upstream-doc/man3/xhtml/glCopyTexSubImage2D.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
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   4 <?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" /><link rel="stylesheet" type="text/css" href="opengl-man.css" /><title>glCopyTexSubImage2D - OpenGL 3.3 Reference Pages</title><meta name="generator" content="DocBook XSL Stylesheets V1.69.1" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="glCopyTexSubImage2D"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glCopyTexSubImage2D — copy a two-dimensional texture subimage</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">glCopyTexSubImage2D</b>(</code></td><td>GLenum  </td><td><var class="pdparam">target</var>, </td></tr><tr><td> </td><td>GLint  </td><td><var class="pdparam">level</var>, </td></tr><tr><td> </td><td>GLint  </td><td><var class="pdparam">xoffset</var>, </td></tr><tr><td> </td><td>GLint  </td><td><var class="pdparam">yoffset</var>, </td></tr><tr><td> </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>GLsizei  </td><td><var class="pdparam">width</var>, </td></tr><tr><td> </td><td>GLsizei  </td><td><var class="pdparam">height</var><code>)</code>;</td></tr></table></div></div><p>
   5     </p><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>target</code></em></span></dt><dd><p>
   6                     Specifies the target texture.
   7                     Must be <code class="constant">GL_TEXTURE_2D</code>,
   8                     <code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_X</code>,
   9                     <code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_X</code>,
  10                     <code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_Y</code>,
  11                     <code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_Y</code>,
  12                     <code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_Z</code>, or
  13                     <code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_Z</code>.
  14                 </p></dd><dt><span class="term"><em class="parameter"><code>level</code></em></span></dt><dd><p>
  15                     Specifies the level-of-detail number.
  16                     Level 0 is the base image level.
  17                     Level <span class="emphasis"><em>n</em></span> is the <span class="emphasis"><em>n</em></span>th mipmap reduction image.
  18                 </p></dd><dt><span class="term"><em class="parameter"><code>xoffset</code></em></span></dt><dd><p>
  19                     Specifies a texel offset in the x direction within the texture array.
  20                 </p></dd><dt><span class="term"><em class="parameter"><code>yoffset</code></em></span></dt><dd><p>
  21                     Specifies a texel offset in the y direction within the texture array.
  22                 </p></dd><dt><span class="term"><em class="parameter"><code>x</code></em>, </span><span class="term"><em class="parameter"><code>y</code></em></span></dt><dd><p>
  23                     Specify the window coordinates of the lower left corner
  24                     of the rectangular region of pixels to be copied.
  25                 </p></dd><dt><span class="term"><em class="parameter"><code>width</code></em></span></dt><dd><p>
  26                     Specifies the width of the texture subimage.
  27                 </p></dd><dt><span class="term"><em class="parameter"><code>height</code></em></span></dt><dd><p>
  28                     Specifies the height of the texture subimage.
  29                 </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
  30             <code class="function">glCopyTexSubImage2D</code> replaces a rectangular portion of a two-dimensional texture image or
  31             cube-map texture image with pixels from the current <code class="constant">GL_READ_BUFFER</code>
  32             (rather than from main memory, as is the case for <a href="glTexSubImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage2D</span></span></a>).
