upstream-man-pages/man2/xhtml/glXGetFBConfigAttrib.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>glXGetFBConfigAttrib</title><meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="glXGetFBConfigAttrib"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glXGetFBConfigAttrib — return information about a GLX frame buffer configuration</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">int <b class="fsfunc">glXGetFBConfigAttrib</b>(</code></td><td>Display *  </td><td><var class="pdparam">dpy</var>, </td></tr><tr><td> </td><td>GLXFBConfig  </td><td><var class="pdparam">config</var>, </td></tr><tr><td> </td><td>int  </td><td><var class="pdparam">attribute</var>, </td></tr><tr><td> </td><td>int *  </td><td><var class="pdparam">value</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>dpy</code></em></span></dt><dd><p>
   4                     Specifies the connection to the X server.
   5                 </p></dd><dt><span class="term"><em class="parameter"><code>config</code></em></span></dt><dd><p>
   6                     Specifies the GLX frame buffer configuration to be queried.
   7                 </p></dd><dt><span class="term"><em class="parameter"><code>attribute</code></em></span></dt><dd><p>
   8                     Specifies the attribute to be returned.
   9                 </p></dd><dt><span class="term"><em class="parameter"><code>value</code></em></span></dt><dd><p>
  10                     Returns the requested value.
  11                 </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
  12             <code class="function">glXGetFBConfigAttrib</code> sets <em class="parameter"><code>value</code></em> to the <em class="parameter"><code>attribute</code></em> value of GLX drawables
  13             created with respect to <em class="parameter"><code>config</code></em>.
  14             <code class="function">glXGetFBConfigAttrib</code> returns an error code if it fails for any reason.
  15             Otherwise, <code class="constant">Success</code> is returned.
  16         </p><p>
  17             <em class="parameter"><code>attribute</code></em> is one of the following:
  18         </p><p>
  19         </p><div class="variablelist"><dl><dt><span class="term"><code class="constant">GLX_FBCONFIG_ID</code></span></dt><dd><p>
  20                         XID of the given GLXFBConfig.
  21                     </p></dd><dt><span class="term"><code class="constant">GLX_BUFFER_SIZE</code></span></dt><dd><p>
  22                     </p><p>
  23                         Number of bits per color buffer.
  24                         If the frame buffer configuration supports RGBA contexts, then
  25                         <code class="constant">GLX_BUFFER_SIZE</code> is the sum of
  26                         <code class="constant">GLX_RED_SIZE</code>,
  27                         <code class="constant">GLX_GREEN_SIZE</code>,
  28                         <code class="constant">GLX_BLUE_SIZE</code>, and
  29                         <code class="constant">GLX_ALPHA_SIZE</code>.
  30                         If the frame buffer configuration supports only color index contexts,
  31                         <code class="constant">GLX_BUFFER_SIZE</code> is the size of the
  32                         color indexes.
  33                     </p></dd><dt><span class="term"><code class="constant">GLX_LEVEL</code></span></dt><dd><p>
  34                     </p><p>
  35                         Frame buffer level of the configuration.
  36                         Level zero is the default frame buffer.
  37                         Positive levels correspond to frame buffers that overlay the default buffer,
  38                         and negative levels correspond to frame buffers that underlie the default
  39                         buffer.
  40                     </p></dd><dt><span class="term"><code class="constant">GLX_DOUBLEBUFFER</code></span></dt><dd><p>
  41                     </p><p>
  42                         <code class="constant">True</code> if color buffers exist in front/back pairs that can be swapped,
  43                         <code class="constant">False</code> otherwise.
  44                     </p></dd><dt><span class="term"><code class="constant">GLX_STEREO</code></span></dt><dd><p>
  45                     </p><p>
  46                         <code class="constant">True</code> if color buffers exist in left/right pairs,
  47                         <code class="constant">False</code> otherwise.
