+++ /dev/null
-<?xml version="1.0" encoding="UTF-8"?>\r
-<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"\r
- "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">\r
-<refentry id="textureGather">\r
- <refmeta>\r
- <refmetainfo>\r
- <copyright>\r
- <year>2011</year>\r
- <holder>Khronos Group</holder>\r
- </copyright>\r
- </refmetainfo>\r
- <refentrytitle>textureGather</refentrytitle>\r
- <manvolnum>3G</manvolnum>\r
- </refmeta>\r
- <refnamediv>\r
- <refname>textureGather</refname>\r
- <refpurpose>gathers four texels from a texture</refpurpose>\r
- </refnamediv>\r
- <refsynopsisdiv><title>Declaration</title>\r
- <funcsynopsis>\r
- <funcprototype>\r
- <funcdef>gvec4 <function>textureGather</function></funcdef>\r
- <paramdef>gsampler2D <parameter>sampler</parameter></paramdef>\r
- <paramdef>vec2 <parameter>P</parameter></paramdef>\r
- <paramdef>[int <parameter>comp]</parameter></paramdef>\r
- </funcprototype>\r
- <funcprototype>\r
- <funcdef>gvec4 <function>textureGather</function></funcdef>\r
- <paramdef>gsampler2DArray <parameter>sampler</parameter></paramdef>\r
- <paramdef>vec3 <parameter>P</parameter></paramdef>\r
- <paramdef>[int <parameter>comp]</parameter></paramdef>\r
- </funcprototype>\r
- <funcprototype>\r
- <funcdef>gvec4 <function>textureGather</function></funcdef>\r
- <paramdef>gsamplerCube <parameter>sampler</parameter></paramdef>\r
- <paramdef>vec3 <parameter>P</parameter></paramdef>\r
- <paramdef>[int <parameter>comp]</parameter></paramdef>\r
- </funcprototype>\r
- <funcprototype>\r
- <funcdef>gvec4 <function>textureGather</function></funcdef>\r
- <paramdef>gsamplerCubeArray <parameter>sampler</parameter></paramdef>\r
- <paramdef>vec4 <parameter>P</parameter></paramdef>\r
- <paramdef>[int <parameter>comp]</parameter></paramdef>\r
- </funcprototype>\r
- <funcprototype>\r
- <funcdef>gvec4 <function>textureGather</function></funcdef>\r
- <paramdef>gsampler2DRect <parameter>sampler</parameter></paramdef>\r
- <paramdef>vec3 <parameter>P</parameter></paramdef>\r
- <paramdef>[int <parameter>comp]</parameter></paramdef>\r
- </funcprototype>\r
- <funcprototype>\r
- <funcdef>vec4 <function>textureGather</function></funcdef>\r
- <paramdef>gsampler2DShadow <parameter>sampler</parameter></paramdef>\r
- <paramdef>vec2 <parameter>P</parameter></paramdef>\r
- <paramdef>float <parameter>refZ</parameter></paramdef>\r
- </funcprototype>\r
- <funcprototype>\r
- <funcdef>vec4 <function>textureGather</function></funcdef>\r
- <paramdef>gsampler2DArrayShadow <parameter>sampler</parameter></paramdef>\r
- <paramdef>vec3 <parameter>P</parameter></paramdef>\r
- <paramdef>float <parameter>refZ</parameter></paramdef>\r
- </funcprototype>\r
- <funcprototype>\r
- <funcdef>vec4 <function>textureGather</function></funcdef>\r
- <paramdef>gsamplerCubeShadow <parameter>sampler</parameter></paramdef>\r
- <paramdef>vec3 <parameter>P</parameter></paramdef>\r
- <paramdef>float <parameter>refZ</parameter></paramdef>\r
- </funcprototype>\r
- <funcprototype>\r
- <funcdef>vec4 <function>textureGather</function></funcdef>\r
- <paramdef>gsamplerCubeArrayShadow <parameter>sampler</parameter></paramdef>\r
- <paramdef>vec4 <parameter>P</parameter></paramdef>\r
- <paramdef>float <parameter>refZ</parameter></paramdef>\r
- </funcprototype>\r
- <funcprototype>\r
- <funcdef>vec4 <function>textureGather</function></funcdef>\r
- <paramdef>gsampler2DRectShadow <parameter>sampler</parameter></paramdef>\r
- <paramdef>vec3 <parameter>P</parameter></paramdef>\r
- <paramdef>float <parameter>refZ</parameter></paramdef>\r
- </funcprototype>\r
- </funcsynopsis>\r
- </refsynopsisdiv>\r
- <refsect1 id="parameters"><title>Parameters</title>\r
