upstream-doc/man4/xhtml/glCompressedTexImage1D.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "xhtml1-transitional.dtd">
   3 <!-- saved from url=(0013)about:internet -->
   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>glCompressedTexImage1D - OpenGL 4 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="glCompressedTexImage1D"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glCompressedTexImage1D — specify a one-dimensional texture image in a compressed format</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">glCompressedTexImage1D</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>GLsizei  </td><td><var class="pdparam">width</var>, </td></tr><tr><td> </td><td>GLint  </td><td><var class="pdparam">border</var>, </td></tr><tr><td> </td><td>GLsizei  </td><td><var class="pdparam">imageSize</var>, </td></tr><tr><td> </td><td>const GLvoid *  </td><td><var class="pdparam">data</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_1D</code> or <code class="constant">GL_PROXY_TEXTURE_1D</code>.
   7                 </p></dd><dt><span class="term"><em class="parameter"><code>level</code></em></span></dt><dd><p>
   8                     Specifies the level-of-detail number.
   9                     Level 0 is the base image level.
  10                     Level <span class="emphasis"><em>n</em></span> is the <span class="emphasis"><em>n</em></span>th mipmap reduction image.
  11                 </p></dd><dt><span class="term"><em class="parameter"><code>internalformat</code></em></span></dt><dd><p>
  12                     Specifies the format of the compressed image data stored at address <em class="parameter"><code>data</code></em>.
  13                 </p></dd><dt><span class="term"><em class="parameter"><code>width</code></em></span></dt><dd><p>
  14                     Specifies the width of the texture image.
  15                     All implementations support texture images that are at least 64 texels wide. The height of the 1D texture image is 1.
  16                 </p></dd><dt><span class="term"><em class="parameter"><code>border</code></em></span></dt><dd><p>
  17                     This value must be 0.
  18                 </p></dd><dt><span class="term"><em class="parameter"><code>imageSize</code></em></span></dt><dd><p>
  19                     Specifies the number of unsigned bytes of image data starting at the address specified by <em class="parameter"><code>data</code></em>.
  20                 </p></dd><dt><span class="term"><em class="parameter"><code>data</code></em></span></dt><dd><p>
  21                     Specifies a pointer to the compressed image data in memory.
  22                 </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
  23             Texturing allows elements of an image array to be read by shaders.
  24         </p><p>
  25             <code class="function">glCompressedTexImage1D</code> loads a previously defined, and retrieved, compressed
  26             one-dimensional texture image if <em class="parameter"><code>target</code></em> is <code class="constant">GL_TEXTURE_1D</code>
  27             (see <a href="glTexImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage1D</span></span></a>).
  28         </p><p>
  29             If <em class="parameter"><code>target</code></em> is <code class="constant">GL_PROXY_TEXTURE_1D</code>, no data is read from <em class="parameter"><code>data</code></em>, but
  30             all of the texture image state is recalculated, checked for consistency, and checked against the implementation's capabilities.  If the implementation cannot handle a texture of the requested texture size, it sets all of the image state to 0, but does not generate an error (see <a href="glGetError.xml"><span class="citerefentry"><span class="refentrytitle">glGetError</span></span></a>). To query for an entire mipmap array, use an image array level greater than or equal to 1.
  31         </p><p>
  32             <em class="parameter"><code>internalformat</code></em> must be an extension-specified compressed-texture format.
  33             When a texture is loaded with
  34             <a href="glTexImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage1D</span></span></a> using a generic compressed  texture format
  35             (e.g., <code class="constant">GL_COMPRESSED_RGB</code>) the GL selects from one of
  36             its extensions supporting compressed textures.  In order to load the
  37             compressed texture image using <code class="function">glCompressedTexImage1D</code>, query the compressed texture image's size and
  38             format using <a href="glGetTexLevelParameter.xml"><span class="citerefentry"><span class="refentrytitle">glGetTexLevelParameter</span></span></a>.
  39         </p><p>
  40             If a non-zero named buffer object is bound to the <code class="constant">GL_PIXEL_UNPACK_BUFFER</code> target
  41             (see <a href="glBindBuffer.xml"><span class="citerefentry"><span class="refentrytitle">glBindBuffer</span></span></a>) while a texture image is
  42             specified, <em class="parameter"><code>data</code></em> is treated as a byte offset into the buffer object's data store.
  43         </p><p>
  44             If the compressed data are arranged into fixed-size blocks of texels, the pixel
  45             storage modes can be used to select a sub-rectangle from a larger containing rectangle.
  46             These pixel storage modes operate in the same way as they do for <a href="glTexImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage1D</span></span></a>.
