upstream-man-pages/manglsl/gl_PointCoord.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="gl_PointCoord">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>2011</year>
   9                 <holder>Khronos Group</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>gl_PointCoord</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>gl_PointCoord</refname>
  17         <refpurpose>contains the coordinate of a fragment within a point</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>Declaration</title>
  20         <funcsynopsis>
  21             <function>in vec2 gl_PointCoord;</function>
  22         </funcsynopsis>
  23     </refsynopsisdiv>
  24     <refsect1 id="description"><title>Description</title>
  25         <para>
  26             <function>gl_PointCoord</function> is a fragment language input variable that contains
  27             the two-dimensional coordinates indicating where within a point primitive the current
  28             fragment is located. If the current primitive is not a point, then values read
  29             from <function>gl_PointCoord</function> are undefined.
  30         </para>
  31         <para>
  32             <function>gl_PointCoord.s</function> ranges from 0.0 to 1.0 across the point horizontally
  33             from left to right. If <constant>GL_POINT_SPRITE_COORD_ORIGIN</constant> is
  34             <constant>GL_LOWER_LEFT</constant>, <function>gl_PointCoord.t</function> varies
  35             from 0.0 to 1.0 vertically from bottom to top. Otherwise, if <constant>GL_POINT_SPRITE_COORD_ORIGIN</constant>
  36             is <constant>GL_UPPER_LEFT</constant> then <function>gl_PointCoord.t</function> varies
  37             from 0.0 to 1.0 vertically from top to bottom. The default value of <constant>GL_POINT_SPRITE_COORD_ORIGIN</constant>
  38             is <constant>GL_UPPER_LEFT</constant>.
  39         </para>
  40     </refsect1>
  41     <refsect1 id="versions"><title>Version Support</title>
  42         <informaltable frame="topbot">
  43             <tgroup cols="3" align="left">
  44                 <colspec colwidth="1.1*" />
  45                 <colspec colwidth="1*" align="center" />
  46                 <colspec colwidth="1*" align="center" />
  47                 <colspec colwidth="1*" align="center" />
  48                 <colspec colwidth="1*" align="center" />
  49                 <colspec colwidth="1*" align="center" />
  50                 <colspec colwidth="1*" align="center" />
  51                 <colspec colwidth="1*" align="center" />
  52                 <colspec colwidth="1*" align="center" />
  53                 <thead>
  54                     <row>
  55                         <entry rowsep="1" align="left"><emphasis role="bold">
  56                         Variable
  57                         </emphasis></entry>
  58                         <entry rowsep="1" align="left"><emphasis role="bold">
  59                         Version 1.10
  60                         </emphasis></entry>
  61                         <entry rowsep="1" align="left"><emphasis role="bold">
  62                         Version 1.20
  63                         </emphasis></entry>
  64                         <entry rowsep="1" align="left"><emphasis role="bold">
  65                         Version 1.30
  66                         </emphasis></entry>
  67                         <entry rowsep="1" align="left"><emphasis role="bold">
  68                         Version 1.40
  69                         </emphasis></entry>
  70                         <entry rowsep="1" align="left"><emphasis role="bold">
  71                         Version 1.50
  72                         </emphasis></entry>
  73                         <entry rowsep="1" align="left"><emphasis role="bold">
  74                         Version 3.30
  75                         </emphasis></entry>
  76                         <entry rowsep="1" align="left"><emphasis role="bold">
  77                         Version 4.00
  78                         </emphasis></entry>
  79                         <entry rowsep="1" align="left"><emphasis role="bold">
  80                         Version 4.10
  81                         </emphasis></entry>
  82                     </row>
  83                     <row>
  84                         <entry>
  85                             gl_PointCoord
  86                         </entry>
  87                         <entry>
  88                             <emphasis>Y</emphasis>
  89                         </entry>
  90                         <entry>
  91                             <emphasis>Y</emphasis>
  92                         </entry>
  93                         <entry>
  94                             <emphasis>Y</emphasis>
  95                         </entry>
  96                         <entry>
  97                             <emphasis>Y</emphasis>
  98                         </entry>
  99                         <entry>
 100                             <emphasis>Y</emphasis>
 101                         </entry>
 102                         <entry>
 103                             <emphasis>Y</emphasis>
 104                         </entry>
 105                         <entry>
 106                             <emphasis>Y</emphasis>
 107                         </entry>
 108                         <entry>
 109                             <emphasis>Y</emphasis>
 110                         </entry>
 111                     </row>
 112                 </thead>
 113             </tgroup>
 114         </informaltable>
 115     </refsect1>
 116     <refsect1 id="seealso"><title>See Also</title>
 117         <para>
 118             <citerefentry><refentrytitle>gl_FragCoord</refentrytitle></citerefentry>,
 119             <citerefentry><refentrytitle>gl_FragDepth</refentrytitle></citerefentry>
 120         </para>
 121     </refsect1>
 122     <refsect1 id="Copyright"><title>Copyright</title>
 123         <para>
 124             Copyright <trademark class="copyright"></trademark> 2011 Khronos Group.
 125             This material may be distributed subject to the terms and conditions set forth in
 126             the Open Publication License, v 1.0, 8 June 1999.
 127             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
 128         </para>
 129     </refsect1>
 130 </refentry>