| 1 | <?xml version="1.0" encoding="UTF-8"?> |
| 2 | <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN" |
| 3 | "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd"> |
| 4 | <refentry id="gluScaleImage"> |
| 5 | <refmeta> |
| 6 | <refmetainfo> |
| 7 | <copyright> |
| 8 | <year>1991-2006</year> |
| 9 | <holder>Silicon Graphics, Inc.</holder> |
| 10 | </copyright> |
| 11 | </refmetainfo> |
| 12 | <refentrytitle>gluScaleImage</refentrytitle> |
| 13 | <manvolnum>3G</manvolnum> |
| 14 | </refmeta> |
| 15 | <refnamediv> |
| 16 | <refname>gluScaleImage</refname> |
| 17 | <refpurpose>scale an image to an arbitrary size</refpurpose> |
| 18 | </refnamediv> |
| 19 | <refsynopsisdiv><title>C Specification</title> |
| 20 | <funcsynopsis> |
| 21 | <funcprototype> |
| 22 | <funcdef>GLint <function>gluScaleImage</function></funcdef> |
| 23 | <paramdef>GLenum <parameter>format</parameter></paramdef> |
| 24 | <paramdef>GLsizei <parameter>wIn</parameter></paramdef> |
| 25 | <paramdef>GLsizei <parameter>hIn</parameter></paramdef> |
| 26 | <paramdef>GLenum <parameter>typeIn</parameter></paramdef> |
| 27 | <paramdef>const void * <parameter>dataIn</parameter></paramdef> |
| 28 | <paramdef>GLsizei <parameter>wOut</parameter></paramdef> |
| 29 | <paramdef>GLsizei <parameter>hOut</parameter></paramdef> |
| 30 | <paramdef>GLenum <parameter>typeOut</parameter></paramdef> |
| 31 | <paramdef>GLvoid* <parameter>dataOut</parameter></paramdef> |
| 32 | </funcprototype> |
| 33 | </funcsynopsis> |
| 34 | </refsynopsisdiv> |
| 35 | <!-- eqn: ignoring delim $$ --> |
| 36 | <refsect1 id="parameters"><title>Parameters</title> |
| 37 | <variablelist> |
| 38 | <varlistentry> |
| 39 | <term><parameter>format</parameter></term> |
| 40 | <listitem> |
| 41 | <para> |
| 42 | Specifies the format of the pixel data. |
| 43 | The following symbolic values are valid: |
| 44 | <constant>GLU_COLOR_INDEX</constant>, |
| 45 | <constant>GLU_STENCIL_INDEX</constant>, |
| 46 | <constant>GLU_DEPTH_COMPONENT</constant>, |
| 47 | <constant>GLU_RED</constant>, |
| 48 | <constant>GLU_GREEN</constant>, |
| 49 | <constant>GLU_BLUE</constant>, |
| 50 | <constant>GLU_ALPHA</constant>, |
| 51 | <constant>GLU_RGB</constant>, |
| 52 | <constant>GLU_RGBA</constant>, |
| 53 | <constant>GLU_BGR</constant>, |
| 54 | <constant>GLU_BGRA</constant>, |
| 55 | <constant>GLU_LUMINANCE</constant>, and |
| 56 | <constant>GLU_LUMINANCE_ALPHA</constant>. |
| 57 | </para> |
| 58 | </listitem> |
| 59 | </varlistentry> |
| 60 | <varlistentry> |
| 61 | <term><parameter>wIn</parameter></term> |
| 62 | <term><parameter>hIn</parameter></term> |
| 63 | <listitem> |
| 64 | <para> |
| 65 | Specify in pixels the width and height, respectively, of the source image. |
| 66 | </para> |
| 67 | </listitem> |
| 68 | </varlistentry> |
| 69 | <varlistentry> |
| 70 | <term><parameter>typeIn</parameter></term> |
| 71 | <listitem> |
| 72 | <para> |
| 73 | Specifies the data type for <parameter>dataIn</parameter>. Must be one of |
| 74 | <constant>GLU_UNSIGNED_BYTE</constant>, |
| 75 | <constant>GLU_BYTE</constant>, |