  48                     </p></dd><dt><span class="term"><code class="constant">GLX_AUX_BUFFERS</code></span></dt><dd><p>
  49                     </p><p>
  50                         Number of auxiliary color buffers that are available.
  51                         Zero indicates that no auxiliary color buffers exist.
  52                     </p></dd><dt><span class="term"><code class="constant">GLX_RED_SIZE</code></span></dt><dd><p>
  53                     </p><p>
  54                         Number of bits of red stored in each color buffer.
  55                         Undefined if RGBA contexts are not supported by the frame buffer configuration.
  56                     </p></dd><dt><span class="term"><code class="constant">GLX_GREEN_SIZE</code></span></dt><dd><p>
  57                     </p><p>
  58                         Number of bits of green stored in each color buffer.
  59                         Undefined if RGBA contexts are not supported by the frame buffer configuration.
  60                     </p></dd><dt><span class="term"><code class="constant">GLX_BLUE_SIZE</code></span></dt><dd><p>
  61                     </p><p>
  62                         Number of bits of blue stored in each color buffer.
  63                         Undefined if RGBA contexts are not supported by the frame buffer configuration.
  64                     </p></dd><dt><span class="term"><code class="constant">GLX_ALPHA_SIZE</code></span></dt><dd><p>
  65                     </p><p>
  66                         Number of bits of alpha stored in each color buffer.
  67                         Undefined if RGBA contexts are not supported by the frame buffer configuration.
  68                     </p></dd><dt><span class="term"><code class="constant">GLX_DEPTH_SIZE</code></span></dt><dd><p>
  69                     </p><p>
  70                         Number of bits in the depth buffer.
  71                     </p></dd><dt><span class="term"><code class="constant">GLX_STENCIL_SIZE</code></span></dt><dd><p>
  72                     </p><p>
  73                         Number of bits in the stencil buffer.
  74                     </p></dd><dt><span class="term"><code class="constant">GLX_ACCUM_RED_SIZE</code></span></dt><dd><p>
  75                     </p><p>
  76                         Number of bits of red stored in the accumulation buffer.
  77                     </p></dd><dt><span class="term"><code class="constant">GLX_ACCUM_GREEN_SIZE</code></span></dt><dd><p>
  78                     </p><p>
  79                         Number of bits of green stored in the accumulation buffer.
  80                     </p></dd><dt><span class="term"><code class="constant">GLX_ACCUM_BLUE_SIZE</code></span></dt><dd><p>
  81                     </p><p>
  82                         Number of bits of blue stored in the accumulation buffer.
  83                     </p></dd><dt><span class="term"><code class="constant">GLX_ACCUM_ALPHA_SIZE</code></span></dt><dd><p>
  84                     </p><p>
  85                         Number of bits of alpha stored in the accumulation buffer.
  86                     </p></dd><dt><span class="term"><code class="constant">GLX_RENDER_TYPE</code></span></dt><dd><p>
  87                     </p><p>
  88                         Mask indicating what type of GLX contexts can be made
  89                         current to the frame buffer configuration. Valid bits are
  90                         <code class="constant">GLX_RGBA_BIT</code> and
  91                         <code class="constant">GLX_COLOR_INDEX_BIT</code>.
  92                     </p></dd><dt><span class="term"><code class="constant">GLX_DRAWABLE_TYPE</code></span></dt><dd><p>
  93                     </p><p>
  94                         Mask indicating what drawable types the frame buffer configuration
  95                         supports. Valid bits are <code class="constant">GLX_WINDOW_BIT</code>,
  96                         <code class="constant">GLX_PIXMAP_BIT</code>, and <code class="constant">GLX_PBUFFER_BIT</code>.
  97                     </p></dd><dt><span class="term"><code class="constant">GLX_X_RENDERABLE</code></span></dt><dd><p>
  98                     </p><p>
  99                         <code class="constant">True</code> if drawables created with the
 100                         frame buffer configuration can be rendered to by X.
 101                     </p></dd><dt><span class="term"><code class="constant">GLX_VISUAL_ID</code></span></dt><dd><p>
 102                     </p><p>
 103                         XID of the corresponding visual, or zero
 104                         if there is no associated visual (i.e., if
 105                         <code class="constant">GLX_X_RENDERABLE</code> is <code class="constant">False</code> or
 106                         <code class="constant">GLX_DRAWABLE_TYPE</code> does not have the
 107                         <code class="constant">GLX_WINDOW_BIT</code> bit set).
