upstream-doc/man3/glVertexAttrib.xml

   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="glVertexAttrib">
   5     <refmeta>
   6     <refentrytitle>glVertexAttrib</refentrytitle>
   7     <manvolnum>3G</manvolnum>
   8     </refmeta>
   9     <refnamediv>
  10     <refname>glVertexAttrib</refname>
  11     <refpurpose>Specifies the value of a generic vertex attribute</refpurpose>
  12     </refnamediv>
  13     <refsynopsisdiv><title>C Specification</title>
  14     <funcsynopsis>
  15         <funcprototype>
  16         <funcdef>void <function>glVertexAttrib1f</function></funcdef>
  17         <paramdef>GLuint <parameter>index</parameter></paramdef>
  18         <paramdef>GLfloat <parameter>v0</parameter></paramdef>
  19         </funcprototype>
  20         <funcprototype>
  21         <funcdef>void <function>glVertexAttrib1s</function></funcdef>
  22         <paramdef>GLuint <parameter>index</parameter></paramdef>
  23         <paramdef>GLshort <parameter>v0</parameter></paramdef>
  24         </funcprototype>
  25         <funcprototype>
  26         <funcdef>void <function>glVertexAttrib1d</function></funcdef>
  27         <paramdef>GLuint <parameter>index</parameter></paramdef>
  28         <paramdef>GLdouble <parameter>v0</parameter></paramdef>
  29         </funcprototype>
  30         <funcprototype>
  31         <funcdef>void <function>glVertexAttribI1i</function></funcdef>
  32         <paramdef>GLuint <parameter>index</parameter></paramdef>
  33         <paramdef>GLint <parameter>v0</parameter></paramdef>
  34         </funcprototype>
  35         <funcprototype>
  36         <funcdef>void <function>glVertexAttribI1ui</function></funcdef>
  37         <paramdef>GLuint <parameter>index</parameter></paramdef>
  38         <paramdef>GLuint <parameter>v0</parameter></paramdef>
  39         </funcprototype>
  40         <funcprototype>
  41         <funcdef>void <function>glVertexAttrib2f</function></funcdef>
  42         <paramdef>GLuint <parameter>index</parameter></paramdef>
  43         <paramdef>GLfloat <parameter>v0</parameter></paramdef>
  44         <paramdef>GLfloat <parameter>v1</parameter></paramdef>
  45         </funcprototype>
  46         <funcprototype>
  47         <funcdef>void <function>glVertexAttrib2s</function></funcdef>
  48         <paramdef>GLuint <parameter>index</parameter></paramdef>
  49         <paramdef>GLshort <parameter>v0</parameter></paramdef>
  50         <paramdef>GLshort <parameter>v1</parameter></paramdef>
  51         </funcprototype>
  52         <funcprototype>
  53         <funcdef>void <function>glVertexAttrib2d</function></funcdef>
  54         <paramdef>GLuint <parameter>index</parameter></paramdef>
  55         <paramdef>GLdouble <parameter>v0</parameter></paramdef>
  56         <paramdef>GLdouble <parameter>v1</parameter></paramdef>
  57         </funcprototype>
  58         <funcprototype>
  59         <funcdef>void <function>glVertexAttribI2i</function></funcdef>
  60         <paramdef>GLuint <parameter>index</parameter></paramdef>
  61         <paramdef>GLint <parameter>v0</parameter></paramdef>
  62         <paramdef>GLint <parameter>v1</parameter></paramdef>
  63         </funcprototype>
  64         <funcprototype>
  65         <funcdef>void <function>glVertexAttribI2ui</function></funcdef>
  66         <paramdef>GLuint <parameter>index</parameter></paramdef>
  67         <paramdef>GLuint <parameter>v0</parameter></paramdef>
  68         <paramdef>GLuint <parameter>v1</parameter></paramdef>
  69         </funcprototype>
  70         <funcprototype>
  71         <funcdef>void <function>glVertexAttrib3f</function></funcdef>
  72         <paramdef>GLuint <parameter>index</parameter></paramdef>
  73         <paramdef>GLfloat <parameter>v0</parameter></paramdef>
  74         <paramdef>GLfloat <parameter>v1</parameter></paramdef>
  75         <paramdef>GLfloat <parameter>v2</parameter></paramdef>
  76         </funcprototype>
  77         <funcprototype>
  78         <funcdef>void <function>glVertexAttrib3s</function></funcdef>
