upstream-doc/man3/xhtml/glCopyTexImage2D.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>glCopyTexImage2D - 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="glCopyTexImage2D"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glCopyTexImage2D — copy pixels into a 2D texture image</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">glCopyTexImage2D</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>GLenum  </td><td><var class="pdparam">internalformat</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>, </td></tr><tr><td> </td><td>GLint  </td><td><var class="pdparam">border</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>target</code></em></span></dt><dd><p>
   5                     Specifies the target texture.
   6                     Must be <code class="constant">GL_TEXTURE_2D</code>,
   7                     <code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_X</code>,
   8                     <code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_X</code>,
   9                     <code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_Y</code>,
  10                     <code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_Y</code>,
  11                     <code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_Z</code>, or
  12                     <code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_Z</code>.
  13                 </p></dd><dt><span class="term"><em class="parameter"><code>level</code></em></span></dt><dd><p>
  14                     Specifies the level-of-detail number.
  15                     Level 0 is the base image level.
  16                     Level <span class="emphasis"><em>n</em></span> is the <span class="emphasis"><em>n</em></span>th mipmap reduction image.
  17                 </p></dd><dt><span class="term"><em class="parameter"><code>internalformat</code></em></span></dt><dd><p>
  18                     Specifies the internal format of the texture.
  19                     Must be one of the following symbolic constants:
  20                     <code class="constant">GL_COMPRESSED_RED</code>,
  21                     <code class="constant">GL_COMPRESSED_RG</code>,
  22                     <code class="constant">GL_COMPRESSED_RGB</code>,
  23                     <code class="constant">GL_COMPRESSED_RGBA</code>.
  24                     <code class="constant">GL_COMPRESSED_SRGB</code>,
  25                     <code class="constant">GL_COMPRESSED_SRGB_ALPHA</code>.
  26                     <code class="constant">GL_DEPTH_COMPONENT</code>,
  27                     <code class="constant">GL_DEPTH_COMPONENT16</code>,
  28                     <code class="constant">GL_DEPTH_COMPONENT24</code>,
  29                     <code class="constant">GL_DEPTH_COMPONENT32</code>,
  30                     <code class="constant">GL_RED</code>,
  31                     <code class="constant">GL_RG</code>,
  32                     <code class="constant">GL_RGB</code>,
  33                     <code class="constant">GL_R3_G3_B2</code>,
  34                     <code class="constant">GL_RGB4</code>,
  35                     <code class="constant">GL_RGB5</code>,
  36                     <code class="constant">GL_RGB8</code>,
  37                     <code class="constant">GL_RGB10</code>,
  38                     <code class="constant">GL_RGB12</code>,
  39                     <code class="constant">GL_RGB16</code>,
  40                     <code class="constant">GL_RGBA</code>,
  41                     <code class="constant">GL_RGBA2</code>,
  42                     <code class="constant">GL_RGBA4</code>,
  43                     <code class="constant">GL_RGB5_A1</code>,
  44                     <code class="constant">GL_RGBA8</code>,
  45                     <code class="constant">GL_RGB10_A2</code>,
  46                     <code class="constant">GL_RGBA12</code>,
  47                     <code class="constant">GL_RGBA16</code>,
  48                     <code class="constant">GL_SRGB</code>,
  49                     <code class="constant">GL_SRGB8</code>,
  50                     <code class="constant">GL_SRGB_ALPHA</code>, or
  51                     <code class="constant">GL_SRGB8_ALPHA8</code>.
  52                 </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>
  53                     Specify the window coordinates of the lower left corner
  54                     of the rectangular region of pixels to be copied.
  55                 </p></dd><dt><span class="term"><em class="parameter"><code>width</code></em></span></dt><dd><p>
  56                     Specifies the width of the texture image.
  57                 </p></dd><dt><span class="term"><em class="parameter"><code>height</code></em></span></dt><dd><p>
  58                     Specifies the height of the texture image.
  59                 </p></dd><dt><span class="term"><em class="parameter"><code>border</code></em></span></dt><dd><p>
  60                     Must be 0.
  61                 </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
  62             <code class="function">glCopyTexImage2D</code> defines a two-dimensional texture image, or cube-map texture image
  63             with pixels from the current
  64             <code class="constant">GL_READ_BUFFER</code>.
  65         </p><p>
  66             The screen-aligned pixel rectangle with lower left corner at (<em class="parameter"><code>x</code></em>,
  67             <em class="parameter"><code>y</code></em>) and with a width of
  68             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  69
  70                 <mml:mrow>
  71                     <mml:mi mathvariant="italic">width</mml:mi>
  72                 </mml:mrow>
  73             </mml:math>
  74             and a height of
  75             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  76
  77                 <mml:mrow>
  78                     <mml:mi mathvariant="italic">height</mml:mi>
  79                 </mml:mrow>
  80             </mml:math>
  81             defines the texture array
  82             at the mipmap level specified by <em class="parameter"><code>level</code></em>.