 108                     </p></dd><dt><span class="term"><code class="constant">GLX_X_VISUAL_TYPE</code></span></dt><dd><p>
 109                     </p><p>
 110                         Visual type of associated visual. The returned value will be one of:
 111                         <code class="constant">GLX_TRUE_COLOR</code>, <code class="constant">GLX_DIRECT_COLOR</code>, <code class="constant">GLX_PSEUDO_COLOR</code>,
 112                         <code class="constant">GLX_STATIC_COLOR</code>, <code class="constant">GLX_GRAY_SCALE</code>, <code class="constant">GLX_STATIC_GRAY</code>,
 113                         or <code class="constant">GLX_NONE</code>, if there is no associated visual (i.e., if
 114                         <code class="constant">GLX_X_RENDERABLE</code> is <code class="constant">False</code> or
 115                         <code class="constant">GLX_DRAWABLE_TYPE</code> does not have the
 116                         <code class="constant">GLX_WINDOW_BIT</code> bit set).
 117                     </p></dd><dt><span class="term"><code class="constant">GLX_CONFIG_CAVEAT</code></span></dt><dd><p>
 118                     </p><p>
 119                         One of <code class="constant">GLX_NONE</code>,
 120                         <code class="constant">GLX_SLOW_CONFIG</code>, or
 121                         <code class="constant">GLX_NON_CONFORMANT_CONFIG</code>, indicating
 122                         that the frame buffer configuration has no caveats,
 123                         some aspect of the frame buffer configuration runs slower
 124                         than other frame buffer configurations, or some aspect of the
 125                         frame buffer configuration is nonconformant, respectively.
 126                     </p></dd><dt><span class="term"><code class="constant">GLX_TRANSPARENT_TYPE</code></span></dt><dd><p>
 127                     </p><p>
 128                         One of <code class="constant">GLX_NONE</code>,
 129                         <code class="constant">GLX_TRANSPARENT_RGB</code>,
 130                         <code class="constant">GLX_TRANSPARENT_INDEX</code>, indicating that
 131                         the frame buffer configuration is opaque, is transparent for particular
 132                         values of red, green, and blue, or is transparent for
 133                         particular index values, respectively.
 134                     </p></dd><dt><span class="term"><code class="constant">GLX_TRANSPARENT_INDEX_VALUE</code></span></dt><dd><p>
 135                     </p><p>
 136                         Integer value between 0 and the maximum
 137                         frame buffer value for indices, indicating the transparent
 138                         index value for the frame buffer configuration.
 139                         Undefined if <code class="constant">GLX_TRANSPARENT_TYPE</code>
 140                         is not <code class="constant">GLX_TRANSPARENT_INDEX</code>.
 141                     </p></dd><dt><span class="term"><code class="constant">GLX_TRANSPARENT_RED_VALUE</code></span></dt><dd><p>
 142                     </p><p>
 143                         Integer value between 0 and the maximum
 144                         frame buffer value for red, indicating the transparent
 145                         red value for the frame buffer configuration.
 146                         Undefined if <code class="constant">GLX_TRANSPARENT_TYPE</code>
 147                         is not <code class="constant">GLX_TRANSPARENT_RGB</code>.
 148                     </p></dd><dt><span class="term"><code class="constant">GLX_TRANSPARENT_GREEN_VALUE</code></span></dt><dd><p>
 149                     </p><p>
 150                         Integer value between 0 and the maximum
 151                         frame buffer value for green, indicating the transparent
 152                         green value for the frame buffer configuration.
 153                         Undefined if <code class="constant">GLX_TRANSPARENT_TYPE</code>
 154                         is not <code class="constant">GLX_TRANSPARENT_RGB</code>.
 155                     </p></dd><dt><span class="term"><code class="constant">GLX_TRANSPARENT_BLUE_VALUE</code></span></dt><dd><p>
 156                     </p><p>
 157                         Integer value between 0 and the maximum
 158                         frame buffer value for blue, indicating the transparent
 159                         blue value for the frame buffer configuration.