  79         <paramdef>GLuint <parameter>index</parameter></paramdef>
  80         <paramdef>GLshort <parameter>v0</parameter></paramdef>
  81         <paramdef>GLshort <parameter>v1</parameter></paramdef>
  82         <paramdef>GLshort <parameter>v2</parameter></paramdef>
  83         </funcprototype>
  84         <funcprototype>
  85         <funcdef>void <function>glVertexAttrib3d</function></funcdef>
  86         <paramdef>GLuint <parameter>index</parameter></paramdef>
  87         <paramdef>GLdouble <parameter>v0</parameter></paramdef>
  88         <paramdef>GLdouble <parameter>v1</parameter></paramdef>
  89         <paramdef>GLdouble <parameter>v2</parameter></paramdef>
  90         </funcprototype>
  91         <funcprototype>
  92         <funcdef>void <function>glVertexAttribI3i</function></funcdef>
  93         <paramdef>GLuint <parameter>index</parameter></paramdef>
  94         <paramdef>GLint <parameter>v0</parameter></paramdef>
  95         <paramdef>GLint <parameter>v1</parameter></paramdef>
  96         <paramdef>GLint <parameter>v2</parameter></paramdef>
  97         </funcprototype>
  98         <funcprototype>
  99         <funcdef>void <function>glVertexAttribI3ui</function></funcdef>
 100         <paramdef>GLuint <parameter>index</parameter></paramdef>
 101         <paramdef>GLoint <parameter>v0</parameter></paramdef>
 102         <paramdef>GLoint <parameter>v1</parameter></paramdef>
 103         <paramdef>GLoint <parameter>v2</parameter></paramdef>
 104         </funcprototype>
 105         <funcprototype>
 106         <funcdef>void <function>glVertexAttrib4f</function></funcdef>
 107         <paramdef>GLuint <parameter>index</parameter></paramdef>
 108         <paramdef>GLfloat <parameter>v0</parameter></paramdef>
 109         <paramdef>GLfloat <parameter>v1</parameter></paramdef>
 110         <paramdef>GLfloat <parameter>v2</parameter></paramdef>
 111         <paramdef>GLfloat <parameter>v3</parameter></paramdef>
 112         </funcprototype>
 113         <funcprototype>
 114         <funcdef>void <function>glVertexAttrib4s</function></funcdef>
 115         <paramdef>GLuint <parameter>index</parameter></paramdef>
 116         <paramdef>GLshort <parameter>v0</parameter></paramdef>
 117         <paramdef>GLshort <parameter>v1</parameter></paramdef>
 118         <paramdef>GLshort <parameter>v2</parameter></paramdef>
 119         <paramdef>GLshort <parameter>v3</parameter></paramdef>
 120         </funcprototype>
 121         <funcprototype>
 122         <funcdef>void <function>glVertexAttrib4d</function></funcdef>
 123         <paramdef>GLuint <parameter>index</parameter></paramdef>
 124         <paramdef>GLdouble <parameter>v0</parameter></paramdef>
 125         <paramdef>GLdouble <parameter>v1</parameter></paramdef>
 126         <paramdef>GLdouble <parameter>v2</parameter></paramdef>
 127         <paramdef>GLdouble <parameter>v3</parameter></paramdef>
 128         </funcprototype>
 129         <funcprototype>
 130         <funcdef>void <function>glVertexAttrib4Nub</function></funcdef>
 131         <paramdef>GLuint <parameter>index</parameter></paramdef>
 132         <paramdef>GLubyte <parameter>v0</parameter></paramdef>
 133         <paramdef>GLubyte <parameter>v1</parameter></paramdef>
 134         <paramdef>GLubyte <parameter>v2</parameter></paramdef>
 135         <paramdef>GLubyte <parameter>v3</parameter></paramdef>
 136         </funcprototype>
 137         <funcprototype>
 138         <funcdef>void <function>glVertexAttribI4i</function></funcdef>
 139         <paramdef>GLuint <parameter>index</parameter></paramdef>
 140         <paramdef>GLint <parameter>v0</parameter></paramdef>
 141         <paramdef>GLint <parameter>v1</parameter></paramdef>
 142         <paramdef>GLint <parameter>v2</parameter></paramdef>
 143         <paramdef>GLint <parameter>v3</parameter></paramdef>
 144         </funcprototype>
 145         <funcprototype>
 146         <funcdef>void <function>glVertexAttribI4ui</function></funcdef>
 147         <paramdef>GLuint <parameter>index</parameter></paramdef>
 148         <paramdef>GLuint <parameter>v0</parameter></paramdef>
