upstream-man-pages/manglsl/textureProjGradOffset.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="textureProjGradOffsetGrad">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>2011</year>
   9                 <holder>Khronos Group</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>textureProjGradOffset</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>textureProjGradOffset</refname>
  17         <refpurpose>perform a texture lookup with projection, explicit gradients and offset</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>Declaration</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>gvec4 <function>textureProjGradOffset</function></funcdef>
  23                 <paramdef>gsampler1D <parameter>sampler</parameter></paramdef>
  24                 <paramdef>vec2 <parameter>P</parameter></paramdef>
  25                 <paramdef>float <parameter>dPdx</parameter></paramdef>
  26                 <paramdef>float <parameter>dPdy</parameter></paramdef>
  27                 <paramdef>int <parameter>offset</parameter></paramdef>
  28             </funcprototype>
  29             <funcprototype>
  30                 <funcdef>gvec4 <function>textureProjGradOffset</function></funcdef>
  31                 <paramdef>gsampler1D <parameter>sampler</parameter></paramdef>
  32                 <paramdef>vec4 <parameter>P</parameter></paramdef>
  33                 <paramdef>float <parameter>dPdx</parameter></paramdef>
  34                 <paramdef>float <parameter>dPdy</parameter></paramdef>
  35                 <paramdef>int <parameter>offset</parameter></paramdef>
  36             </funcprototype>
  37             <funcprototype>
  38                 <funcdef>gvec4 <function>textureProjGradOffset</function></funcdef>
  39                 <paramdef>gsampler2D <parameter>sampler</parameter></paramdef>
  40                 <paramdef>vec3 <parameter>P</parameter></paramdef>
  41                 <paramdef>vec2 <parameter>dPdx</parameter></paramdef>
  42                 <paramdef>vec2 <parameter>dPdy</parameter></paramdef>
  43                 <paramdef>ivec2 <parameter>offset</parameter></paramdef>
  44             </funcprototype>
  45             <funcprototype>
  46                 <funcdef>gvec4 <function>textureProjGradOffset</function></funcdef>
  47                 <paramdef>gsampler2D <parameter>sampler</parameter></paramdef>
  48                 <paramdef>vec4 <parameter>P</parameter></paramdef>
  49                 <paramdef>vec2 <parameter>dPdx</parameter></paramdef>
  50                 <paramdef>vec2 <parameter>dPdy</parameter></paramdef>
  51                 <paramdef>ivec2 <parameter>offset</parameter></paramdef>
  52             </funcprototype>
  53             <funcprototype>
  54                 <funcdef>gvec4 <function>textureProjGradOffset</function></funcdef>
  55                 <paramdef>gsampler3D <parameter>sampler</parameter></paramdef>
  56                 <paramdef>vec4 <parameter>P</parameter></paramdef>
  57                 <paramdef>vec3 <parameter>dPdx</parameter></paramdef>
  58                 <paramdef>vec3 <parameter>dPdy</parameter></paramdef>
  59                 <paramdef>ivec3 <parameter>offset</parameter></paramdef>
  60             </funcprototype>
  61             <funcprototype>
  62                 <funcdef>float <function>textureProjGradOffset</function></funcdef>
  63                 <paramdef>sampler1DShadow <parameter>sampler</parameter></paramdef>
  64                 <paramdef>vec4 <parameter>P</parameter></paramdef>
  65                 <paramdef>float <parameter>dPdx</parameter></paramdef>
  66                 <paramdef>float <parameter>dPdy</parameter></paramdef>
  67                 <paramdef>int <parameter>offset</parameter></paramdef>
  68             </funcprototype>
  69             <funcprototype>
  70                 <funcdef>float <function>textureProjGradOffset</function></funcdef>
  71                 <paramdef>sampler2DShadow <parameter>sampler</parameter></paramdef>
  72                 <paramdef>vec4 <parameter>P</parameter></paramdef>
  73                 <paramdef>vec2 <parameter>dPdx</parameter></paramdef>
  74                 <paramdef>vec2 <parameter>dPdy</parameter></paramdef>
  75                 <paramdef>ivec2 <parameter>offset</parameter></paramdef>
  76             </funcprototype>
  77             <funcprototype>
  78                 <funcdef>gvec4 <function>textureProjGradOffset</function></funcdef>
  79                 <paramdef>gsampler2DRect <parameter>sampler</parameter></paramdef>
  80                 <paramdef>vec3 <parameter>P</parameter></paramdef>
  81                 <paramdef>vec2 <parameter>dPdx</parameter></paramdef>
  82                 <paramdef>vec2 <parameter>dPdy</parameter></paramdef>
  83                 <paramdef>ivec2 <parameter>offset</parameter></paramdef>
  84             </funcprototype>
  85             <funcprototype>
  86                 <funcdef>gvec4 <function>textureProjGradOffset</function></funcdef>
  87                 <paramdef>gsampler2DRect <parameter>sampler</parameter></paramdef>
  88                 <paramdef>vec4 <parameter>P</parameter></paramdef>
  89                 <paramdef>vec2 <parameter>dPdx</parameter></paramdef>
  90                 <paramdef>vec2 <parameter>dPdy</parameter></paramdef>
  91                 <paramdef>ivec2 <parameter>offset</parameter></paramdef>
  92             </funcprototype>
  93             <funcprototype>
  94                 <funcdef>float <function>textureProjGradOffset</function></funcdef>
  95                 <paramdef>gsampler2DRectShadow <parameter>sampler</parameter></paramdef>
