It is apparently how dependency names are supposed to be spelled to be taken
into account. The previous commits fixed some, but missed 2. I'm not sure they
will actually end up in the right-side list of the docs (it looks like when a
dependency is not actually found in the API, it isn't listed there), though it's
at least always listed in the left side, as I can see it.
And while I would prefer the upstream "display" name (i.e. GEGL and babl instead
of Gegl and Babl), better be consistent in how we list these dependencies in the
libgimp and libgimpui docs.
See discussion in !811.
The urlmap file allows gi-docgen to generate links for namespaces that
are also generated by gi-docgen. For example, with this commit, a
reference to `GObject` will now be properly linked to the GObject
documentation.
gtk-doc has been slowly dying for the past few years; with gi-docgen we
have a nice successor.
This also makes sure the C documentation also uses the GIR file, which
in turn means faster build times (since all the C code doesn't have to
be parsed and recompiled again), and has a clear dependency graph.
See the [gi-docgen tutorial] for more info on how the system works.
[gi-docgen tutorial]: https://gnome.pages.gitlab.gnome.org/gi-docgen/tutorial.html
