[mythtv] [mythtv-commits] Ticket #4412: remove Win32 dependancy on directX headers from DXSDK

[Robert McNamara]

On Thu, Sep 2, 2010 at 8:32 AM, Jeff Lu <jll544 at yahoo.com> wrote:
>>  Is anyone using DX sound output that has a  critical reason for needing it?
>
> I'm probably the only one using it, given that "Windows" is more intuitive than
> "DirectX" (more accurately waveOut and DirectSound, respectively, but all the
> same).  Compared to waveOut, DirectSound gives me more consistent A/V sync
> during playback.  I find that waveOut slowly drifts in and out of sync, not by
> much, but enough for me to notice.
>
>
> Could be just a code issue - MythTV's AudioOutputWin class uses 50ms chunks for
> timing, so playback position is indeterminate within those chunks (+/- some ms
> for Windows message handling).  DirectSound API is designed to provide precise
> timing and works fine, so I haven't looked into improving the waveOut
> implementation.
>
>
>>  It seems that standardizing on the better  support audiooutputwin
>>  ("Windows:") method would be both more intuitive and  better supported.
>
> If by better supported you mean that waveOut headers are included in MinGW, then
> OK, I can see that.  (DirectSound headers are absent from MinGW for legal
> reasons.)  waveOut actually is the older and longer-depreciated API, but of
> course, neither it nor DirectSound is going away anytime soon.
>
> All that said, I can understand the desire to simplify the build script and not
> to maintain two audio classes for Windows.  If the decision is to drop
> DirectSound, so be it, but as you can imagine I'll be reverting the change
> locally.

Thanks Jeff, that's just the kind of input I was looking for.  With
that in mind, I don't see a compelling reason to drop either.  I do
think that defaulting to the more current and well supported API is
minimally the right User Interface decision, so I'll think about
taking that as the easier step.  I was looking at the code of both
output classes and I am fairly certain that there's a lot more DirectX
sound functionality that we can/should be taking advantage of, but
looking at that is going to be somewhere lower on my list of things to
do, the list is too long already.

K, so, for now, DX output stays IMO.

Thanks,

Robert