Opentk/Source/Bind/Specifications/Docs/ES31/glVertexAttribPointer.xml
2014-03-28 20:06:55 +01:00

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<!DOCTYPE refentry [ <!ENTITY % mathent SYSTEM "math.ent"> %mathent; ]>
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<refentry xmlns="http://docbook.org/ns/docbook" version="5.0" xml:id="glVertexAttribPointer">
<info>
<copyright>
<year>2003-2005</year>
<holder>3Dlabs Inc. Ltd.</holder>
</copyright>
<copyright>
<year>2010-2014</year>
<holder>Khronos Group</holder>
</copyright>
</info>
<refmeta>
<refentrytitle>glVertexAttribPointer</refentrytitle>
<manvolnum>3G</manvolnum>
</refmeta>
<refnamediv>
<refname>glVertexAttribPointer</refname>
<refpurpose>define an array of generic vertex attribute data</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>C Specification</title>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>glVertexAttribPointer</function></funcdef>
<paramdef>GLuint <parameter>index</parameter></paramdef>
<paramdef>GLint <parameter>size</parameter></paramdef>
<paramdef>GLenum <parameter>type</parameter></paramdef>
<paramdef>GLboolean <parameter>normalized</parameter></paramdef>
<paramdef>GLsizei <parameter>stride</parameter></paramdef>
<paramdef>const GLvoid * <parameter>pointer</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>void <function>glVertexAttribIPointer</function></funcdef>
<paramdef>GLuint <parameter>index</parameter></paramdef>
<paramdef>GLint <parameter>size</parameter></paramdef>
<paramdef>GLenum <parameter>type</parameter></paramdef>
<paramdef>GLsizei <parameter>stride</parameter></paramdef>
<paramdef>const GLvoid * <parameter>pointer</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1 xml:id="parameters"><title>Parameters</title>
<variablelist>
<varlistentry>
<term><parameter>index</parameter></term>
<listitem>
<para>Specifies the index of the generic vertex
attribute to be modified.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>size</parameter></term>
<listitem>
<para>Specifies the number of components per
generic vertex attribute. Must
be 1, 2, 3, 4. The initial value is 4.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>type</parameter></term>
<listitem>
<para>Specifies the data type of each component in
the array. The symbolic constants
<constant>GL_BYTE</constant>,
<constant>GL_UNSIGNED_BYTE</constant>,
<constant>GL_SHORT</constant>,
<constant>GL_UNSIGNED_SHORT</constant>,
<constant>GL_INT</constant>, and
<constant>GL_UNSIGNED_INT</constant> are accepted by both functions. Additionally
<constant>GL_HALF_FLOAT</constant>,
<constant>GL_FLOAT</constant>,
<constant>GL_FIXED</constant>,
<constant>GL_INT_2_10_10_10_REV</constant>, and
<constant>GL_UNSIGNED_INT_2_10_10_10_REV</constant> are accepted by <function>glVertexAttribPointer</function>.
The initial value is <constant>GL_FLOAT</constant>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>normalized</parameter></term>
<listitem>
<para>For <function>glVertexAttribPointer</function>, specifies whether fixed-point data values
should be normalized (<constant>GL_TRUE</constant>)
or converted directly as fixed-point values
(<constant>GL_FALSE</constant>) when they are
accessed. This parameter is ignored if <parameter>type</parameter> is <constant>GL_FIXED</constant>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>stride</parameter></term>
<listitem>
<para>
Specifies the byte offset between consecutive generic vertex
attributes. If <parameter>stride</parameter> is 0, the
generic vertex attributes are understood to be tightly
packed in the array. The initial value is 0.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>pointer</parameter></term>
<listitem>
<para>
Specifies a pointer to the first generic vertex attribute in
the array. If a non-zero buffer is currently bound to the
<constant>GL_ARRAY_BUFFER</constant> target,
<parameter>pointer</parameter> specifies an offset of into
the array in the data store of that buffer. The initial
value is 0.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 xml:id="description"><title>Description</title>
<para>
<function>glVertexAttribPointer</function> and <function>glVertexAttribIPointer</function> specify the
location and data format of the array of generic vertex attributes at index <parameter>index</parameter>
to use when rendering. <parameter>size</parameter> specifies the number of components per attribute and
must be 1, 2, 3 or 4. <parameter>type</parameter> specifies the data type
of each component, and <parameter>stride</parameter> specifies the byte stride from one attribute to the next,
allowing vertices and attributes to be packed into a single array or stored in separate arrays.
