'\" t
.\"     Title: glGetBufferSubData
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.78.1 <http://docbook.sf.net/>
.\"      Date: 05/21/2015
.\"    Manual: [FIXME: manual]
.\"    Source: [FIXME: source]
.\"  Language: English
.\"
.TH "GLGETBUFFERSUBDATA" "3G" "05/21/2015" "[FIXME: source]" "[FIXME: manual]"
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.SH "NAME"
glGetBufferSubData, glGetNamedBufferSubData \- returns a subset of a buffer object\*(Aqs data store
.SH "C SPECIFICATION"
.HP \w'void\ glGetBufferSubData('u
.BI "void glGetBufferSubData(GLenum\ " "target" ", GLintptr\ " "offset" ", GLsizeiptr\ " "size" ", GLvoid\ *\ " "data" ");"
.HP \w'void\ glGetNamedBufferSubData('u
.BI "void glGetNamedBufferSubData(GLuint\ " "buffer" ", GLintptr\ " "offset" ", GLsizei\ " "size" ", void\ *" "data" ");"
.SH "PARAMETERS"
.PP
\fItarget\fR
.RS 4
Specifies the target to which the buffer object is bound for
\fBglGetBufferSubData\fR, which must be one of the buffer binding targets in the following table:
.TS
allbox tab(:);
lB lB.
T{
\fBBuffer Binding Target\fR
T}:T{
\fBPurpose\fR
T}
.T&
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l.
T{
\fBGL_ARRAY_BUFFER\fR
T}:T{
Vertex attributes
T}
T{
\fBGL_ATOMIC_COUNTER_BUFFER\fR
T}:T{
Atomic counter storage
T}
T{
\fBGL_COPY_READ_BUFFER\fR
T}:T{
Buffer copy source
T}
T{
\fBGL_COPY_WRITE_BUFFER\fR
T}:T{
Buffer copy destination
T}
T{
\fBGL_DISPATCH_INDIRECT_BUFFER\fR
T}:T{
Indirect compute dispatch commands
T}
T{
\fBGL_DRAW_INDIRECT_BUFFER\fR
T}:T{
Indirect command arguments
T}
T{
\fBGL_ELEMENT_ARRAY_BUFFER\fR
T}:T{
Vertex array indices
T}
T{
\fBGL_PIXEL_PACK_BUFFER\fR
T}:T{
Pixel read target
T}
T{
\fBGL_PIXEL_UNPACK_BUFFER\fR
T}:T{
Texture data source
T}
T{
\fBGL_QUERY_BUFFER\fR
T}:T{
Query result buffer
T}
T{
\fBGL_SHADER_STORAGE_BUFFER\fR
T}:T{
Read\-write storage for shaders
T}
T{
\fBGL_TEXTURE_BUFFER\fR
T}:T{
Texture data buffer
T}
T{
\fBGL_TRANSFORM_FEEDBACK_BUFFER\fR
T}:T{
Transform feedback buffer
T}
T{
\fBGL_UNIFORM_BUFFER\fR
T}:T{
Uniform block storage
T}
.TE
.sp
.RE
.PP
\fIbuffer\fR
.RS 4
Specifies the name of the buffer object for
\fBglGetNamedBufferSubData\fR\&.
.RE
.PP
\fIoffset\fR
.RS 4
Specifies the offset into the buffer object\*(Aqs data store from which data will be returned, measured in bytes\&.
.RE
.PP
\fIsize\fR
.RS 4
Specifies the size in bytes of the data store region being returned\&.
.RE
.PP
\fIdata\fR
.RS 4
Specifies a pointer to the location where buffer object data is returned\&.
.RE
.SH "DESCRIPTION"
.PP
\fBglGetBufferSubData\fR
and
\fBglGetNamedBufferSubData\fR
return some or all of the data contents of the data store of the specified buffer object\&. Data starting at byte offset
\fIoffset\fR
and extending for
\fIsize\fR
bytes is copied from the buffer object\*(Aqs data store to the memory pointed to by
\fIdata\fR\&. An error is thrown if the buffer object is currently mapped, or if
\fIoffset\fR
and
\fIsize\fR
together define a range beyond the bounds of the buffer object\*(Aqs data store\&.
