maxton / jam.net Goto Github PK

Now that the ADPCM is decoding properly, there should be audio export features. I have some ideas:

• Right click a song/songs in the library -> Export audio as -> (FLAC / WAV / AIFF / OGG)
• In the Score window, add a menubar, which has an Export option

Current location for the contentCache file is %LOCALAPPDATA%., which is too generic.

Move it to %LOCALAPPDATA%\Jam.NET\contentCache.xml

Additionally, the User settings (currently only the location of the content folder) should be moved to the same place instead of using the built-in user settings functionality.

So,

• %LOCALAPPDATA%\Jam.NET\contentCache.xml
  and
• %LOCALAPPDATA%\Jam.NET\settings.xml

SoundTouch is a great library for this - it's LGPL licensed, and has .NET bindings available.

If a song plays to the end and goes back to the start, (or if you seek near the end, seek back, and wait for however many seconds the end would have arrived in), no data seems to be coming out of the wave streams anymore (the click track is still generating clicks, though). Look into why this is happening (maybe the ADPCM decoders aren't getting re-wound for some strange reason)?

• Offset the waveform by 50%
• Add a "now line"/playback cursor
• Add a horizontal centerline

May necessitate adding some more public interface members to the Fader control

Could be useful to be able to connect to a Jammit server should it or a clone ever re-appear.

Some API endpoints:

Username/device check

https://[store.server]/scripts/ddidcheck.php?uname=[username]&evje=[device id]
Called before getting user info.
Returns: 0, 1, or 2.
0 : success.
1 : Incorrect username
2 : Account has been deauthorized for the device

Get user info

https://[store.server]/jammit_app_data?username=[username]&password=[password]
Returns a bunch of stuff separated by ~~ (at least 31 items). If that's not what is returned, then the password was invalid.
Subtract 32 from the 31st item to get the Jammit ID (account ID).

Login?

https://[store.server]/ddmailregister.php?jammitid=[account id]
Called after getting user info but the return value, if any, doesn't seem to be used at all.

Deauthorization

https://[store.server]/scripts/ddtkill.php?vje=[account id]&evje=[device id]

List of content UUIDS

https://[server]/scripts/ddtv1.php?vje=[account id]&evje=[device id]&bld=[build]&typ=[os version]
Returns uuids for the given account/device combo, separated by ^^ for some reason. These are then downloaded from https://[store.server]/sites/default/files/[uuid].zip.
After the uuids, there is %% followed by something else.
If there are none(?), it returns "noid". If there are too many authorized devices, it returns "*3max"

It would be very convenient for the app to run in mobile platforms, such as Windows Universal iOS and Android.
I already have ongoing work on this at https://github.com/JunielKatarn/Jam.NET/tree/mobile.

Considerations:

• The UI must be fully re-implemented. The current .NET Desktop (Windows.Forms) code can't be reused on mobile.
• Xamarin.Forms provides a viable framework to code once and deploy to the three mobile platforms.
• Xamarin.Forms relies on PCLs (stripped-down .NET framework libraries, which have many limitations in terms of API access as opposed to regular .NET).

I think the Song class should handle this when you instantiate it.

Beatmap can probably just be parsed to a list of beats.
Beat structure:

• Time (double)
• IsDownbeat (bool)
• IsGhostbeat (bool)

Sections to a list of sections:

• Beat index (or better, a reference to the beat)
• Number (int) -- what is this?
• Type (parsed to a string).

I imagine this will be done by the mixer keeping track of the peak voltage per track over some interval, and the fader polling that the same way the transport polls the current time.

Right now only the first notation file is displayed. As a user I want to be able to select between parts and between notation and tablature. I guess this can be done in the score control itself, or maybe in the containing form.

Once #7 is implemented, we can add section text to the waveform and the transport.

This should run in Mono, in theory, except for the audio API. NAudio relies on WASAPI and/or other windows-only libraries to get audio out of the speakers. Look into another audio library. I think maybe PortAudio would be best, I think it has .NET bindings somewhere, otherwise, possible BASS.NET, although that is non-free. If anyone knows of some other audio APIs, I am all ears.

The decoded audio is noisier than what you get from FFmpeg. Look into the decoding algorithm.

Things like refreshing the library cache are slow and lock up the UI thread. I think a popup window that runs a task will solve this problem nicely

Once #7 and #8 are implemented we can add looping to the app.

In the original client, the title of the song, the songwriters, the tempo, and the copyright are displayed at the top of the score.

This should be pretty simple to add in now that the score is centered both vertically and horizontally in the window.

Screenshot from the C++ windows client:

In order to allow for different formats (i.e., loose files as well as .zip content files), there needs to be loose coupling between Song and its interface.

• Create ISong with Song's public interface
• Move Song to ZipSong
• Create FolderSong for extracted files
• Change SongMeta and the Library to refer to songs by their filename/path in addition to their GUID
• Create a SongLoader static factory class that will return an ISong for a given SongMeta

As far as I can tell, this is generated using the info from beats.plist. So, once #7 is implemented it should be pretty simple?

This is a large feature. The end result is that we have an animated score like the original app.

• Reverse-engineer the format of nowline.nodes
• Write a parser
• Implement scrolling
• Implement the "now line" on the score

I'm not sure how well this will end up working, as it depends on the latency of NAudio. Probably some latency compensation will be required. Although, the original app was pretty bad at this anyway...

It's pretty ugly overall right now. It would be nice if it were not so ugly.

• Fix the time slider to allow seeking while the song is playing.
• Add jump forward/backward buttons to move quickly between sections.

This one's pretty difficult to do correctly. I would say it is low priority.