 149         <paramdef>GLuint <parameter>v1</parameter></paramdef>
 150         <paramdef>GLuint <parameter>v2</parameter></paramdef>
 151         <paramdef>GLuint <parameter>v3</parameter></paramdef>
 152         </funcprototype>
 153     </funcsynopsis>
 154     </refsynopsisdiv>
 155     <refsect1 id="parameters"><title>Parameters</title>
 156     <variablelist>
 157         <varlistentry>
 158         <term><parameter>index</parameter></term>
 159         <listitem>
 160             <para>Specifies the index of the generic vertex
 161             attribute to be modified.</para>
 162         </listitem>
 163         </varlistentry>
 164         <varlistentry>
 165         <term>
 166             <parameter>v0</parameter>,
 167             <parameter>v1</parameter>,
 168             <parameter>v2</parameter>,
 169             <parameter>v3</parameter>
 170         </term>
 171         <listitem>
 172             <para>Specifies the new values to be used for the
 173             specified vertex attribute.</para>
 174         </listitem>
 175         </varlistentry>
 176     </variablelist>
 177     </refsect1>
 178     <refsynopsisdiv><title>C Specification</title>
 179     <funcsynopsis>
 180         <funcprototype>
 181         <funcdef>void <function>glVertexAttrib1fv</function></funcdef>
 182         <paramdef>GLuint <parameter>index</parameter></paramdef>
 183         <paramdef>const GLfloat *<parameter>v</parameter></paramdef>
 184         </funcprototype>
 185         <funcprototype>
 186         <funcdef>void <function>glVertexAttrib1sv</function></funcdef>
 187         <paramdef>GLuint <parameter>index</parameter></paramdef>
 188         <paramdef>const GLshort *<parameter>v</parameter></paramdef>
 189         </funcprototype>
 190         <funcprototype>
 191         <funcdef>void <function>glVertexAttrib1dv</function></funcdef>
 192         <paramdef>GLuint <parameter>index</parameter></paramdef>
 193         <paramdef>const GLdouble *<parameter>v</parameter></paramdef>
 194         </funcprototype>
 195         <funcprototype>
 196         <funcdef>void <function>glVertexAttribI1iv</function></funcdef>
 197         <paramdef>GLuint <parameter>index</parameter></paramdef>
 198         <paramdef>const GLint *<parameter>v</parameter></paramdef>
 199         </funcprototype>
 200         <funcprototype>
 201         <funcdef>void <function>glVertexAttribI1uiv</function></funcdef>
 202         <paramdef>GLuint <parameter>index</parameter></paramdef>
 203         <paramdef>const GLuint *<parameter>v</parameter></paramdef>
 204         </funcprototype>
 205         <funcprototype>
 206         <funcdef>void <function>glVertexAttrib2fv</function></funcdef>
 207         <paramdef>GLuint <parameter>index</parameter></paramdef>
 208         <paramdef>const GLfloat *<parameter>v</parameter></paramdef>
 209         </funcprototype>
 210         <funcprototype>
 211         <funcdef>void <function>glVertexAttrib2sv</function></funcdef>
 212         <paramdef>GLuint <parameter>index</parameter></paramdef>
 213         <paramdef>const GLshort *<parameter>v</parameter></paramdef>
 214         </funcprototype>
 215         <funcprototype>
 216         <funcdef>void <function>glVertexAttrib2dv</function></funcdef>
 217         <paramdef>GLuint <parameter>index</parameter></paramdef>
 218         <paramdef>const GLdouble *<parameter>v</parameter></paramdef>
 219         </funcprototype>
 220         <funcprototype>
 221         <funcdef>void <function>glVertexAttribI2iv</function></funcdef>
 222         <paramdef>GLuint <parameter>index</parameter></paramdef>
 223         <paramdef>const GLint *<parameter>v</parameter></paramdef>
 224         </funcprototype>
 225         <funcprototype>
 226         <funcdef>void <function>glVertexAttribI2uiv</function></funcdef>
 227         <paramdef>GLuint <parameter>index</parameter></paramdef>
 228         <paramdef>const GLuint *<parameter>v</parameter></paramdef>
 229         </funcprototype>
 230         <funcprototype>