  47             In the following description, denote by <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mrow><mml:msub><mml:mi>b</mml:mi><mml:mi>s</mml:mi></mml:msub></mml:mrow></mml:math>,
  48             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mrow><mml:msub><mml:mi>b</mml:mi><mml:mi>w</mml:mi></mml:msub></mml:mrow></mml:math>,
  49             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mrow><mml:msub><mml:mi>b</mml:mi><mml:mi>h</mml:mi></mml:msub></mml:mrow></mml:math>, and
  50             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mrow><mml:msub><mml:mi>b</mml:mi><mml:mi>d</mml:mi></mml:msub></mml:mrow></mml:math>,
  51             the values of pixel storage modes <code class="constant">GL_UNPACK_COMPRESSED_BLOCK_SIZE</code>,
  52             <code class="constant">GL_UNPACK_COMPRESSED_BLOCK_WIDTH</code>, <code class="constant">GL_UNPACK_COMPRESSED_BLOCK_HEIGHT</code>,
  53             and <code class="constant">GL_UNPACK_COMPRESSED_BLOCK_DEPTH</code>, respectively.
  54             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mrow><mml:msub><mml:mi>b</mml:mi><mml:mi>s</mml:mi></mml:msub></mml:mrow></mml:math> is
  55             the compressed block size in bytes; <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mrow><mml:msub><mml:mi>b</mml:mi><mml:mi>w</mml:mi></mml:msub></mml:mrow></mml:math>,
  56             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mrow><mml:msub><mml:mi>b</mml:mi><mml:mi>h</mml:mi></mml:msub></mml:mrow></mml:math>,
  57             and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mrow><mml:msub><mml:mi>b</mml:mi><mml:mi>d</mml:mi></mml:msub></mml:mrow></mml:math> are the compressed block width, height, and depth in pixels.
  58         </p><p>
  59             By default the pixel storage modes <code class="constant">GL_UNPACK_ROW_LENGTH</code>,
  60             <code class="constant">GL_UNPACK_SKIP_ROWS</code>, <code class="constant">GL_UNPACK_SKIP_PIXELS</code>,
  61             <code class="constant">GL_UNPACK_IMAGE_HEIGHT</code> and <code class="constant">GL_UNPACK_SKIP_IMAGES</code>
  62             are ignored for compressed images. To enable <code class="constant">GL_UNPACK_SKIP_PIXELS</code>
  63             and <code class="constant">GL_UNPACK_ROW_LENGTH</code>, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mrow><mml:msub><mml:mi>b</mml:mi><mml:mi>s</mml:mi></mml:msub></mml:mrow></mml:math>
  64             and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mrow><mml:msub><mml:mi>b</mml:mi><mml:mi>w</mml:mi></mml:msub></mml:mrow></mml:math> must both be non-zero.
  65             To also enable <code class="constant">GL_UNPACK_SKIP_ROWS</code> and <code class="constant">GL_UNPACK_IMAGE_HEIGHT</code>,
  66             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mrow><mml:msub><mml:mi>b</mml:mi><mml:mi>h</mml:mi></mml:msub></mml:mrow></mml:math> must be non-zero.
  67             To also enable <code class="constant">GL_UNPACK_SKIP_IMAGES</code>, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mrow><mml:msub><mml:mi>b</mml:mi><mml:mi>d</mml:mi></mml:msub></mml:mrow></mml:math>
  68             must be non-zero. All parameters must be consistent with the compressed format to produce the desired results.
  69         </p><p>
  70             When selecting a sub-rectangle from a compressed image:
  71             </p><div class="itemizedlist"><ul type="disc"><li>the value of <code class="constant">GL_UNPACK_SKIP_PIXELS</code> must be a multiple of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mrow><mml:msub><mml:mi>b</mml:mi><mml:mi>w</mml:mi></mml:msub></mml:mrow></mml:math>;</li></ul></div><p>
  72         </p><p>
  73             <em class="parameter"><code>imageSize</code></em> must be equal to:
  74         </p><p>
  75 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="block" overflow="scroll">
  76   <mml:mrow>
  77     <mml:msub>
  78       <mml:mi>b</mml:mi>
  79       <mml:mi>s</mml:mi>
  80     </mml:msub>
  81     <mml:mo lspace="2px" rspace="2px">×</mml:mo>
  82     <mml:mfenced open="&#x2308;" close="&#x2309;">
  83       <mml:mfrac>
  84         <mml:mi>width</mml:mi>
  85         <mml:msub>
  86           <mml:mi>b</mml:mi>
  87           <mml:mi>w</mml:mi>
  88         </mml:msub>
  89       </mml:mfrac>
  90     </mml:mfenced>
  91   </mml:mrow>
  92 </mml:math>
  93         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
  94           <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>internalformat</code></em> is not
  95           a supported specific compressed internal formats, or is one of the generic
  96           compressed internal formats:
  97           <code class="constant">GL_COMPRESSED_RED</code>,
  98           <code class="constant">GL_COMPRESSED_RG</code>,
  99           <code class="constant">GL_COMPRESSED_RGB</code>,
 100           <code class="constant">GL_COMPRESSED_RGBA</code>.
