have "sandboxes" preplanned pathes like in David Gage's creations? i thought that they hadn't...
No, in theory sandboxes are completely open. I am advocating against this openness. And in favour of authorship. But I don't think a linear roller-coaster ride is the only way of authoring a "sandbox". A smarter way, in my opinion, is for instance the ringing phones in public phone booths in Grand Theft Auto 3. When you hear a phone ring, you can go and pick it up and the voice on the other side will give you a mission. These missions are entirely optional, but they do allow you to get more familiar with elements of the virtual world that you would otherwise not have access to.
about the "narrative environments" you have in mind, why couldn't we call them "sandboxes"?
Because a sandbox is not necessarily authored. You could throw a bunch of random elements together and then tell the player "Play! Be free!" But I don't think this is very interesting. Authorship starts with the selection of the elements in your sandbox, how they trigger meaning on their own, by their juxtaposition and through interaction with each other and with the player. A narrative environment is a carefully constructed scene intended to generate meaning. Not necessarily one specific meaning. Ideally meaning should arise out of the combination of player and game. But this is not "open". And it is not about only the "player's story". The author should consider their player and give them things that they can fantasize about. A little bit of psychological and emotional manipulation is definitely appropriate.
The archetype of a "narrative environment" for me is a traditional catholic cathedral. These are places that are filled with paintings and sculptures and ornaments that all refer to different parts of the stories that underlie the religion. Depending on the visitor's knowledge of the Bible, they will recognize elements or not. But many of the decorations and elements are not explained in the Bible. To really know what they mean, you often need thorough historic knowledge.
But what's interesting to me is not to discover what things
really mean. When you enter a nice cathedral, you are overwhelmed with the sensation of richness of narrative. And as you look around, you can't help but feel things and imagine things. And since everything in the place was created from the same conviction, from the same passion (even if it wasn't created by the same person), there is a strong sense of coherence, even if you don't literally understand everything. In the end, you
feel the story instead of hearing it, you become embedded in it, you feel connected to it. Those gothic and baroque church designers really knew a thing or two about designing immersive environments!