As discussed in !1725, there is an init order issue, which is that you
cannot obtain any of these ID objects as long as the GimpProcedure is
not created. In particular, now that GimpResource arguments can have
defaults, we will want to query such resource in the create_procedure()
implementation of a plug-in (where the GimpProcedure is not running yet,
as we are defining it!).
Anyway I don't really see the point of these multiple-level hash tables
all storing a reference to the same object. Let's just store in the
GimpPlugIn's hash tables once and give the same reference to any
procedure (anyway we make it clear that these objects belong to libgimp
and must not be freed, so it's a bug all the same if someone frees
them). Then it also fixes the init order issue.
All the functions working with object's IDs are mostly internal. They
are still made public because they can be useful and are relevant in
specific use cases (i.e. using IDs to reference items in specific
widgets, such as drop-down lists, or when temporarily storing an item as
integer, etc.).
Yet it should be made clear that these usages are the exception rather
than the norm.
Even when the function names may have stayed the same in most cases, the
API has changed. The "Since:" tag must therefore be bumped.
Also adding docs for gimp_drawable_get_sub_thumbnail_data() which had
none.
- hand out and leak proxy object objects to legacy API like candy,
bypassing the factory in GimpPlugIn, because there is no plug-in
singleton.
- gimpgpcompat.c: image, item etc. are now objects, simply forgot this
file.
Turn all ID param specs into object param specs (e.g. GimpParamImageID
becomes GimpParamImage) and convert between IDs and objects in
gimpgpparams.c directly above the the wire protocol, so all of app/,
libgimp/ and plug-ins/ can deal directly with objects down to the
lowest level and not care about IDs.
Use the actual object param specs for procedure arguments and return
values again instead of a plain g_param_spec_object() and bring back
the none_ok parameter.
This implies changing the PDB type checking functions to work on pure
integers instead of IDs (one can't check whether object creation is
possible if performing that check requires the object to already
exist).
For example gimp_foo_is_valid() becomes gimp_foo_id_is_valid() and is
not involved in automatic object creation magic at the protocol
level. Added wrappers which still say gimp_foo_is_valid() and take the
respective objects.
Adapted all code, and it all becomes nicer and less convoluted, even
the generated PDB wrappers in app/ and libgimp/.
Turn GimpPlugIn into the main factory for all proxies and keep the
main hash tables there. The hash tables keep the initial reference.
For each GimpProcedure::run(), have s "sub-factory" which hands out
proxies to the actual procedure code. Each run() has hash tables of
its own which hold additional references. When run() is done, get rid
of its hash tables and their references, *and* drop the main plug-in
reference counts from the global hashes if the proxies' refcount has
dropped to one.
No need of is_id_arg() anymore in pdb/lib.pl. Let's reuse the {id}
value. Also I had to add an additional trick for GimpDisplay which we
will now generate as such in libgimp PDB files, but still need to show
as GimpObject on app/pdb/.
As previously, only the new classes and the PDB generation for a first
step.
