upstream-man-pages/man2/xhtml/glWindowPos.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>glWindowPos</title><meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="glWindowPos"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glWindowPos — specify the raster position in window coordinates for pixel operations</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">glWindowPos2s</b>(</code></td><td>GLshort  </td><td><var class="pdparam">x</var>, </td></tr><tr><td> </td><td>GLshort  </td><td><var class="pdparam">y</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glWindowPos2i</b>(</code></td><td>GLint  </td><td><var class="pdparam">x</var>, </td></tr><tr><td> </td><td>GLint  </td><td><var class="pdparam">y</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glWindowPos2f</b>(</code></td><td>GLfloat  </td><td><var class="pdparam">x</var>, </td></tr><tr><td> </td><td>GLfloat  </td><td><var class="pdparam">y</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glWindowPos2d</b>(</code></td><td>GLdouble  </td><td><var class="pdparam">x</var>, </td></tr><tr><td> </td><td>GLdouble  </td><td><var class="pdparam">y</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glWindowPos3s</b>(</code></td><td>GLshort  </td><td><var class="pdparam">x</var>, </td></tr><tr><td> </td><td>GLshort  </td><td><var class="pdparam">y</var>, </td></tr><tr><td> </td><td>GLshort  </td><td><var class="pdparam">z</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glWindowPos3i</b>(</code></td><td>GLint  </td><td><var class="pdparam">x</var>, </td></tr><tr><td> </td><td>GLint  </td><td><var class="pdparam">y</var>, </td></tr><tr><td> </td><td>GLint  </td><td><var class="pdparam">z</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glWindowPos3f</b>(</code></td><td>GLfloat  </td><td><var class="pdparam">x</var>, </td></tr><tr><td> </td><td>GLfloat  </td><td><var class="pdparam">y</var>, </td></tr><tr><td> </td><td>GLfloat  </td><td><var class="pdparam">z</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glWindowPos3d</b>(</code></td><td>GLdouble  </td><td><var class="pdparam">x</var>, </td></tr><tr><td> </td><td>GLdouble  </td><td><var class="pdparam">y</var>, </td></tr><tr><td> </td><td>GLdouble  </td><td><var class="pdparam">z</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>x</code></em>, </span><span class="term"><em class="parameter"><code>y</code></em>, </span><span class="term"><em class="parameter"><code>z</code></em></span></dt><dd><p>
   4                     Specify the
   5                     <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">x</mml:mi></mml:math>,
   6                     <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">y</mml:mi></mml:math>,
   7                     <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">z</mml:mi></mml:math>
   8                     coordinates for the raster position.
   9                 </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">glWindowPos2sv</b>(</code></td><td>const GLshort *  </td><td><var class="pdparam">v</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glWindowPos2iv</b>(</code></td><td>const GLint *  </td><td><var class="pdparam">v</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glWindowPos2fv</b>(</code></td><td>const GLfloat *  </td><td><var class="pdparam">v</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glWindowPos2dv</b>(</code></td><td>const GLdouble *  </td><td><var class="pdparam">v</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glWindowPos3sv</b>(</code></td><td>const GLshort *  </td><td><var class="pdparam">v</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glWindowPos3iv</b>(</code></td><td>const GLint *  </td><td><var class="pdparam">v</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glWindowPos3fv</b>(</code></td><td>const GLfloat *  </td><td><var class="pdparam">v</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glWindowPos3dv</b>(</code></td><td>const GLdouble *  </td><td><var class="pdparam">v</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>v</code></em></span></dt><dd><p>
  10                     Specifies a pointer to an array of two or three elements,
  11                     specifying
  12                     <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">x</mml:mi></mml:math>,
  13                     <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">y</mml:mi></mml:math>,
  14                     <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">z</mml:mi></mml:math>
  15                     coordinates, respectively.
  16                 </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
  17             The GL maintains a 3D position in window coordinates.  This position,
  18             called the raster position, is used to position pixel and bitmap write
  19             operations. It is maintained with subpixel accuracy.  See <a class="citerefentry" href="glBitmap.xml"><span class="citerefentry"><span class="refentrytitle">glBitmap</span></span></a>,
  20             <a class="citerefentry" href="glDrawPixels.xml"><span class="citerefentry"><span class="refentrytitle">glDrawPixels</span></span></a>, and <a class="citerefentry" href="glCopyPixels.xml"><span class="citerefentry"><span class="refentrytitle">glCopyPixels</span></span></a>.
  21         </p><p>
  22             <code class="function">glWindowPos2</code> specifies the
  23             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">x</mml:mi></mml:math>
  24             and
  25             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">y</mml:mi></mml:math>
  26             coordinates, while
  27             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">z</mml:mi></mml:math>
  28             is
  29             implicitly set to 0.  <code class="function">glWindowPos3</code> specifies all three coordinates.
  30             The
  31             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">w</mml:mi></mml:math>
  32             coordinate of the current raster position is always set to 1.0.
