Attributes Specific to Queueing
Buffer Traversal
The Buffer traversal attribute specifies the direction in which the sample in the buffer is supposed to be processed. To account for the 3 basic modes of traversal that can be implemented in software and hardware, the following tokens are defined:
LOOP_DIRECTION /* traversal direction */
FORWARD /* linear forward (increment) */
BACKWARD /* linear backward (decrement) */
FORWARD_AND_BACK /* RESERVED: ping-pong-looping */
 | Annotation (Ping-Pong postponed) |
|---|---|
Definition and implementation of ping-pong looping has been postponed. Applications can fake it at doubling memory expense by reverse copying the buffer (2nd buffer queued or in a double size single buffer). Presuming hardware support, AL will have to support it eventually though. A boolean flag is not acceptable because of this possibility. |