upstream-man-pages/man3/glGetSamplerParameter.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="glGetSamplerParameter">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>2010</year>
   9                 <holder>Khronos Group</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>glGetSamplerParameter</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>glGetSamplerParameter</refname>
  17         <refpurpose>return sampler parameter values</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>void <function>glGetSamplerParameterfv</function></funcdef>
  23                 <paramdef>GLuint <parameter>sampler</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>glGetSamplerParameteriv</function></funcdef>
  31                 <paramdef>GLuint <parameter>sampler</parameter></paramdef>
  32                 <paramdef>GLenum <parameter>pname</parameter></paramdef>
  33                 <paramdef>GLint * <parameter>params</parameter></paramdef>
  34             </funcprototype>
  35         </funcsynopsis>
  36         <funcsynopsis>
  37             <funcprototype>
  38                 <funcdef>void <function>glGetSamplerParameterIiv</function></funcdef>
  39                 <paramdef>GLuint <parameter>sampler</parameter></paramdef>
  40                 <paramdef>GLenum <parameter>pname</parameter></paramdef>
  41                 <paramdef>GLint * <parameter>params</parameter></paramdef>
  42             </funcprototype>
  43         </funcsynopsis>
  44         <funcsynopsis>
  45             <funcprototype>
  46                 <funcdef>void <function>glGetSamplerParameterIuiv</function></funcdef>
  47                 <paramdef>GLuint <parameter>sampler</parameter></paramdef>
  48                 <paramdef>GLenum <parameter>pname</parameter></paramdef>
  49                 <paramdef>GLuint * <parameter>params</parameter></paramdef>
  50             </funcprototype>
  51         </funcsynopsis>
  52     </refsynopsisdiv>
  53     <!-- eqn: ignoring delim $$ -->
  54     <refsect1 id="parameters"><title>Parameters</title>
  55         <variablelist>
  56         <varlistentry>
  57             <term><parameter>sampler</parameter></term>
  58             <listitem>
  59                 <para>
  60                     Specifies name of the sampler object from which to retrieve parameters.
  61                 </para>
  62             </listitem>
  63         </varlistentry>
  64         <varlistentry>
  65             <term><parameter>pname</parameter></term>
  66             <listitem>
  67                 <para>
  68                     Specifies the symbolic name of a sampler parameter.
  69                     <constant>GL_TEXTURE_MAG_FILTER</constant>,
  70                     <constant>GL_TEXTURE_MIN_FILTER</constant>,
  71                     <constant>GL_TEXTURE_MIN_LOD</constant>,
  72                     <constant>GL_TEXTURE_MAX_LOD</constant>,
  73                     <constant>GL_TEXTURE_LOD_BIAS</constant>,
  74                     <constant>GL_TEXTURE_WRAP_S</constant>,
  75                     <constant>GL_TEXTURE_WRAP_T</constant>,
  76                     <constant>GL_TEXTURE_WRAP_R</constant>,
  77                     <constant>GL_TEXTURE_BORDER_COLOR</constant>,
  78                     <constant>GL_TEXTURE_COMPARE_MODE</constant>, and
  79                     <constant>GL_TEXTURE_COMPARE_FUNC</constant>
  80                     are accepted.
  81                 </para>
  82             </listitem>
  83         </varlistentry>
  84         <varlistentry>
  85             <term><parameter>params</parameter></term>
  86             <listitem>
  87                 <para>
  88                     Returns the sampler parameters.
  89                 </para>
  90             </listitem>
  91         </varlistentry>
  92         </variablelist>
  93     </refsect1>
  94     <refsect1 id="description"><title>Description</title>
  95         <para>
  96             <function>glGetSamplerParameter</function> returns in <parameter>params</parameter> the value or values of the sampler parameter
  97             specified as <parameter>pname</parameter>.
  98             <parameter>sampler</parameter> defines the target sampler, and must be the name of an existing sampler object, returned from a previous call
  99             to <citerefentry><refentrytitle>glGenSamplers</refentrytitle></citerefentry>.
 100             <parameter>pname</parameter> accepts the same symbols as <citerefentry><refentrytitle>glSamplerParameter</refentrytitle></citerefentry>,
 101             with the same interpretations:
 102         </para>
 103         <variablelist>
 104             <varlistentry>
 105                 <term><constant>GL_TEXTURE_MAG_FILTER</constant></term>
 106                 <listitem>
 107                     <para>
 108                         Returns the single-valued texture magnification filter,
 109                         a symbolic constant. The initial value is <constant>GL_LINEAR</constant>.
 110                     </para>
 111                 </listitem>
 112             </varlistentry>
 113             <varlistentry>
 114                 <term><constant>GL_TEXTURE_MIN_FILTER</constant></term>
 115                 <listitem>
 116                     <para>
 117                         Returns the single-valued texture minification filter,
 118                         a symbolic constant. The initial value is <constant>GL_NEAREST_MIPMAP_LINEAR</constant>.
 119                     </para>
 120                 </listitem>
 121             </varlistentry>
 122             <varlistentry>
 123                 <term><constant>GL_TEXTURE_MIN_LOD</constant></term>
 124                 <listitem>
 125                     <para>
 126                         Returns the single-valued texture minimum level-of-detail value.  The
 127                         initial value is
 128                         <inlineequation><mml:math>
 129                             <!-- eqn: -1000: -->
 130                             <mml:mn>-1000</mml:mn>
 131                         </mml:math></inlineequation>.
