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/.