 231         <funcdef>void <function>glVertexAttrib3fv</function></funcdef>
 232         <paramdef>GLuint <parameter>index</parameter></paramdef>
 233         <paramdef>const GLfloat *<parameter>v</parameter></paramdef>
 234         </funcprototype>
 235         <funcprototype>
 236         <funcdef>void <function>glVertexAttrib3sv</function></funcdef>
 237         <paramdef>GLuint <parameter>index</parameter></paramdef>
 238         <paramdef>const GLshort *<parameter>v</parameter></paramdef>
 239         </funcprototype>
 240         <funcprototype>
 241         <funcdef>void <function>glVertexAttrib3dv</function></funcdef>
 242         <paramdef>GLuint <parameter>index</parameter></paramdef>
 243         <paramdef>const GLdouble *<parameter>v</parameter></paramdef>
 244         </funcprototype>
 245         <funcprototype>
 246         <funcdef>void <function>glVertexAttribI3iv</function></funcdef>
 247         <paramdef>GLuint <parameter>index</parameter></paramdef>
 248         <paramdef>const GLint *<parameter>v</parameter></paramdef>
 249         </funcprototype>
 250         <funcprototype>
 251         <funcdef>void <function>glVertexAttribI3uiv</function></funcdef>
 252         <paramdef>GLuint <parameter>index</parameter></paramdef>
 253         <paramdef>const GLuint *<parameter>v</parameter></paramdef>
 254         </funcprototype>
 255         <funcprototype>
 256         <funcdef>void <function>glVertexAttrib4fv</function></funcdef>
 257         <paramdef>GLuint <parameter>index</parameter></paramdef>
 258         <paramdef>const GLfloat *<parameter>v</parameter></paramdef>
 259         </funcprototype>
 260         <funcprototype>
 261         <funcdef>void <function>glVertexAttrib4sv</function></funcdef>
 262         <paramdef>GLuint <parameter>index</parameter></paramdef>
 263         <paramdef>const GLshort *<parameter>v</parameter></paramdef>
 264         </funcprototype>
 265         <funcprototype>
 266         <funcdef>void <function>glVertexAttrib4dv</function></funcdef>
 267         <paramdef>GLuint <parameter>index</parameter></paramdef>
 268         <paramdef>const GLdouble *<parameter>v</parameter></paramdef>
 269         </funcprototype>
 270         <funcprototype>
 271         <funcdef>void <function>glVertexAttrib4iv</function></funcdef>
 272         <paramdef>GLuint <parameter>index</parameter></paramdef>
 273         <paramdef>const GLint *<parameter>v</parameter></paramdef>
 274         </funcprototype>
 275         <funcprototype>
 276         <funcdef>void <function>glVertexAttrib4bv</function></funcdef>
 277         <paramdef>GLuint <parameter>index</parameter></paramdef>
 278         <paramdef>const GLbyte *<parameter>v</parameter></paramdef>
 279         </funcprototype>
 280         <funcprototype>
 281         <funcdef>void <function>glVertexAttrib4ubv</function></funcdef>
 282         <paramdef>GLuint <parameter>index</parameter></paramdef>
 283         <paramdef>const GLubyte *<parameter>v</parameter></paramdef>
 284         </funcprototype>
 285         <funcprototype>
 286         <funcdef>void <function>glVertexAttrib4usv</function></funcdef>
 287         <paramdef>GLuint <parameter>index</parameter></paramdef>
 288         <paramdef>const GLushort *<parameter>v</parameter></paramdef>
 289         </funcprototype>
 290         <funcprototype>
 291         <funcdef>void <function>glVertexAttrib4uiv</function></funcdef>
 292         <paramdef>GLuint <parameter>index</parameter></paramdef>
 293         <paramdef>const GLuint *<parameter>v</parameter></paramdef>
 294         </funcprototype>
 295         <funcprototype>
 296         <funcdef>void <function>glVertexAttrib4Nbv</function></funcdef>
 297         <paramdef>GLuint <parameter>index</parameter></paramdef>
 298         <paramdef>const GLbyte *<parameter>v</parameter></paramdef>
 299         </funcprototype>
 300         <funcprototype>
 301         <funcdef>void <function>glVertexAttrib4Nsv</function></funcdef>
 302         <paramdef>GLuint <parameter>index</parameter></paramdef>
 303         <paramdef>const GLshort *<parameter>v</parameter></paramdef>
