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glCopyTexImage2D.xhtml
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<div class="refentry"><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 class="funcprototype-table" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">void <strong class="fsfunc">glCopyTexImage2D</strong>(</code></td><td>GLenum <var class="pdparam">target</var>, </td></tr><tr><td> </td><td>GLint <var class="pdparam">level</var>, </td></tr><tr><td> </td><td>GLenum <var class="pdparam">internalformat</var>, </td></tr><tr><td> </td><td>GLint <var class="pdparam">x</var>, </td></tr><tr><td> </td><td>GLint <var class="pdparam">y</var>, </td></tr><tr><td> </td><td>GLsizei <var class="pdparam">width</var>, </td></tr><tr><td> </td><td>GLsizei <var class="pdparam">height</var>, </td></tr><tr><td> </td><td>GLint <var class="pdparam">border</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>target</code></em></span></dt><dd><p>
Specifies the target texture.
Must be <code class="constant">GL_TEXTURE_2D</code>,
<code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_X</code>,
<code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_X</code>,
<code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_Y</code>,
<code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_Y</code>,
<code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_Z</code>, or
<code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_Z</code>.
</p></dd><dt><span class="term"><em class="parameter"><code>level</code></em></span></dt><dd><p>
Specifies the level-of-detail number.
Level 0 is the base image level.
Level <span class="emphasis"><em>n</em></span> is the <span class="emphasis"><em>n</em></span>th mipmap reduction image.
</p></dd><dt><span class="term"><em class="parameter"><code>internalformat</code></em></span></dt><dd><p>
Specifies the internal format of the texture.
Must be one of the following symbolic constants:
<code class="constant">GL_COMPRESSED_RED</code>,
<code class="constant">GL_COMPRESSED_RG</code>,
<code class="constant">GL_COMPRESSED_RGB</code>,
<code class="constant">GL_COMPRESSED_RGBA</code>.
<code class="constant">GL_COMPRESSED_SRGB</code>,
<code class="constant">GL_COMPRESSED_SRGB_ALPHA</code>.
<code class="constant">GL_DEPTH_COMPONENT</code>,
<code class="constant">GL_DEPTH_COMPONENT16</code>,
<code class="constant">GL_DEPTH_COMPONENT24</code>,
<code class="constant">GL_DEPTH_COMPONENT32</code>,
<code class="constant">GL_RED</code>,
<code class="constant">GL_RG</code>,
<code class="constant">GL_RGB</code>,
<code class="constant">GL_R3_G3_B2</code>,
<code class="constant">GL_RGB4</code>,
<code class="constant">GL_RGB5</code>,
<code class="constant">GL_RGB8</code>,
<code class="constant">GL_RGB10</code>,
<code class="constant">GL_RGB12</code>,
<code class="constant">GL_RGB16</code>,
<code class="constant">GL_RGBA</code>,
<code class="constant">GL_RGBA2</code>,
<code class="constant">GL_RGBA4</code>,
<code class="constant">GL_RGB5_A1</code>,
<code class="constant">GL_RGBA8</code>,
<code class="constant">GL_RGB10_A2</code>,
<code class="constant">GL_RGBA12</code>,
<code class="constant">GL_RGBA16</code>,
<code class="constant">GL_SRGB</code>,
<code class="constant">GL_SRGB8</code>,
<code class="constant">GL_SRGB_ALPHA</code>, or
<code class="constant">GL_SRGB8_ALPHA8</code>.
</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>
Specify the window coordinates of the lower left corner
of the rectangular region of pixels to be copied.
</p></dd><dt><span class="term"><em class="parameter"><code>width</code></em></span></dt><dd><p>
Specifies the width of the texture image.
</p></dd><dt><span class="term"><em class="parameter"><code>height</code></em></span></dt><dd><p>
Specifies the height of the texture image.
</p></dd><dt><span class="term"><em class="parameter"><code>border</code></em></span></dt><dd><p>
Must be 0.
</p></dd></dl></div></div><div class="refsect1"><a id="description"></a><h2>Description</h2><p>
<code class="function">glCopyTexImage2D</code> defines a two-dimensional texture image, or cube-map texture image
with pixels from the current
<code class="constant">GL_READ_BUFFER</code>.
</p><p>
The screen-aligned pixel rectangle with lower left corner at (<em class="parameter"><code>x</code></em>,
<em class="parameter"><code>y</code></em>) and with a width of
<math overflow="scroll">
<mrow>
<mi mathvariant="italic">width</mi>
</mrow>
</math>
and a height of
<math overflow="scroll">
<mrow>
<mi mathvariant="italic">height</mi>
</mrow>
</math>
defines the texture array
at the mipmap level specified by <em class="parameter"><code>level</code></em>.
<em class="parameter"><code>internalformat</code></em> specifies the internal format of the texture array.
