Sampler bank presets, save/load groups of tracks to sample decks

[rob]

The new sampler heavy skin has got me thinking about samplers a bit differently... They're not really usable the way I'm thinking about them yet, because there's no way to save sampler state (specifically, what tracks are loaded into the samplers), but I'm now thinking that you could set up a skin with 16 or more tiny samplers, load short loops and one-shot samples into them, and use them for on the fly remixing. This would sort of address one of the big holes in mixxx. But it's not practical to manually load 16 samples every time you want to play a song. We need a way to save the set of tracks as a "bank", and then reload them all later.

This could be hacked together with controller scripts if we, at minimum, had the ability to query a deck or sampler for the filename and location of the currently loaded song, and to force a deck to load a file by filename via script.

To fully implement this, we would also need a way for scripts to persistently save data that they could retrieve later. Perhaps space in the database could be created for "user data", allowing scripts to save arbitrary data for later retrieval, even after mixxx was restarted.

[RJ Skerry-Ryan (rryan)]

Not sure scripts are the answer until scripts can talk to the library but I totally agree we need to be able to save/load sampler state or add sampler presets of some sort. This was part of Ryan Baker's original sampler project but never got done.

[RJ Skerry-Ryan (rryan)]

The code is here.. it even kind of works?
https://github.com/mixxxdj/mixxx/blob/master/src/samplerbank.cpp

[RJ Skerry-Ryan (rryan)]

(for save/load of samplers to XML)

[RJ Skerry-Ryan (rryan)]

Actually, I think those even work. Jus -- how do you feel about adding this in 1.12.0?

[RJ Skerry-Ryan (rryan)]

The controls are:

[Sampler],LoadSamplerBank
[Sampler],SaveSamplerBank

[Owen Williams (ywwg)]

It looks like you wrote it at 2 in the morning :P

[RJ Skerry-Ryan (rryan)]

commit bc3fed81245f7e7302d67d6613855a42df85fdeb
Author: RJ Ryan <email address hidden>
Date: Sun Oct 24 22:56:22 2010 -0700

    Make SamplerBank for loading and saving sampler configuration (adapted from Ryan's code...

Well, it was 10pm but who knows how much sleep I had. 2010 was not a good year :P.

The XML could probably use some tweaking but it has group and track location which is mostly all that matters.

[RJ Skerry-Ryan (rryan)]

Maybe we could add things like sampler settings themselves to the XML (especially if we have sampler modes).

[jus (jus)]

Well, i tried to add the following to a skin:

<PushButton>
  <Size>40f,20f</Size>
  <NumberStates>1</NumberStates>
  <State>
    <Number>0</Number>
    <Text>Save Set</Text>
  </State>
  <Connection>
    <ConfigKey>[Sampler],SaveSamplerBank</ConfigKey>
  </Connection>
</PushButton>

<PushButton>
  <Size>40f,20f</Size>
  <NumberStates>1</NumberStates>
  <State>
    <Number>0</Number>
    <Text>Load Set</Text>
  </State>
  <Connection>
    <ConfigKey>[Sampler],LoadSamplerBank</ConfigKey>
  </Connection>
</PushButton>

I can put a file name for the sampler bank in the file dialog, but it segfaults on saving, no file is written to the disk.

Warning [Main]: Warning PlayerManager::getSampler() called with invalid index: 0
Process 94568 stopped
* thread #1: tid = 0x11fabe6, 0x000000010003ba7f mixxx`BasePlayer::getGroup() [inlined] QString(this=0x00007fff5fbfe3b0, other=0x0000000000000010) at qstring.h:726, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x10)
    frame #0: 0x000000010003ba7f mixxx`BasePlayer::getGroup() [inlined] QString(this=0x00007fff5fbfe3b0, other=0x0000000000000010) at qstring.h:726
   723 inline void QString::clear()
   724 { if (!isNull()) *this = QString(); }
   725 inline QString::QString(const QString &other) : d(other.d)
-> 726 { Q_ASSERT(&other != this); d->ref.ref(); }
   727 inline int QString::capacity() const
   728 { return d->alloc; }
   729 inline QString &QString::setNum(short n, int base)

[RJ Skerry-Ryan (rryan)]

Ah, you can really tell that code has never been used then :).

Fixed in https://github.com/mixxxdj/mixxx/commit/06b30d17536c2f63aaa5b3d15172a53f261be6af

[jus (jus)]

Thanks for taking a look at it.
Just pulled latest master and the segfault is fixed.

Now you can save a bank, but when loading the bank, it throws the error ``Could not read the sampler bank file``. The saved file is overwritten on load and corrupts (empty).

In the log, there is the following line:
Warning [Main]: QIODevice::read: WriteOnly device
2014-12-01 20:04:56.377 mixxx[4762:507] modalSession has been exited prematurely - check for a reentrant call to endModalSession:

This is with OSX 10.9.3

Notes:
By default, the banks are saved without file extension. Might be a nice touch to add *.xml or similar to allow sorting by file type in the file browser. Banks probably belong in the library just like playlist/recordings. But this is for Samplers 2.0 :-)

[RJ Skerry-Ryan (rryan)]

Pushed another couple of fixes -- this time I even verified that it works before pushing!

[jus (jus)]

Load/save Samplerbanks now available in the Deere skin, see https://github.com/mixxxdj/mixxx/commit/87d85f03cc0208dbe394a982615ae18fb6030fda

[jus (jus)]

Fixed in deere

[Swiftb0y (swiftb0y)]

Mixxx now uses GitHub for bug tracking. This bug has been migrated to:
https://github.com/mixxxdj/mixxx/issues/7043