 304         </funcprototype>
 305         <funcprototype>
 306         <funcdef>void <function>glVertexAttrib4Niv</function></funcdef>
 307         <paramdef>GLuint <parameter>index</parameter></paramdef>
 308         <paramdef>const GLint *<parameter>v</parameter></paramdef>
 309         </funcprototype>
 310         <funcprototype>
 311         <funcdef>void <function>glVertexAttrib4Nubv</function></funcdef>
 312         <paramdef>GLuint <parameter>index</parameter></paramdef>
 313         <paramdef>const GLubyte *<parameter>v</parameter></paramdef>
 314         </funcprototype>
 315         <funcprototype>
 316         <funcdef>void <function>glVertexAttrib4Nusv</function></funcdef>
 317         <paramdef>GLuint <parameter>index</parameter></paramdef>
 318         <paramdef>const GLushort *<parameter>v</parameter></paramdef>
 319         </funcprototype>
 320         <funcprototype>
 321         <funcdef>void <function>glVertexAttrib4Nuiv</function></funcdef>
 322         <paramdef>GLuint <parameter>index</parameter></paramdef>
 323         <paramdef>const GLuint *<parameter>v</parameter></paramdef>
 324         </funcprototype>
 325         <funcprototype>
 326         <funcdef>void <function>glVertexAttribI4bv</function></funcdef>
 327         <paramdef>GLuint <parameter>index</parameter></paramdef>
 328         <paramdef>const GLbyte *<parameter>v</parameter></paramdef>
 329         </funcprototype>
 330         <funcprototype>
 331         <funcdef>void <function>glVertexAttribI4ubv</function></funcdef>
 332         <paramdef>GLuint <parameter>index</parameter></paramdef>
 333         <paramdef>const GLubyte *<parameter>v</parameter></paramdef>
 334         </funcprototype>
 335         <funcprototype>
 336         <funcdef>void <function>glVertexAttribI4sv</function></funcdef>
 337         <paramdef>GLuint <parameter>index</parameter></paramdef>
 338         <paramdef>const GLshort *<parameter>v</parameter></paramdef>
 339         </funcprototype>
 340         <funcprototype>
 341         <funcdef>void <function>glVertexAttribI4usv</function></funcdef>
 342         <paramdef>GLuint <parameter>index</parameter></paramdef>
 343         <paramdef>const GLushort *<parameter>v</parameter></paramdef>
 344         </funcprototype>
 345         <funcprototype>
 346         <funcdef>void <function>glVertexAttribI4iv</function></funcdef>
 347         <paramdef>GLuint <parameter>index</parameter></paramdef>
 348         <paramdef>const GLint *<parameter>v</parameter></paramdef>
 349         </funcprototype>
 350         <funcprototype>
 351         <funcdef>void <function>glVertexAttribI4uiv</function></funcdef>
 352         <paramdef>GLuint <parameter>index</parameter></paramdef>
 353         <paramdef>const GLuint *<parameter>v</parameter></paramdef>
 354         </funcprototype>
 355     </funcsynopsis>
 356     </refsynopsisdiv>
 357     <refsect1 id="parameters2"><title>Parameters</title>
 358     <variablelist>
 359         <varlistentry>
 360         <term><parameter>index</parameter></term>
 361         <listitem>
 362             <para>Specifies the index of the generic vertex
 363             attribute to be modified.</para>
 364         </listitem>
 365         </varlistentry>
 366         <varlistentry>
 367         <term><parameter>v</parameter></term>
 368         <listitem>
 369             <para>Specifies a pointer to an array of values to
 370             be used for the generic vertex attribute.</para>
 371         </listitem>
 372         </varlistentry>
 373     </variablelist>
 374     </refsect1>
 375     <refsynopsisdiv><title>C Specification</title>
 376     <funcsynopsis>
 377         <funcprototype>
 378         <funcdef>void <function>glVertexAttribP1ui</function></funcdef>
 379         <paramdef>GLuint <parameter>index</parameter></paramdef>
 380         <paramdef>GLenum <parameter>type</parameter></paramdef>
 381         <paramdef>GLboolean <parameter>normalized</parameter></paramdef>
 382         <paramdef>GLuint <parameter>value</parameter></paramdef>
 383         </funcprototype>
