The user can now replay *all* earlier selection operations until the next
session undo/redo command, or the completion of a new operation.
Nothing relating to selection ops is stored, and selection operation history
is begun on first idle.
Selection operation history is fundamentally different from the history of
operations which act on a selection in terms of both their viewport and the
amount of information required to replay them.
WRT undo, the user of a selection op doesn't care about the viewport state
at the beginning of an op, but rather that at the end of the previous one.
This cleans up a lot of false-positives in static analysis
and also helps compilers to optimize code paths in general.
(tagging the fatal stingstream operator as ‘noreturn’ is
far less trivial)
All the different looks here didn't seem to convey anything useful to me, and
looked sloppy. I went with the style of the transport button.
It would be nice if we could style button elements like Inset in the
configuration, but this would require some work.
This is needed to be able to lock the application fully on OS X, where the global menu bar would still allow interaction
even when a modal dialog is displayed.
Add a value for Ripple to EditMode enum.
Add Ripple edit mode to edit mode dropdown, by adding it to the
Editor::build_edit_mode_menu() helper function, and remove the old code that
added items to the (now unused) Editor::edit_mode_strings.
Add the regions that should be affected by the drag to RegionDrag::_views so
that the drag carries them along automatically.
Use a copy of the RegionList in Playlist::core_ripple(), since bad things
happen when iterating over regions and they get moved around in the list.
Handle rippling in removal of regions from playlist.
When dragging in ripple mode, exclude all regions that lie before the
original start position of the selected regions being dragged from
rippling: this is what Mixbus does.
Make editor dragging respect snap-to settings, by using the existing
compute_x_delta() function, which did almost the right thing. Move setting
of _last_frame_position out of that function so all ripple-dragged regions
can move.
Ripple when dragging from region list: even though Mixbus doesn't do this, it
seems like a good idea.
Prevent multi-track selection being dragged across tracks, by making
RegionMotionDrag::y_movement_allowed() virtual, and overriding it in
RegionRippleDrag to forbid dragging of selections containing regions on more
than one track to dofferent tracks in ripple mode.
Remember which TimeAxisView a ripple-mode drag that's allowed cross-track
drags started from, so that the effect of rippling regions after any region
that's dragged off that track can be undone.
