GLAPI/glGetBufferSubData

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glGetBufferSubData
Core in version 4.4
Core since version 1.5

glGetBufferSubData: returns a subset of a buffer object's data store

Function Definition

 void glGetBufferSubData(GLenum target​, GLintptr offset​, GLsizeiptr size​, GLvoid * data​);
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 from which data will be returned, measured in bytes.
size
Specifies the size in bytes of the data store region being returned.
data
Specifies a pointer to the location where buffer object data is returned.

Description

glGetBufferSubData returns some or all of the data from the buffer object currently bound to target​. Data starting at byte offset offset​ and extending for size​ bytes is copied from the data store to the memory pointed to by data​. An error is thrown if the buffer object is currently mapped, or if offset​ and size​ together define a range beyond the bounds of the buffer object's data store.

Notes

If an error is generated, no change is made to the contents of data​.

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

The GL_DISPATCH_INDIRECT_BUFFER​ target is available only if the GL version is 4.3 or greater.

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

Errors

GL_INVALID_ENUM​ is generated if target​ is not GL_ARRAY_BUFFER​, GL_ELEMENT_ARRAY_BUFFER​, GL_PIXEL_PACK_BUFFER​, or GL_PIXEL_UNPACK_BUFFER​.

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 queried is mapped.

See Also

glBindBuffer, glBufferData, glBufferSubData, glMapBufferRange, glUnmapBuffer

Copyright

Copyright © 2005 Addison-Wesley. Copyright © 2011-2013 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/.