sdk/2.0/docs/man/read_imagef3d.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
              "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">[
<!ENTITY imageFunctionsInc SYSTEM "imageFunctionsInc.xml">
<!ENTITY imageMappingInc SYSTEM "imageMappingInc.xml">
<!ENTITY imageMipmapFunctions3DInc SYSTEM "imageMipmapFunctions3DInc.xml">
]>

<refentry>
    <refentryinfo>
        <keywordset>
            <keyword>read_imagef (3D)</keyword>
        </keywordset>
    </refentryinfo>

    <refmeta>
        <refentrytitle>read_imagef (3D)</refentrytitle>

        <refmiscinfo>
            <copyright>
                <year>2007-2013</year>
                <holder>The Khronos Group Inc.
 Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and/or associated documentation files (the
"Materials"), to deal in the Materials without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Materials, and to
permit persons to whom the Materials are furnished to do so, subject to
the condition that this copyright notice and permission notice shall be included
in all copies or substantial portions of the Materials.</holder>
            </copyright>
        </refmiscinfo>
        <manvolnum>3</manvolnum>
    </refmeta>

<!-- ================================ SYNOPSIS -->

    <refnamediv id="read_image2d">
        <refname>read_imagef (3D)</refname>

        <refpurpose>
            Do an element lookup in the 3D image object, returning floating-point values.
        </refpurpose>
    </refnamediv>

    <refsynopsisdiv xmlns:xlink="http://www.w3.org/1999/xlink"><title></title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>
                    <link xlink:href="vectorDataTypes.html">float4</link>
                    <function>
                        read_imagef
                    </function>
                </funcdef>
                <paramdef>
                    <link xlink:href="otherDataTypes.html">image3d_t</link>
                    <parameter>image</parameter>
                </paramdef>
                <paramdef>
                    <link xlink:href="sampler_t.html">sampler_t</link>
                    <parameter>sampler</parameter>
                </paramdef>
                <paramdef>
                    <link xlink:href="vectorDataTypes.html">int4</link>
                    <parameter>coord</parameter>
                </paramdef>
            </funcprototype>
        </funcsynopsis>

        <funcsynopsis>
            <funcprototype>
                <funcdef>
                    <link xlink:href="vectorDataTypes.html">float4</link>
                    <function>
                        read_imagef
                    </function>
                </funcdef>
                <paramdef>
                    <link xlink:href="otherDataTypes.html">image3d_t</link>
                    <parameter>image</parameter>
                </paramdef>
                <paramdef>
                    <link xlink:href="sampler_t.html">sampler_t</link>
                    <parameter>sampler</parameter>
                </paramdef>
                <paramdef>
                    <link xlink:href="vectorDataTypes.html">float4</link>
                    <parameter>coord</parameter>
                </paramdef>
            </funcprototype>
        </funcsynopsis>

        <funcsynopsis>
            <funcprototype>
                <funcdef>
                    <link xlink:href="vectorDataTypes.html">float4</link>
                    <function>
                        read_imagef
                    </function>
                </funcdef>
                <paramdef>
                    <link xlink:href="otherDataTypes.html">image3d_t</link>
                    <parameter>image</parameter>
                </paramdef>
                <paramdef>
                    <link xlink:href="vectorDataTypes.html">int4</link>
                    <parameter>coord</parameter>
                </paramdef>
            </funcprototype>
        </funcsynopsis>

        <bridgehead>Functions added with mipmap support enabled by extension
        <code>cl_khr_mipmap_image</code>:</bridgehead>

        <funcsynopsis>
            <funcprototype>
                <funcdef>
                    <link xlink:href="vectorDataTypes.html">float4</link>
                    <function>
                        read_imagef
                    </function>
                </funcdef>
                <paramdef>
                    <link xlink:href="otherDataTypes.html">image3d_t</link>
                    <parameter>image</parameter>
                </paramdef>
                <paramdef>
                    <link xlink:href="sampler_t.html">sampler_t</link>
                    <parameter>sampler</parameter>
                </paramdef>
                <paramdef>
                    <link xlink:href="vectorDataTypes.html">float4</link>
                    <parameter>coord</parameter>
                </paramdef>
                <paramdef>
                    <link xlink:href="scalarDataTypes.html">float</link>
                    <parameter>lod</parameter>
                </paramdef>
            </funcprototype>
        </funcsynopsis>