 384         <funcprototype>
 385         <funcdef>void <function>glVertexAttribP2ui</function></funcdef>
 386         <paramdef>GLuint <parameter>index</parameter></paramdef>
 387         <paramdef>GLenum <parameter>type</parameter></paramdef>
 388         <paramdef>GLboolean <parameter>normalized</parameter></paramdef>
 389         <paramdef>GLuint <parameter>value</parameter></paramdef>
 390         </funcprototype>
 391         <funcprototype>
 392         <funcdef>void <function>glVertexAttribP3ui</function></funcdef>
 393         <paramdef>GLuint <parameter>index</parameter></paramdef>
 394         <paramdef>GLenum <parameter>type</parameter></paramdef>
 395         <paramdef>GLboolean <parameter>normalized</parameter></paramdef>
 396         <paramdef>GLuint <parameter>value</parameter></paramdef>
 397         </funcprototype>
 398         <funcprototype>
 399         <funcdef>void <function>glVertexAttribP4ui</function></funcdef>
 400         <paramdef>GLuint <parameter>index</parameter></paramdef>
 401         <paramdef>GLenum <parameter>type</parameter></paramdef>
 402         <paramdef>GLboolean <parameter>normalized</parameter></paramdef>
 403         <paramdef>GLuint <parameter>value</parameter></paramdef>
 404         </funcprototype>
 405     </funcsynopsis>
 406     </refsynopsisdiv>
 407     <refsect1 id="parameters3"><title>Parameters</title>
 408     <variablelist>
 409         <varlistentry>
 410         <term><parameter>index</parameter></term>
 411         <listitem>
 412             <para>Specifies the index of the generic vertex
 413             attribute to be modified.</para>
 414         </listitem>
 415         </varlistentry>
 416         <varlistentry>
 417         <term><parameter>type</parameter></term>
 418         <listitem>
 419             <para>Type of packing used on the data. This parameter must be
 420                     <constant>GL_INT_10_10_10_2</constant> or <constant>GL_UNSIGNED_INT_10_10_10_2</constant>
 421                     to specify signed or unsigned data, respectively.</para>
 422         </listitem>
 423         </varlistentry>
 424         <varlistentry>
 425         <term><parameter>normalized</parameter></term>
 426         <listitem>
 427             <para>If <constant>GL_TRUE</constant>, then the values are to be
 428                     converted to floating point values by normalizing. Otherwise,
 429                     they are converted directly to floating point values.</para>
 430         </listitem>
 431         </varlistentry>
 432         <varlistentry>
 433         <term>
 434             <parameter>value</parameter>
 435         </term>
 436         <listitem>
 437             <para>Specifies the new packed value to be used for the
 438             specified vertex attribute.</para>
 439         </listitem>
 440         </varlistentry>
 441     </variablelist>
 442     </refsect1>
 443     <refsect1 id="description"><title>Description</title>
 444     <para>OpenGL defines a number of standard vertex attributes that
 445     applications can modify with standard API entry points (color,
 446     normal, texture coordinates, etc.). The
 447     <function>glVertexAttrib</function> family of entry points
 448     allows an application to pass generic vertex attributes in
 449     numbered locations.</para>
 450
 451     <para>Generic attributes are defined as four-component values
 452     that are organized into an array. The first entry of this array
 453     is numbered 0, and the size of the array is specified by the
 454     implementation-dependent constant
 455     <constant>GL_MAX_VERTEX_ATTRIBS</constant>. Individual elements
 456     of this array can be modified with a
 457     <function>glVertexAttrib</function> call that specifies the
 458     index of the element to be modified and a value for that
 459     element.</para>
 460
 461     <para>These commands can be used to specify one, two, three, or
 462     all four components of the generic vertex attribute specified by
 463     <parameter>index</parameter>. A <function>1</function> in the
