2005
Sams Publishing
glBindBuffer
3G

# glBindBuffer

bind a named buffer object

## C Specification

                    void glBindBuffer
                    GLenum target
                    GLuint buffer

## Parameters

`target`

  Specifies the target to which the buffer object is bound. The symbolic constant must be `GL_ARRAY_BUFFER`, `GL_ELEMENT_ARRAY_BUFFER`, `GL_PIXEL_PACK_BUFFER`, or `GL_PIXEL_UNPACK_BUFFER`.

`buffer`

  Specifies the name of a buffer object.

## Description

`glBindBuffer` lets you create or use a named buffer object. Calling `glBindBuffer` with `target` set to `GL_ARRAY_BUFFER`, `GL_ELEMENT_ARRAY_BUFFER`, `GL_PIXEL_PACK_BUFFER` or `GL_PIXEL_UNPACK_BUFFER` and `buffer` set to the name of the new buffer object binds the buffer object name to the target. When a buffer object is bound to a target, the previous binding for that target is automatically broken.

Buffer object names are unsigned integers. The value zero is reserved, but there is no default buffer object for each buffer object target. Instead, `buffer` set to zero effectively unbinds any buffer object previously bound, and restores client memory usage for that buffer object target. Buffer object names and the corresponding buffer object contents are local to the shared display-list space (see glXCreateContext) of the current GL rendering context; two rendering contexts share buffer object names only if they also share display lists.

You may use glGenBuffers to generate a set of new buffer object names.

The state of a buffer object immediately after it is first bound is an unmapped zero-sized memory buffer with `GL_READ_WRITE` access and `GL_STATIC_DRAW` usage.

While a non-zero buffer object name is bound, GL operations on the target to which it is bound affect the bound buffer object, and queries of the target to which it is bound return state from the bound buffer object. While buffer object name zero is bound, as in the initial state, attempts to modify or query state on the target to which it is bound generates an `GL_INVALID_OPERATION` error.

When vertex array pointer state is changed, for example by a call to glNormalPointer, the current buffer object binding (`GL_ARRAY_BUFFER_BINDING`) is copied into the corresponding client state for the vertex array type being changed, for example `GL_NORMAL_ARRAY_BUFFER_BINDING`. While a non-zero buffer object is bound to the `GL_ARRAY_BUFFER` target, the vertex array pointer parameter that is traditionally interpreted as a pointer to client-side memory is instead interpreted as an offset within the buffer object measured in basic machine units.

While a non-zero buffer object is bound to the `GL_ELEMENT_ARRAY_BUFFER` target, the indices parameter of glDrawElements, glDrawRangeElements, or glMultiDrawElements that is traditionally interpreted as a pointer to client-side memory is instead interpreted as an offset within the buffer object measured in basic machine units.

While a non-zero buffer object is bound to the `GL_PIXEL_PACK_BUFFER` target, the following commands are affected: glGetCompressedTexImage, glGetConvolutionFilter, glGetHistogram, glGetMinmax, glGetPixelMap, glGetPolygonStipple, glGetSeparableFilter, glGetTexImage, and glReadPixels. The pointer parameter that is traditionally interpreted as a pointer to client-side memory where the pixels are to be packed is instead interpreted as an offset within the buffer object measured in basic machine units.

While a non-zero buffer object is bound to the `GL_PIXEL_UNPACK_BUFFER` target, the following commands are affected: glBitmap, glColorSubTable, glColorTable, glCompressedTexImage1D, glCompressedTexImage2D, glCompressedTexImage3D, glCompressedTexSubImage1D, glCompressedTexSubImage2D, glCompressedTexSubImage3D, glConvolutionFilter1D, glConvolutionFilter2D, glDrawPixels, glPixelMap, glPolygonStipple, glSeparableFilter2D, glTexImage1D, glTexImage2D, glTexImage3D, glTexSubImage1D, glTexSubImage2D, and glTexSubImage3D. The pointer parameter that is traditionally interpreted as a pointer to client-side memory from which the pixels are to be unpacked is instead interpreted as an offset within the buffer object measured in basic machine units.

A buffer object binding created with `glBindBuffer` remains active until a different buffer object name is bound to the same target, or until the bound buffer object is deleted with glDeleteBuffers.

Once created, a named buffer object may be re-bound to any target as often as needed. However, the GL implementation may make choices about how to optimize the storage of a buffer object based on its initial binding target.

## Notes

`glBindBuffer` is available only if the GL version is 1.5 or greater.

`GL_PIXEL_PACK_BUFFER` and `GL_PIXEL_UNPACK_BUFFER` are available only if the GL version is 2.1 or greater.

## Errors

`GL_INVALID_ENUM` is generated if `target` is not one of the allowable values.

`GL_INVALID_OPERATION` is generated if `glBindBuffer` is executed between the execution of glBegin and the corresponding execution of glEnd.

## Associated Gets

glGet with argument `GL_ARRAY_BUFFER_BINDING`

glGet with argument `GL_ELEMENT_ARRAY_BUFFER_BINDING`

glGet with argument `GL_PIXEL_PACK_BUFFER_BINDING`

glGet with argument `GL_PIXEL_UNPACK_BUFFER_BINDING`

## See Also

glDeleteBuffers, glGenBuffers, glGet, glIsBuffer

## Copyright

Copyright 2005 Addison-Wesley. 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/.