  33         </p><p>
  34             <code class="function">glWindowPos</code> directly updates the
  35             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">x</mml:mi></mml:math>
  36             and
  37             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">y</mml:mi></mml:math>
  38             coordinates of the current raster
  39             position with the values specified.  That is, the values are neither
  40             transformed by the current modelview and projection matrices, nor by
  41             the viewport-to-window transform.  The
  42             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">z</mml:mi></mml:math>
  43             coordinate of the current raster
  44             position is updated in the following manner:
  45         </p><p>
  46             </p><div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  47
  48                 <mml:mrow>
  49                     <mml:mi mathvariant="italic">z</mml:mi>
  50                     <mml:mo>=</mml:mo>
  51                     <mml:mfenced open="{" close="">
  52                         <mml:mrow>
  53                             <mml:mtable>
  54                                 <mml:mtr><mml:mtd>
  55                                     <mml:mi mathvariant="italic">n</mml:mi>
  56                                 </mml:mtd></mml:mtr>
  57                                 <mml:mtr><mml:mtd>
  58                                     <mml:mi mathvariant="italic">f</mml:mi>
  59                                 </mml:mtd></mml:mtr>
  60                                 <mml:mtr><mml:mtd>
  61                                     <mml:mfenced open="" close="">
  62                                         <mml:mrow>
  63                                             <mml:mi mathvariant="italic">n</mml:mi>
  64                                             <mml:mo>+</mml:mo>
  65                                             <mml:mrow>
  66                                                 <mml:mi mathvariant="italic">z</mml:mi>
  67                                                 <mml:mo>×</mml:mo>
  68                                                 <mml:mfenced open="(" close=")">
  69                                                     <mml:mrow>
  70                                                         <mml:mi mathvariant="italic">f</mml:mi>
  71                                                         <mml:mo>-</mml:mo>
  72                                                         <mml:mi mathvariant="italic">n</mml:mi>
  73                                                     </mml:mrow>
  74                                                 </mml:mfenced>
  75                                             </mml:mrow>
  76                                         </mml:mrow>
  77                                     </mml:mfenced>
  78                                 </mml:mtd></mml:mtr>
  79                             </mml:mtable>
  80                             <mml:mo>⁢</mml:mo>
  81                             <mml:mtable>
  82                                 <mml:mtr><mml:mtd>
  83                                     <mml:mrow>
  84                                         <mml:mrow>
  85                                             <mml:mi mathvariant="italic">if</mml:mi>
  86                                             <mml:mo>⁢</mml:mo>
  87                                             <mml:mi mathvariant="italic">z</mml:mi>
  88                                         </mml:mrow>
  89                                         <mml:mo>&lt;=</mml:mo>
  90                                         <mml:mn>0</mml:mn>
  91                                     </mml:mrow>
  92                                 </mml:mtd></mml:mtr>
  93                                 <mml:mtr><mml:mtd>
  94                                     <mml:mrow>
  95                                         <mml:mrow>
  96                                             <mml:mi mathvariant="italic">if</mml:mi>
  97                                             <mml:mo>⁢</mml:mo>
  98                                             <mml:mi mathvariant="italic">z</mml:mi>
  99                                         </mml:mrow>
 100                                         <mml:mo>&gt;=</mml:mo>
 101                                         <mml:mn>1</mml:mn>
 102                                     </mml:mrow>
 103                                 </mml:mtd></mml:mtr>
 104                                 <mml:mtr><mml:mtd>
 105                                     <mml:mfenced open="" close="">
 106                                         <mml:mi mathvariant="normal">otherwise</mml:mi>
 107                                     </mml:mfenced>
 108                                 </mml:mtd></mml:mtr>
 109                             </mml:mtable>
 110                         </mml:mrow>
 111                     </mml:mfenced>
 112                 </mml:mrow>
 113             </mml:math></div><p>
 114         </p><p>
 115         </p><p>
 116             where
 117             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">n</mml:mi></mml:math>
 118             is <code class="constant">GL_DEPTH_RANGE</code>'s near value, and
 119             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">f</mml:mi></mml:math>
 120             is
 121             <code class="constant">GL_DEPTH_RANGE</code>'s far value.  See <a class="citerefentry" href="glDepthRange.xml"><span class="citerefentry"><span class="refentrytitle">glDepthRange</span></span></a>.
 122         </p><p>
 123             The specified coordinates are not clip-tested, causing the raster position
 124             to always be valid.
 125         </p><p>
 126             The current raster position also includes some associated color data and
 127             texture coordinates.  If lighting is enabled, then
 128             <code class="constant">GL_CURRENT_RASTER_COLOR</code> (in RGBA mode) or <code class="constant">GL_CURRENT_RASTER_INDEX</code>
 129             (in color index mode) is set to the color produced by the lighting
 130             calculation (see <a class="citerefentry" href="glLight.xml"><span class="citerefentry"><span class="refentrytitle">glLight</span></span></a>, <a class="citerefentry" href="glLightModel.xml"><span class="citerefentry"><span class="refentrytitle">glLightModel</span></span></a>, and <a class="citerefentry" href="glShadeModel.xml"><span class="citerefentry"><span class="refentrytitle">glShadeModel</span></span></a>).
