The RecoderUI can show device input meters as long as a backend is
running regardless of a session. I/O Plugins are however
part of a specific session.
This is based on code from earlier commits that were later reversed, but we need some mechanism
to ensure that threads have a thread local tempo map ptr set. The big difference is that this
time we do not implement this for all instances of an AbstractUI - implementation is left to
each thread/event loop
* control points that were already closer than one_tick_in_pixels
were able to move beyond adjacent points, resulting in out-of-order lines
* prior code was using 'one tick' as the smallest spacing between two
CPs, but that is larger than the default 'guard point' spacing. this
resulted in odd behavior because of the dxt calculation when you moved
a point that was created as a 'guard point'
For now, use the same 64 samples we use for 'guard points'. And change
the 'dxt' calculation logic to more aggressively limit the points from
overlapping.
TODO: we might decide that 'one tick' should be the minimum automation
period throughout ardour. In that case we should change guard-points.
* in the case where there are no existing automation points, then
initiating an automation range drag (select range, switch to Draw)
should initialize the line at the current knob position
Stem-export defaults to use selected tracks. This retains
the selection, so focus remains. Repeat stem export will use
previously exported tracks if the selection is empty, or the
current selection (again).
Events in the delay-buffer must be shifted back every cycle.
Also in case of fixed-delay-lines events may not be in sequence
since events are only sorted at backend port-level.
citations are needed to explain when&how this is useful
the definition of Ripple is "accommodate cut/insert/moves by moving all
regions to the 'right' (later) of the operation by the same amount".
moving markers to the 'left' of the grabbed_region explicitly breaks the
definition of ripple. it makes documentation hard.
furthermore, in a more complicated session with multiple tracks, this behavior
ignores the regions on other tracks and the markers that still might be
associated with them (consider the case where you move the first region
on track A but there are many prior regions on track B with markers over
them)
this solves the oft-recurring problem where we assign
a beat-count of '3' or '7' because minipm mis-detected the tempo,
and that situation is vanishingly rare. it's better to assume 4 or 8
the user always has the option to change the number of beats (and
therefore the detected tempo) manually, for those clips that are
in a different time signature. but minibpm cannot be expected
to help us there.
NOTE: this is a fallback to make things 'just work' lacking any other context.
* if the tempo is detected in the filename, we use that instead
* clips that were recorded to the timeline use that bpm+timesig
* in the future we can use file-metadata (acidized wave?) instead
* this is audio-only: midi files can have an embedded timesignature
but... given no other information, experience says the vast majority
of downloaded/purchased clips will be 1,2 or 4 bars at 4/4.
omega can be computed from Beat or superclock duration. This gives rise to
different units for omega, and we must use the correct value in a given
context.
This commit also changes the way that the audio time omega is computed during
TempoMap::reset_starting_at()
