></table><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0" style=
"padding-bottom: 1em"><tr><td><code class=
"funcdef">float
<b class=
"fsfunc">texture
</b>(
</code></td><td>sampler2DShadow
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>vec3
</td><td><var class=
"pdparam">P
</var>,
</td></tr><tr><td> </td><td>[float
</td><td><var class=
"pdparam">bias
</var>]
<code>)
</code>;
</td></tr></table><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0" style=
"padding-bottom: 1em"><tr><td><code class=
"funcdef">float
<b class=
"fsfunc">texture
</b>(
</code></td><td>samplerCubeShadow
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>vec3
</td><td><var class=
"pdparam">P
</var>,
</td></tr><tr><td> </td><td>[float
</td><td><var class=
"pdparam">bias
</var>]
<code>)
</code>;
</td></tr></table><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0" style=
"padding-bottom: 1em"><tr><td><code class=
"funcdef">gvec4
<b class=
"fsfunc">texture
</b>(
</code></td><td>gsampler1DArray
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>vec2
</td><td><var class=
"pdparam">P
</var>,
</td></tr><tr><td> </td><td>[float
</td><td><var class=
"pdparam">bias
</var>]
<code>)
</code>;
</td></tr></table><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0" style=
"padding-bottom: 1em"><tr><td><code class=
"funcdef">gvec4
<b class=
"fsfunc">texture
</b>(
</code></td><td>gsampler2DArray
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>vec3
</td><td><var class=
"pdparam">P
</var>,
</td></tr><tr><td> </td><td>[float
</td><td><var class=
"pdparam">bias
</var>]
<code>)
</code>;
</td></tr></table><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0" style=
"padding-bottom: 1em"><tr><td><code class=
"funcdef">gvec4
<b class=
"fsfunc">texture
</b>(
</code></td><td>gsamplerCubeArray
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>vec4
</td><td><var class=
"pdparam">P
</var>,
</td></tr><tr><td> </td><td>[float
</td><td><var class=
"pdparam">bias
</var>]
<code>)
</code>;
</td></tr></table><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0" style=
"padding-bottom: 1em"><tr><td><code class=
"funcdef">float
<b class=
"fsfunc">texture
</b>(
</code></td><td>sampler1DArrayShadow
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>vec3
</td><td><var class=
"pdparam">P
</var>,
</td></tr><tr><td> </td><td>[float
</td><td><var class=
"pdparam">bias
</var>]
<code>)
</code>;
</td></tr></table><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0" style=
"padding-bottom: 1em"><tr><td><code class=
"funcdef">float
<b class=
"fsfunc">texture
</b>(
</code></td><td>gsampler2DArrayShadow
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>vec4
</td><td><var class=
"pdparam">P
</var>,
</td></tr><tr><td> </td><td>[float
</td><td><var class=
"pdparam">bias
</var>]
<code>)
</code>;
</td></tr></table><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0" style=
"padding-bottom: 1em"><tr><td><code class=
"funcdef">gvec4
<b class=
"fsfunc">texture
</b>(
</code></td><td>gsampler2DRect
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>vec2
</td><td><var class=
"pdparam">P
</var><code>)
</code>;
</td></tr></table><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0" style=
"padding-bottom: 1em"><tr><td><code class=
"funcdef">float
<b class=
"fsfunc">texture
</b>(
</code></td><td>sampler2DRectShadow
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>vec3
</td><td><var class=
"pdparam">P
</var><code>)
</code>;
</td></tr></table><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0"><tr><td><code class=
"funcdef">float
<b class=
"fsfunc">texture
</b>(
</code></td><td>gsamplerCubeArrayShadow
</td><td><var class=
"pdparam">sampler
</var>,
</td></tr><tr><td> </td><td>vec4
</td><td><var class=
"pdparam">P
</var>,
</td></tr><tr><td> </td><td>float
</td><td><var class=
"pdparam">compare
</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>sampler
</code></em></span></dt><dd><p>
5 Specifies the sampler to which the texture from which texels will be retrieved is bound.
6 </p></dd><dt><span class=
"term"><em class=
"parameter"><code>P
</code></em></span></dt><dd><p>
7 Specifies the texture coordinates at which texture will be sampled.
8 </p></dd><dt><span class=
"term"><em class=
"parameter"><code>bias
</code></em></span></dt><dd><p>
9 Specifies an optional bias to be applied during level-of-detail computation.
10 </p></dd><dt><span class=
"term"><em class=
"parameter"><code>compare
</code></em></span></dt><dd><p>
11 Specifies the value to which the fetched texel will be compared when sampling from
<code class=
"code">gsamplerCubeArrayShadow
</code>.
12 </p></dd></dl></div></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"description"></a><h2>Description
</h2><p>
13 <code class=
"function">texture
</code> samples texels from the texture bound to
<em class=
"parameter"><code>sampler
</code></em> at texture
14 coordinate
<em class=
"parameter"><code>P
</code></em>. An optional bias, specified in
<em class=
"parameter"><code>bias
</code></em> is included in
15 the level-of-detail computation that is used to choose mipmap(s) from which to sample.
