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<!-- imageMipmapFunctionsInc -->
<bridgehead>Mipmap read image functions:</bridgehead>
<para>
For the forms that take an <type>image2d_t</type> object,
use the coordinate <varname>coord.xy</varname> to
do an element lookup in the mip-level specified by
<varname>lod</varname> in the 2D image object specified
by <varname>image</varname>.
</para>
<para>
For the forms that use gradients, use the gradients to compute
the lod and coordinate <emphasis>coord.xy</emphasis> to do an
element lookup in
the mip-level specified by the computed lod in
the 2D image object specified by <varname>image</varname>.
</para>
<para>
For the forms that take an <type>image2d_array_t</type> object,
use the coordinate <emphasis>coord.xy</emphasis> to
do an element lookup in the 2D image identified by
<emphasis>coord.z</emphasis> and mip-level specified by
<varname>lod</varname> in the 2D image object specified
by <varname>image</varname>.
</para>
<para>
For the forms that take an <type>image2d_array_t</type>
object and that use gradients,
use the gradients to compute the lod coordinate
and <emphasis>coord.xy</emphasis> to
do an element lookup in the 2D image identified by
<emphasis>coord.z</emphasis> and mip-level specified by
<varname>lod</varname> in the 2D image object specified
by <varname>image</varname>.
</para>
<para>
When a multisample image is accessed in a kernel,
the access takes one vector of
integers describing which pixel to fetch and an
integer corresponding to the sample numbers
describing which sample within the pixel to fetch.
sample identifies the sample position in the
multi-sample image.
</para>
<para>
NOTE: <constant>CL_SAMPLER_NORMALIZED_COORDS</constant>
must be <constant>CL_TRUE</constant> for built-in functions
described in the table above that read from a
mip-mapped image; otherwise the behavior is
undefined. The value specified in the
<varname>lod</varname> argument is clamped to the minimum of (actual
number of mip-levels - 1) in the image or value
specified for <constant>CL_SAMPLER_LOD_MAX_KHR</constant>.
</para>
<!-- 17-Dec-2013, rev. 19 -->