| 76 | <constant>GLU_BITMAP</constant>, |
| 77 | <constant>GLU_UNSIGNED_SHORT</constant>, |
| 78 | <constant>GLU_SHORT</constant>, |
| 79 | <constant>GLU_UNSIGNED_INT</constant>, |
| 80 | <constant>GLU_INT</constant>, |
| 81 | <constant>GLU_FLOAT</constant>, |
| 82 | <constant>GLU_UNSIGNED_BYTE_3_3_2</constant>, |
| 83 | <constant>GLU_UNSIGNED_BYTE_2_3_3_REV</constant>, |
| 84 | <constant>GLU_UNSIGNED_SHORT_5_6_5</constant>, |
| 85 | <constant>GLU_UNSIGNED_SHORT_5_6_5_REV</constant>, |
| 86 | <constant>GLU_UNSIGNED_SHORT_4_4_4_4</constant>, |
| 87 | <constant>GLU_UNSIGNED_SHORT_4_4_4_4_REV</constant>, |
| 88 | <constant>GLU_UNSIGNED_SHORT_5_5_5_1</constant>, |
| 89 | <constant>GLU_UNSIGNED_SHORT_1_5_5_5_REV</constant>, |
| 90 | <constant>GLU_UNSIGNED_INT_8_8_8_8</constant>, |
| 91 | <constant>GLU_UNSIGNED_INT_8_8_8_8_REV</constant>, |
| 92 | <constant>GLU_UNSIGNED_INT_10_10_10_2</constant>, or |
| 93 | <constant>GLU_UNSIGNED_INT_2_10_10_10_REV</constant>. |
| 94 | </para> |
| 95 | </listitem> |
| 96 | </varlistentry> |
| 97 | <varlistentry> |
| 98 | <term><parameter>dataIn</parameter></term> |
| 99 | <listitem> |
| 100 | <para> |
| 101 | Specifies a pointer to the source image. |
| 102 | </para> |
| 103 | </listitem> |
| 104 | </varlistentry> |
| 105 | <varlistentry> |
| 106 | <term><parameter>wOut</parameter></term> |
| 107 | <term><parameter>hOut</parameter></term> |
| 108 | <listitem> |
| 109 | <para> |
| 110 | Specify the width and height, respectively, in pixels of the destination image. |
| 111 | </para> |
| 112 | </listitem> |
| 113 | </varlistentry> |
| 114 | <varlistentry> |
| 115 | <term><parameter>typeOut</parameter></term> |
| 116 | <listitem> |
| 117 | <para> |
| 118 | Specifies the data type for <parameter>dataOut</parameter>. Must be one of |
| 119 | <constant>GLU_UNSIGNED_BYTE</constant>, |
| 120 | <constant>GLU_BYTE</constant>, |
| 121 | <constant>GLU_BITMAP</constant>, |
| 122 | <constant>GLU_UNSIGNED_SHORT</constant>, |
| 123 | <constant>GLU_SHORT</constant>, |
| 124 | <constant>GLU_UNSIGNED_INT</constant>, |
| 125 | <constant>GLU_INT</constant>, |
| 126 | <constant>GLU_FLOAT</constant>, |
| 127 | <constant>GLU_UNSIGNED_BYTE_3_3_2</constant>, |
| 128 | <constant>GLU_UNSIGNED_BYTE_2_3_3_REV</constant>, |
| 129 | <constant>GLU_UNSIGNED_SHORT_5_6_5</constant>, |
| 130 | <constant>GLU_UNSIGNED_SHORT_5_6_5_REV</constant>, |
| 131 | <constant>GLU_UNSIGNED_SHORT_4_4_4_4</constant>, |
| 132 | <constant>GLU_UNSIGNED_SHORT_4_4_4_4_REV</constant>, |
| 133 | <constant>GLU_UNSIGNED_SHORT_5_5_5_1</constant>, |
| 134 | <constant>GLU_UNSIGNED_SHORT_1_5_5_5_REV</constant>, |
| 135 | <constant>GLU_UNSIGNED_INT_8_8_8_8</constant>, |
| 136 | <constant>GLU_UNSIGNED_INT_8_8_8_8_REV</constant>, |
| 137 | <constant>GLU_UNSIGNED_INT_10_10_10_2</constant>, or |
| 138 | <constant>GLU_UNSIGNED_INT_2_10_10_10_REV</constant>. |
| 139 | </para> |
| 140 | </listitem> |
| 141 | </varlistentry> |
| 142 | <varlistentry> |
| 143 | <term><parameter>dataOut</parameter></term> |
| 144 | <listitem> |
| 145 | <para> |
| 146 | Specifies a pointer to the destination image. |
