This is implemented on top of a Tree that represents the whole timeline.
SourceClips can not fully overlap anymore and the tests have been
updated to take that into account. Some new tests were added to verify
that behaviour in greater details
Each timeline element is in a layer (potentially spanning
over several), it is very often useful to retrieve an element
layer priority (from an app perspective more than the element
priority itself as that is a bit of an implementation detail
in the end).
Port tests to it
Auto transition when having 3 overlapping clips in a same point in the
timeline is not supported as we can't handle it in a nice way. Before we
to avoid creating 2 overlapping transitions (which is plain broken in
NLE) were completely disabling `auto-transition` and removing all
auto-transitions in the timeline but this is pretty weird for the end
user. This commit changes and now makes sure 2 transitions are not
created in the same place.
Also cleanup previous test case.
And start handling relocated assets.
Also expose the discoverer callback as a vmethod so that we can
overridde the discoverer when necessary (to handle discovering of
timeline through gesdemux for example)
When removing an effect from a clip, first the notify::priority signals
were being emitted for the remaining effects which changed priority, and only
at the end the child-removed signal. Now the child-removed signal is emitted
first.
Marking them as children properties and properly allow serializing
clips children properties.
This doesn't handle several TrackElement of a same type with
different property values but this require more worked already
marked as fixme to allow specifying full path of elements in the
children properties API.
See https://gitlab.gnome.org/GNOME/pitivi/issues/1687
Implementing it in the overrides as PyGObject won't be able to properly
convert python values to GValues in some cases. Using
g_object_set_property works as some logic is implemented inside
PyGObject for that particular case. This is a "regression" due
to https://bugzilla.gnome.org/review?bug=769789&attachment=348766 were
we end up with an OverflowError while setting G_TYPE_UINT children
properties.
In the (now tested) scenario where we have a transition on the right
side of a clip we are splitting, auto transitions can't be created
because we resize the clip after adding the new one, meaning that
there are 3 elements in the "transition zone", we need to force
auto transition creation after the splitting.
Fixes https://gitlab.gnome.org/GNOME/pitivi/issues/2142
