- don't add a new SysEx canvas item every time we zoom or drag.
- speed up redisplay generally using PatchChange-like method
for finding items (find_canvas_sys_ex() in boost::unordered_map).
snap now fills in a struct (MusicFrame) which contins a snapped frame
along with a music divisor.
this gives useful information wrt magnetic snap which may or may not
have rounded to an exact musical position.
region position may now be set musically (using quarter notes for now).
this patch fixes several problems in the current code:
- dragging a list of music-locked regions now maintains correct
musical offsets within the list.
- splitting regions using magnetic snap works correctly (#7192)
- cut drag should now work correctly with magnetic snap.
- musical length of split midi regions is no longer frame based.
It is slightly questionable whether type specific methods like
velocity() belong on Event at all, these may be better off as free
functions. However the code currently uses them as methods in many
places, and it seems like a step in the right direction, since, for
example, we might some day have events that have a velocity but aren't
stored as MIDI messages (e.g. if Ardour uses an internal musical model
that is more expressive).
In any case, the former inheritance and plethora of sloppy casts is
definitely not the right thing.
- this allows a midi region drag to update the visible notes
correctly while crossing MIDI streamviews with a differing
note range.
as a side effect, fixes a bug where changing
note range on a track did not draw some notes
(apply_note_range redisplays the model).
- add more debugging output detecting regions whose
beat and frame position do not align on a playlist.
this is required as a check as we have never used
frame rounding on constant tempi before 8884a5723dc
- hide ghost note when add dragging.
- new note length snaps as per ghost note start (shifted snap).
- prevent ghost note from appearing before region start.
- Evoral::Beats operator!= would prevent an increment
of start_beats by intervals of less than a tick,
so its possible that other subtle problems
existed due to this kind of thing.
