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<refentry id="glCompressedTexImage1D">
<refmeta>
<refmetainfo>
<copyright>
<year>1991-2006</year>
<holder>Silicon Graphics, Inc.</holder>
</copyright>
</refmetainfo>
<refentrytitle>glCompressedTexImage1D</refentrytitle>
<manvolnum>3G</manvolnum>
</refmeta>
<refnamediv>
<refname>glCompressedTexImage1D</refname>
<refpurpose>specify a one-dimensional texture image in a compressed format</refpurpose>
</refnamediv>
<refsynopsisdiv><title>C Specification</title>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>glCompressedTexImage1D</function></funcdef>
<paramdef>GLenum <parameter>target</parameter></paramdef>
<paramdef>GLint <parameter>level</parameter></paramdef>
<paramdef>GLenum <parameter>internalformat</parameter></paramdef>
<paramdef>GLsizei <parameter>width</parameter></paramdef>
<paramdef>GLint <parameter>border</parameter></paramdef>
<paramdef>GLsizei <parameter>imageSize</parameter></paramdef>
<paramdef>const GLvoid * <parameter>data</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<!-- eqn: ignoring delim $$ -->
<refsect1 id="parameters"><title>Parameters</title>
<variablelist>
<varlistentry>
<term><parameter>target</parameter></term>
<listitem>
<para>
Specifies the target texture.
Must be <constant>GL_TEXTURE_1D</constant> or <constant>GL_PROXY_TEXTURE_1D</constant>.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>level</parameter></term>
<listitem>
<para>
Specifies the level-of-detail number.
Level 0 is the base image level.
Level <emphasis>n</emphasis> is the <emphasis>n</emphasis>th mipmap reduction image.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>internalformat</parameter></term>
<listitem>
<para>
Specifies the format of the compressed image data stored at address <parameter>data</parameter>.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>width</parameter></term>
<listitem>
<para>
Specifies the width of the texture image including the border if any. If the GL version does not support non-power-of-two sizes, this value must be
<inlineequation><mml:math>
<!-- eqn: 2 sup n + 2 ( border ):-->
<mml:mrow>
<mml:msup><mml:mn>2</mml:mn>
<mml:mi mathvariant="italic">n</mml:mi>
</mml:msup>
<mml:mo>+</mml:mo>
<mml:mrow>
<mml:mn>2</mml:mn>
<mml:mo>⁡</mml:mo>
<mml:mfenced open="(" close=")">
<mml:mi mathvariant="italic">border</mml:mi>
</mml:mfenced>
</mml:mrow>
</mml:mrow>
</mml:math></inlineequation>
for some integer
<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>.
All implementations support texture images that are at least 64 texels wide. The height of the 1D texture image is 1.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>border</parameter></term>
<listitem>
<para>
Specifies the width of the border. Must be either 0 or 1.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>imageSize</parameter></term>
<listitem>
<para>
Specifies the number of unsigned bytes of image data starting at the address specified by <parameter>data</parameter>.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>data</parameter></term>
<listitem>
<para>
Specifies a pointer to the compressed image data in memory.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 id="description"><title>Description</title>
<para>
Texturing maps a portion of a specified texture image onto each graphical primitive for which texturing is enabled. To enable and disable one-dimensional texturing, call <citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry> and <citerefentry><refentrytitle>glDisable</refentrytitle></citerefentry> with argument <constant>GL_TEXTURE_1D</constant>.
</para>
<para>
<function>glCompressedTexImage1D</function> loads a previously defined, and retrieved, compressed one-dimensional texture image if <parameter>target</parameter> is <constant>GL_TEXTURE_1D</constant> (see <citerefentry><refentrytitle>glTexImage1D</refentrytitle></citerefentry>).
</para>
<para>
If <parameter>target</parameter> is <constant>GL_PROXY_TEXTURE_1D</constant>, no data is read from <parameter>data</parameter>, but
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 <citerefentry><refentrytitle>glGetError</refentrytitle></citerefentry>). To query for an entire mipmap array, use an image array level greater than or equal to 1.
</para>
<para>
<parameter>internalformat</parameter> must be extension-specified compressed-texture format. When a texture is loaded with <citerefentry><refentrytitle>glTexImage1D</refentrytitle></citerefentry> using a generic compressed texture format (e.g., <constant>GL_COMPRESSED_RGB</constant>) the GL selects from one of
its extensions supporting compressed textures. In order to load the
compressed texture image using <function>glCompressedTexImage1D</function>, query the compressed texture image's size and format using <citerefentry><refentrytitle>glGetTexLevelParameter</refentrytitle></citerefentry>.
