Hi RJ, On 20-Nov-08, at 1:38 PM, Russell Ryan wrote:
> Hi everybody, > > Just an update on what I've been poking around at. > > I'm trying to figure out how to implement looping, and in the process > I've spent a lot of time staring at how EngineBuffer works. Anybody > with > some experience here please do chime in and correct anything I've > gotten > wrong or give background/history of some of what is in here. > > I made a brief summary of how EngineBuffer::process works. > Interestingly > enough, it actually has some looping code baked into it, and after > looking at it more and more it looks like it might have worked at one > point. Does anybody know if it ever did work? > > Furthermore, there's this 'crossfading' thing inside of > EngineBuffer. As > far as I can tell, the crossfading is supposed to happen when you ask > for a beat-synchronized loop so that there is less abrupt jumping > between the end of the loop and the start. Does anybody know the > intent > or who wrote the crossfading stuff? (keep in mind, this is inside one > engine buffer, not crossfading between two enginebuffers). I think it's safe to say that nobody has any ideas about the old looping or "crossfading" stuff. You're more than welcome to just delete it, since it's not doing anything useful at the moment anyways. Your best hint might be to dig through the SVN log for enginebuffer.cpp, in particular, look before r899, which looks like the last time Tue touched that file. (On a side note, the comment for r429 will show you just how messed up their original design was.) :) Getting rid of the old crossfading/looping logic (as you appear to have done in your new EngineBuffer::process()) will go a long way towards cleaning up EngineBuffer. Other than that, as Adam mentioned, we brainstormed a bit about doing some intelligent caching of other parts of the song, the aim of which would be to help looping avoid hitting the harddrive in an RT thread. :) One tricky bit with the looping code that we've got in the branch is that when we tell the Reader to seek to a new spot, it runs asynchronously in a separate thread and then fill EngineBuffer itself with audio. So I think when we loop back to the start of a song, we're jumping to some point in EngineBuffer and praying that the Reader has filled it faster than us... (I think?) Thanks, Albert ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Mixxx-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/mixxx-devel