  33         </p><p>
  34             The screen-aligned pixel rectangle with lower left corner at
  35             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  36
  37                 <mml:mfenced open="(" close=")">
  38                     <mml:mi mathvariant="italic">x</mml:mi>
  39                     <mml:mi mathvariant="italic">y</mml:mi>
  40                 </mml:mfenced>
  41             </mml:math>
  42             and with
  43             width <em class="parameter"><code>width</code></em> and height <em class="parameter"><code>height</code></em> replaces the portion of the
  44             texture array with x indices <em class="parameter"><code>xoffset</code></em> through
  45             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  46
  47                 <mml:mrow>
  48                     <mml:mi mathvariant="italic">xoffset</mml:mi>
  49                     <mml:mo>+</mml:mo>
  50                     <mml:mi mathvariant="italic">width</mml:mi>
  51                     <mml:mo>-</mml:mo>
  52                     <mml:mn>1</mml:mn>
  53                 </mml:mrow>
  54             </mml:math>,
  55             inclusive, and y indices <em class="parameter"><code>yoffset</code></em> through
  56             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  57
  58                 <mml:mrow>
  59                     <mml:mi mathvariant="italic">yoffset</mml:mi>
  60                     <mml:mo>+</mml:mo>
  61                     <mml:mi mathvariant="italic">height</mml:mi>
  62                     <mml:mo>-</mml:mo>
  63                     <mml:mn>1</mml:mn>
  64                 </mml:mrow>
  65             </mml:math>,
  66             inclusive, at the mipmap level specified by <em class="parameter"><code>level</code></em>.
  67         </p><p>
  68             The pixels in the rectangle are processed exactly as if
  69             <a href="glReadPixels.xml"><span class="citerefentry"><span class="refentrytitle">glReadPixels</span></span></a> had been called, but the process stops just before
  70             final conversion.
  71             At this point, all pixel component values are clamped to the range
  72             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  73
  74                 <mml:mfenced open="[" close="]">
  75                     <mml:mn>0</mml:mn>
  76                     <mml:mn>1</mml:mn>
  77                 </mml:mfenced>
  78             </mml:math>
  79             and then converted to the texture's internal format for storage in the texel
  80             array.
  81         </p><p>
  82             The destination rectangle in the texture array may not include any texels
  83             outside the texture array as it was originally specified.
  84             It is not an error to specify a subtexture with zero width or height, but
  85             such a specification has no effect.
  86         </p><p>
  87             If any of the pixels within the specified rectangle of the current
  88             <code class="constant">GL_READ_BUFFER</code> are outside the read window associated with the current
  89             rendering context, then the values obtained for those pixels are undefined.
  90         </p><p>
  91             No change is made to the <span class="emphasis"><em>internalformat</em></span>, <span class="emphasis"><em>width</em></span> or
  92             <span class="emphasis"><em>height</em></span> parameters of the specified texture
  93             array or to texel values outside the specified subregion.
  94         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
  95             <a href="glPixelStore.xml"><span class="citerefentry"><span class="refentrytitle">glPixelStore</span></span></a> modes affect texture images.
  96         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
  97             <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>target</code></em> is not <code class="constant">GL_TEXTURE_2D</code>,
  98             <code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_X</code>,
  99             <code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_X</code>,
 100             <code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_Y</code>,
 101             <code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_Y</code>,
 102             <code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_Z</code>,
 103             <code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_Z</code>, or
 104             <code class="constant">GL_TEXTURE_1D_ARRAY</code>.
 105         </p><p>
 106             <code class="constant">GL_INVALID_OPERATION</code> is generated if the texture array has not been
 107             defined by a previous <a href="glTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage2D</span></span></a> or <a href="glCopyTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage2D</span></span></a> operation.
 108         </p><p>
 109             <code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>level</code></em> is less than 0.
 110         </p><p>
 111             <code class="constant">GL_INVALID_VALUE</code> may be generated if
 112             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 113
 114                 <mml:mrow>
 115                     <mml:mi mathvariant="italic">level</mml:mi>
 116                     <mml:mo>&gt;</mml:mo>
 117                     <mml:mrow>
 118                         <mml:msub><mml:mi mathvariant="italic">log</mml:mi>
 119                         <mml:mn>2</mml:mn>
 120                         </mml:msub>
 121                         <mml:mo>⁡</mml:mo>
 122                         <mml:mfenced open="(" close=")">
 123                             <mml:mi mathvariant="italic">max</mml:mi>
 124                         </mml:mfenced>
 125                     </mml:mrow>
 126                 </mml:mrow>
 127             </mml:math>,
 128             where
 129             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">max</mml:mi></mml:math>
 130             is the returned value of <code class="constant">GL_MAX_TEXTURE_SIZE</code>.
