<div class="refentry"><a id="glCopyTexSubImage1D"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glCopyTexSubImage1D — copy a one-dimensional texture subimage</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">glCopyTexSubImage1D</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>GLint <var class="pdparam">xoffset</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><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><p>

</p><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_1D</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>xoffset</code></em></span></dt><dd><p>

Specifies the texel offset within the texture array.

</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 left corner

of the row 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 subimage.

</p></dd></dl></div></div><div class="refsect1"><a id="description"></a><h2>Description</h2><p>

<code class="function">glCopyTexSubImage1D</code> replaces a portion of a one-dimensional

texture image with pixels from the current <code class="constant">GL_READ_BUFFER</code> (rather

than from main memory, as is the case for <a class="citerefentry" href="glTexSubImage1D"><span class="citerefentry"><span class="refentrytitle">glTexSubImage1D</span></span></a>).

</p><p>

The screen-aligned pixel row with left corner at (<em class="parameter"><code>x</code></em>, <em class="parameter"><code>y</code></em>), and with

length <em class="parameter"><code>width</code></em> replaces the portion of the

texture array with x indices <em class="parameter"><code>xoffset</code></em> through

<math overflow="scroll">

<mrow>

<mi mathvariant="italic">xoffset</mi>

<mo>+</mo>

<mi mathvariant="italic">width</mi>

<mo>-</mo>

<mn>1</mn>

</mrow>

</math>,

inclusive. The destination in the texture array may not

include any texels outside the texture array as it was

originally specified.

</p><p>

The pixels in the row 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>

It is not an error to specify a subtexture with zero width, but

such a specification has no effect.

If any of the pixels within the specified row of the current

<code class="constant">GL_READ_BUFFER</code> are outside the read window associated with the current

rendering context, then the values obtained for those pixels are undefined.

</p><p>

No change is made to the <span class="emphasis"><em>internalformat</em></span> or <span class="emphasis"><em>width</em></span> parameters of the specified texture

array or to texel values outside the specified subregion.

</p></div><div class="refsect1"><a id="notes"></a><h2>Notes</h2><p>

The <a class="citerefentry" href="glPixelStore"><span class="citerefentry"><span class="refentrytitle">glPixelStore</span></span></a> mode affects texture images.

</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_1D</code>.

</p><p>

<code class="constant">GL_INVALID_OPERATION</code> is generated if the texture array has not

been defined by a previous <a class="citerefentry" href="glTexImage1D"><span class="citerefentry"><span class="refentrytitle">glTexImage1D</span></span></a> or <a class="citerefentry" href="glCopyTexImage1D"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage1D</span></span></a> operation.

</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

<math overflow="scroll">

<mrow>

<mi mathvariant="italic">level</mi>

<mo>&gt;</mo>

<mrow>

<msub><mi mathvariant="italic">log</mi>

<mn>2</mn>

</msub>

<mo>⁡</mo>

<mfenced open="(" close=")">

<mi mathvariant="italic">max</mi>

</mfenced>

</mrow>

</mrow>

</math>,

where <span class="emphasis"><em>max</em></span> 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

<math overflow="scroll">

<mrow>

<mi mathvariant="italic">xoffset</mi>

<mo>&lt;</mo>

<mn>0</mn>

</mrow>

</math>,

or

<math overflow="scroll">

<mrow>

<mfenced open="(" close=")">

<mrow>

<mi mathvariant="italic">xoffset</mi>

<mo>+</mo>

<mi mathvariant="italic">width</mi>

</mrow>

</mfenced>

<mo>&gt;</mo>

<mi mathvariant="italic">w</mi>

</mrow>

</math>,

where

<math overflow="scroll"><mi mathvariant="italic">w</mi></math>

is the <code class="constant">GL_TEXTURE_WIDTH</code>

of the texture image being modified.

</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="glCopyTexImage2D"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage2D</span></span></a>,

<a class="citerefentry" href="glCopyTexSubImage2D"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage2D</span></span></a>,

<a class="citerefentry" href="glCopyTexSubImage3D"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage3D</span></span></a>,

<a class="citerefentry" href="glPixelStore"><span class="citerefentry"><span class="refentrytitle">glPixelStore</span></span></a>,

<a class="citerefentry" href="glReadBuffer"><span class="citerefentry"><span class="refentrytitle">glReadBuffer</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="glTexImage3D"><span class="citerefentry"><span class="refentrytitle">glTexImage3D</span></span></a>,

<a class="citerefentry" href="glTexParameter"><span class="citerefentry"><span class="refentrytitle">glTexParameter</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="glTexSubImage3D"><span class="citerefentry"><span class="refentrytitle">glTexSubImage3D</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>