When a tempo map change originates from a drag, we know the required redraws have
already been done. Use a new bool member, ignore_map_change, to tell the Editor
to ignore the map change signal. For all other map changes, do the full reset.
We now simply move markers during drags, and do not seek to create/delete markers.
When the map is changed, we rebuild the markers from scratch. This might need optimization to avoid doing
when the editor itself changed the map.
Previously it was possible that the tempo-curve display was rendered
above a tempo-marker (e.g. create a marker in the between of existing
markers). With the tempo-curve in front, markers on the right
became inaccessible.
Code used to just push back new markers to the end of the relevant list, and
this would then the new marker to be deleted soon thereafter. Instead pass
an interator indicating where to place the marker in the list.
Note that we rely on the use of std::list<T> here to keep the iterator to the
existing marker valid.
Since we're reconnecting visible marker objects with a new map, there's a good
chance that the map will contain map points that don't correspond to the map
points currently referenced by those markers. Thus, tests for address
equivalence will often fail.
Instead, repeat what has been done elsewhere and use the heuristic that we only
allow one point of a given type at the same superclock position.
This splits apart the actual signal handler from the work that needs to be done
to update the GUI in response to a tempo map change. This allows us to do the
visual update when we are manipulating the thread-local write copy of the map
during e.g. a drag operation.
This commit leaves two issues outstanding:
1. unclear/ugly semantics for drag operations that reset the GUI thread's tempo map to the writable copy
2. undo/redo for the tempo map
These will be addressed in future commits
Major changes: do not delete and recreate markers and curves for every tempo map
change, attach tempo curves directly to their (preceding) tempo marker, notable
cleanup of TempoCurve class to remove unnecessary members.
More tweaks expected since algorithm for matching markers and tempo map
points is not correct yet.
TempoMap::use() merely returns the current per-thread tempo map
pointer; if a change is signalled, we should force an update
of the per-thread ptr via TempoMap::fetch()
After beginning an edit operation with TempoMap::write_copy(), the tempoPoint and meterPoint objects
referenced by markers are incorrect, since they refer to the original map, not the copy we are working
on. Fix this with Editor::reassociate_metric_markers()
Some instances requiring this fix may still remain
