creates and initializes a buffer object's data store
Signature
glBufferData(
GLenum (
target
)
,
GLsizeiptr (
size
)
,
const GLvoid * (
data
)
,
GLenum (
usage
)
)-> void
glBufferData(
target
,
size
,
data
,
usage
)
Copy given data into the currently bound vertex-buffer-data object
target -- the symbolic constant indicating which buffer type is intended
size -- if provided, the count-in-bytes of the array
data -- data-pointer to be used, may be None to initialize without
copying over a data-set
usage -- hint to the driver as to how to set up access to the buffer
Note: parameter "size" can be omitted, which makes the signature
glBufferData( target, data, usage )
instead of:
glBufferData( target, size, data, usage )
Parameters
Description
glBufferData
creates a new data store for the buffer object currently bound to
target
. Any pre-existing data store is deleted. The new data store is created with the
specified
size
in bytes and
usage
. If
data
is not
NULL
, the data store is initialized with data from this pointer. In its initial
state, the new data store is not mapped, it has a
NULL
mapped pointer, and its mapped access
is
GL_READ_WRITE
.
usage
is a hint to the GL implementation as to how a buffer object's data store will be
accessed. This enables the GL implementation to make more intelligent decisions that may significantly
impact buffer object performance. It does not, however, constrain the actual usage of the data store.
usage
can be broken down into two parts: first, the frequency of access (modification
and usage), and second, the nature of that access. The frequency of access may be one of these:
- STREAM
-
The data store contents will be modified once and used at most a few times.
- STATIC
-
The data store contents will be modified once and used many times.
- DYNAMIC
-
The data store contents will be modified repeatedly and used many times.
The nature of access may be one of these:
- DRAW
-
The data store contents are modified by the application, and used as the source for GL drawing and image specification commands.
- READ
-
The data store contents are modified by reading data from the GL, and used to return that data when queried by the application.
- COPY
-
The data store contents are modified by reading data from the GL, and used as the source for GL drawing and image specification commands.
Notes
If
data
is
NULL
, a data store of the specified size is still created,
but its contents remain uninitialized and thus undefined.
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
.
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.
Errors
GL_INVALID_ENUM
is generated if
target
is not
one of the accepted buffer targets.
GL_INVALID_ENUM
is generated if
usage
is not
GL_STREAM_DRAW
,
GL_STREAM_READ
,
GL_STREAM_COPY
,
GL_STATIC_DRAW
,
GL_STATIC_READ
,
GL_STATIC_COPY
,
GL_DYNAMIC_DRAW
,
GL_DYNAMIC_READ
, or
GL_DYNAMIC_COPY
.
GL_INVALID_VALUE
is generated if
size
is negative.
GL_INVALID_OPERATION
is generated if the reserved buffer object name 0 is bound to
target
.
GL_OUT_OF_MEMORY
is generated if the GL is unable to create a data store with the specified
size
.
Associated Gets
See Also
Copyright
Copyright
2005 Addison-Wesley.
Copyright
2011-2012 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/
.
Sample Code References
The following code samples have been found which appear to reference the functions described here. Take care that the code may be old, broken or not even use PyOpenGL.
glBufferData
