* Fix reset on timeout: Reset needs to be called before
processing any messages.
* use DLL to compute BPM (remove 1st order LPF)
* set BPM before calculating ppqn
* Fix speed at 1.0, change BPM only. MIDI clock must
vari-speed (which changes pitch). MIDI clock is acts as
"Conductor" that specifies when a beat happens at a given
wall-clock time. timecode moves at speed 1.0 only the BPM
changes.
* Honor MCLk stop messages, do not auto-start as soon as
the tempo is locked (after 3 clock ticks).
* Retain MIDI beat position, do not rewind in ::update_midi_clock
Do not directly start when receiving the position message,
transport speed should be zero (regardless of clock speed),
until the "continue" message arrives.
* Mclk start needs to rewind (not reset)
There is still an issue with start, when
_session->transport_sample() is not zero. Ardour ends up
constantly locating, rolling for a short time and re-syncing
by locating again.
For normal cairo-widgets ardour should not use image surfaces on macOS,
because that bypasses retina scaling. In theory explicit upsampling could
be performed (compere to openGL/cairo), but for the case at hand that is
overkill and inconvenient.
Performance critical widgets that render periodically can enable openGL
backing. Casual widgets (buttons with text, knobs, sliders etc) can be
rendered directly without any significant performance penalty.
Some plugins call back to restartComponent() directly from
IEditController::setComponentState.
This lead to a deadlock since VST3Plugin::load_preset
takes a lock (since 7.2-85 b27467157b), and restartComponent
takes the same mutex again.
This fixes an issue with Blendeq (and likely other plugins)
that call `restartComponent(Vst::kLatencyChanged) from the
in realtime context from plugin's process
* HitCreateDrag::start_grab does not need to do anything
a hit cannot be past end of region. Drawing at or past
the end of a region will create a new region (not an event)
* HitCreateDrag::finished now calculates the position like
NoteCreateDrag::finished.
* the selection does not need to be cleared. Creating new
notes/hits selectes the newly created ones.
e.g. loading a u-he zebra preset using the plugin's GUI
internally changes the controller state without using the
`performEdit` API, but instead calls `restartComponent` wit
the `kParamValuesChanged` flag to perform a a batch update.
This now also updates Ardour's AutomationControl to match.
