2003-2005
3Dlabs Inc. Ltd.
2010-2013
Khronos Group
glVertexAttribPointer
3G
glVertexAttribPointer
define an array of generic vertex attribute data
C Specification
void glVertexAttribPointer
GLuint index
GLint size
GLenum type
GLboolean normalized
GLsizei stride
const GLvoid * pointer
void glVertexAttribIPointer
GLuint index
GLint size
GLenum type
GLsizei stride
const GLvoid * pointer
void glVertexAttribLPointer
GLuint index
GLint size
GLenum type
GLsizei stride
const GLvoid * pointer
Parameters
index
Specifies the index of the generic vertex
attribute to be modified.
size
Specifies the number of components per
generic vertex attribute. Must
be 1, 2, 3, 4. Additionally, the symbolic constant GL_BGRA
is accepted by glVertexAttribPointer. The initial value is 4.
type
Specifies the data type of each component in
the array. The symbolic constants
GL_BYTE,
GL_UNSIGNED_BYTE,
GL_SHORT,
GL_UNSIGNED_SHORT,
GL_INT, and
GL_UNSIGNED_INT are accepted by glVertexAttribPointer and glVertexAttribIPointer. Additionally
GL_HALF_FLOAT,
GL_FLOAT,
GL_DOUBLE,
GL_FIXED,
GL_INT_2_10_10_10_REV,
GL_UNSIGNED_INT_2_10_10_10_REV and
GL_UNSIGNED_INT_10F_11F_11F_REV are accepted by glVertexAttribPointer.
GL_DOUBLE is also accepted by glVertexAttribLPointer and is
the only token accepted by the type parameter for that function.
The initial value is GL_FLOAT.
normalized
For glVertexAttribPointer, specifies whether fixed-point data values
should be normalized (GL_TRUE)
or converted directly as fixed-point values
(GL_FALSE) when they are
accessed.
stride
Specifies the byte offset between consecutive
generic vertex attributes. If stride
is 0, the generic vertex attributes are
understood to be tightly packed in the
array. The initial value is 0.
pointer
Specifies a offset of the first component of the first generic vertex attribute in the array in the data store of the
buffer currently bound to the GL_ARRAY_BUFFER target. The initial value is 0.
Description
glVertexAttribPointer, glVertexAttribIPointer and glVertexAttribLPointer
specify the
location and data format of the array of generic vertex attributes at index index
to use when rendering. size specifies the number of components per attribute and
must be 1, 2, 3, 4, or GL_BGRA. type specifies the data type
of each component, and stride 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.
For glVertexAttribPointer, if normalized is set to GL_TRUE,
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.
For glVertexAttribIPointer, only the integer types GL_BYTE,
GL_UNSIGNED_BYTE, GL_SHORT, GL_UNSIGNED_SHORT,
GL_INT, GL_UNSIGNED_INT are accepted. Values are always left as integer values.
glVertexAttribLPointer specifies state for a generic vertex attribute array associated
with a shader attribute variable declared with 64-bit double precision components. type
must be GL_DOUBLE. index, size, and
stride behave as described for glVertexAttribPointer and
glVertexAttribIPointer.
If pointer is not NULL
, a non-zero named buffer object must be bound to the
GL_ARRAY_BUFFER target (see glBindBuffer),
otherwise an error is generated. pointer is treated as a byte offset into the buffer object's data store.
The buffer object binding (GL_ARRAY_BUFFER_BINDING) is saved as generic vertex attribute array
state (GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING) for index index.
When a generic vertex attribute array is specified,
size, type,
normalized,
stride, and
pointer are saved as vertex array
state, in addition to the current vertex array buffer object binding.
To enable and disable a generic vertex attribute array, call
glEnableVertexAttribArray and
glDisableVertexAttribArray with index.
If enabled, the generic vertex attribute array is used when glDrawArrays,
glMultiDrawArrays, glDrawElements,
glMultiDrawElements, or glDrawRangeElements
is called.
Notes
Each generic vertex attribute array is initially disabled and isn't accessed when
glDrawElements, glDrawRangeElements,
glDrawArrays, glMultiDrawArrays, or glMultiDrawElements
is called.
GL_UNSIGNED_INT_10F_11F_11F_REV is accepted for type
only if the GL version is 4.4 or higher.
Errors
GL_INVALID_VALUE is generated if
index is greater than or equal to
GL_MAX_VERTEX_ATTRIBS.
GL_INVALID_VALUE is generated if
size is not 1, 2, 3, 4 or (for glVertexAttribPointer),
GL_BGRA.
GL_INVALID_ENUM is generated if
type is not an accepted value.
GL_INVALID_VALUE is generated if
stride is negative.
GL_INVALID_OPERATION is generated if size
is GL_BGRA and type is not GL_UNSIGNED_BYTE,
GL_INT_2_10_10_10_REV or GL_UNSIGNED_INT_2_10_10_10_REV.
GL_INVALID_OPERATION is generated if type
is GL_INT_2_10_10_10_REV or GL_UNSIGNED_INT_2_10_10_10_REV
and size is not 4 or GL_BGRA.
GL_INVALID_OPERATION is generated if type
is GL_UNSIGNED_INT_10F_11F_11F_REV and size
is not 3.
GL_INVALID_OPERATION is generated by glVertexAttribPointer
if size is GL_BGRA and noramlized
is GL_FALSE.
GL_INVALID_OPERATION is generated if zero is bound to the
GL_ARRAY_BUFFER buffer object binding point and the
pointer argument is not NULL.
Associated Gets
glGet
with argument GL_MAX_VERTEX_ATTRIBS
glGetVertexAttrib
with arguments index and GL_VERTEX_ATTRIB_ARRAY_ENABLED
glGetVertexAttrib
with arguments index and GL_VERTEX_ATTRIB_ARRAY_SIZE
glGetVertexAttrib
with arguments index and GL_VERTEX_ATTRIB_ARRAY_TYPE
glGetVertexAttrib
with arguments index and GL_VERTEX_ATTRIB_ARRAY_NORMALIZED
glGetVertexAttrib
with arguments index and GL_VERTEX_ATTRIB_ARRAY_STRIDE
glGetVertexAttrib
with arguments index and GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING
glGet with argument
GL_ARRAY_BUFFER_BINDING
glGetVertexAttribPointerv
with arguments index and
GL_VERTEX_ATTRIB_ARRAY_POINTER
See Also
glBindAttribLocation,
glBindBuffer,
glDisableVertexAttribArray,
glDrawArrays,
glDrawElements,
glDrawRangeElements,
glEnableVertexAttribArray,
glMultiDrawArrays,
glMultiDrawElements,
glVertexAttrib
Copyright
Copyright 2003-2005 3Dlabs Inc. Ltd.
Copyright 2010-2013 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.
http://opencontent.org/openpub/.