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`, and `GL_UNSIGNED_INT_2_10_10_10_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.

## 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 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. 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/.