upstream-man-pages/manglsl/xhtml/fwidth.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "xhtml1-transitional.dtd">
   3 <!-- saved from url=(0013)about:internet -->
   4 <?xml-stylesheet type="text/xsl" href="mathml.xsl"?><html xmlns="http://www.w3.org/1999/xhtml" xmlns:pref="http://www.w3.org/2002/Math/preference" pref:renderer="mathplayer-dl"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><link rel="stylesheet" type="text/css" href="opengl-man.css" /><title>fwidth - OpenGL Shading Language (GLSL)</title><meta name="generator" content="DocBook XSL Stylesheets V1.69.1" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="fwidth"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>fwidth — return the sum of the absolute derivatives in x and y</p></div><div class="refsynopsisdiv"><h2>Declaration</h2><div class="funcsynopsis"><p><code class="funcdef">genType <b class="fsfunc">fwidth</b>(</code>genType <var class="pdparam">p</var><code>)</code>;</p></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>p</code></em></span></dt><dd><p>
   5                     Specifies the expression of which to take the partial derivative.
   6                 </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
   7             <span class="emphasis"><em>Available only in the fragment shader</em></span>, <code class="function">fwidth</code> returns the sum of
   8             the absolute derivatives in x and y using local differencing for the input argument <em class="parameter"><code>p</code></em>.
   9             It is equivalent to <code class="code"><a href="abs.xml"><span class="citerefentry"><span class="refentrytitle">abs</span></span></a>(<a href="dFdx.xml"><span class="citerefentry"><span class="refentrytitle">dFdx</span></span></a>(p)) + <a href="abs.xml"><span class="citerefentry"><span class="refentrytitle">abs</span></span></a>(<a href="dFdy.xml"><span class="citerefentry"><span class="refentrytitle">dFdy</span></span></a>(p))</code>.
  10         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="versions"></a><h2>Version Support</h2><div class="informaltable"><table border="1"><colgroup><col align="left" /><col align="center" /><col align="center" /><col align="center" /><col align="center" /><col align="center" /><col align="center" /><col align="center" /><col align="center" /><col align="center" /><col align="center" /></colgroup><thead><tr><th align="left"><span class="bold"><strong>Function</strong></span></th><th align="left"><span class="bold"><strong>Version 1.10</strong></span></th><th align="left"><span class="bold"><strong>Version 1.20</strong></span></th><th align="left"><span class="bold"><strong>Version 1.30</strong></span></th><th align="left"><span class="bold"><strong>Version 1.40</strong></span></th><th align="left"><span class="bold"><strong>Version 1.50</strong></span></th><th align="left"><span class="bold"><strong>Version 3.30</strong></span></th><th align="left"><span class="bold"><strong>Version 4.00</strong></span></th><th align="left"><span class="bold"><strong>Version 4.10</strong></span></th><th align="left"><span class="bold"><strong>Version 4.20</strong></span></th><th align="center"><span class="bold"><strong>Version 4.30</strong></span></th></tr><tr><th align="left">fwidth</th><th align="center"><span class="emphasis"><em>Y</em></span></th><th align="center"><span class="emphasis"><em>Y</em></span></th><th align="center"><span class="emphasis"><em>Y</em></span></th><th align="center"><span class="emphasis"><em>Y</em></span></th><th align="center"><span class="emphasis"><em>Y</em></span></th><th align="center"><span class="emphasis"><em>Y</em></span></th><th align="center"><span class="emphasis"><em>Y</em></span></th><th align="center"><span class="emphasis"><em>Y</em></span></th><th align="center"><span class="emphasis"><em>Y</em></span></th><th align="center"><span class="emphasis"><em>Y</em></span></th></tr></thead></table></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
  11             <a href="dFdx.xml"><span class="citerefentry"><span class="refentrytitle">dFdx</span></span></a>,
  12             <a href="dFdy.xml"><span class="citerefentry"><span class="refentrytitle">dFdy</span></span></a>
  13         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
  14             Copyright <span class="trademark"></span>© 2011 Khronos Group.
  15             This material may be distributed subject to the terms and conditions set forth in
  16             the Open Publication License, v 1.0, 8 June 1999.
  17             <a href="http://opencontent.org/openpub/" target="_top">http://opencontent.org/openpub/</a>.
  18         </p></div></div></body></html>