- <variablelist>\r
- <varlistentry>\r
- <term><parameter>sampler</parameter></term>\r
- <listitem>\r
- <para>\r
- Specifies the sampler to which the texture from which texels will be retrieved is bound.\r
- </para>\r
- </listitem>\r
- </varlistentry>\r
- <varlistentry>\r
- <term><parameter>P</parameter></term>\r
- <listitem>\r
- <para>\r
- Specifies the texture coordinates at which texture will be sampled.\r
- </para>\r
- </listitem>\r
- </varlistentry>\r
- <varlistentry>\r
- <term><parameter>comp</parameter></term>\r
- <listitem>\r
- <para>\r
- Specifies the component of the source texture that will be used to generate the resulting vector.\r
- </para>\r
- </listitem>\r
- </varlistentry>\r
- <varlistentry>\r
- <term><parameter>refZ</parameter></term>\r
- <listitem>\r
- <para>\r
- Specifies the reference Z value used in the comparison for shadow forms.\r
- </para>\r
- </listitem>\r
- </varlistentry>\r
- </variablelist>\r
- </refsect1>\r
- <refsect1 id="description"><title>Description</title>\r
- <para>\r
- <function>textureGather</function> returns the value:\r
- </para>\r
- <para>\r
-<programlisting><![CDATA[ vec4(Sample_i0_j1(P, base).comp,\r
- Sample_i1_j1(P, base).comp,\r
- Sample_i1_j0(P, base).comp,\r
- Sample_i0_j9(P, base).comp);]]></programlisting>\r
- </para>\r
- <para>\r
- If specified, the value of <parameter>comp</parameter> must ba constant integer expression with a value\r
- of 0, 1, 2, or 3, identifying the x, y, z or w component of the four-component vector lookup result for each\r
- texel, respectively. If <parameter>comp</parameter> is not specified, it is treated as 0, selecting the x\r
- component of each texel to generate the result.\r
- </para>\r
- </refsect1>\r
- <refsect1 id="versions"><title>Version Support</title>\r
- <informaltable frame="topbot">\r
- #VARTABLECOLS#\r
- <thead>\r
- #FUNCTABLEHEADER#\r
- <row>\r
- <entry>textureGather</entry>#newin40#\r
- </row>\r
- </thead>\r
- </tgroup>\r
- </informaltable>\r
- </refsect1>\r
- <refsect1 id="seealso"><title>See Also</title>\r
- <para>\r
- <citerefentry><refentrytitle>texelFetch</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>texelFetchOffset</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>texture</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureGatherOffset</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureGatherOffsets</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureGrad</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureGradOffset</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureLod</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureLodOffset</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureOffset</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureProj</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureProjGrad</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureProjGradOffset</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureProjLod</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureProjLodOffset</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureProjOffset</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureQueryLod</refentrytitle></citerefentry>,\r
- <citerefentry><refentrytitle>textureSize</refentrytitle></citerefentry>\r
- </para>\r
- </refsect1>\r
- <refsect1 id="Copyright"><title>Copyright</title>\r
- <para>\r
- Copyright <trademark class="copyright"></trademark> 2011 Khronos Group. \r
- This material may be distributed subject to the terms and conditions set forth in \r
- the Open Publication License, v 1.0, 8 June 1999.\r
- <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.\r
- </para>\r
- </refsect1>\r
-</refentry>\r