upstream-man-pages/man2/glGetColorTableParameter.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="glGetColorTableParameter">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>1991-2006</year>
   9                 <holder>Silicon Graphics, Inc.</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>glGetColorTableParameter</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>glGetColorTableParameter</refname>
  17         <refpurpose>get color lookup table parameters</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>void <function>glGetColorTableParameterfv</function></funcdef>
  23                 <paramdef>GLenum <parameter>target</parameter></paramdef>
  24                 <paramdef>GLenum <parameter>pname</parameter></paramdef>
  25                 <paramdef>GLfloat * <parameter>params</parameter></paramdef>
  26             </funcprototype>
  27         </funcsynopsis>
  28         <funcsynopsis>
  29             <funcprototype>
  30                 <funcdef>void <function>glGetColorTableParameteriv</function></funcdef>
  31                 <paramdef>GLenum <parameter>target</parameter></paramdef>
  32                 <paramdef>GLenum <parameter>pname</parameter></paramdef>
  33                 <paramdef>GLint * <parameter>params</parameter></paramdef>
  34             </funcprototype>
  35         </funcsynopsis>
  36     </refsynopsisdiv>
  37     <!-- eqn: ignoring delim $$ -->
  38     <refsect1 id="parameters"><title>Parameters</title>
  39         <variablelist>
  40         <varlistentry>
  41             <term><parameter>target</parameter></term>
  42             <listitem>
  43                 <para>
  44                     The target color table.
  45                     Must be
  46                     <constant>GL_COLOR_TABLE</constant>,
  47                     <constant>GL_POST_CONVOLUTION_COLOR_TABLE</constant>,
  48                     <constant>GL_POST_COLOR_MATRIX_COLOR_TABLE</constant>,
  49                     <constant>GL_PROXY_COLOR_TABLE</constant>,
  50                     <constant>GL_PROXY_POST_CONVOLUTION_COLOR_TABLE</constant>, or
  51                     <constant>GL_PROXY_POST_COLOR_MATRIX_COLOR_TABLE</constant>.
  52                 </para>
  53             </listitem>
  54         </varlistentry>
  55         <varlistentry>
  56             <term><parameter>pname</parameter></term>
  57             <listitem>
  58                 <para>
  59                     The symbolic name of a color lookup table parameter.
  60                     Must be one of
  61                     <constant>GL_COLOR_TABLE_BIAS</constant>,
  62                     <constant>GL_COLOR_TABLE_SCALE</constant>,
  63                     <constant>GL_COLOR_TABLE_FORMAT</constant>,
  64                     <constant>GL_COLOR_TABLE_WIDTH</constant>,
  65                     <constant>GL_COLOR_TABLE_RED_SIZE</constant>,
  66                     <constant>GL_COLOR_TABLE_GREEN_SIZE</constant>,
  67                     <constant>GL_COLOR_TABLE_BLUE_SIZE</constant>,
  68                     <constant>GL_COLOR_TABLE_ALPHA_SIZE</constant>,
  69                     <constant>GL_COLOR_TABLE_LUMINANCE_SIZE</constant>, or
  70                     <constant>GL_COLOR_TABLE_INTENSITY_SIZE</constant>.
  71                 </para>
  72             </listitem>
  73         </varlistentry>
  74         <varlistentry>
  75             <term><parameter>params</parameter></term>
  76             <listitem>
  77                 <para>
  78                     A pointer to an array where the values of the parameter will be stored.
  79                 </para>
  80             </listitem>
  81         </varlistentry>
  82         </variablelist>
  83     </refsect1>
  84     <refsect1 id="description"><title>Description</title>
  85         <para>
  86             Returns parameters specific to color table <parameter>target</parameter>.
  87         </para>
  88         <para>
  89             When <parameter>pname</parameter> is set to <constant>GL_COLOR_TABLE_SCALE</constant> or
  90             <constant>GL_COLOR_TABLE_BIAS</constant>, <function>glGetColorTableParameter</function> returns the color
  91             table scale or bias parameters for the table specified by <parameter>target</parameter>.
  92             For these queries, <parameter>target</parameter> must be set to
  93             <constant>GL_COLOR_TABLE</constant>,
  94             <constant>GL_POST_CONVOLUTION_COLOR_TABLE</constant>,
  95             or <constant>GL_POST_COLOR_MATRIX_COLOR_TABLE</constant> and
  96             <parameter>params</parameter> points to an array of four elements, which receive
  97             the scale or bias factors for red, green, blue, and alpha, in that order.
  98         </para>
  99         <para>
 100             <function>glGetColorTableParameter</function> can also be used to retrieve the format and size parameters
 101             for a color table. For these queries, set <parameter>target</parameter> to either the
 102             color table target or the proxy color table target.
 103             The format and size parameters are set by <citerefentry><refentrytitle>glColorTable</refentrytitle></citerefentry>.
 104         </para>
 105         <para>
 106             The following table lists the format and size parameters that may
 107             be queried.
 108             For each symbolic constant listed below for <parameter>pname</parameter>,
 109             <parameter>params</parameter> must point to an array of the
 110             given length and receive the values indicated.
