Composition save format

[Misty418]

For now, here are the composition informations we save.

{
 bpm: int,
 files: [ { name: string, size: int, type: string }, ... ],
 tracks: [ { id: int, isOn: bool }, ... ],
 samples: [ { uifile: string, duration: float, offset: float, when: float }, ... ]
}

Some informations are missing like filters.
We have to think about how we will save it and the webaudio nodes.
But for now it's not a problem since we don't use filters yet.

Here's an example:

{
 "bpm": 120,
 "files": [
  {
   "name": "128bpm - buffalonugaluss-blerg-bass.wav",
   "size": 2646178,
   "type": "audio/wav"
  },
  {
   "name": "140 bpm - siknoiz-the-water.wav",
   "size": 604948,
   "type": "audio/wav"
  },
  {
   "name": "150bpm - corruptionedm-another-generic-dubstep-beat.wav",
   "size": 1129138,
   "type": "audio/wav"
  }
 ],
 "tracks": [
  {
   "id": 0,
   "name": "Bass",
   "isOn": true
  },
  {
   "id": 1,
   "name": "Water",
   "isOn": true
  },
  {
   "id": 2,
   "name": "Beat",
   "isOn": true
  }
 ],
 "samples": [
  {
   "uifile": "128bpm - buffalonugaluss-blerg-bass.wav",
   "duration": 4.25,
   "offset": 10.75,
   "when": 1
  },
  {
   "uifile": "140 bpm - siknoiz-the-water.wav",
   "duration": 6.857142857142857,
   "offset": 0,
   "when": 0
  },
  {
   "uifile": "150bpm - corruptionedm-another-generic-dubstep-beat.wav",
   "duration": 6.4,
   "offset": 1.5,
   "when": 2
  }
 ]
}

[mr21]

Great!

I think it can be a good idea if we try to compress the file.
The most important is to know there will be only one "bpm", only one "files", "tracks" and "samples", but for the others, they will be numerous!
So I suppose it will be better if we stock the informations with array.

{
 bpm: int,
 files: [ [ name(string), size(int) ], ... ],
 tracks: [ [ id(int), toggle(bool) ], ... ],
 samples: [ [ fileId(int), when(float), offset(float), duration(float) ], ... ]
}

An another great gain of space is to use the file.id instead of the file.name.

The id of the tracks is because we don't save all the unused tracks right?

We have to save the track.id of each sample also.

[mr21]

We also have to stock a "timestamp" (in seconds, not ms) to let we all the possibility to manage the futur deprecated save files.