upstream-doc/manglsl/textureLodOffset.xml

   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="textureLodOffsetOffset">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>2011</year>
   9                 <holder>Khronos Group</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>textureLodOffset</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>textureLodOffset</refname>
  17         <refpurpose>perform a texture lookup with explicit level-of-detail and offset</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>Declaration</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>gvec4 <function>textureLodOffset</function></funcdef>
  23                 <paramdef>gsampler1D <parameter>sampler</parameter></paramdef>
  24                 <paramdef>float <parameter>P</parameter></paramdef>
  25                 <paramdef>float <parameter>lod</parameter></paramdef>
  26                 <paramdef>int <parameter>offset</parameter></paramdef>
  27             </funcprototype>
  28             <funcprototype>
  29                 <funcdef>gvec4 <function>textureLodOffset</function></funcdef>
  30                 <paramdef>gsampler2D <parameter>sampler</parameter></paramdef>
  31                 <paramdef>vec2 <parameter>P</parameter></paramdef>
  32                 <paramdef>float <parameter>lod</parameter></paramdef>
  33                 <paramdef>ivec2 <parameter>offset</parameter></paramdef>
  34             </funcprototype>
  35             <funcprototype>
  36                 <funcdef>gvec4 <function>textureLodOffset</function></funcdef>
  37                 <paramdef>gsampler3D <parameter>sampler</parameter></paramdef>
  38                 <paramdef>vec3 <parameter>P</parameter></paramdef>
  39                 <paramdef>float <parameter>lod</parameter></paramdef>
  40                 <paramdef>ivec3 <parameter>offset</parameter></paramdef>
  41             </funcprototype>
  42             <funcprototype>
  43                 <funcdef>float <function>textureLodOffset</function></funcdef>
  44                 <paramdef>sampler1DShadow <parameter>sampler</parameter></paramdef>
  45                 <paramdef>vec3 <parameter>P</parameter></paramdef>
  46                 <paramdef>float <parameter>lod</parameter></paramdef>
  47                 <paramdef>int <parameter>offset</parameter></paramdef>
  48             </funcprototype>
  49             <funcprototype>
  50                 <funcdef>float <function>textureLodOffset</function></funcdef>
  51                 <paramdef>sampler2DShadow <parameter>sampler</parameter></paramdef>
  52                 <paramdef>vec4 <parameter>P</parameter></paramdef>
  53                 <paramdef>float <parameter>lod</parameter></paramdef>
  54                 <paramdef>ivec2 <parameter>offset</parameter></paramdef>
  55             </funcprototype>
  56             <funcprototype>
  57                 <funcdef>gvec4 <function>textureLodOffset</function></funcdef>
  58                 <paramdef>gsampler1DArray <parameter>sampler</parameter></paramdef>
  59                 <paramdef>vec2 <parameter>P</parameter></paramdef>
  60                 <paramdef>float <parameter>lod</parameter></paramdef>
  61                 <paramdef>int <parameter>offset</parameter></paramdef>
  62             </funcprototype>
  63             <funcprototype>
  64                 <funcdef>gvec4 <function>textureLodOffset</function></funcdef>
  65                 <paramdef>gsampler2DArray <parameter>sampler</parameter></paramdef>
  66                 <paramdef>vec3 <parameter>P</parameter></paramdef>
  67                 <paramdef>float <parameter>lod</parameter></paramdef>
  68                 <paramdef>ivec2 <parameter>offset</parameter></paramdef>
  69             </funcprototype>
  70             <funcprototype>
  71                 <funcdef>float <function>textureLodOffset</function></funcdef>
  72                 <paramdef>sampler1DArrayShadow <parameter>sampler</parameter></paramdef>