</para>
<para>
For <function>glVertexAttribPointer</function>, if <parameter>normalized</parameter> is set to <constant>GL_TRUE</constant>,
it indicates that values stored in an integer format are to be mapped to the range [-1,1] (for signed values) or [0,1] (for
unsigned values) when they are accessed and converted to floating point. Otherwise, values will
be converted to floats directly without normalization.
</para>
<para>
For <function>glVertexAttribIPointer</function>, only the integer types <constant>GL_BYTE</constant>,
<constant>GL_UNSIGNED_BYTE</constant>, <constant>GL_SHORT</constant>, <constant>GL_UNSIGNED_SHORT</constant>,
<constant>GL_INT</constant>, <constant>GL_UNSIGNED_INT</constant> are accepted. Values are always left as integer values.
</para>
<para>
If a non-zero named buffer object is bound to the <constant>GL_ARRAY_BUFFER</constant> target
(see <citerefentry><refentrytitle>glBindBuffer</refentrytitle></citerefentry>),
<parameter>pointer</parameter> is treated as a byte offset into the buffer object's data store and
the buffer object binding (<constant>GL_ARRAY_BUFFER_BINDING</constant>) is saved as generic vertex attribute array
state (<constant>GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING</constant>) for index <parameter>index</parameter>.
</para>
<para>
Client vertex arrays (a binding of zero to the <constant>GL_ARRAY_BUFFER</constant> target) are only valid in
conjunction with the zero named vertex array object. This is provided for backwards compatibility with OpenGL ES 2.0.
</para>
<para>
When a generic vertex attribute array is specified,
<parameter>size</parameter>, <parameter>type</parameter>,
<parameter>normalized</parameter>,
<parameter>stride</parameter>, and
<parameter>pointer</parameter> are saved as vertex array
state, in addition to the current vertex array buffer object binding.
</para>
<para>
To enable and disable a generic vertex attribute array, call
<citerefentry><refentrytitle>glEnableVertexAttribArray</refentrytitle></citerefentry> and
<citerefentry><refentrytitle>glDisableVertexAttribArray</refentrytitle></citerefentry> with <parameter>index</parameter>.
If enabled, the generic vertex attribute array is used when <citerefentry><refentrytitle>glDrawArrays</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glDrawArraysInstanced</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glDrawElementsIntanced</refentrytitle></citerefentry>, or <citerefentry><refentrytitle>glDrawRangeElements</refentrytitle></citerefentry>
is called.
</para>
</refsect1>
<refsect1 xml:id="notes"><title>Notes</title>
<para>
Each generic vertex attribute array is initially disabled and isn't accessed when
<citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glDrawRangeElements</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glDrawArrays</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glDrawArraysInstanced</refentrytitle></citerefentry>, or <citerefentry><refentrytitle>glDrawElementsInstanced</refentrytitle></citerefentry>
is called.
</para>
</refsect1>
<refsect1 xml:id="errors"><title>Errors</title>
<para>
<constant>GL_INVALID_VALUE</constant> is generated if
<parameter>index</parameter> is greater than or equal to
<constant>GL_MAX_VERTEX_ATTRIBS</constant>.
</para>
<para>
<constant>GL_INVALID_VALUE</constant> is generated if
<parameter>size</parameter> is not 1, 2, 3 or 4.
</para>
<para>
<constant>GL_INVALID_ENUM</constant> is generated if
<parameter>type</parameter> is not an accepted value.
</para>
<para>
<constant>GL_INVALID_VALUE</constant> is generated if
<parameter>stride</parameter> is negative.
