The old code used the instantaneous tempo at T0 to compute where the next
quarter note would be. This is incorrect, since the tempo is
changing (continuously, for now) during the time represented by that quarter
note. Instead, we need to add a quarter note (or technically, whatever the
tempo note type is) to get a new position in beats, then compute the superclock
time at that location (which will use our equations for tempo, including the
use of omega, the ramp factor).
These comments should correct an impression left in the commit message for
6e9e28343bc3695d that there may be some sort of problem with synchronization
of TempoMap changes. The actual problem is that TempoMap edits are done using
RCU, so the modifications are performaned using a copy of the map, but with
map elements taken from the pre-copy version.
The correct algorithm is to traverse the type-specific list of points,
find the point (if any) whose time matches that of the argument (because
we do not allow multiple points of the same type at the same time), and
then use that discovered point from the _points list.
This approach is required because the actual argument may no longer be
in the tempo map (due to a change made by another thread). The lack of
sync, however, needs investigation.
* Draw antialised waveform if waveform is monotonic
* Fix center-line position (span at most height - 1),
* Remove invalid "side-lines" that were previously
drawn around spikes.
* Do not linearly center min/max when drawing log-scale
* Fix offset of lower outline and clip indicators
This was changed in fc9840f2a9 to hard code a "false" argument describing
whether or not the child bbox had changed. This causes the parent to not
recompute its own bounding box when a child is shown/hidden, which is
incorrect. We now force it to true, which may be overkill for some purposes,
but at worst will just force an unnecessary bbox re-computation and nothing
more.
When loading a session, we now just set up port state, which will
populate the Port::_connections member, and then once all ports have
been created, use PortManager::reconnect_ports() to get everything connected.
If connecting ports using the port-engine fails,
ardour forgets the connection.
Internal backends only produced an error if a port was already
connected, when using ::connect (handle, other), but
ignore already existing connection when using port-names.
Various ports are connected twice when the engine connects
at session load. This worked fine for as long as the engine
was never stopped (saving the session asks the port-engine),
but failed when the engine went away and internal representation
is used.
