Re: CN: www/2009/devdocs/XFP-SOD-CrossFadePlayer.doc

I have one more question about this.

I've setup the plugin as described and the IHXCrossFadePlayer implements 
IHXContextUser.  Its RegisterContext() is called, but when I try to QI 
the IUnknown context for IHXClientEngine I get a "no interface" error.

Is there something else I should do to get the client engine?  Or should 
I use a different mechanism to pass the client engine in to the 
crossfade player?

thanks!



Eric Hyche wrote:
> Nick,
> 
> Sorry for the delay in providing feedback. Here's mine:
> 
> 1) I like client/xfadeplayer instead of client/xfadeplugin,
>    although whatever you choose will be fine.
> 
> 2) Inside of client/xfadeplayer, I would have two sub-Umakefil's:
>    one that builds the IHXCrossFadePlayer into a static lib,
>    and the other sub-Umakefil that builds an Atlas component
>    plugin (and links in the static lib built in the other 
>    sub-Umakefil).
> 
>    A component plugin is one that implements IHXComponentPlugin.
>    This interface tells the media platform that this plugin
>    can create certain CLSID_xxx's. It specifies how many CLSID_xxx's
>    it can create via IHXComponentPlugin::GetNumComponents()
>    and it provides the list of CLSID_xxx's via
>    IHXComponentPlugin:: GetComponentInfoAtIndex().
> 
>    The IHXCrossFadePlayer object should also implement IHXContextUser.
>    That way, when the plugin handler creates it, it will automatically
>    pass it the context via IHXContextUser::RegisterContext.
> 
>    See client/netwksvc/hxnetwksvcpln.cpp, client\autoupgdmgr\autoupgdpln.cpp,
>    client\downloadmgr\downloadpln.cpp, or client\core\hxmedengpln.cpp
>    for examples of component plugins.
> 
> 3) When an application uses an IHXPlayer, then it:
> 
>     - loads the media platform
>     - QI's the media platform for CCF
>     - uses CCF to create IHXClientEngine
>     - uses IHXClientEngine to create IHXPlayer
> 
>    So for IHXCrossFadePlayer, it will:
> 
>     - load the media platform
>     - QI the media platform for CCF
>     - use CCF to create IHXCrossFadePlayer. The plugin
>       handler will make sure that the object gets a context
>       via its IHXContextUser::RegisterContext() method.
>       The context that it is passed will *be* the media
>       platform.
> 
>    There is no need to specifically have the application create
>    a client engine and pass it to the IHXCrossFadePlayer object.
>    The crossfade player object has a context, so it can create
>    a client engine internally itself and then manage the
>    lifetime of that client engine.
> 
> 4) Under "Testing Provisions", I would suggest a command-line
>    test app in client/xfadeplayer/test. You could use splay
>    as a starting point for that, or better yet, use my dirt-simple
>    SHAPE (Simplest Helix Audio Player Ever) player at
>    clientapps\samples\shape as a starting point.
> 
> 
> Eric
> 
> =======================================
> Eric Hyche ([email protected])
> Principal Engineer
> RealNetworks, Inc.
> 
> 
>> -----Original Message-----
>> From: [email protected] [mailto:[email protected]]
>> On Behalf Of Nicholas Hart
>> Sent: Wednesday, February 18, 2009 4:48 PM
>> To: [email protected]
>> Subject: Re: [Helix-client-dev] CN: www/2009/devdocs/XFP-SOD-CrossFadePlayer.doc
>>
>> there has been zero commentary on this proposal.
>>
>> I'm at a point where I'd like to start checking in some files.  The
>> project is by no means finished, but I'd like the security of keeping my
>> work in CVS in case my hard drive gets fried.
>>
>> Should I start submitting some code reviews to this alias?
>>
>> Thanks!
>>
>>
>>
>>
>> Nicholas Hart wrote:
>>> Modified by: [email protected]
>>> Reviewed by:
>>> Date: 2/11/09
>>> Project: internal RealNetworks product
>>>
>>> Synopsis: SOD for client feature to enable cross-fade and gap-less
>>> playback of audio clips
>>>
>>> Overview: I've committed a SOD for a new player object which uses the
>>> client engine to perform a cross-fade between two audio clips.
>>>
>>> Files Added:
>>> [File 1]
>>> https://helixcommunity.org/viewcvs/helix-client/www/2009/devdocs/XFP-SOD-
>> CrossFadePlayer.doc?view=log
>>> - SOD for this feature
>>>
>>> Platforms and Profiles Affected:
>>> none - SOD only
>>>
>>> Platforms and Profiles Functionality verified:
>>> none - SOD only
>>>
>>> Branch:  HEAD
>>>
>>> Copyright assignment:
>>>
>>>    4.      I am a RealNetworks employee or contractor
>>>
>>>
>>>
>>> _______________________________________________
>>> Helix-client-dev mailing list
>>> [email protected]
>>> http://lists.helixcommunity.org/mailman/listinfo/helix-client-dev
>>>
>>>
>> _______________________________________________
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> 
> 
>