 101           <code class="constant">GL_COMPRESSED_SRGB</code>, or
 102           <code class="constant">GL_COMPRESSED_SRGB_ALPHA</code>.
 103         </p><p>
 104             <code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>imageSize</code></em> is not consistent with
 105             the format, dimensions, and contents of the specified compressed image data.
 106         </p><p>
 107             <code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>border</code></em> is not 0.
 108         </p><p>
 109             <code class="constant">GL_INVALID_OPERATION</code> is generated if parameter combinations are not
 110             supported by the specific compressed internal format as specified in the
 111             specific texture compression extension.
 112         </p><p>
 113             <code class="constant">GL_INVALID_OPERATION</code> is generated if a non-zero buffer object name is bound to the
 114             <code class="constant">GL_PIXEL_UNPACK_BUFFER</code> target and the buffer object's data store is currently mapped.
 115         </p><p>
 116             <code class="constant">GL_INVALID_OPERATION</code> is generated if a non-zero buffer object name is bound to the
 117             <code class="constant">GL_PIXEL_UNPACK_BUFFER</code> target and the data would be unpacked from the buffer
 118             object such that the memory reads required would exceed the data store size.
 119         </p><p>
 120             Undefined results, including abnormal program termination, are generated if
 121             <em class="parameter"><code>data</code></em> is not encoded in a manner consistent with the extension
 122             specification defining the internal compression format.
 123         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
 124             <a href="glGetCompressedTexImage.xml"><span class="citerefentry"><span class="refentrytitle">glGetCompressedTexImage</span></span></a>
 125         </p><p>
 126             <a href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_TEXTURE_COMPRESSED</code>
 127         </p><p>
 128             <a href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_NUM_COMPRESSED_TEXTURE_FORMATS</code>
 129         </p><p>
 130             <a href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_COMPRESSED_TEXTURE_FORMATS</code>
 131         </p><p>
 132             <a href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_PIXEL_UNPACK_BUFFER_BINDING</code>
 133         </p><p>
 134             <a href="glGetTexLevelParameter.xml"><span class="citerefentry"><span class="refentrytitle">glGetTexLevelParameter</span></span></a> with arguments <code class="constant">GL_TEXTURE_INTERNAL_FORMAT</code>
 135             and <code class="constant">GL_TEXTURE_COMPRESSED_IMAGE_SIZE</code>
 136         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
 137             <a href="glActiveTexture.xml"><span class="citerefentry"><span class="refentrytitle">glActiveTexture</span></span></a>,
 138             <a href="glCompressedTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCompressedTexImage2D</span></span></a>,
 139             <a href="glCompressedTexImage3D.xml"><span class="citerefentry"><span class="refentrytitle">glCompressedTexImage3D</span></span></a>,
 140             <a href="glCompressedTexSubImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glCompressedTexSubImage1D</span></span></a>,
 141             <a href="glCompressedTexSubImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCompressedTexSubImage2D</span></span></a>,
 142             <a href="glCompressedTexSubImage3D.xml"><span class="citerefentry"><span class="refentrytitle">glCompressedTexSubImage3D</span></span></a>,
 143             <a href="glCopyTexImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage1D</span></span></a>,
 144             <a href="glCopyTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage2D</span></span></a>,
 145             <a href="glCopyTexSubImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage1D</span></span></a>,
 146             <a href="glCopyTexSubImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage2D</span></span></a>,
 147             <a href="glCopyTexSubImage3D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage3D</span></span></a>,
 148             <a href="glPixelStore.xml"><span class="citerefentry"><span class="refentrytitle">glPixelStore</span></span></a>,
 149             <a href="glTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage2D</span></span></a>,
 150             <a href="glTexImage3D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage3D</span></span></a>,
 151             <a href="glTexSubImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage1D</span></span></a>,
 152             <a href="glTexSubImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage2D</span></span></a>,
 153             <a href="glTexSubImage3D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage3D</span></span></a>,
 154             <a href="glTexParameter.xml"><span class="citerefentry"><span class="refentrytitle">glTexParameter</span></span></a>
 155         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
 156             Copyright <span class="trademark"></span>© 1991-2006
 157             Silicon Graphics, Inc. <span class="trademark"></span>© 2011
 158             Khronos Group. This document is licensed under the SGI
 159             Free Software B License. For details, see
 160             <a href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
 161         </p></div></div></body></html>