upstream-man-pages/manglsl/step.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="step">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>2011</year>
   9                 <holder>Khronos Group</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>step</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>step</refname>
  17         <refpurpose>generate a step function by comparing two values</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>Declaration</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>genType <function>step</function></funcdef>
  23                 <paramdef>genType <parameter>edge</parameter></paramdef>
  24                 <paramdef>genType <parameter>x</parameter></paramdef>
  25             </funcprototype>
  26         </funcsynopsis>
  27         <funcsynopsis>
  28             <funcprototype>
  29                 <funcdef>genType <function>step</function></funcdef>
  30                 <paramdef>float <parameter>edge</parameter></paramdef>
  31                 <paramdef>genType <parameter>x</parameter></paramdef>
  32             </funcprototype>
  33         </funcsynopsis>
  34         <funcsynopsis>
  35             <funcprototype>
  36                 <funcdef>genDType <function>step</function></funcdef>
  37                 <paramdef>genDType <parameter>edge</parameter></paramdef>
  38                 <paramdef>genDType <parameter>x</parameter></paramdef>
  39             </funcprototype>
  40         </funcsynopsis>
  41         <funcsynopsis>
  42             <funcprototype>
  43                 <funcdef>genDType <function>step</function></funcdef>
  44                 <paramdef>double <parameter>edge</parameter></paramdef>
  45                 <paramdef>genDType <parameter>x</parameter></paramdef>
  46             </funcprototype>
  47         </funcsynopsis>
  48     </refsynopsisdiv>
  49     <refsect1 id="parameters"><title>Parameters</title>
  50         <variablelist>
  51         <varlistentry>
  52             <term><parameter>edge</parameter></term>
  53             <listitem>
  54                 <para>
  55                     Specifies the location of the edge of the step function.
  56                 </para>
  57             </listitem>
  58         </varlistentry>
  59         <varlistentry>
  60             <term><parameter>x</parameter></term>
  61             <listitem>
  62                 <para>
  63                     Specify the value to be used to generate the step function.
  64                 </para>
  65             </listitem>
  66         </varlistentry>
  67         </variablelist>
  68     </refsect1>
  69     <refsect1 id="description"><title>Description</title>
  70         <para>
  71             <function>step</function> generates a step function by comparing <parameter>x</parameter> to <parameter>edge</parameter>.
  72         </para>
  73         <para>
  74             For element <emphasis>i</emphasis> of the return value, 0.0 is returned if <parameter>x</parameter>[<emphasis>i</emphasis>]
  75             &lt; <parameter>edge</parameter>[<emphasis>i</emphasis>], and 1.0 is returned otherwise.
  76         </para>
  77     </refsect1>
  78     <refsect1 id="versions"><title>Version Support</title>
  79         <informaltable frame="topbot">
  80             #VARTABLECOLS#
  81                 <thead>
  82                     #FUNCTABLEHEADER#
  83                     <row>
  84                         <entry>step (genType)</entry>#newin11#
  85                     </row>
  86                     <row>
  87                         <entry>step (genDType)</entry>#newin40#
  88                     </row>
  89                 </thead>
  90             </tgroup>
  91         </informaltable>
  92     </refsect1>
  93     <refsect1 id="seealso"><title>See Also</title>
  94         <para>
  95             <citerefentry><refentrytitle>mix</refentrytitle></citerefentry>,
  96             <citerefentry><refentrytitle>smoothstep</refentrytitle></citerefentry>
  97         </para>
  98     </refsect1>
  99     <refsect1 id="Copyright"><title>Copyright</title>
 100         <para>
 101             Copyright <trademark class="copyright"></trademark> 2011 Khronos Group.
 102             This material may be distributed subject to the terms and conditions set forth in
 103             the Open Publication License, v 1.0, 8 June 1999.
 104             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
 105         </para>
 106     </refsect1>
 107 </refentry>