</para>
<para>
If a non-zero named buffer object is bound to the <constant>GL_PIXEL_UNPACK_BUFFER</constant> target
(see <citerefentry><refentrytitle>glBindBuffer</refentrytitle></citerefentry>) while a texture image is
specified, <parameter>data</parameter> is treated as a byte offset into the buffer object's data store.
</para>
</refsect1>
<refsect1 id="notes"><title>Notes</title>
<para>
<function>glCompressedTexImage1D</function> is available only if the GL version is 1.3 or greater.
</para>
<para>
Non-power-of-two textures are supported if the GL version is 2.0 or greater, or if the implementation exports the <constant>GL_ARB_texture_non_power_of_two</constant> extension.
</para>
</refsect1>
<refsect1 id="errors"><title>Errors</title>
<para>
<constant>GL_INVALID_ENUM</constant> is generated if <parameter>internalformat</parameter> is one of the generic compressed internal formats: <constant>GL_COMPRESSED_ALPHA</constant>,
<constant>GL_COMPRESSED_LUMINANCE</constant>, <constant>GL_COMPRESSED_LUMINANCE_ALPHA</constant>,
<constant>GL_COMPRESSED_INTENSITY</constant>, <constant>GL_COMPRESSED_RGB</constant>, or
<constant>GL_COMPRESSED_RGBA</constant>.
</para>
<para>
<constant>GL_INVALID_VALUE</constant> is generated if <parameter>imageSize</parameter> is not consistent with
the format, dimensions, and contents of the specified compressed image
data.
</para>
<para>
<constant>GL_INVALID_OPERATION</constant> is generated if parameter combinations are not
supported by the specific compressed internal format as specified in the
specific texture compression extension.
</para>
<para>
<constant>GL_INVALID_OPERATION</constant> is generated if a non-zero buffer object name is bound to the
<constant>GL_PIXEL_UNPACK_BUFFER</constant> target and the buffer object's data store is currently mapped.
</para>
<para>
<constant>GL_INVALID_OPERATION</constant> is generated if a non-zero buffer object name is bound to the
<constant>GL_PIXEL_UNPACK_BUFFER</constant> target and the data would be unpacked from the buffer
object such that the memory reads required would exceed the data store size.
</para>
<para>
<constant>GL_INVALID_OPERATION</constant> is generated if <function>glCompressedTexImage1D</function>
is executed between the execution of <citerefentry><refentrytitle>glBegin</refentrytitle></citerefentry>
and the corresponding execution of <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
</para>
<para>
Undefined results, including abnormal program termination, are generated if
<parameter>data</parameter> is not encoded in a manner consistent with the extension
specification defining the internal compression format.
</para>
</refsect1>
<refsect1 id="associatedgets"><title>Associated Gets</title>
<para>
<citerefentry><refentrytitle>glGetCompressedTexImage</refentrytitle></citerefentry>
</para>
<para>
<citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_TEXTURE_COMPRESSED</constant>
</para>
<para>
<citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_PIXEL_UNPACK_BUFFER_BINDING</constant>
</para>
<para>
<citerefentry><refentrytitle>glGetTexLevelParameter</refentrytitle></citerefentry> with arguments <constant>GL_TEXTURE_INTERNAL_FORMAT</constant>
and <constant>GL_TEXTURE_COMPRESSED_IMAGE_SIZE</constant>
</para>
<para>
<citerefentry><refentrytitle>glIsEnabled</refentrytitle></citerefentry> with argument <constant>GL_TEXTURE_1D</constant>
</para>
</refsect1>
<refsect1 id="seealso"><title>See Also</title>
<para>
<citerefentry><refentrytitle>glActiveTexture</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glColorTable</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glCompressedTexImage2D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glCompressedTexImage3D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glCompressedTexSubImage1D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glCompressedTexSubImage2D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glCompressedTexSubImage3D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glConvolutionFilter1D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glCopyPixels</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glCopyTexImage1D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glCopyTexImage2D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glCopyTexSubImage1D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glCopyTexSubImage2D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glCopyTexSubImage3D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glDrawPixels</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glMatrixMode</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glPixelStore</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glPixelTransfer</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glTexEnv</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glTexGen</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glTexImage3D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glTexSubImage1D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glTexSubImage2D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glTexSubImage3D</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glTexParameter</refentrytitle></citerefentry>
</para>
</refsect1>
<refsect1 id="Copyright"><title>Copyright</title>
<para>
Copyright <trademark class="copyright"></trademark> 1991-2006
Silicon Graphics, Inc. This document is licensed under the SGI
Free Software B License. For details, see
<ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>.
</para>
</refsect1>
</refentry>