This module corresponds to chapter 6 (Buffers) of the OpenAL Specification
and Reference (version 1.1).
A buffer encapsulates OpenAL state related to storing sample data. The
application can request and release buffer objects, and fill them with
data. Data can be supplied compressed and encoded as long as the format is
supported. Buffers can, internally, contain waveform data as uncompressed or
Unlike source (see Sound.OpenAL.AL.Source) and listener (see
Sound.OpenAL.AL.Listener) objects, buffer objects can be shared among AL
contexts. Buffers are referenced by sources. A single buffer can be referred
to by multiple sources. This separation allows drivers and hardware to
optimize storage and processing where applicable.
The simplest supported format for buffer data is PCM. PCM data is assumed to
use the processor's native byte order. Other formats use the byte order
native to that format.
At this time, buffer states are defined for purposes of discussion. The
states described in this section are not exposed through the API (can not be
queried, or be set directly), and the state description used in the
implementation might differ from this.
A buffer is considered to be in one of the following states, with respect to
- The buffer is not included in any queue for any source. In
particular, the buffer is neither pending nor current for any source. The
buffer name can be deleted at this time.
- The buffer is listed in the queue of at least one source, but
is neither pending nor current for any source. The buffer can be deleted as
soon as it has been unqueued for all sources it is queued with.
- There is at least one source for which the buffer has been queued,
for which the buffer data has not yet been dereferenced. The buffer can only
be unqueued for those sources that have dereferenced the data in the buffer
in its entirety, and cannot be deleted or changed.
The buffer state is dependent on the state of all sources that is has been
queued for. A single queue occurrence of a buffer propagates the buffer state
(over all sources) from unused to processed or higher. Sources that are
in the Stopped or Initial states still have queue entries that cause
buffers to be processed.
A single queue entry with a single source for which the buffer is not yet
processed propagates the buffer's queuing state to pending.
Buffers that are processed for a given source can be unqueued from that
source's queue. Buffers that have been unqueued from all sources are
unused. Buffers that are unused can be deleted, or changed by writing