 160                         Undefined if <code class="constant">GLX_TRANSPARENT_TYPE</code>
 161                         is not <code class="constant">GLX_TRANSPARENT_RGB</code>.
 162                     </p></dd><dt><span class="term"><code class="constant">GLX_TRANSPARENT_ALPHA_VALUE</code></span></dt><dd><p>
 163                     </p><p>
 164                         Integer value between 0 and the maximum
 165                         frame buffer value for alpha, indicating the transparent
 166                         blue value for the frame buffer configuration.
 167                         Undefined if <code class="constant">GLX_TRANSPARENT_TYPE</code>
 168                         is not <code class="constant">GLX_TRANSPARENT_RGB</code>.
 169                     </p></dd><dt><span class="term"><code class="constant">GLX_MAX_PBUFFER_WIDTH</code></span></dt><dd><p>
 170                     </p><p>
 171                         The maximum width that can be specified to
 172                         <a class="citerefentry" href="glXCreatePbuffer.xml"><span class="citerefentry"><span class="refentrytitle">glXCreatePbuffer</span></span></a>.
 173                     </p></dd><dt><span class="term"><code class="constant">GLX_MAX_PBUFFER_HEIGHT</code></span></dt><dd><p>
 174                     </p><p>
 175                         The maximum height that can be specified to
 176                         <a class="citerefentry" href="glXCreatePbuffer.xml"><span class="citerefentry"><span class="refentrytitle">glXCreatePbuffer</span></span></a>.
 177                     </p></dd><dt><span class="term"><code class="constant">GLX_MAX_PBUFFER_PIXELS</code></span></dt><dd><p>
 178                     </p><p>
 179                         The maximum number of pixels (width times height) for a
 180                         pixel buffer. Note that this value may be less than
 181                         <code class="constant">GLX_MAX_PBUFFER_WIDTH</code> times
 182                         <code class="constant">GLX_MAX_PBUFFER_HEIGHT</code>. Also, this
 183                         value is static and assumes that no other pixel buffers
 184                         or X resources are contending for the frame buffer memory.
 185                         As a result, it may not be possible to allocate a pixel buffer of
 186                         the size given by <code class="constant">GLX_MAX_PBUFFER_PIXELS</code>.
 187                     </p></dd></dl></div><p>
 188             Applications should choose the frame buffer configuration that most closely
 189             meets their requirements.
 190             Creating windows, GLX pixmaps, or GLX pixel buffers with unnecessary buffers
 191             can result in
 192             reduced rendering performance as well as poor resource allocation.
 193         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
 194             <code class="function">glXGetFBConfigAttrib</code> is available only if the GLX version is 1.3 or greater.
 195         </p><p>
 196             If the GLX version is 1.1 or 1.0, the GL version must be 1.0.
 197             If the GLX version is 1.2, then the GL version must be 1.1.
 198             If the GLX version is 1.3, then the GL version must be 1.2.
 199         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
 200             <code class="constant">GLX_NO_EXTENSION</code> is returned if <em class="parameter"><code>dpy</code></em> does not support the GLX
 201             extension.
 202             <code class="constant">GLX_BAD_ATTRIBUTE</code> is returned if <em class="parameter"><code>attribute</code></em> is not a valid GLX attribute.
 203         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
 204             <a class="citerefentry" href="glXGetFBConfigs.xml"><span class="citerefentry"><span class="refentrytitle">glXGetFBConfigs</span></span></a>,
 205             <a class="citerefentry" href="glXChooseFBConfig.xml"><span class="citerefentry"><span class="refentrytitle">glXChooseFBConfig</span></span></a>,
 206             <a class="citerefentry" href="glXGetVisualFromFBConfig.xml"><span class="citerefentry"><span class="refentrytitle">glXGetVisualFromFBConfig</span></span></a>,
 207             <a class="citerefentry" href="glXGetConfig.xml"><span class="citerefentry"><span class="refentrytitle">glXGetConfig</span></span></a>
 208         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
 209             Copyright <span class="trademark"></span>© 1991-2006
 210             Silicon Graphics, Inc. This document is licensed under the SGI
 211             Free Software B License. For details, see
 212             <a class="ulink" href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
 213         </p></div></div></body></html>