2005
Sams Publishing
glBufferSubData
3G
glBufferSubData
updates a subset of a buffer object's data store
C Specification
void glBufferSubData
GLenum target
GLintptr offset
GLsizeiptr size
const GLvoid * data
Parameters
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.
offset
Specifies the offset into the buffer object's data store where data replacement will begin,
measured in bytes.
size
Specifies the size in bytes of the data store region being replaced.
data
Specifies a pointer to the new data that will be copied into the data store.
Description
glBufferSubData redefines some or all of the data store for the buffer object currently
bound to target. Data starting at byte offset offset and
extending for size bytes is copied to the data store from the memory pointed to by
data. An error is thrown if offset and size
together define a range beyond the bounds of the buffer object's data store.
Notes
When replacing the entire data store, consider using glBufferSubData rather
than completely recreating the data store with glBufferData. This avoids the cost of
reallocating the data store.
Consider using multiple buffer objects to avoid stalling the rendering pipeline during data store updates.
If any rendering in the pipeline makes reference to data in the buffer object being updated by
glBufferSubData, especially from the specific region being updated, that rendering must
drain from the pipeline before the data store can be updated.
Clients must align data elements consistent with the requirements of the client
platform, with an additional base-level requirement that an offset within a buffer to
a datum comprising N bytes be a
multiple of N.
The GL_ATOMIC_COUNTER_BUFFER 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 accepted buffer targets.
GL_INVALID_VALUE is generated if offset or
size is negative, or if together they define a region of memory
that extends beyond the buffer object's allocated data store.
GL_INVALID_OPERATION is generated if the reserved buffer object name 0 is bound to target.
GL_INVALID_OPERATION is generated if the buffer object being updated is mapped.
Associated Gets
glGetBufferSubData
See Also
glBindBuffer,
glBufferData,
glMapBuffer,
glUnmapBuffer
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/.