</para>
<para>
<constant>GL_INVALID_OPERATION</constant> is generated if
<parameter>type</parameter> is
<constant>GL_INT_2_10_10_10_REV</constant> or
<constant>GL_UNSIGNED_INT_2_10_10_10_REV</constant> and
<parameter>size</parameter> is not 4.
</para>
<para>
<constant>GL_INVALID_OPERATION</constant> is generated a
non-zero vertex array object is bound, zero is bound to the
<constant>GL_ARRAY_BUFFER</constant> buffer object binding point
and the <parameter>pointer</parameter> argument is not
<constant>NULL</constant>.
</para>
</refsect1>
<refsect1 xml:id="associatedgets"><title>Associated Gets</title>
<para><citerefentry><refentrytitle>glGet</refentrytitle></citerefentry>
with argument <constant>GL_MAX_VERTEX_ATTRIBS</constant></para>
<para><citerefentry><refentrytitle>glGetVertexAttrib</refentrytitle></citerefentry>
with arguments <parameter>index</parameter> and <constant>GL_VERTEX_ATTRIB_ARRAY_ENABLED</constant></para>
<para><citerefentry><refentrytitle>glGetVertexAttrib</refentrytitle></citerefentry>
with arguments <parameter>index</parameter> and <constant>GL_VERTEX_ATTRIB_ARRAY_SIZE</constant></para>
<para><citerefentry><refentrytitle>glGetVertexAttrib</refentrytitle></citerefentry>
with arguments <parameter>index</parameter> and <constant>GL_VERTEX_ATTRIB_ARRAY_TYPE</constant></para>
<para><citerefentry><refentrytitle>glGetVertexAttrib</refentrytitle></citerefentry>
with arguments <parameter>index</parameter> and <constant>GL_VERTEX_ATTRIB_ARRAY_NORMALIZED</constant></para>
<para><citerefentry><refentrytitle>glGetVertexAttrib</refentrytitle></citerefentry>
with arguments <parameter>index</parameter> and <constant>GL_VERTEX_ATTRIB_ARRAY_STRIDE</constant></para>
<para><citerefentry><refentrytitle>glGetVertexAttrib</refentrytitle></citerefentry>
with arguments <parameter>index</parameter> and <constant>GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING</constant></para>
<para><citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument
<constant>GL_ARRAY_BUFFER_BINDING</constant></para>
<para><citerefentry><refentrytitle>glGetVertexAttribPointerv</refentrytitle></citerefentry>
with arguments <parameter>index</parameter> and
<constant>GL_VERTEX_ATTRIB_ARRAY_POINTER</constant></para>
</refsect1>
<refsect1 xml:id="versions">
<title>API Version Support</title>
<informaltable>
<tgroup cols="4" align="left">
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="apifunchead.xml" xpointer="xpointer(/*/*)"/>
<tbody>
<row>
<entry><function>glVertexAttribPointer</function></entry>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="apiversion.xml" xpointer="xpointer(/*/*[@role='es20']/*)"/>
</row>
<row>
<entry><function>glVertexAttribIPointer</function></entry>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="apiversion.xml" xpointer="xpointer(/*/*[@role='es30']/*)"/>
</row>
</tbody>
</tgroup>
</informaltable>
</refsect1>
<refsect1 xml:id="seealso"><title>See Also</title>
<para>
<citerefentry><refentrytitle>glBindAttribLocation</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glBindBuffer</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glDisableVertexAttribArray</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glDrawArrays</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glDrawRangeElements</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glEnableVertexAttribArray</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glDrawArraysInstanced</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glDrawElementsIntanced</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glVertexAttrib</refentrytitle></citerefentry>
</para>
</refsect1>
<refsect1 xml:id="Copyright"><title>Copyright</title>
<para>
Copyright <trademark class="copyright"/> 2003-2005 3Dlabs Inc. Ltd.
Copyright <trademark class="copyright"/> 2010-2014 Khronos Group.
This material may be distributed subject to the terms and conditions set forth in
the Open Publication License, v 1.0, 8 June 1999.
<link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://opencontent.org/openpub/">http://opencontent.org/openpub/</link>.
</para>
</refsect1>
</refentry>