upstream-man-pages/man4/xhtml/glGetShaderPrecisionFormat.xml

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   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>glGetShaderPrecisionFormat - OpenGL 4 Reference Pages</title><meta name="generator" content="DocBook XSL Stylesheets V1.69.1" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="glGetShaderPrecisionFormat"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glGetShaderPrecisionFormat — retrieve the range and precision for numeric formats supported by the shader compiler</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glGetShaderPrecisionFormat</b>(</code></td><td>GLenum  </td><td><var class="pdparam">shaderType</var>, </td></tr><tr><td> </td><td>GLenum  </td><td><var class="pdparam">precisionType</var>, </td></tr><tr><td> </td><td>GLint * </td><td><var class="pdparam">range</var>, </td></tr><tr><td> </td><td>GLint * </td><td><var class="pdparam">precision</var><code>)</code>;</td></tr></table></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>shaderType</code></em></span></dt><dd><p>
   5                 Specifies the type of shader whose precision to query. <em class="parameter"><code>shaderType</code></em>
   6                 must be <code class="constant">GL_VERTEX_SHADER</code> or <code class="constant">GL_FRAGMENT_SHADER</code>.
   7             </p></dd><dt><span class="term"><em class="parameter"><code>precisionType</code></em></span></dt><dd><p>
   8                 Specifies the numeric format whose precision and range to query.
   9             </p></dd><dt><span class="term"><em class="parameter"><code>range</code></em></span></dt><dd><p>
  10                 Specifies the address of array of two integers into which encodings of the implementation's
  11                 numeric range are returned.
  12             </p></dd><dt><span class="term"><em class="parameter"><code>precision</code></em></span></dt><dd><p>
  13                 Specifies the address of an integer into which the numeric precision of the implementation
  14                 is written.
  15             </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
  16             <code class="function">glGetShaderPrecisionFormat</code> retrieves the numeric range and precision for
  17             the implementation's representation of quantities in different numeric formats in specified
  18             shader type. <em class="parameter"><code>shaderType</code></em> specifies the type of shader for which the numeric
  19             precision and range is to be retrieved and must be one of <code class="constant">GL_VERTEX_SHADER</code>
  20             or <code class="constant">GL_FRAGMENT_SHADER</code>. <em class="parameter"><code>precisionType</code></em> specifies the
  21             numeric format to query and must be one of <code class="constant">GL_LOW_FLOAT</code>, <code class="constant">GL_MEDIUM_FLOAT</code>
  22             <code class="constant">GL_HIGH_FLOAT</code>, <code class="constant">GL_LOW_INT</code>, <code class="constant">GL_MEDIUM_INT</code>,
  23             or <code class="constant">GL_HIGH_INT</code>.
  24         </p><p>
  25             <em class="parameter"><code>range</code></em> points to an array of two integers into which the format's numeric range
  26             will be returned. If min and max are the smallest values representable in the format, then the values
  27             returned are defined to be: <em class="parameter"><code>range</code></em>[0] = floor(log2(|min|)) and
  28             <em class="parameter"><code>range</code></em>[1] = floor(log2(|max|)).
  29         </p><p>
  30             <em class="parameter"><code>precision</code></em> specifies the address of an integer into which will be written
  31             the log2 value of the number of bits of precision of the format. If the smallest representable
  32             value greater than 1 is 1 + <span class="emphasis"><em>eps</em></span>, then the integer addressed by <em class="parameter"><code>precision</code></em>
  33             will contain floor(-log2(eps)).
  34         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
  35             <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>shaderType</code></em> or
  36             <em class="parameter"><code>precisionType</code></em> is not an accepted value.
  37         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
  38             Copyright <span class="trademark"></span>© 2010 Khronos Group.
  39             This material may be distributed subject to the terms and conditions set forth in
  40             the Open Publication License, v 1.0, 8 June 1999.
  41             <a href="http://opencontent.org/openpub/" target="_top">http://opencontent.org/openpub/</a>.
  42         </p></div></div></body></html>