 464     name of the command indicates that only one value is passed, and
 465     it will be used to modify the first component of the generic
 466     vertex attribute. The second and third components will be set to
 467     0, and the fourth component will be set to 1. Similarly, a
 468     <function>2</function> in the name of the command indicates that
 469     values are provided for the first two components, the third
 470     component will be set to 0, and the fourth component will be set
 471     to 1. A <function>3</function> in the name of the command
 472     indicates that values are provided for the first three
 473     components and the fourth component will be set to 1, whereas a
 474     <function>4</function> in the name indicates that values are
 475     provided for all four components.</para>
 476
 477     <para>The letters <function>s</function>,
 478     <function>f</function>, <function>i</function>,
 479     <function>d</function>, <function>ub</function>,
 480     <function>us</function>, and <function>ui</function> indicate
 481     whether the arguments are of type short, float, int, double,
 482     unsigned byte, unsigned short, or unsigned int. When
 483     <function>v</function> is appended to the name, the commands can
 484     take a pointer to an array of such values.</para>
 485
 486         <para>Additional capitalized letters can indicate further alterations
 487         to the default behavior of the glVertexAttrib function:</para>
 488
 489         <para>
 490             The commands containing <function>N</function> indicate that
 491             the arguments will be passed as fixed-point values that are
 492             scaled to a normalized range according to the component
 493             conversion rules defined by the OpenGL specification. Signed
 494             values are understood to represent fixed-point values in the
 495             range [-1,1], and unsigned values are understood to represent
 496             fixed-point values in the range [0,1].
 497         </para>
 498
 499         <para>
 500             The commands containing <function>I</function> indicate that
 501             the arguments are extended to full signed or unsigned integers.
 502         </para>
 503
 504         <para>
 505             The commands containing <function>P</function> indicate that
 506             the arguments are stored as packed components within a larger
 507             natural type.
 508         </para>
 509
 510     <para>OpenGL Shading Language attribute variables are allowed to
 511     be of type mat2, mat3, or mat4. Attributes of these types may be
 512     loaded using the <function>glVertexAttrib</function> entry
 513     points. Matrices must be loaded into successive generic
 514     attribute slots in column major order, with one column of the
 515     matrix in each generic attribute slot.</para>
 516
 517     <para>A user-defined attribute variable declared in a vertex
 518     shader can be bound to a generic attribute index by calling
 519     <citerefentry><refentrytitle>glBindAttribLocation</refentrytitle></citerefentry>.
 520     This allows an application to use more descriptive variable
 521     names in a vertex shader. A subsequent change to the specified
 522     generic vertex attribute will be immediately reflected as a
 523     change to the corresponding attribute variable in the vertex
 524     shader.</para>
 525
 526     <para>The binding between a generic vertex attribute index and a
 527     user-defined attribute variable in a vertex shader is part of
 528     the state of a program object, but the current value of the
 529     generic vertex attribute is not. The value of each generic
 530     vertex attribute is part of current state, just like standard
 531     vertex attributes, and it is maintained even if a different
 532     program object is used.</para>
 533
 534     <para>An application may freely modify generic vertex attributes
 535     that are not bound to a named vertex shader attribute variable.