.SH "NOTES"
.PP
If an error is generated, no change is made to the contents of
\fIdata\fR\&.
.PP
The
\fBGL_ATOMIC_COUNTER_BUFFER\fR
target is available only if the GL version is 4\&.2 or greater\&.
.PP
The
\fBGL_DISPATCH_INDIRECT_BUFFER\fR
and
\fBGL_SHADER_STORAGE_BUFFER\fR
targets are available only if the GL version is 4\&.3 or greater\&.
.PP
The
\fBGL_QUERY_BUFFER\fR
target is available only if the GL version is 4\&.4 or greater\&.
.SH "ERRORS"
.PP
\fBGL_INVALID_ENUM\fR
is generated by
\fBglGetBufferSubData\fR
if
\fItarget\fR
is not one of the generic buffer binding targets\&.
.PP
\fBGL_INVALID_OPERATION\fR
is generated by
\fBglGetBufferSubData\fR
if zero is bound to
\fItarget\fR\&.
.PP
\fBGL_INVALID_OPERATION\fR
is generated by
\fBglGetNamedBufferSubData\fR
if
\fIbuffer\fR
is not the name of an existing buffer object\&.
.PP
\fBGL_INVALID_VALUE\fR
is generated if
\fIoffset\fR
or
\fIsize\fR
is negative, or if $offset + size$ is greater than the value of
\fBGL_BUFFER_SIZE\fR
for the buffer object\&.
.PP
\fBGL_INVALID_OPERATION\fR
is generated if the buffer object is mapped with
\fBglMapBufferRange\fR()
or
\fBglMapBuffer\fR(), unless it was mapped with the
\fBGL_MAP_PERSISTENT_BIT\fR
bit set in the
\fBglMapBufferRange\fR\fIaccess\fR
flags\&.
.SH "VERSION SUPPORT"
.TS
allbox tab(:);
lB cB s s s s s s s s s s s
lB cB cB cB cB cB cB cB cB cB cB cB cB.
T{

T}:T{
\fBOpenGL Version\fR
T}
T{
\fBFunction / Feature Name\fR
T}:T{
\fB2\&.0\fR
T}:T{
\fB2\&.1\fR
T}:T{
\fB3\&.0\fR
T}:T{
\fB3\&.1\fR
T}:T{
\fB3\&.2\fR
T}:T{
\fB3\&.3\fR
T}:T{
\fB4\&.0\fR
T}:T{
\fB4\&.1\fR
T}:T{
\fB4\&.2\fR
T}:T{
\fB4\&.3\fR
T}:T{
\fB4\&.4\fR
T}:T{
\fB4\&.5\fR
T}
.T&
l c c c c c c c c c c c c
l c c c c c c c c c c c c.
T{
\fBglGetBufferSubData\fR
T}:T{
✔
T}:T{
✔
T}:T{
✔
T}:T{
✔
T}:T{
✔
T}:T{
✔
T}:T{
✔
T}:T{
✔
T}:T{
✔
T}:T{
✔
T}:T{
✔
T}:T{
✔
T}
T{
\fBglGetNamedBufferSubData\fR
T}:T{
\-
T}:T{
\-
T}:T{
\-
T}:T{
\-
T}:T{
\-
T}:T{
\-
T}:T{
\-
T}:T{
\-
T}:T{
\-
T}:T{
\-
T}:T{
\-
T}:T{
✔
T}
.TE
.sp
.SH "SEE ALSO"
.PP
\fBglBindBuffer\fR(),
\fBglBufferData\fR(),
\fBglBufferSubData\fR(),
\fBglMapBuffer\fR(),
\fBglUnmapBuffer\fR()
.SH "COPYRIGHT"
.PP
Copyright
\(co
2005 Addison\-Wesley\&. Copyright
\(co
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\&.
\m[blue]\fBhttp://opencontent\&.org/openpub/\fR\m[]\&.
.SH "COPYRIGHT"
.br
Copyright \(co 2005 Sams Publishing
.br
Copyright \(co 2011-2014 Khronos Group
.br