| 147 | </para> |
| 148 | </listitem> |
| 149 | </varlistentry> |
| 150 | </variablelist> |
| 151 | </refsect1> |
| 152 | <refsect1 id="description"><title>Description</title> |
| 153 | <para> |
| 154 | <function>gluScaleImage</function> scales a pixel image using the appropriate pixel store modes to |
| 155 | unpack data from the source image and pack data into the destination image. |
| 156 | </para> |
| 157 | <para> |
| 158 | When shrinking an image, <function>gluScaleImage</function> uses a box filter to sample the source image |
| 159 | and create pixels for the destination image. When magnifying an image, |
| 160 | the pixels from the source image are linearly interpolated to create the |
| 161 | destination image. |
| 162 | </para> |
| 163 | <para> |
| 164 | A return value of zero indicates success, otherwise a GLU error code is returned (see <citerefentry><refentrytitle>gluErrorString</refentrytitle></citerefentry>). |
| 165 | </para> |
| 166 | <para> |
| 167 | See the <citerefentry><refentrytitle>glReadPixels</refentrytitle></citerefentry> reference page for a description of |
| 168 | the acceptable values for the <parameter>format</parameter>, <parameter>typeIn</parameter>, and <parameter>typeOut</parameter> parameters. |
| 169 | </para> |
| 170 | </refsect1> |
| 171 | <refsect1 id="notes"><title>Notes</title> |
| 172 | <para> |
| 173 | Formats <constant>GLU_BGR</constant>, and <constant>GLU_BGRA</constant>, and types |
| 174 | <constant>GLU_UNSIGNED_BYTE_3_3_2</constant>, |
| 175 | <constant>GLU_UNSIGNED_BYTE_2_3_3_REV</constant>, |
| 176 | <constant>GLU_UNSIGNED_SHORT_5_6_5</constant>, |
| 177 | <constant>GLU_UNSIGNED_SHORT_5_6_5_REV</constant>, |
| 178 | <constant>GLU_UNSIGNED_SHORT_4_4_4_4</constant>, |
| 179 | <constant>GLU_UNSIGNED_SHORT_4_4_4_4_REV</constant>, |
| 180 | <constant>GLU_UNSIGNED_SHORT_5_5_5_1</constant>, |
| 181 | <constant>GLU_UNSIGNED_SHORT_1_5_5_5_REV</constant>, |
| 182 | <constant>GLU_UNSIGNED_INT_8_8_8_8</constant>, |
| 183 | <constant>GLU_UNSIGNED_INT_8_8_8_8_REV</constant>, |
| 184 | <constant>GLU_UNSIGNED_INT_10_10_10_2</constant>, and |
| 185 | <constant>GLU_UNSIGNED_INT_2_10_10_10_REV</constant> are only available if the GL version |
| 186 | is 1.2 or greater. |
| 187 | </para> |
| 188 | </refsect1> |
| 189 | <refsect1 id="errors"><title>Errors</title> |
| 190 | <para> |
| 191 | <constant>GLU_INVALID_VALUE</constant> is returned if <parameter>wIn</parameter>, <parameter>hIn</parameter>, <parameter>wOut</parameter>, or <parameter>hOut</parameter> |
| 192 | is negative. |
| 193 | </para> |
| 194 | <para> |
| 195 | <constant>GLU_INVALID_ENUM</constant> is returned if <parameter>format</parameter>, <parameter>typeIn</parameter>, or <parameter>typeOut</parameter> is not |
| 196 | legal. |
| 197 | </para> |
| 198 | <para> |
| 199 | <constant>GLU_INVALID_OPERATION</constant> is returned if <parameter>typeIn</parameter> or <parameter>typeOut</parameter> is |
| 200 | <constant>GLU_UNSIGNED_BYTE_3_3_2</constant> or <constant>GLU_UNSIGNED_BYTE_2_3_3_REV</constant> |
