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_COPY_READ_BUFFER
,
GL_COPY_WRITE_BUFFER
,
GL_ELEMENT_ARRAY_BUFFER
,
GL_PIXEL_PACK_BUFFER
,
GL_PIXEL_UNPACK_BUFFER
,
GL_TEXTURE_BUFFER
,
GL_TRANSFORM_FEEDBACK_BUFFER
, or
GL_UNIFORM_BUFFER
.
buffer
Specifies the name of a buffer object.
glBindBuffer
binds a buffer object to the specified buffer binding point. Calling glBindBuffer
with
target
set to one of the accepted symbolic constants and buffer
set to the name
of a buffer object binds that buffer object name to the target. If no buffer object with name buffer
exists, one is created with that name. 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 (if supported for that target).
Buffer object names and the corresponding buffer object contents are local to
the shared object space of the current
GL rendering context;
two rendering contexts share buffer object names only if they
explicitly enable sharing between contexts through the appropriate GL windows interfaces functions.
glGenBuffers must be used to generate a set of unused 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 a non-zero buffer object is bound to the GL_ARRAY_BUFFER
target,
the vertex array pointer parameter is 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,
glDrawElementsInstanced,
glDrawElementsBaseVertex,
glDrawRangeElements,
glDrawRangeElementsBaseVertex,
glMultiDrawElements, or
glMultiDrawElementsBaseVertex is 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,
glGetTexImage, and
glReadPixels. The pointer parameter is
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:
glCompressedTexImage1D,
glCompressedTexImage2D,
glCompressedTexImage3D,
glCompressedTexSubImage1D,
glCompressedTexSubImage2D,
glCompressedTexSubImage3D,
glTexImage1D,
glTexImage2D,
glTexImage3D,
glTexSubImage1D,
glTexSubImage2D, and
glTexSubImage3D. The pointer parameter is
interpreted as an offset within the buffer object measured in basic machine units.
The buffer targets GL_COPY_READ_BUFFER
and GL_COPY_WRITE_BUFFER
are provided to allow glCopyBufferSubData
to be used without disturbing the state of other bindings. However, glCopyBufferSubData
may be used with any pair of buffer binding points.
The GL_TRANSFORM_FEEDBACK_BUFFER
buffer binding point may be passed to glBindBuffer
,
but will not directly affect transform feedback state. Instead, the indexed GL_TRANSFORM_FEEDBACK_BUFFER
bindings must be used through a call to glBindBufferBase
or glBindBufferRange. This will affect the generic
GL_TRANSFORM_FEEDBACK_BUFFER
binding.
Likewise, the GL_UNIFORM_BUFFER
buffer binding point may be used, but does not directly affect
uniform buffer state. glBindBufferBase
or glBindBufferRange must be used to bind a buffer to
an indexed uniform buffer binding point.
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.
The GL_COPY_READ_BUFFER
, GL_UNIFORM_BUFFER
and
GL_TEXTURE_BUFFER
targets are available only if the GL version is 3.1 or greater.
GL_INVALID_ENUM
is generated if target
is not one of the allowable
values.
GL_INVALID_VALUE
is generated if buffer
is not a name previously returned
from a call to glGenBuffers.
glGet with argument GL_ARRAY_BUFFER_BINDING
glGet with argument GL_COPY_READ_BUFFER_BINDING
glGet with argument GL_COPY_WRITE_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
glGet with argument GL_TRANSFORM_FEEDBACK_BUFFER_BINDING
glGet with argument GL_UNIFORM_BUFFER_BINDING
glGenBuffers, glBindBufferBase, glBindBufferRange, glMapBuffer, glUnmapBuffer, glDeleteBuffers, glGet, glIsBuffer
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/.