Ripple edit undo/redo needs a "recursive diff" of all regions
in the playlist. To work properly owned changes have to be
cleared first, previously unrelated edits were be collected too.
This includes a more consistent version of
7a89d56009 using rdiff() instead of explicitly
saving region diffs.
The undo command needs to be started before calling
playlist->add_region() because that may move automation
or include ripple changes. see the following backtrace:
```
UndoTransaction::add_command
ARDOUR::DiskReader::move_processor_automation
ARDOUR::Route::foreach_processor
ARDOUR::DiskReader::playlist_ranges_moved
ARDOUR::Playlist::flush_notifications
ARDOUR::Playlist::RegionWriteLock::~RegionWriteLock
ARDOUR::Playlist::add_region
Editor::bounce_range_selection
```
Except. it seems automation is moved incorrectly in this case..
* Consolidate access modifiers
* Remove all public member variables
* Only expose required functions, use private
whenever possible
* Rename private members, prefix underscore
* Remove cruft
This combines SessionEvent per playlist. Now per change
there are "only" two SessionEvent::Overwrite events
queued per playlist in the GUI thread for later processing
the Butler.
These are triggered by Playlist::ContentsChanged()
and Playlist::LayeringChanged(), both of which trigger
DiskIOProcessor::playlist_modified.
(Previously there used to be two per region)
playlist->partition() calls DiskReader::playlist_ranges_moved()
which may add Panner and Fader automation state changes.
The reversible command has to be started before calling
playlist->partition(). Simply collecting playlist->rdiff() after
the fact is not sufficient.
This is in preparation to subscribe to playhead cursor position
changes in the recorder-UI.
This change also clean up the API, replacing a public variable
with a const access method and follows #12 of
https://ardour.org/styleguide.html
The issue remains if a track is selected by a "fit-selection" action second
last track covers the whole trackview. Then when scrolling one track up, the
huge track disappears and a smaller track follows, that covers a lot less
space.
-> Proper redraw of the track view is still needed.
When the cursor position is after the last item in the vector,
upper_bound returns the last given iterator, here:
`region_boundary_cache.end()`, which is invalid to dereference.
Furthermore prevent possible duplicate prev/next pair at zero,
when using the video-timelime.