| 201 | and <parameter>format</parameter> is not <constant>GLU_RGB</constant>. |
| 202 | </para> |
| 203 | <para> |
| 204 | <constant>GLU_INVALID_OPERATION</constant> is returned if <parameter>typeIn</parameter> or <parameter>typeOut</parameter> is |
| 205 | <constant>GLU_UNSIGNED_SHORT_5_6_5</constant> or <constant>GLU_UNSIGNED_SHORT_5_6_5_REV</constant> |
| 206 | and <parameter>format</parameter> is not <constant>GLU_RGB</constant>. |
| 207 | </para> |
| 208 | <para> |
| 209 | <constant>GLU_INVALID_OPERATION</constant> is returned if <parameter>typeIn</parameter> or <parameter>typeOut</parameter> is |
| 210 | <constant>GLU_UNSIGNED_SHORT_4_4_4_4</constant> or <constant>GLU_UNSIGNED_SHORT_4_4_4_4_REV</constant> |
| 211 | and <parameter>format</parameter> is neither <constant>GLU_RGBA</constant> nor <constant>GLU_BGRA</constant>. |
| 212 | </para> |
| 213 | <para> |
| 214 | <constant>GLU_INVALID_OPERATION</constant> is returned if <parameter>typeIn</parameter> or <parameter>typeOut</parameter> is |
| 215 | <constant>GLU_UNSIGNED_SHORT_5_5_5_1</constant> or <constant>GLU_UNSIGNED_SHORT_1_5_5_5_REV</constant> |
| 216 | and <parameter>format</parameter> is neither <constant>GLU_RGBA</constant> nor <constant>GLU_BGRA</constant>. |
| 217 | </para> |
| 218 | <para> |
| 219 | <constant>GLU_INVALID_OPERATION</constant> is returned if <parameter>typeIn</parameter> or <parameter>typeOut</parameter> is |
| 220 | <constant>GLU_UNSIGNED_INT_8_8_8_8</constant> or <constant>GLU_UNSIGNED_INT_8_8_8_8_REV</constant> |
| 221 | and <parameter>format</parameter> is neither <constant>GLU_RGBA</constant> nor <constant>GLU_BGRA</constant>. |
| 222 | </para> |
| 223 | <para> |
| 224 | <constant>GLU_INVALID_OPERATION</constant> is returned if <parameter>typeIn</parameter> or <parameter>typeOut</parameter> is |
| 225 | <constant>GLU_UNSIGNED_INT_10_10_10_2</constant> or <constant>GLU_UNSIGNED_INT_2_10_10_10_REV</constant> |
| 226 | and <parameter>format</parameter> is neither <constant>GLU_RGBA</constant> nor <constant>GLU_BGRA</constant>. |
| 227 | </para> |
| 228 | </refsect1> |
| 229 | <refsect1 id="seealso"><title>See Also</title> |
| 230 | <para> |
| 231 | <citerefentry><refentrytitle>gluBuild1DMipmaps</refentrytitle></citerefentry>, |
| 232 | <citerefentry><refentrytitle>gluBuild2DMipmaps</refentrytitle></citerefentry>, |
| 233 | <citerefentry><refentrytitle>gluBuild3DMipmaps</refentrytitle></citerefentry>, |
| 234 | <citerefentry><refentrytitle>gluErrorString</refentrytitle></citerefentry>, |
| 235 | <citerefentry><refentrytitle>glDrawPixels</refentrytitle></citerefentry>, |
| 236 | <citerefentry><refentrytitle>glReadPixels</refentrytitle></citerefentry> |
| 237 | </para> |
| 238 | </refsect1> |
| 239 | <refsect1 id="Copyright"><title>Copyright</title> |
| 240 | <para> |
| 241 | Copyright <trademark class="copyright"></trademark> 1991-2006 |
| 242 | Silicon Graphics, Inc. This document is licensed under the SGI |
| 243 | Free Software B License. For details, see |
| 244 | <ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>. |
| 245 | </para> |
| 246 | </refsect1> |
| 247 | </refentry> |