GLAPI/glBindBuffer

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glBindBuffer
Core in version 4.4
Core since version 1.5

glBindBuffer: bind a named buffer object

Function Definition

 void glBindBuffer(GLenum target​, GLuint buffer​);
target
Specifies the target buffer object. The symbolic constant must be GL_ARRAY_BUFFER​, GL_ATOMIC_COUNTER_BUFFER​, GL_COPY_READ_BUFFER​, GL_COPY_WRITE_BUFFER​, GL_DRAW_INDIRECT_BUFFER​, GL_DISPATCH_INDIRECT_BUFFER​, GL_ELEMENT_ARRAY_BUFFER​, GL_PIXEL_PACK_BUFFER​, GL_PIXEL_UNPACK_BUFFER​, GL_QUERY_BUFFER​, GL_SHADER_STORAGE_BUFFER​, GL_TEXTURE_BUFFER​, GL_TRANSFORM_FEEDBACK_BUFFER​, or GL_UNIFORM_BUFFER​.
buffer
Specifies the name of a buffer object.

Description

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.

When a non-zero buffer object is bound to the GL_DRAW_INDIRECT_BUFFER​ target, parameters for draws issued through glDrawArraysIndirect and glDrawElementsIndirect are sourced from the specified offset in that buffer object's data store.

When a non-zero buffer object is bound to the GL_DISPATCH_INDIRECT_BUFFER​ target, the parameters for compute dispatches issued through glDispatchComputeIndirect are sourced from the specified offset in that buffer object's data store.

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​, GL_ATOMIC_COUNTER_BUFFER​ and GL_SHADER_STORAGE_BUFFER​ buffer binding points may be used, but do not directly affect uniform buffer, atomic counter buffer or shader storage buffer state, respectively. glBindBufferBase or glBindBufferRange must be used to bind a buffer to an indexed uniform buffer, atomic counter buffer or shader storage buffer binding point.

The GL_QUERY_BUFFER​ binding point is used to specify a buffer object that is to receive the results of query objects through calls to the glGetQueryObject family of commands.

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

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.

The GL_ATOMIC_COUNTER_BUFER​ target is available only if the GL version is 4.2 or greater.

The GL_DISPATCH_INDIRECT_BUFFER​ and GL_SHADER_STORAGE_BUFFER​ targets are available only if the GL version is 4.3 or greater.

The GL_QUERY_BUFFER​ target is available only if the GL version is 4.4 or greater.

Errors

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.

Associated Gets

glGet with argument GL_ARRAY_BUFFER_BINDING​

glGet with argument GL_ATOMIC_COUNTER_BUFFER_BINDING​

glGet with argument GL_COPY_READ_BUFFER_BINDING​

glGet with argument GL_COPY_WRITE_BUFFER_BINDING​

glGet with argument GL_DRAW_INDIRECT_BUFFER_BINDING​

glGet with argument GL_DISPATCH_INDIRECT_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_SHADER_STORAGE_BUFFER_BINDING​

glGet with argument GL_TRANSFORM_FEEDBACK_BUFFER_BINDING​

glGet with argument GL_UNIFORM_BUFFER_BINDING​

See Also

glGenBuffers, glDeleteBuffers, glIsBuffer, glBindBufferRange, glMapBufferRange, glUnmapBuffer

Copyright

Copyright © 2005 Addison-Wesley. 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/.