 132                     </para>
 133                 </listitem>
 134             </varlistentry>
 135             <varlistentry>
 136                 <term><constant>GL_TEXTURE_MAX_LOD</constant></term>
 137                 <listitem>
 138                     <para>
 139                         Returns the single-valued texture maximum level-of-detail value. The
 140                         initial value is 1000.
 141                     </para>
 142                 </listitem>
 143             </varlistentry>
 144             <varlistentry>
 145                 <term><constant>GL_TEXTURE_WRAP_S</constant></term>
 146                 <listitem>
 147                     <para>
 148                         Returns the single-valued wrapping function for texture coordinate
 149                         <inlineequation><mml:math><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>,
 150                         a symbolic constant. The initial value is <constant>GL_REPEAT</constant>.
 151                     </para>
 152                 </listitem>
 153             </varlistentry>
 154             <varlistentry>
 155                 <term><constant>GL_TEXTURE_WRAP_T</constant></term>
 156                 <listitem>
 157                     <para>
 158                         Returns the single-valued wrapping function for texture coordinate
 159                         <inlineequation><mml:math><mml:mi mathvariant="italic">t</mml:mi></mml:math></inlineequation>,
 160                         a symbolic constant. The initial value is <constant>GL_REPEAT</constant>.
 161                     </para>
 162                 </listitem>
 163             </varlistentry>
 164             <varlistentry>
 165                 <term><constant>GL_TEXTURE_WRAP_R</constant></term>
 166                 <listitem>
 167                     <para>
 168                         Returns the single-valued wrapping function for texture coordinate
 169                         <inlineequation><mml:math><mml:mi mathvariant="italic">r</mml:mi></mml:math></inlineequation>,
 170                         a symbolic constant. The initial value is <constant>GL_REPEAT</constant>.
 171                     </para>
 172                 </listitem>
 173             </varlistentry>
 174             <varlistentry>
 175                 <term><constant>GL_TEXTURE_BORDER_COLOR</constant></term>
 176                 <listitem>
 177                     <para>
 178                         Returns four integer or floating-point numbers that comprise the RGBA color
 179                         of the texture border.
 180                         Floating-point values are returned in the range
 181                         <inlineequation><mml:math>
 182                             <!-- eqn: [0,1]: -->
 183                             <mml:mfenced open="[" close="]">
 184                                 <mml:mn>0</mml:mn>
 185                                 <mml:mn>1</mml:mn>
 186                             </mml:mfenced>
 187                         </mml:math></inlineequation>.
 188                         Integer values are returned as a linear mapping of the internal floating-point
 189                         representation such that 1.0 maps to the most positive representable
 190                         integer and
 191                         <inlineequation><mml:math>
 192                             <!-- eqn: -1.0: -->
 193                             <mml:mn>-1.0</mml:mn>
 194                         </mml:math></inlineequation>
 195                         maps to the most negative representable
 196                         integer. The initial value is (0, 0, 0, 0).
 197                     </para>
 198                 </listitem>
 199             </varlistentry>
 200             <varlistentry>
 201                 <term><constant>GL_TEXTURE_COMPARE_MODE</constant></term>
 202                 <listitem>
 203                     <para>
 204                         Returns a single-valued texture comparison mode, a symbolic constant.  The
 205                         initial value is <constant>GL_NONE</constant>. See <citerefentry><refentrytitle>glSamplerParameter</refentrytitle></citerefentry>.
 206                     </para>
 207                 </listitem>
 208             </varlistentry>
 209             <varlistentry>
 210                 <term><constant>GL_TEXTURE_COMPARE_FUNC</constant></term>
 211                 <listitem>
 212                     <para>
 213                         Returns a single-valued texture comparison function, a symbolic constant.  The
 214                         initial value is <constant>GL_LEQUAL</constant>. See <citerefentry><refentrytitle>glSamplerParameter</refentrytitle></citerefentry>.
 215                     </para>
 216                 </listitem>
 217             </varlistentry>
 218         </variablelist>
 219     </refsect1>
 220     <refsect1 id="notes"><title>Notes</title>
 221         <para>
 222             If an error is generated,
 223             no change is made to the contents of <parameter>params</parameter>.
 224         </para>
 225         <para>
 226             <function>glGetSamplerParameter</function> is available only if the GL version is 3.3 or higher.
 227         </para>
 228     </refsect1>
 229     <refsect1 id="errors"><title>Errors</title>
 230         <para>
 231             <constant>GL_INVALID_VALUE</constant> is generated if <parameter>sampler</parameter> is not the name of a sampler object returned from
 232             a previous call to <citerefentry><refentrytitle>glGenSamplers</refentrytitle></citerefentry>.
 233         </para>
 234         <para>
 235             <constant>GL_INVALID_ENUM</constant> is generated if <parameter>pname</parameter> is not an accepted value.
 236         </para>
 237     </refsect1>
 238     <refsect1 id="seealso"><title>See Also</title>
 239         <para>
 240             <citerefentry><refentrytitle>glSamplerParameter</refentrytitle></citerefentry>,
 241             <citerefentry><refentrytitle>glGenSamplers</refentrytitle></citerefentry>,
 242             <citerefentry><refentrytitle>glDeleteSamplers</refentrytitle></citerefentry>,
 243             <citerefentry><refentrytitle>glSamplerParameter</refentrytitle></citerefentry>
 244         </para>
 245     </refsect1>
 246     <refsect1 id="Copyright"><title>Copyright</title>
 247         <para>
 248             Copyright <trademark class="copyright"></trademark> 2010 Khronos Group.
 249             This material may be distributed subject to the terms and conditions set forth in
 250             the Open Publication License, v 1.0, 8 June 1999.
 251             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
 252         </para>
 253     </refsect1>
 254 </refentry>