 111         </para>
 112         <para>
 113         </para>
 114         <informaltable frame="topbot">
 115             <tgroup cols="3" align="left">
 116                 <colspec colwidth="4*" />
 117                 <colspec colwidth="1*" align="center"/>
 118                 <colspec colwidth="3*" />
 119                 <thead>
 120                     <row>
 121                         <entry rowsep="1" align="left"><emphasis role="bold">
 122                         Parameter
 123                         </emphasis></entry>
 124                         <entry rowsep="1" align="center"><emphasis role="bold">
 125                         N
 126                         </emphasis></entry>
 127                         <entry rowsep="1" align="left"><emphasis role="bold">
 128                         Meaning
 129                         </emphasis></entry>
 130                     </row>
 131                 </thead>
 132                 <tbody>
 133                     <row>
 134                         <entry align="left">
 135                         <constant>GL_COLOR_TABLE_FORMAT</constant>
 136                         </entry>
 137                         <entry align="center">
 138                         1
 139                         </entry>
 140                         <entry align="left">
 141                         Internal format (e.g., <constant>GL_RGBA</constant>)
 142                         </entry>
 143                     </row>
 144                     <row>
 145                         <entry align="left">
 146                         <constant>GL_COLOR_TABLE_WIDTH</constant>
 147                         </entry>
 148                         <entry align="center">
 149                         1
 150                         </entry>
 151                         <entry align="left">
 152                         Number of elements in table
 153                         </entry>
 154                     </row>
 155                     <row>
 156                         <entry align="left">
 157                         <constant>GL_COLOR_TABLE_RED_SIZE</constant>
 158                         </entry>
 159                         <entry align="center">
 160                         1
 161                         </entry>
 162                         <entry align="left">
 163                         Size of red component, in bits
 164                         </entry>
 165                     </row>
 166                     <row>
 167                         <entry align="left">
 168                         <constant>GL_COLOR_TABLE_GREEN_SIZE</constant>
 169                         </entry>
 170                         <entry align="center">
 171                         1
 172                         </entry>
 173                         <entry align="left">
 174                         Size of green component
 175                         </entry>
 176                     </row>
 177                     <row>
 178                         <entry align="left">
 179                         <constant>GL_COLOR_TABLE_BLUE_SIZE</constant>
 180                         </entry>
 181                         <entry align="center">
 182                         1
 183                         </entry>
 184                         <entry align="left">
 185                         Size of blue component
 186                         </entry>
 187                     </row>
 188                     <row>
 189                         <entry align="left">
 190                         <constant>GL_COLOR_TABLE_ALPHA_SIZE</constant>
 191                         </entry>
 192                         <entry align="center">
 193                         1
 194                         </entry>
 195                         <entry align="left">
 196                         Size of alpha component
 197                         </entry>
 198                     </row>
 199                     <row>
 200                         <entry align="left">
 201                         <constant>GL_COLOR_TABLE_LUMINANCE_SIZE</constant>
 202                         </entry>
 203                         <entry align="center">
 204                         1
 205                         </entry>
 206                         <entry align="left">
 207                         Size of luminance component
 208                         </entry>
 209                     </row>
 210                     <row>
 211                         <entry align="left">
 212                         <constant>GL_COLOR_TABLE_INTENSITY_SIZE</constant>
 213                         </entry>
 214                         <entry align="center">
 215                         1
 216                         </entry>
 217                         <entry align="left">
 218                         Size of intensity component
 219                         </entry>
 220                     </row>
 221                 </tbody>
 222             </tgroup>
 223         </informaltable>
 224         <para>
 225         </para>
 226     </refsect1>
 227     <refsect1 id="notes"><title>Notes</title>
 228         <para>
 229             <function>glGetColorTableParameter</function> is present only if <code>ARB_imaging</code> is returned when <citerefentry><refentrytitle>glGetString</refentrytitle></citerefentry>
 230             is called with an argument of <constant>GL_EXTENSIONS</constant>.
 231         </para>
 232     </refsect1>
 233     <refsect1 id="errors"><title>Errors</title>
 234         <para>
 235             <constant>GL_INVALID_ENUM</constant> is generated if <parameter>target</parameter> or <parameter>pname</parameter> is not
 236             an acceptable value.
 237         </para>
 238         <para>
 239             <constant>GL_INVALID_OPERATION</constant> is generated if <function>glGetColorTableParameter</function> is executed
 240             between the execution of <citerefentry><refentrytitle>glBegin</refentrytitle></citerefentry> and the corresponding
 241             execution of <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
 242         </para>
 243     </refsect1>
 244     <refsect1 id="seealso"><title>See Also</title>
 245         <para>
 246             <citerefentry><refentrytitle>glColorTable</refentrytitle></citerefentry>,
 247             <citerefentry><refentrytitle>glTexParameter</refentrytitle></citerefentry>,
 248             <citerefentry><refentrytitle>glColorTableParameter</refentrytitle></citerefentry>
 249         </para>
 250     </refsect1>
 251     <refsect1 id="Copyright"><title>Copyright</title>
 252         <para>
 253             Copyright <trademark class="copyright"></trademark> 1991-2006
 254             Silicon Graphics, Inc. This document is licensed under the SGI
 255             Free Software B License. For details, see
 256             <ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>.
 257         </para>
 258     </refsect1>
 259 </refentry>