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glBindBuffer — bind a named buffer object
void glBindBuffer( | GLenum | target, |
| GLuint | buffer); |
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.
bufferSpecifies the name of a buffer object.
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
READ_WRITE access and 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 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_ARRAY_ELEMENT_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.
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.
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.
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
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/.