Original code is of questionable historical provenance, and
was needlessly (it seems) complexity. New code is relatively
simple arithmetic linear interpolation.
Session dirs must exist when loading Sources of a project.
SourceFactory::init() starts the PeakFileBuilder background thread
early on when libardour is initialized.
This thread [re-]creates missing peak files when Sources are
created or loaded. However AudioSource::prepare_for_peakfile_writes
assumes the peak/ folder exists. This may not be true, which lead to
"AudioSource: cannot open _peakpath [..] (No such file or directory)"
errors.
Also drop creation from Source::get_transients_path() as this
may be called concurrently from Analyser background threads.
The fix here is really just dropping the use of _offset when computing the session position
of a control point. This was just an arithmetical error.
However, session_sample_position() was redundant and just caused more work, so this
method was removed, and only ::session_position() is now used.
In addition, several closely related places now use C++11 (or later) "auto"
syntax for iterating over containers, for cleaner looking code
This reverts commit 96ebac646d.
There are some valid cases where refill is called from the GUI
thread. e.g adding tracks, or adding channels to an existing track.
This happened initially during session load.
The GUI thread performed a direct refill (blocking wait)
`Session::post_engine_init() -> Track::seek() -> DiskReader::seek() -> DiskReader::do_refill_with_alloc()`
while concurrently the butler thread does the same:
```
Session::butler_transport_work() -> Track::non_realtime_locate() -> Route::non_realtime_locate()
-> DiskIOProcessor::non_realtime_locate() -> DiskReader::seek() -> DiskReader::do_refill_with_alloc()
-> DiskReader::refill_audio()
```
We do not want the GUI to wait, so now we just request a locate
and let refill happen in the background.
In case a user manually renames a session-folder and snapshot
it should still be impossible to delete the last snapshot
even if it is not named after the session-dir.
In theory this is impossible (one cannot delete the current snapshot)
Previously this setting was ignored. It is relevant when loading a demo
session, where initially there is no user Config instant.xml.
ARDOUR_UI::setup_windows is called directly after the engine starts, but
before the session is set.
Region actions are generally set insensitive whilst recording, so
special-case the "add-region-cue-marker" action by explicitly enabling it
when starting to roll in record. Additionally, the action becomes disabled
again after it's been executed, so re-enable it after queuing the cue when
recording.
Add a list of marker locations to the session, for the the UI to add the
current location to when "add-region-cue-marker" happens whilst recording.
On record-stop, create source markers at the locations in that list in all
newly-recorded audio regions.
This change still runs the triggerbox during latency-preroll, but as with the disk reader,
the transport speed argument is set to zero. The triggerbox notices this and behaves
appropriately (I think !)
