1 <?xml version=
"1.0" encoding=
"UTF-8"?>
2 <!DOCTYPE book PUBLIC
"-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
3 "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
4 <refentry id=
"textureProjLod">
9 <holder>Khronos Group
</holder>
12 <refentrytitle>textureProjLod
</refentrytitle>
13 <manvolnum>3G
</manvolnum>
16 <refname>textureProjLod
</refname>
17 <refpurpose>perform a texture lookup with projection and explicit level-of-detail
</refpurpose>
19 <refsynopsisdiv><title>Declaration
</title>
22 <funcdef>gvec4
<function>textureProjLod
</function></funcdef>
23 <paramdef>gsampler1D
<parameter>sampler
</parameter></paramdef>
24 <paramdef>vec2
<parameter>P
</parameter></paramdef>
25 <paramdef>float
<parameter>lod
</parameter></paramdef>
28 <funcdef>gvec4
<function>textureProjLod
</function></funcdef>
29 <paramdef>gsampler1D
<parameter>sampler
</parameter></paramdef>
30 <paramdef>vec4
<parameter>P
</parameter></paramdef>
31 <paramdef>float
<parameter>lod
</parameter></paramdef>
34 <funcdef>gvec4
<function>textureProjLod
</function></funcdef>
35 <paramdef>gsampler2D
<parameter>sampler
</parameter></paramdef>
36 <paramdef>vec3
<parameter>P
</parameter></paramdef>
37 <paramdef>float
<parameter>lod
</parameter></paramdef>
40 <funcdef>gvec4
<function>textureProjLod
</function></funcdef>
41 <paramdef>gsampler2D
<parameter>sampler
</parameter></paramdef>
42 <paramdef>vec4
<parameter>P
</parameter></paramdef>
43 <paramdef>float
<parameter>lod
</parameter></paramdef>
46 <funcdef>gvec4
<function>textureProjLod
</function></funcdef>
47 <paramdef>gsampler3D
<parameter>sampler
</parameter></paramdef>
48 <paramdef>vec4
<parameter>P
</parameter></paramdef>
49 <paramdef>float
<parameter>lod
</parameter></paramdef>
52 <funcdef>float
<function>textureProjLod
</function></funcdef>
53 <paramdef>sampler1DShadow
<parameter>sampler
</parameter></paramdef>
54 <paramdef>vec4
<parameter>P
</parameter></paramdef>
55 <paramdef>float
<parameter>lod
</parameter></paramdef>
58 <funcdef>float
<function>textureProjLod
</function></funcdef>
59 <paramdef>sampler2DShadow
<parameter>sampler
</parameter></paramdef>
60 <paramdef>vec4
<parameter>P
</parameter></paramdef>
61 <paramdef>float
<parameter>lod
</parameter></paramdef>
65 <refsect1 id=
"parameters"><title>Parameters
</title>
68 <term><parameter>sampler
</parameter></term>
71 Specifies the sampler to which the texture from which texels will be retrieved is bound.
76 <term><parameter>P
</parameter></term>
79 Specifies the texture coordinates at which texture will be sampled.
84 <term><parameter>lod
</parameter></term>
87 Specifies the explicit level-of-detail from which to fetch texels.
93 <refsect1 id=
"description"><title>Description
</title>
95 <function>textureProjLod
</function> performs a texture lookup with projection from an explicitly specified level-of-detail. The texture coordinates
96 consumed from
<parameter>P
</parameter>, not including the last component of
<parameter>P
</parameter>,
97 are divided by the last component of
<parameter>P
</parameter>. The resulting
<inlineequation><mml:math><mml:msup><mml:mn>3</mml:mn><mml:mi>rd
</mml:mi></mml:msup></mml:math></inlineequation>
98 component of
<parameter>P
</parameter> in the shadow forms is used as
99 <inlineequation><mml:math><mml:msub><mml:mi>D
</mml:mi><mml:mi>ref
</mml:mi></mml:msub></mml:math></inlineequation>.
100 After these values are computed, the texture lookup proceeds as in
<citerefentry><refentrytitle>textureLod
</refentrytitle></citerefentry>,
101 with
<parameter>lod
</parameter> used to specify the level-of-detail from which the texture will be sampled.
104 <refsect1 id=
"versions"><title>Version Support
</title>
105 <informaltable frame=
"topbot">
110 <entry>textureProjLod
</entry>#newin13#
116 <refsect1 id=
"seealso"><title>See Also
</title>
118 <citerefentry><refentrytitle>texelFetch
</refentrytitle></citerefentry>,
119 <citerefentry><refentrytitle>texelFetchOffset
</refentrytitle></citerefentry>,
120 <citerefentry><refentrytitle>texture
</refentrytitle></citerefentry>,
121 <citerefentry><refentrytitle>textureGather
</refentrytitle></citerefentry>,
122 <citerefentry><refentrytitle>textureGatherOffset
</refentrytitle></citerefentry>,
123 <citerefentry><refentrytitle>textureGatherOffsets
</refentrytitle></citerefentry>,
124 <citerefentry><refentrytitle>textureGrad
</refentrytitle></citerefentry>,
125 <citerefentry><refentrytitle>textureGradOffset
</refentrytitle></citerefentry>,
126 <citerefentry><refentrytitle>textureLod
</refentrytitle></citerefentry>,
127 <citerefentry><refentrytitle>textureLodOffset
</refentrytitle></citerefentry>,
128 <citerefentry><refentrytitle>textureOffset
</refentrytitle></citerefentry>,
129 <citerefentry><refentrytitle>textureProj
</refentrytitle></citerefentry>,
130 <citerefentry><refentrytitle>textureProjGrad
</refentrytitle></citerefentry>,
131 <citerefentry><refentrytitle>textureProjGradOffset
</refentrytitle></citerefentry>,
132 <citerefentry><refentrytitle>textureProjLodOffset
</refentrytitle></citerefentry>,
133 <citerefentry><refentrytitle>textureProjOffset
</refentrytitle></citerefentry>,
134 <citerefentry><refentrytitle>textureQueryLod
</refentrytitle></citerefentry>,
135 <citerefentry><refentrytitle>textureSize
</refentrytitle></citerefentry>
138 <refsect1 id=
"Copyright"><title>Copyright
</title>
140 Copyright
<trademark class=
"copyright"></trademark> 2011 Khronos Group.
141 This material may be distributed subject to the terms and conditions set forth in
142 the Open Publication License, v
1.0,
8 June
1999.
143 <ulink url=
"http://opencontent.org/openpub/">http://opencontent.org/openpub/
</ulink>.