 131         </p><p>
 132             <code class="constant">GL_INVALID_VALUE</code> is generated if
 133             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 134
 135                 <mml:mrow>
 136                     <mml:mi mathvariant="italic">xoffset</mml:mi>
 137                     <mml:mo>&lt;</mml:mo>
 138                     <mml:mn>0</mml:mn>
 139                 </mml:mrow>
 140             </mml:math>,
 141             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 142
 143                 <mml:mrow>
 144                     <mml:mfenced open="(" close=")">
 145                         <mml:mrow>
 146                             <mml:mi mathvariant="italic">xoffset</mml:mi>
 147                             <mml:mo>+</mml:mo>
 148                             <mml:mi mathvariant="italic">width</mml:mi>
 149                         </mml:mrow>
 150                     </mml:mfenced>
 151                     <mml:mo>&gt;</mml:mo>
 152                     <mml:mrow>
 153                         <mml:mi mathvariant="italic">w</mml:mi>
 154                     </mml:mrow>
 155                 </mml:mrow>
 156             </mml:math>,
 157             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 158
 159                 <mml:mrow>
 160                     <mml:mi mathvariant="italic">yoffset</mml:mi>
 161                     <mml:mo>&lt;</mml:mo>
 162                     <mml:mn>0</mml:mn>
 163                 </mml:mrow>
 164             </mml:math>,
 165             or
 166             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 167
 168                 <mml:mrow>
 169                     <mml:mfenced open="(" close=")">
 170                         <mml:mrow>
 171                             <mml:mi mathvariant="italic">yoffset</mml:mi>
 172                             <mml:mo>+</mml:mo>
 173                             <mml:mi mathvariant="italic">height</mml:mi>
 174                         </mml:mrow>
 175                     </mml:mfenced>
 176                     <mml:mo>&gt;</mml:mo>
 177                     <mml:mi mathvariant="italic">h</mml:mi>
 178                 </mml:mrow>
 179             </mml:math>,
 180             where
 181             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">w</mml:mi></mml:math>
 182             is the <code class="constant">GL_TEXTURE_WIDTH</code>, and
 183             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">h</mml:mi></mml:math>
 184             is the <code class="constant">GL_TEXTURE_HEIGHT</code>
 185             of the texture image being modified.
 186         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
 187             <a href="glGetTexImage.xml"><span class="citerefentry"><span class="refentrytitle">glGetTexImage</span></span></a>
 188         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
 189             <a href="glCopyTexImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage1D</span></span></a>,
 190             <a href="glCopyTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage2D</span></span></a>,
 191             <a href="glCopyTexSubImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage1D</span></span></a>,
 192             <a href="glCopyTexSubImage3D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage3D</span></span></a>,
 193             <a href="glPixelStore.xml"><span class="citerefentry"><span class="refentrytitle">glPixelStore</span></span></a>,
 194             <a href="glReadBuffer.xml"><span class="citerefentry"><span class="refentrytitle">glReadBuffer</span></span></a>,
 195             <a href="glTexImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage1D</span></span></a>,
 196             <a href="glTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage2D</span></span></a>,
 197             <a href="glTexImage3D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage3D</span></span></a>,
 198             <a href="glTexParameter.xml"><span class="citerefentry"><span class="refentrytitle">glTexParameter</span></span></a>,
 199             <a href="glTexSubImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage1D</span></span></a>,
 200             <a href="glTexSubImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage2D</span></span></a>,
 201             <a href="glTexSubImage3D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage3D</span></span></a>
 202         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
 203             Copyright <span class="trademark"></span>© 1991-2006
 204             Silicon Graphics, Inc. This document is licensed under the SGI
 205             Free Software B License. For details, see
 206             <a href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
 207         </p></div></div></body></html>