  83             <em class="parameter"><code>internalformat</code></em> specifies the internal format of the texture array.
  84         </p><p>
  85             The pixels in the rectangle are processed exactly as if
  86             <a href="glReadPixels.xml"><span class="citerefentry"><span class="refentrytitle">glReadPixels</span></span></a> had been called, but the process stops just before
  87             final conversion.
  88             At this point all pixel component values are clamped to the range
  89             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  90
  91                 <mml:mfenced open="[" close="]">
  92                     <mml:mn>0</mml:mn>
  93                     <mml:mn>1</mml:mn>
  94                 </mml:mfenced>
  95             </mml:math>
  96             and then converted to the texture's internal format for storage in the texel
  97             array.
  98         </p><p>
  99             Pixel ordering is such that lower
 100             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">x</mml:mi></mml:math>
 101             and
 102             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">y</mml:mi></mml:math>
 103             screen coordinates correspond to
 104             lower
 105             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">s</mml:mi></mml:math>
 106             and
 107             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">t</mml:mi></mml:math>
 108             texture coordinates.
 109         </p><p>
 110             If any of the pixels within the specified rectangle of the current
 111             <code class="constant">GL_READ_BUFFER</code> are outside the window associated with the current
 112             rendering context, then the values obtained for those pixels are undefined.
 113         </p><p>
 114             When <em class="parameter"><code>internalformat</code></em> is one of the sRGB  types, the GL does not automatically convert the source pixels to the sRGB color space.  In this case, the <code class="function">glPixelMap</code> function can be used to accomplish the conversion.
 115         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
 116             1, 2, 3, and 4 are not accepted values for <em class="parameter"><code>internalformat</code></em>.
 117         </p><p>
 118             An image with height or width of 0 indicates a NULL texture.
 119         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
 120             <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>,
 121             <code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_X</code>,
 122             <code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_X</code>,
 123             <code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_Y</code>,
 124             <code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_Y</code>,
 125             <code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_Z</code>, or
 126             <code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_Z</code>.
 127         </p><p>
 128             <code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>level</code></em> is less than 0.
 129         </p><p>
 130             <code class="constant">GL_INVALID_VALUE</code> may be generated if <em class="parameter"><code>level</code></em> is greater
 131             than
 132             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 133
 134                 <mml:mrow>
 135                     <mml:msub><mml:mi mathvariant="italic">log</mml:mi>
 136                     <mml:mn>2</mml:mn>
 137                     </mml:msub>
 138                     <mml:mo>⁢</mml:mo>
 139                     <mml:mi mathvariant="italic">max</mml:mi>
 140                 </mml:mrow>
 141             </mml:math>,
 142             where
 143             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">max</mml:mi></mml:math>
 144             is the returned value of <code class="constant">GL_MAX_TEXTURE_SIZE</code>.
 145         </p><p>
 146             <code class="constant">GL_INVALID_VALUE</code> is generated if either <em class="parameter"><code>width</code></em> or <em class="parameter"><code>height</code></em> is less than 0
 147             or greater than
 148             <code class="constant">GL_MAX_TEXTURE_SIZE</code>.
 149         </p><p>
 150             <code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>border</code></em> is not 0.
 151         </p><p>
 152             <code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>internalformat</code></em> is not an
 153             accepted format.
 154         </p><p>
 155             <code class="constant">GL_INVALID_OPERATION</code> is generated if <em class="parameter"><code>internalformat</code></em> is
 156             <code class="constant">GL_DEPTH_COMPONENT</code>, <code class="constant">GL_DEPTH_COMPONENT16</code>,
 157             <code class="constant">GL_DEPTH_COMPONENT24</code>, or <code class="constant">GL_DEPTH_COMPONENT32</code> and there is no depth
 158             buffer.
 159         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
 160             <a href="glGetTexImage.xml"><span class="citerefentry"><span class="refentrytitle">glGetTexImage</span></span></a>
 161         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
 162             <a href="glCopyTexImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage1D</span></span></a>,
 163             <a href="glCopyTexSubImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage1D</span></span></a>,
 164             <a href="glCopyTexSubImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage2D</span></span></a>,
 165             <a href="glPixelStore.xml"><span class="citerefentry"><span class="refentrytitle">glPixelStore</span></span></a>,
 166             <a href="glTexImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage1D</span></span></a>,
 167             <a href="glTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage2D</span></span></a>,
 168             <a href="glTexSubImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage1D</span></span></a>,
 169             <a href="glTexSubImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage2D</span></span></a>,
 170             <a href="glTexParameter.xml"><span class="citerefentry"><span class="refentrytitle">glTexParameter</span></span></a>
 171         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
 172             Copyright <span class="trademark"></span>© 1991-2006
 173             Silicon Graphics, Inc. This document is licensed under the SGI
 174             Free Software B License. For details, see
 175             <a href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
 176         </p></div></div></body></html>