  73                 <paramdef>vec3 <parameter>P</parameter></paramdef>
  74                 <paramdef>float <parameter>lod</parameter></paramdef>
  75                 <paramdef>int <parameter>offset</parameter></paramdef>
  76             </funcprototype>
  77         </funcsynopsis>
  78     </refsynopsisdiv>
  79     <refsect1 id="parameters"><title>Parameters</title>
  80         <variablelist>
  81         <varlistentry>
  82             <term><parameter>sampler</parameter></term>
  83             <listitem>
  84                 <para>
  85                     Specifies the sampler to which the texture from which texels will be retrieved is bound.
  86                 </para>
  87             </listitem>
  88         </varlistentry>
  89         <varlistentry>
  90             <term><parameter>P</parameter></term>
  91             <listitem>
  92                 <para>
  93                     Specifies the texture coordinates at which the texture will be sampled.
  94                 </para>
  95             </listitem>
  96         </varlistentry>
  97         <varlistentry>
  98             <term><parameter>lod</parameter></term>
  99             <listitem>
 100                 <para>
 101                     Specifies the explicit level-of-detail from which texels will be fetched.
 102                 </para>
 103             </listitem>
 104         </varlistentry>
 105         <varlistentry>
 106             <term><parameter>offset</parameter></term>
 107             <listitem>
 108                 <para>
 109                     Specifies the offset that will be applied to <parameter>P</parameter> before texels are fetched.
 110                 </para>
 111             </listitem>
 112         </varlistentry>
 113         </variablelist>
 114     </refsect1>
 115     <refsect1 id="description"><title>Description</title>
 116         <para>
 117             <function>textureLodOffset</function> performs a texture lookup at coordinate <parameter>P</parameter> from the
 118             texture bound to <parameter>sampler</parameter> with an explicit level-of-detail as specified in <parameter>lod</parameter>.
 119             Behavior is the same as in <citerefentry><refentrytitle>textureLod</refentrytitle></citerefentry> except that before
 120             sampling, <parameter>offset</parameter> is added to <parameter>P</parameter>.
 121         </para>
 122     </refsect1>
 123     <refsect1 id="versions"><title>Version Support</title>
 124         <informaltable frame="topbot">
 125             #VARTABLECOLS#
 126                 <thead>
 127                     #FUNCTABLEHEADER#
 128                     <row>
 129                         <entry>textureLodOffset</entry>#newin13#
 130                     </row>
 131                     <row>
 132                         <entry>textureLodOffset (gsampler2DRect{Shadow})</entry>#newin14#
 133                     </row>
 134                     <row>
 135                         <entry>textureLodOffset (gsamplerCubeArray)</entry>#newin40#
 136                     </row>
 137                 </thead>
 138             </tgroup>
 139         </informaltable>
 140     </refsect1>
 141     <refsect1 id="seealso"><title>See Also</title>
 142         <para>
 143             <citerefentry><refentrytitle>texelFetch</refentrytitle></citerefentry>,
 144             <citerefentry><refentrytitle>texelFetchOffset</refentrytitle></citerefentry>,
 145             <citerefentry><refentrytitle>texture</refentrytitle></citerefentry>,
 146             <citerefentry><refentrytitle>textureGather</refentrytitle></citerefentry>,
 147             <citerefentry><refentrytitle>textureGatherOffset</refentrytitle></citerefentry>,
 148             <citerefentry><refentrytitle>textureGatherOffsets</refentrytitle></citerefentry>,
 149             <citerefentry><refentrytitle>textureGrad</refentrytitle></citerefentry>,
 150             <citerefentry><refentrytitle>textureGradOffset</refentrytitle></citerefentry>,
 151             <citerefentry><refentrytitle>textureLod</refentrytitle></citerefentry>,
 152             <citerefentry><refentrytitle>textureOffset</refentrytitle></citerefentry>,
 153             <citerefentry><refentrytitle>textureProj</refentrytitle></citerefentry>,
 154             <citerefentry><refentrytitle>textureProjGrad</refentrytitle></citerefentry>,
 155             <citerefentry><refentrytitle>textureProjGradOffset</refentrytitle></citerefentry>,
 156             <citerefentry><refentrytitle>textureProjLod</refentrytitle></citerefentry>,
 157             <citerefentry><refentrytitle>textureProjLodOffset</refentrytitle></citerefentry>,
 158             <citerefentry><refentrytitle>textureProjOffset</refentrytitle></citerefentry>,
 159             <citerefentry><refentrytitle>textureQueryLod</refentrytitle></citerefentry>,
 160             <citerefentry><refentrytitle>textureSize</refentrytitle></citerefentry>
 161         </para>
 162     </refsect1>
 163     <refsect1 id="Copyright"><title>Copyright</title>
 164         <para>
 165             Copyright <trademark class="copyright"></trademark> 2011 Khronos Group.
 166             This material may be distributed subject to the terms and conditions set forth in
 167             the Open Publication License, v 1.0, 8 June 1999.
 168             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
 169         </para>
 170     </refsect1>
 171 </refentry>