When I stream a buffer it tends to glitch and perform poorly. Whats the best way to stream a buffer?
When streaming audio into a buffer there are two basic algorithms: After-Write-Cursor (AWC) and Before-Play-Cursor (BPC). AWC minimizes latency at the cost of glitching, whereas BPC is the opposite. Because there are usually no interactive changes to the streamed sound this sort of latency is rarely a problem for games and similar applications, so BPC is the more appropriate algorithm. In AWC, each time your streaming thread runs you “top up” the data in your looping buffers up to N ms beyond their write cursors (typically N=40 or so, to allow for Windows scheduling jitter). In BPC, you always write as much data to the buffers as possible, filling them right up to their play cursors (or perhaps 32 bytes before to allow for drivers that incorrectly report their play cursor progress). Use BPC to mimimize glitching, and use buffers 100ms or larger even if your games doesn’t glitch on your test hardware, it will glitch on some machine out there.