 536     These values are simply maintained as part of current state and
 537     will not be accessed by the vertex shader. If a generic vertex
 538     attribute bound to an attribute variable in a vertex shader is
 539     not updated while the vertex shader is executing, the vertex
 540     shader will repeatedly use the current value for the generic
 541     vertex attribute.</para>
 542     </refsect1>
 543     <refsect1 id="notes"><title>Notes</title>
 544     <para>Generic vertex attributes can be updated at any time.</para>
 545
 546     <para>It is possible for an application to bind more than one
 547     attribute name to the same generic vertex attribute index. This
 548     is referred to as aliasing, and it is allowed only if just one
 549     of the aliased attribute variables is active in the vertex
 550     shader, or if no path through the vertex shader consumes more
 551     than one of the attributes aliased to the same location. OpenGL
 552     implementations are not required to do error checking to detect
 553     aliasing, they are allowed to assume that aliasing will not
 554     occur, and they are allowed to employ optimizations that work
 555     only in the absence of aliasing.</para>
 556
 557     <para>There is no provision for binding standard vertex
 558     attributes; therefore, it is not possible to alias generic
 559     attributes with standard attributes.</para>
 560
 561         <para>
 562             <function>glVertexAttrib4bv</function>, <function>glVertexAttrib4sv</function>,
 563             <function>glVertexAttrib4iv</function>, <function>glVertexAttrib4ubv</function>,
 564             <function>glVertexAttrib4usv</function>, <function>glVertexAttrib4uiv</function>, and
 565             <function>glVertexAttrib4N</function> versions are available only if the GL version is 3.1 or higher.
 566         </para>
 567
 568         <para>
 569             <function>glVertexAttribP</function> versions are available only if the GL version is 3.3 or higher.
 570         </para>
 571     </refsect1>
 572     <refsect1 id="errors"><title>Errors</title>
 573     <para><constant>GL_INVALID_VALUE</constant> is generated if
 574     <parameter>index</parameter> is greater than or equal to
 575     <constant>GL_MAX_VERTEX_ATTRIBS</constant>.</para>
 576
 577     <para><constant>GL_INVALID_ENUM</constant> is generated if
 578     <function>glVertexAttribP</function> is used with a
 579         <parameter>type</parameter> other than
 580     <constant>GL_INT_10_10_10_2</constant> or
 581         <constant>GL_UNSIGNED_INT_10_10_10_2</constant>.</para>
 582     </refsect1>
 583     <refsect1 id="associatedgets"><title>Associated Gets</title>
 584     <para><citerefentry><refentrytitle>glGet</refentrytitle></citerefentry>
 585     with the argument <constant>GL_CURRENT_PROGRAM</constant></para>
 586
 587     <para><citerefentry><refentrytitle>glGetActiveAttrib</refentrytitle></citerefentry>
 588     with argument <parameter>program</parameter> and the index of an active
 589     attribute variable</para>
 590
 591     <para><citerefentry><refentrytitle>glGetAttribLocation</refentrytitle></citerefentry>
 592     with argument <parameter>program</parameter> and an attribute
 593     variable name</para>
 594
 595     <para><citerefentry><refentrytitle>glGetVertexAttrib</refentrytitle></citerefentry>
 596     with arguments <constant>GL_CURRENT_VERTEX_ATTRIB</constant> and
 597     <parameter>index</parameter></para>
 598     </refsect1>
 599     <refsect1 id="seealso"><title>See Also</title>
 600     <para><citerefentry><refentrytitle>glBindAttribLocation</refentrytitle></citerefentry>,
 601     <citerefentry><refentrytitle>glVertexAttribPointer</refentrytitle></citerefentry></para>
 602     </refsect1>
 603     <refsect1 id="Copyright"><title>Copyright</title>
 604         <para>
 605             Copyright <trademark class="copyright"></trademark> 2003-2005 3Dlabs Inc. Ltd.
 606             This material may be distributed subject to the terms and conditions set forth in
 607             the Open Publication License, v 1.0, 8 June 1999.
 608             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
 609         </para>
 610     </refsect1>
 611 </refentry>