We cannot call TempoMetric::superclock_at (BBT_Time) if the BBT time is beyond
the range of the current TempoMetric. We must discover that *before* we make
that call, not as part of the test to see if we've exceeded the range.
1. "not found" is now indicated by a timepos_t::max() value, not a negative one.
2. if the direction to search is negative we should decrement (when possible)
before searching, to avoid finding the current position.
This fixes a special case of the loop/punch ruler, which
only had effect on session-reload due to a copy/edit bug
(canvas_transport_marker_bar_event used "range marker bar")
There already is a shaded coverage frame indicating
if a layer is audible. This leads to a more consistent view.
In addition changing layered mode now has to update the
colors (set_frame_color).
This fixes rendering of opaque MIDI regions (previously
MIDI regions were always transparent). This change provides a
way to "flatten" layered MIDI regions, while still allowing
to show the note-line and grid behind the regions.
> This group functionality can be convenient for performing
> intermediate compositing. One common use of a group is to
> render objects as opaque within the group, (so that they
> occlude each other), and then blend the result with
> translucence onto the destination.
https://www.cairographics.org/manual/cairo-cairo-t.html#cairo-push-group
The main use case where will be to render opaque layered
[MIDI] regions transparently onto a grid.
Now that both Audio And MIDI tracks support all three record
modes. Monitoring should be consistent. When recording
"Sound on Sound" does cue monitoring, while "layered" (opaque).
and "non-layered" monitors only the input.
Two differences remain: (1) when not recording MIDI tracks still
monitor both Input and Disk (unless Non-layered is set), and
a final special case is that MIDI tracks always monitor input
as fallback. the latter ties in with (2) audio tracks can
use hardware monitoring.