</p><p>
The pixels in the rectangle are processed exactly as if
<a class="citerefentry" href="glReadPixels"><span class="citerefentry"><span class="refentrytitle">glReadPixels</span></span></a> had been called, but the process stops just before
final conversion.
At this point all pixel component values are clamped to the range
<math overflow="scroll">
<mfenced open="[" close="]">
<mn>0</mn>
<mn>1</mn>
</mfenced>
</math>
and then converted to the texture's internal format for storage in the texel
array.
</p><p>
Pixel ordering is such that lower
<math overflow="scroll"><mi mathvariant="italic">x</mi></math>
and
<math overflow="scroll"><mi mathvariant="italic">y</mi></math>
screen coordinates correspond to
lower
<math overflow="scroll"><mi mathvariant="italic">s</mi></math>
and
<math overflow="scroll"><mi mathvariant="italic">t</mi></math>
texture coordinates.
</p><p>
If any of the pixels within the specified rectangle of the current
<code class="constant">GL_READ_BUFFER</code> are outside the window associated with the current
rendering context, then the values obtained for those pixels are undefined.
</p><p>
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.
</p></div><div class="refsect1"><a id="notes"></a><h2>Notes</h2><p>
1, 2, 3, and 4 are not accepted values for <em class="parameter"><code>internalformat</code></em>.
</p><p>
An image with height or width of 0 indicates a NULL texture.
</p></div><div class="refsect1"><a id="errors"></a><h2>Errors</h2><p>
<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>,
<code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_X</code>,
<code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_X</code>,
<code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_Y</code>,
<code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_Y</code>,
<code class="constant">GL_TEXTURE_CUBE_MAP_POSITIVE_Z</code>, or
<code class="constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_Z</code>.
</p><p>
<code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>level</code></em> is less than 0.
</p><p>
<code class="constant">GL_INVALID_VALUE</code> may be generated if <em class="parameter"><code>level</code></em> is greater
than
<math overflow="scroll">
<mrow>
<msub><mi mathvariant="italic">log</mi>
<mn>2</mn>
</msub>
<mo></mo>
<mi mathvariant="italic">max</mi>
</mrow>
</math>,
where
<math overflow="scroll"><mi mathvariant="italic">max</mi></math>
is the returned value of <code class="constant">GL_MAX_TEXTURE_SIZE</code>.
</p><p>
<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
or greater than
<code class="constant">GL_MAX_TEXTURE_SIZE</code>.
</p><p>
<code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>border</code></em> is not 0.
</p><p>
<code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>internalformat</code></em> is not an
accepted format.
</p><p>
<code class="constant">GL_INVALID_OPERATION</code> is generated if <em class="parameter"><code>internalformat</code></em> is
<code class="constant">GL_DEPTH_COMPONENT</code>, <code class="constant">GL_DEPTH_COMPONENT16</code>,
<code class="constant">GL_DEPTH_COMPONENT24</code>, or <code class="constant">GL_DEPTH_COMPONENT32</code> and there is no depth
buffer.
</p></div><div class="refsect1"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
<a class="citerefentry" href="glGetTexImage"><span class="citerefentry"><span class="refentrytitle">glGetTexImage</span></span></a>
</p></div>
{$pipelinestall}{$examples}
<div class="refsect1"><a id="seealso"></a><h2>See Also</h2><p>
<a class="citerefentry" href="glCopyTexImage1D"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage1D</span></span></a>,
<a class="citerefentry" href="glCopyTexSubImage1D"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage1D</span></span></a>,
<a class="citerefentry" href="glCopyTexSubImage2D"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage2D</span></span></a>,
<a class="citerefentry" href="glPixelStore"><span class="citerefentry"><span class="refentrytitle">glPixelStore</span></span></a>,
<a class="citerefentry" href="glTexImage1D"><span class="citerefentry"><span class="refentrytitle">glTexImage1D</span></span></a>,
<a class="citerefentry" href="glTexImage2D"><span class="citerefentry"><span class="refentrytitle">glTexImage2D</span></span></a>,
<a class="citerefentry" href="glTexSubImage1D"><span class="citerefentry"><span class="refentrytitle">glTexSubImage1D</span></span></a>,
<a class="citerefentry" href="glTexSubImage2D"><span class="citerefentry"><span class="refentrytitle">glTexSubImage2D</span></span></a>,
<a class="citerefentry" href="glTexParameter"><span class="citerefentry"><span class="refentrytitle">glTexParameter</span></span></a>
</p></div><div class="refsect1"><div id="Copyright"><h2>Copyright</h2><p>
Copyright © 1991-2006
Silicon Graphics, Inc. This document is licensed under the SGI
Free Software B License. For details, see
<a class="ulink" href="https://web.archive.org/web/20171022161616/http://oss.sgi.com/projects/FreeB/" target="_top">https://web.archive.org/web/20171022161616/http://oss.sgi.com/projects/FreeB/</a>.
</p></div></div></div>