        <funcsynopsis>
            <funcprototype>
                <funcdef>
                    <link xlink:href="vectorDataTypes.html">float4</link>
                    <function>
                        read_imagef
                    </function>
                </funcdef>
                <paramdef>
                    <link xlink:href="otherDataTypes.html">image3d_t</link>
                    <parameter>image</parameter>
                </paramdef>
                <paramdef>
                    <link xlink:href="sampler_t.html">sampler_t</link>
                    <parameter>sampler</parameter>
                </paramdef>
                <paramdef>
                    <link xlink:href="vectorDataTypes.html">float4</link>
                    <parameter>coord</parameter>
                </paramdef>
                <paramdef>
                    <link xlink:href="vectorDataTypes.html">float4</link>
                    <parameter>gradient_x</parameter>
                </paramdef>
                <paramdef>
                    <link xlink:href="vectorDataTypes.html">float4</link>
                    <parameter>gradient_y</parameter>
                </paramdef>
            </funcprototype>
        </funcsynopsis>

    </refsynopsisdiv>

<!-- ================================ DESCRIPTION  -->

    <refsect1 id="description"><title>Description</title>
        <para>
          For the forms that take an <type>image3d_t</type>, use the coordinate <emphasis>(coord.x,
          coord.y, coord.z)</emphasis> to do an element lookup in the 3D image object specified
          by <varname>image</varname>. <emphasis>coord.w</emphasis> is ignored.
        </para>

        <para>
          The samplerless read image functions behave exactly as the corresponding read
          image functions that take integer coordinates and a sampler with filter mode
          set to <constant>CLK_FILTER_NEAREST</constant>, normalized coordinates set
          to <constant>CLK_NORMALIZED_COORDS_FALSE</constant> and addressing mode to
          <constant>CLK_ADDRESS_NONE</constant>.
        </para>

        <para>
          <function>read_imagef</function> returns floating-point values in the range
          [0.0... 1.0] for image objects created with <varname>image_channel_data_type</varname>
          set to one of the predefined packed formats or <constant>CL_UNORM_INT8</constant>
          or <constant>CL_UNORM_INT16</constant>.
        </para>

        <para>
          <function>read_imagef</function> returns floating-point values in the range [-1.0... 1.0]
          for image objects created with <varname>image_channel_data_type</varname> set to
          <constant>CL_SNORM_INT8</constant>, or <constant>CL_SNORM_INT16</constant>.
        </para>

        <para>
          <function>read_imagef</function> returns floating-point values for image objects created
          with <varname>image_channel_data_type</varname> set to <constant>CL_HALF_FLOAT</constant>
          or <constant>CL_FLOAT</constant>.
        </para>

        <para>
          The <function>read_imagef</function> calls that take integer coordinates must
          use a sampler with filter mode set to <constant>CLK_FILTER_NEAREST</constant>,
          normalized coordinates set to <constant>CLK_NORMALIZED_COORDS_FALSE</constant>
          and addressing mode set to <constant>CLK_ADDRESS_CLAMP_TO_EDGE</constant>,
          <constant>CLK_ADDRESS_CLAMP</constant> or <constant>CLK_ADDRESS_NONE</constant>;
          otherwise the values returned are undefined.
        </para>

        <para>
          Values returned by <function>read_imagef</function> for image objects with
          <varname>image_channel_data_type</varname> values not specified in the description
          above are undefined.
        </para>

        &imageMipmapFunctions3DInc;

    </refsect1>

<!-- ================================ NOTES  -->
    <refsect1 id="notes"><title>Notes</title>
        <para>
          General information about the <function>read_image</function>* functions follows.
        </para>

        &imageFunctionsInc;

        &imageMappingInc;

        <bridgehead>Mipmap read image functions:</bridgehead>

        <para>
            <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>

    </refsect1>

<!-- ================================ SPECIFICATION  -->
<!-- Set the "uri" attribute in the <olink /> element to the "named destination" for the PDF page
-->
    <refsect1 id="specification"><title>Specification</title>
        <para>
            <imageobject>
                <imagedata fileref="pdficon_small1.gif" format="gif" />
            </imageobject>

            <olink uri="imageFunctions">OpenCL Specification</olink>
        </para>
    </refsect1>

<!-- ================================ ALSO SEE  -->

    <refsect1 id="seealso"><title>Also see</title>
        <para>
            <citerefentry href="imageFunctions"><refentrytitle>Image Functions</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>cl_khr_mipmap_image</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>sampler_t</refentrytitle></citerefentry>
        </para>
    </refsect1>

<!-- ============================== COPYRIGHT -->
<!-- Content included from copyright.inc.xsl -->

    <refsect3 id="Copyright"><title></title>
        <imageobject>
                <imagedata fileref="KhronosLogo.jpg" format="jpg" />
        </imageobject>
        <para />
    </refsect3>

<!-- 19-Dec-2013, rev. 19 -->
</refentry>