[Vala] GIO, GVfs, custom isolated URI handler

[Aleksandr Palamar <void995 gmail com>]

Hi, everyone.

I'm kind of new to GLib in general, but already have some basic
understanding of how it works. I'm planning to make a game using Vala
(which means GLib, GObject and GIO). One of the first things is to make
isolated VFS with different mount points on file system, each of has it's
own priority while looking for an existing file. I saw that GIO has
something for mounting and it's own GVfs, so may I extend/set up them in
some way to achieve my goal or that is totally another opera and I would
have to reinvent my own bicycle?

For example, while asking for file by URI resource://textures/blank.ktx it
will try to search for (sorted by priority):

~/.game/mod/textures/blank.ktx
~/.game/base/textures/blank.ktx
/opt/game/mod/textures/blank.ktx
/opt/game/base/textures/blank.ktx