  96                 <paramdef>vec4 <parameter>P</parameter></paramdef>
  97                 <paramdef>vec2 <parameter>dPdx</parameter></paramdef>
  98                 <paramdef>vec2 <parameter>dPdy</parameter></paramdef>
  99                 <paramdef>ivec2 <parameter>offset</parameter></paramdef>
 100             </funcprototype>
 101         </funcsynopsis>
 102     </refsynopsisdiv>
 103     <refsect1 id="parameters"><title>Parameters</title>
 104         <variablelist>
 105         <varlistentry>
 106             <term><parameter>sampler</parameter></term>
 107             <listitem>
 108                 <para>
 109                     Specifies the sampler to which the texture from which texels will be retrieved is bound.
 110                 </para>
 111             </listitem>
 112         </varlistentry>
 113         <varlistentry>
 114             <term><parameter>P</parameter></term>
 115             <listitem>
 116                 <para>
 117                     Specifies the texture coordinates at which texture will be sampled.
 118                 </para>
 119             </listitem>
 120         </varlistentry>
 121         <varlistentry>
 122             <term><parameter>dPdx</parameter></term>
 123             <listitem>
 124                 <para>
 125                     Specifies the partial derivative of <parameter>P</parameter> with respect to window x.
 126                 </para>
 127             </listitem>
 128         </varlistentry>
 129         <varlistentry>
 130             <term><parameter>dPdy</parameter></term>
 131             <listitem>
 132                 <para>
 133                     Specifies the partial derivative of <parameter>P</parameter> with respect to window y.
 134                 </para>
 135             </listitem>
 136         </varlistentry>
 137         <varlistentry>
 138             <term><parameter>offset</parameter></term>
 139             <listitem>
 140                 <para>
 141                     Specifies the offsets, in texels at which the texture will be sampled relative to the projection of <parameter>P</parameter>.
 142                 </para>
 143             </listitem>
 144         </varlistentry>
 145         </variablelist>
 146     </refsect1>
 147     <refsect1 id="description"><title>Description</title>
 148         <para>
 149             <function>textureProjGradOffset</function> performs a texture lookup with projection and explicit gradients and offsets. The texture coordinates
 150             consumed from <parameter>P</parameter>, not including the last component of <parameter>P</parameter>,
 151             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>
 152             component of <parameter>P</parameter> in the shadow forms is used as
 153             <inlineequation><mml:math><mml:msub><mml:mi>D</mml:mi><mml:mi>ref</mml:mi></mml:msub></mml:math></inlineequation>.
 154             After these values are computed, the texture lookup proceeds as in <citerefentry><refentrytitle>textureGradOffset</refentrytitle></citerefentry>,
 155             passing <parameter>dPdx</parameter> and <parameter>dPdy</parameter> as gradients, and <parameter>offset</parameter> as the offset.
 156         </para>
 157     </refsect1>
 158     <refsect1 id="versions"><title>Version Support</title>
 159         <informaltable frame="topbot">
 160             #VARTABLECOLS#
 161                 <thead>
 162                     #FUNCTABLEHEADER#
 163                     <row>
 164                         <entry>textureProjGradOffset</entry>#newin13#
 165                     </row>
 166                     <row>
 167                         <entry>textureProjGradOffset (gsampler2DRect{Shadow})</entry>#newin14#
 168                     </row>
 169                 </thead>
 170             </tgroup>
 171         </informaltable>
 172     </refsect1>
 173     <refsect1 id="seealso"><title>See Also</title>
 174         <para>
 175             <citerefentry><refentrytitle>texelFetch</refentrytitle></citerefentry>,
 176             <citerefentry><refentrytitle>texelFetchOffset</refentrytitle></citerefentry>,
 177             <citerefentry><refentrytitle>texture</refentrytitle></citerefentry>,
 178             <citerefentry><refentrytitle>textureGather</refentrytitle></citerefentry>,
 179             <citerefentry><refentrytitle>textureGatherOffset</refentrytitle></citerefentry>,
 180             <citerefentry><refentrytitle>textureGatherOffsets</refentrytitle></citerefentry>,
 181             <citerefentry><refentrytitle>textureGrad</refentrytitle></citerefentry>,
 182             <citerefentry><refentrytitle>textureGradOffset</refentrytitle></citerefentry>,
 183             <citerefentry><refentrytitle>textureLod</refentrytitle></citerefentry>,
 184             <citerefentry><refentrytitle>textureLodOffset</refentrytitle></citerefentry>,
 185             <citerefentry><refentrytitle>textureOffset</refentrytitle></citerefentry>,
 186             <citerefentry><refentrytitle>textureProj</refentrytitle></citerefentry>,
 187             <citerefentry><refentrytitle>textureProjGrad</refentrytitle></citerefentry>,
 188             <citerefentry><refentrytitle>textureProjLod</refentrytitle></citerefentry>,
 189             <citerefentry><refentrytitle>textureProjLodOffset</refentrytitle></citerefentry>,
 190             <citerefentry><refentrytitle>textureProjOffset</refentrytitle></citerefentry>,
 191             <citerefentry><refentrytitle>textureQueryLod</refentrytitle></citerefentry>,
 192             <citerefentry><refentrytitle>textureSize</refentrytitle></citerefentry>
 193         </para>
 194     </refsect1>
 195     <refsect1 id="Copyright"><title>Copyright</title>
 196         <para>
 197             Copyright <trademark class="copyright"></trademark> 2011 Khronos Group.
 198             This material may be distributed subject to the terms and conditions set forth in
 199             the Open Publication License, v 1.0, 8 June 1999.
 200             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
 201         </para>
 202     </refsect1>
 203 </refentry>