17 For
<span class=
"emphasis"><em>shadow
</em></span> forms, when
<em class=
"parameter"><code>compare
</code></em> is present, it is used as
18 <mml:math xmlns:
mml=
"http://www.w3.org/1998/Math/MathML" overflow=
"scroll"><mml:msub><mml:mi>D
</mml:mi><mml:mi>sub
</mml:mi></mml:msub></mml:math>
19 and the array layer is specified in
<code class=
"code"><em class=
"parameter"><code>P
</code></em>.w
</code>. When
<em class=
"parameter"><code>compare
</code></em> is
20 not present, the last component of
<em class=
"parameter"><code>P
</code></em> is used as
21 <mml:math xmlns:
mml=
"http://www.w3.org/1998/Math/MathML" overflow=
"scroll"><mml:msub><mml:mi>D
</mml:mi><mml:mi>sub
</mml:mi></mml:msub></mml:math> and the
22 array layer is specified in the second to last component of
<em class=
"parameter"><code>P
</code></em>. (The second component of
<em class=
"parameter"><code>P
</code></em>
23 is unused for
<span class=
"emphasis"><em>1D
</em></span> shadow lookups.)
25 For non-shadow variants, the array layer comes from the last component of
<em class=
"parameter"><code>P
</code></em>.
26 </p></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"versions"></a><h2>Version Support
</h2><div class=
"informaltable"><table border=
"1"><colgroup><col align=
"left" /><col align=
"center" /><col align=
"center" /><col align=
"center" /><col align=
"center" /><col align=
"center" /><col align=
"center" /><col align=
"center" /><col align=
"center" /><col align=
"center" /><col align=
"center" /></colgroup><thead><tr><th align=
"left"><span class=
"bold"><strong>Function
</strong></span></th><th align=
"left"><span class=
"bold"><strong>Version
1.10</strong></span></th><th align=
"left"><span class=
"bold"><strong>Version
1.20</strong></span></th><th align=
"left"><span class=
"bold"><strong>Version
1.30</strong></span></th><th align=
"left"><span class=
"bold"><strong>Version
1.40</strong></span></th><th align=
"left"><span class=
"bold"><strong>Version
1.50</strong></span></th><th align=
"left"><span class=
"bold"><strong>Version
3.30</strong></span></th><th align=
"left"><span class=
"bold"><strong>Version
4.00</strong></span></th><th align=
"left"><span class=
"bold"><strong>Version
4.10</strong></span></th><th align=
"left"><span class=
"bold"><strong>Version
4.20</strong></span></th><th align=
"center"><span class=
"bold"><strong>Version
4.30</strong></span></th></tr><tr><th align=
"left">texture
</th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th></tr><tr><th align=
"left">texture (gsampler2DRect{Shadow})
</th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th></tr><tr><th align=
"left">texture (gsampler2DMS, gsampler2DMSArray)
</th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th></tr><tr><th align=
"left">texture (gsamplerCubeArray{Shadow})
</th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>-
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th><th align=
"center"><span class=
"emphasis"><em>Y
</em></span></th></tr></thead></table></div></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"seealso"></a><h2>See Also
</h2><p>
27 <a href=
"texelFetch.xml"><span class=
"citerefentry"><span class=
"refentrytitle">texelFetch
</span></span></a>,
28 <a href=
"texelFetchOffset.xml"><span class=
"citerefentry"><span class=
"refentrytitle">texelFetchOffset
</span></span></a>,
29 <a href=
"textureGather.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureGather
</span></span></a>,
30 <a href=
"textureGatherOffset.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureGatherOffset
</span></span></a>,
31 <a href=
"textureGatherOffsets.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureGatherOffsets
</span></span></a>,
32 <a href=
"textureGrad.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureGrad
</span></span></a>,
33 <a href=
"textureGradOffset.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureGradOffset
</span></span></a>,
34 <a href=
"textureLod.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureLod
</span></span></a>,
35 <a href=
"textureLodOffset.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureLodOffset
</span></span></a>,
36 <a href=
"textureOffset.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureOffset
</span></span></a>,
37 <a href=
"textureProj.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureProj
</span></span></a>,
38 <a href=
"textureProjGrad.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureProjGrad
</span></span></a>,
39 <a href=
"textureProjGradOffset.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureProjGradOffset
</span></span></a>,
40 <a href=
"textureProjLod.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureProjLod
</span></span></a>,
41 <a href=
"textureProjLodOffset.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureProjLodOffset
</span></span></a>,
42 <a href=
"textureProjOffset.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureProjOffset
</span></span></a>,
43 <a href=
"textureQueryLod.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureQueryLod
</span></span></a>,
44 <a href=
"textureSize.xml"><span class=
"citerefentry"><span class=
"refentrytitle">textureSize
</span></span></a>
45 </p></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"Copyright"></a><h2>Copyright
</h2><p>
46 Copyright
<span class=
"trademark"></span>©
2011 Khronos Group.
47 This material may be distributed subject to the terms and conditions set forth in
48 the Open Publication License, v
1.0,
8 June
1999.
49 <a href=
"http://opencontent.org/openpub/" target=
"_top">http://opencontent.org/openpub/
</a>.
50 </p></div></div></body></html>