This actually makes use of the client.h declarations and the mpv_node
mechanisms added some commits ago.
For now, using MPV_FORMAT_STRING will usually fallback to explicit
string conversion, but not in the other cases. E.g. reading a numeric
property as string will work, but not reading a string property as
number. Other than that, only MPV_FORMAT_INT64->MPV_FORMAT_DOUBLE does
an automatic conversion.
I'm not sure whether these semantics and API are good, so comments and
suggestions are welcome.
With mpv_set_property(h, "property", MPV_FORMAT_STRING, ptr), ptr now
has to be of type char** instead of char*. This makes it more consistent
with mpv_get_property() and also non-pointer formats, which will be
introduced in the following commits. mpv_set_property() of course does
not change its interface (only its implementation is adjusted to keep
its interface).
This also affects mpv_set_option(), but again not
mpv_set_option_string().
Add a client API, which is intended to be a stable API to get some rough
control over the player. Basically, it reflects what can be done with
input.conf commands or the old slavemode. It will replace the old
slavemode (and enable the implementation of a new slave protocol).