Apparently some raw lingering pointers to the item widgets may be
present inside of the QListView if you delete the item widgets directly,
and the only way to ensure those pointers are properly cleared is to
call ->clear() on the list widget instead of deleting each item
individually.
We were deleting each item individually because we thought that
->deleteLater might be also be called on other data within, but after
some testing, that turned out to not be the case, so it's safe to call
->clear() on the list widget.
As a note, deleting item widgets directly is dangerous due to the
potential for lingering raw internal pointers, and our case is unique
where we can get away with it; do not delete list item widgets directly
unless you intend on calling ->clear() or ->takeItem on the specific
item you do it to after.
Again, the reason why we are deleting list widget items manually is due
to the fact that Qt will always use ->deleteLater() on them if they are
not deleted manually, which puts their deletion on the queue. Only
problem is they cannot be removed from the queue once added, so
lingering references to sources will persist until the queue processes
them, which causes major problems if we need those objects deleted right
away.
When initializing with a default scene, save the data to ensure a file
is actually present when needed (such as for scene collections which may
need the file)
Add a central function for clearing all data: scenes, sources, widgets
such as lists that may contain source references in their sub-items,
dialogs which may contain source references. In certain circumstances
this data must be fully released and manually freed to ensure that there
are no outstanding references to obs data (such as on shutdown, where
all data should be properly freed).
These functions are designed to manually delete item widgets within
other widgets to prevent ->deleteLater from being called on them. This
prevents the item widgets from being stuck in the event queue, and
prevents references to things like sources from being stuck in the event
queue along with them if they're used in the item widget's class or
functions.
Right now, information about global audio sources is stored in both
scene files and in the config. These must be separated; there's no need
to store them in both when they can just be stored in the scenes file.
System timestamps were being used instead of timestamps from the
audio/video input. This would cause potential desync as well as
incremental buffering when using devices with the blackmagic video
source. Using the timestamps direct from the SDK itself fixes those
issues, and causes audio/video to play back properly and in sync.
When using e.g. a color correction filter on any source and changing
any value (with slider enabled, e.g. contrast) to -0.10 the value would
get cycle between -0.07/-0.08 at some point when using the up arrow; it
would also get stuck on -0.69.
For the other direction, when starting from e.g. -0.02 the value would
jump from 0.05 to -0.08 when pressing the down arrow.
Problem was reported at https://obsproject.com/forum/threads/32450
The empty implementation for the QDataStream operators is necessary to fix
a Qt assertion: "QVariant::save: unable to save type
'std::vector<std::shared_ptr<OBSSignal> >' (type id: 1036)."
It doesn't seem like a full implementation of the stream operators would be
useful since the signal registration is very specific to the interaction
between the scenes and sources list, i.e. in case the scenes list ever accepts
scenes from sources (not 'obs_source's) other than itself (non InternalMove
drag&drop?) it would have to register those scenes with the libobs core which
should trigger the normal signal registration
This filter simply modifies the volume of the signal as a convenient way
of modifying the volume before other filters, or amplify the volume
without having to mess with advanced audio properties.
