GLGETBUFFERSUBDATA(3G)

NAME
glGetBufferSubData, glGetNamedBufferSubData - returns a subset of a buffer object's data store

C SPECIFICATION

void glGetBufferSubData(GLenum target, GLintptr offset, GLsizeiptr size, GLvoid * data);

void glGetNamedBufferSubData(GLuint buffer, GLintptr offset, GLsizei size, void *data);

PARAMETERS

target
    Specifies the target to which the buffer object is bound for glGetBufferSubData, which must be one of the buffer binding targets in the following table:
    Buffer Binding Target | Purpose
    GL_ARRAY_BUFFER | Vertex attributes
    GL_ATOMIC_COUNTER_BUFFER | Atomic counter storage
    GL_COPY_READ_BUFFER | Buffer copy source
    GL_COPY_WRITE_BUFFER | Buffer copy destination
    GL_DISPATCH_INDIRECT_BUFFER | Indirect compute dispatch commands
    GL_DRAW_INDIRECT_BUFFER | Indirect command arguments
    GL_ELEMENT_ARRAY_BUFFER | Vertex array indices
    GL_PIXEL_PACK_BUFFER | Pixel read target
    GL_PIXEL_UNPACK_BUFFER | Texture data source
    GL_QUERY_BUFFER | Query result buffer
    GL_SHADER_STORAGE_BUFFER | Read-write storage for shaders
    GL_TEXTURE_BUFFER | Texture data buffer
    GL_TRANSFORM_FEEDBACK_BUFFER | Transform feedback buffer
    GL_UNIFORM_BUFFER | Uniform block storage

buffer
    Specifies the name of the buffer object for glGetNamedBufferSubData.

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 and glGetNamedBufferSubData return some or all of the data contents of the data store of the specified buffer object. Data starting at byte offset offset and extending for size bytes is copied from the buffer object's 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_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 by glGetBufferSubData if target is not one of the generic buffer binding targets.

GL_INVALID_OPERATION is generated by glGetBufferSubData if zero is bound to target.

GL_INVALID_OPERATION is generated by glGetNamedBufferSubData if buffer is not the name of an existing buffer object.

GL_INVALID_VALUE is generated if offset or size is negative, or if $offset + size$ is greater than the value of GL_BUFFER_SIZE for the buffer object.

GL_INVALID_OPERATION is generated if the buffer object is mapped with glMapBufferRange() or glMapBuffer(), unless it was mapped with the GL_MAP_PERSISTENT_BIT bit set in the glMapBufferRange access flags.

VERSION SUPPORT
 | OpenGL Version
Function / Feature Name | 2.0 | 2.1 | 3.0 | 3.1 | 3.2 | 3.3 | 4.0 | 4.1 | 4.2 | 4.3 | 4.4 | 4.5
glGetBufferSubData | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔
glGetNamedBufferSubData | - | - | - | - | - | - | - | - | - | - | - | ✔

SEE ALSO

glBindBuffer(), glBufferData(), glBufferSubData(), glMapBuffer(), glUnmapBuffer()

COPYRIGHT

Copyright © 2005 Addison-Wesley. Copyright © 2011-2014 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/.

COPYRIGHT
Copyright © 2005 Sams Publishing
Copyright © 2011-2014 Khronos Group