GLAPI/glBufferStorage

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glBufferStorage
Core in version 4.4
Core since version 4.4
Core ARB extension ARB_buffer_storage

glBufferStorage: creates and initializes a buffer object's immutable data store

Function Definition

 void glBufferStorage(GLenum target​, GLsizeiptr size​, const GLvoid * data​, GLbitfield flags​);
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​.
size
Specifies the size in bytes of the buffer object's new data store.
data
Specifies a pointer to data that will be copied into the data store for initialization, or NULL​ if no data is to be copied.
flags
Specifies the intended usage of the buffer's data store. Must be a bitwise combination of the following flags. GL_DYNAMIC_STORAGE_BIT​, GL_MAP_READ_BIT​GL_MAP_WRITE_BIT​, GL_MAP_PERSISTENT_BIT​, GL_MAP_COHERENT_BIT​, and GL_CLIENT_STORAGE_BIT​.

Description

glBufferStorage creates a new immutable data store for the buffer object currently bound to target​. The size of the data store is specified by size​. If an initial data is available, its address may be supplied in data​. Otherwise, to create an uninitialized data store, data​ should be NULL​.

The flags​ parameters specifies the intended usage of the buffer's data store. It must be a bitwise combination of a subset of the following flags:

GL_DYNAMIC_STORAGE_BIT​
The contents of the data store may be updated after creation through calls to glBufferSubData. If this bit is not set, the buffer content may not be directly updated by the client. The data argument may be used to specify the initial content of the buffer's data store regardless of the presence of the GL_DYNAMIC_STORAGE_BIT​. Regardless of the presence of this bit, buffers may always be updated with server-side calls such as glCopyBufferSubData and glClearBufferSubData.
GL_MAP_READ_BIT​
The data store may be mapped by the client for read access and a pointer in the client's address space obtained that may be read from.
GL_MAP_WRITE_BIT​
The data store may be mapped by the client for write access and a pointer in the client's address space obtained that may be written through.
GL_MAP_PERSISTENT_BIT​
The client may request that the server read from or write to the buffer while it is mapped. The client's pointer to the data store remains valid so long as the data store is mapped, even during execution of drawing or dispatch commands.
GL_MAP_COHERENT_BIT​
Shared access to buffers that are simultaneously mapped for client access and are used by the server will be coherent, so long as that mapping is performed using glMapBufferRange. That is, data written to the store by either the client or server will be immediately visible to the other with no further action taken by the application. In particular,
GL_CLIENT_STORAGE_BIT​
A hint that the buffer object's data should be stored in client memory. Assuming that such a distinction exists in the driver.

The allowed combinations of flags are subject to certain restrictions. They are as follows:

  • If flags​ contains GL_MAP_PERSISTENT_BIT​, it must also contain at least one of GL_MAP_READ_BIT​ or GL_MAP_WRITE_BIT​.
  • If flags​ contains GL_MAP_COHERENT_BIT​, it must also contain GL_MAP_PERSISTENT_BIT​.

Notes

If data​ is NULL​, a data store of the specified size is still created, but its contents remain uninitialized and thus undefined.

Errors

GL_INVALID_ENUM​ is generated if target​ is not one of the accepted buffer targets.

GL_INVALID_VALUE​ is generated if size​ is less than or equal to zero.

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 properties requested in flags​.

GL_INVALID_VALUE​ is generated if flags has any bits set other than those defined above.

GL_INVALID_VALUE​ error is generated if flags​ contains GL_MAP_PERSISTENT_BIT​ but does not contain at least one of GL_MAP_READ_BIT​ or GL_MAP_WRITE_BIT​.

GL_INVALID_VALUE​ is generated if flags​ contains GL_MAP_COHERENT_BIT​, but does not also contain GL_MAP_PERSISTENT_BIT​.

GL_INVALID_OPERATION​ is generated if the GL_BUFFER_IMMUTABLE_STORAGE​ flag of the buffer bound to target​ is GL_TRUE​.

Associated Gets

glGetBufferSubData

glGetBufferParameter with argument GL_BUFFER_SIZE​ or GL_BUFFER_USAGE​

See Also

glBufferData, glBindBuffer, glBufferSubData, glMapBuffer, glUnmapBuffer

Copyright

Copyright © 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/.