upstream-man-pages/man2/xhtml/glPointParameter.xml

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   3 <?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" /><title>glPointParameter</title><meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="glPointParameter"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glPointParameter — specify point parameters</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">glPointParameterf</b>(</code></td><td>GLenum  </td><td><var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>GLfloat  </td><td><var class="pdparam">param</var><code>)</code>;</td></tr></table></div><p></p><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glPointParameteri</b>(</code></td><td>GLenum  </td><td><var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>GLint  </td><td><var class="pdparam">param</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>pname</code></em></span></dt><dd><p>
   4                     Specifies a single-valued point parameter.
   5                     <code class="constant">GL_POINT_SIZE_MIN</code>,
   6                     <code class="constant">GL_POINT_SIZE_MAX</code>,
   7                     <code class="constant">GL_POINT_FADE_THRESHOLD_SIZE</code>, and
   8                     <code class="constant">GL_POINT_SPRITE_COORD_ORIGIN</code>
   9                     are accepted.
  10                 </p></dd><dt><span class="term"><em class="parameter"><code>param</code></em></span></dt><dd><p>
  11                     Specifies the value that <em class="parameter"><code>pname</code></em> will be set to.
  12                 </p></dd></dl></div></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">glPointParameterfv</b>(</code></td><td>GLenum  </td><td><var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>const GLfloat *  </td><td><var class="pdparam">params</var><code>)</code>;</td></tr></table></div><p></p><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glPointParameteriv</b>(</code></td><td>GLenum  </td><td><var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>const GLint *  </td><td><var class="pdparam">params</var><code>)</code>;</td></tr></table></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="parameters2"></a><h2>Parameters</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>pname</code></em></span></dt><dd><p>
  13                     Specifies a point parameter.
  14                     <code class="constant">GL_POINT_SIZE_MIN</code>,
  15                     <code class="constant">GL_POINT_SIZE_MAX</code>,
  16                     <code class="constant">GL_POINT_DISTANCE_ATTENUATION</code>,
  17                     <code class="constant">GL_POINT_FADE_THRESHOLD_SIZE</code>, and
  18                     <code class="constant">GL_POINT_SPRITE_COORD_ORIGIN</code>
  19                     are accepted.
  20                 </p></dd><dt><span class="term"><em class="parameter"><code>params</code></em></span></dt><dd><p>
  21                     Specifies the value or values to be assigned to <em class="parameter"><code>pname</code></em>.
  22                     <code class="constant">GL_POINT_DISTANCE_ATTENUATION</code> requires an array of three values.
  23                     All other parameters accept an array containing only a single value.
  24                 </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
  25             The following values are accepted for <em class="parameter"><code>pname</code></em>:
  26         </p><div class="variablelist"><dl><dt><span class="term"><code class="constant">GL_POINT_SIZE_MIN</code></span></dt><dd><p>
  27                     </p><p>
  28                         <em class="parameter"><code>params</code></em> is a single floating-point value that specifies the minimum point size.  The default value is 0.0.
  29                     </p></dd><dt><span class="term"><code class="constant">GL_POINT_SIZE_MAX</code></span></dt><dd><p>
  30                     </p><p>
  31                         <em class="parameter"><code>params</code></em> is a single floating-point value that specifies the maximum point size.  The default value is 1.0.
  32                     </p></dd><dt><span class="term"><code class="constant">GL_POINT_FADE_THRESHOLD_SIZE</code></span></dt><dd><p>
  33                     </p><p>
  34                         <em class="parameter"><code>params</code></em> is a single floating-point value that specifies the threshold value
  35                         to which point sizes are clamped if they exceed the specified value.  The
  36                         default value is 1.0.
  37                     </p></dd><dt><span class="term"><code class="constant">GL_POINT_DISTANCE_ATTENUATION</code></span></dt><dd><p>
  38                     </p><p>
  39                         <em class="parameter"><code>params</code></em> is an array of three floating-point values that specify the
  40                         coefficients used for scaling the computed point size.  The default values
  41                         are
  42                         <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  43
  44                             <mml:mfenced open="(" close=")">
  45                                 <mml:mn>1</mml:mn>
  46                                 <mml:mn>0</mml:mn>
  47                                 <mml:mn>0</mml:mn>
  48                             </mml:mfenced>
  49                         </mml:math>.
  50                     </p></dd><dt><span class="term"><code class="constant">GL_POINT_SPRITE_COORD_ORIGIN</code></span></dt><dd><p>
  51                     </p><p>
  52                         <em class="parameter"><code>params</code></em> is a single enum specifying the point sprite texture coordinate origin, either <code class="constant">GL_LOWER_LEFT</code> or <code class="constant">GL_UPPER_LEFT</code>.
  53                         The default value is <code class="constant">GL_UPPER_LEFT</code>.
  54                     </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
  55             <code class="function">glPointParameter</code> is available only if the GL version is 1.4 or greater.
  56         </p><p>
  57             <code class="constant">GL_POINT_SPRITE_COORD_ORIGIN</code> is available only if the GL version is 2.0 or greater.
  58         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
  59             <code class="constant">GL_INVALID_VALUE</code> is generated If the value specified for
  60             <code class="constant">GL_POINT_SIZE_MIN</code>, <code class="constant">GL_POINT_SIZE_MAX</code>, or
  61             <code class="constant">GL_POINT_FADE_THRESHOLD_SIZE</code> is less than zero.
  62         </p><p>
  63             <code class="constant">GL_INVALID_ENUM</code> is generated If the value specified for
  64             <code class="constant">GL_POINT_SPRITE_COORD_ORIGIN</code> is not <code class="constant">GL_LOWER_LEFT</code> or <code class="constant">GL_UPPER_LEFT</code>.
  65         </p><p>
  66             If the value for <code class="constant">GL_POINT_SIZE_MIN</code> is greater than
  67             <code class="constant">GL_POINT_SIZE_MAX</code>, the point size after clamping is undefined, but no
  68             error is generated.
  69         </p><p>
  70         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
  71             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_POINT_SIZE_MIN</code>
  72         </p><p>
  73             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_POINT_SIZE_MAX</code>
  74         </p><p>
  75             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_POINT_FADE_THRESHOLD_SIZE</code>
  76         </p><p>
  77             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_POINT_DISTANCE_ATTENUATION</code>
  78         </p><p>
  79             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_POINT_SPRITE_COORD_ORIGIN</code>
  80         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
  81             <a class="citerefentry" href="glPointSize.xml"><span class="citerefentry"><span class="refentrytitle">glPointSize</span></span></a>
  82         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
  83             Copyright <span class="trademark"></span>© 1991-2006
  84             Silicon Graphics, Inc. This document is licensed under the SGI
  85             Free Software B License. For details, see
  86             <a class="ulink" href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
  87         </p></div></div></body></html>