Not sure about this... might redo.
At least this provides a case of a broadcasted event, which requires
per-event data allocation.
See github issue #576.
There are some complications because the client API distinguishes
between integers and floats, while Lua has only "numbers" (which are
usually floats). But I think this should work now.
This is simply not important enough to warrant so much space, and it's
perhaps also very confusing.
Although I'm not fully sure, since this is about the only way that
allows a user to interact with a script, besides key bindings and static
options.
There was already an undocumented mechanism provided by
mp.set_key_bindings and other functions, but this was relatively
verbose, and also weird. It was mainly to make the OSC happy (including
being efficient and supporting weird corner cases), while the new
functions try to be a bit simpler.
This also provides a way to let users rebind script-provided commands.
(This mechanism is less efficient, because it's O(n^2) for n added key
bindings, but it shouldn't matter.)
Instead, chain them.
Note that there's no logic to prevent the other event handlers to be run
from an event handler (like it's popular in GUI toolkits), because I
think that's not very useful for this purpose.
This is preliminary. There are still tons of issues, and any aspect
of scripting may change in the future. I decided to merge this
(preliminary) work now because it makes it easier to develop it, not
because it's done. lua.rst is clear enough about it (plus some
sarcasm).
This requires linking to Lua. Lua has no official pkg-config file, but
there are distribution specific .pc files, all with different names.
Adding a non-pkg-config based configure test was considered, but we'd
rather not.
One major complication is that libquvi links against Lua too, and if
the Lua version is different from mpv's, you will get a crash as soon
as libquvi uses Lua. (libquvi by design always runs when a file is
opened.) I would consider this the problem of distros and whoever
builds mpv, but to make things easier for users, we add a terrible
runtime test to the configure script, which probes whether libquvi
will crash. This is disabled when cross-compiling, but in that case
we hope the user knows what he is doing.