 131             If lighting is disabled, current color (in RGBA mode, state variable
 132             <code class="constant">GL_CURRENT_COLOR</code>) or color index (in color index mode, state variable
 133             <code class="constant">GL_CURRENT_INDEX</code>) is used to update the current raster color.
 134             <code class="constant">GL_CURRENT_RASTER_SECONDARY_COLOR</code> (in RGBA mode) is likewise updated.
 135         </p><p>
 136             Likewise, <code class="constant">GL_CURRENT_RASTER_TEXTURE_COORDS</code> is updated as a function of
 137             <code class="constant">GL_CURRENT_TEXTURE_COORDS</code>, based on the texture matrix and the texture
 138             generation functions (see <a class="citerefentry" href="glTexGen.xml"><span class="citerefentry"><span class="refentrytitle">glTexGen</span></span></a>).  The
 139             <code class="constant">GL_CURRENT_RASTER_DISTANCE</code> is set to the <code class="constant">GL_CURRENT_FOG_COORD</code>.
 140         </p><p>
 141         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
 142             <code class="function">glWindowPos</code> is available only if the GL version is 1.4 or greater.
 143         </p><p>
 144             The raster position is modified by <a class="citerefentry" href="glRasterPos.xml"><span class="citerefentry"><span class="refentrytitle">glRasterPos</span></span></a>, <a class="citerefentry" href="glBitmap.xml"><span class="citerefentry"><span class="refentrytitle">glBitmap</span></span></a>, and
 145             <code class="function">glWindowPos</code>.
 146         </p><p>
 147             Calling <a class="citerefentry" href="glDrawElements.xml"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>, or <a class="citerefentry" href="glDrawRangeElements.xml"><span class="citerefentry"><span class="refentrytitle">glDrawRangeElements</span></span></a> may leave the
 148             current color or index indeterminate.
 149             If <code class="function">glWindowPos</code> is executed while the current color or index is indeterminate, the
 150             current raster color or current raster index remains indeterminate.
 151         </p><p>
 152             There are distinct raster texture coordinates for each texture unit. Each
 153             texture unit's current raster texture coordinates are updated by <code class="function">glWindowPos</code>.
 154         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
 155             <code class="constant">GL_INVALID_OPERATION</code> is generated if <code class="function">glWindowPos</code>
 156             is executed between the execution of <a class="citerefentry" href="glBegin.xml"><span class="citerefentry"><span class="refentrytitle">glBegin</span></span></a>
 157             and the corresponding execution of <a class="citerefentry" href="glEnd.xml"><span class="citerefentry"><span class="refentrytitle">glEnd</span></span></a>.
 158         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
 159             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_CURRENT_RASTER_POSITION</code>
 160         </p><p>
 161             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_CURRENT_RASTER_POSITION_VALID</code>
 162         </p><p>
 163             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_CURRENT_RASTER_DISTANCE</code>
 164         </p><p>
 165             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_CURRENT_RASTER_COLOR</code>
 166         </p><p>
 167             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_CURRENT_RASTER_SECONDARY_COLOR</code>
 168         </p><p>
 169             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_CURRENT_RASTER_INDEX</code>
 170         </p><p>
 171             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_CURRENT_RASTER_TEXTURE_COORDS</code>
 172         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
 173             <a class="citerefentry" href="glBitmap.xml"><span class="citerefentry"><span class="refentrytitle">glBitmap</span></span></a>,
 174             <a class="citerefentry" href="glCopyPixels.xml"><span class="citerefentry"><span class="refentrytitle">glCopyPixels</span></span></a>,
 175             <a class="citerefentry" href="glDrawArrays.xml"><span class="citerefentry"><span class="refentrytitle">glDrawArrays</span></span></a>,
 176             <a class="citerefentry" href="glDrawElements.xml"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>,
 177             <a class="citerefentry" href="glDrawRangeElements.xml"><span class="citerefentry"><span class="refentrytitle">glDrawRangeElements</span></span></a>,
 178             <a class="citerefentry" href="glDrawPixels.xml"><span class="citerefentry"><span class="refentrytitle">glDrawPixels</span></span></a>,
 179             <a class="citerefentry" href="glMultiTexCoord.xml"><span class="citerefentry"><span class="refentrytitle">glMultiTexCoord</span></span></a>,
 180             <a class="citerefentry" href="glRasterPos.xml"><span class="citerefentry"><span class="refentrytitle">glRasterPos</span></span></a>,
 181             <a class="citerefentry" href="glTexCoord.xml"><span class="citerefentry"><span class="refentrytitle">glTexCoord</span></span></a>,
 182             <a class="citerefentry" href="glTexGen.xml"><span class="citerefentry"><span class="refentrytitle">glTexGen</span></span></a>,
 183             <a class="citerefentry" href="glVertex.xml"><span class="citerefentry"><span class="refentrytitle">glVertex</span></span></a>
 184         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
 185             Copyright <span class="trademark"></span>© 1991-2006
 186             Silicon Graphics, Inc. This document is licensed under the SGI
 187             Free Software B License. For details, see
 188             <a class="ulink" href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
 189         </p></div></div></body></html>