[MMO] Named items - a mechanism for a consensus reality.

I've been wondering how I could intuitively make it so that some things would only be real to one player, and other things would be globally, part of the "consensus reality".

I've come up with the idea of "Cosmetic items", "Named items" and "Hero items". This should be intuitive to anyone who's ever watched a movie or read a book. If you give something a name, it's important to the plot. Cosmetic stuff doesn't matter at all. And the hero, he's critical to the plot.

PROPERTIES

While objects may have many properties (how damaged they are, what they are made of, who owns them, etc) there are a few properties that the server will care about for every item. These properties do not have to be fixed: an jewel could become Gettable, for example, once you levered it from the idol's eye socket.

1. Static - Static items are for boulders, trees, and buildings. Anything that cannot be moved or changed or damaged, should be a Static item. Knowing that something won't be moving lets us optimise all sorts of things, like the lighting, collision detection, and so on. Static things can't be Destroyable or Gettable.
2. Gettable - Gettable items can be placed in inventories, and given to people, and traded. They may have a value. They can't be Static.
3. Destroyable - Destroyable items are things that the user can bash into powder, eat, flush down a drain, or otherwise remove from the world. They can't be Static.
4. Physicsable - Physicsable items are those subject to physics. Bouncing, rolling, falling, flapping, sliding, being thrown, floating, or having things bounce off them, etc. While all Scriptable items can have physics faked with a script, only Physicsable items are optimised to do it really fast with no scripting. All Static objects are Physicsable. Hero items can't be Physicsable.
5. Scriptable - All items can have clientside scripts and behaviours attached. Scriptable items are those which can have serverside ones, too. These scripts can include the command "let everyone nearby know this script was run". So you can have an Named door with a serverside script to open it, that lets everyone know you did so, so they'll see the door opening too.
6. Per-player - Sometimes, you need an item that everyone can get one of. Keys for quests are a good example. If you only have one key for a door, then if someone takes the key and hides it, the quest is no longer completable. If every player who "picks up" the key just gets a copy of it instead of the real thing, then the problem's sorted. These can be either Named or Hero items, but are special in that whatever a player does with them, the details of the action are never sent to any other player.

TYPES

Cosmetic
The server does nothing at all with Cosmetic items, and does not know they exist. Cosmetic items can't be Static, Gettable or scripted. They can be Physicsable and Destroyable. They are always created and destroyed by the client, which doesn't tell the server anything about them.

Cosmetics are for sparkles, ripples in water, puffs of steam, and stuff that other people might never see, or will see their own version of. If you have a dripping pipe, making a Named pipe with a clientside script to create Cosmetic drips would be best. Cosmetics cannot be placed in your inventory. Cosmetics will not be there if you walk away and come back - neither your client nor the server will remember they ever existed.

1. If your friend opens a Cosmetic chest, you won't see him do so: the opening only happens on his computer.
2. If he sits in the open chest, you will see him sit, ghostlike, inside the solid chest.
3. If he pushes it across the floor, then you will see him do so, since it is affected by physics on everyone's machine.
4. If either of you leave and come back, then to the person who left, the chest will not be there.
5. He cannot pick the chest up.
6. If he smashes it, then his computer will decide whether he manages it, but any results will be shown only to him.

Named
The server does very little with Named items, caring only if they are created, destroyed, or added to/removed from an inventory (which it treats the same as destroy/create). Everything else is left to the client. The server does not keep track of where the items actually are in the world. Named items can be Static, Gettable, and/or scripted. They are always Physicsable. They may be created or destroyed by the server, which would then tell all local clients; or by the client, which which would then tell the server, which would then pass the message on to other local clients.

Named items are for sandwiches and pebbles, cutlery and clutter, houses and hedges. Most stuff in the world should be Named, particularly Static things. As they are subject to physics, they are the most "believable" objects, however, this means they can become "desynched", so they are the things that either do not move, or, while you want other to people see them, you don't mind whether they all see them in the same place or state.

Any unimportant Gettable item is a candidate for a Named item. Named items aren't "worth" anything, since the server doesn't store them, they're entirely clientside. The server will let anyone in the area know when you take one out of your inventory - but because they aren't stored serverside, it won't check that it was in your inventory in the first place! It will also believe you when you put them into your inventory, rather than checking to see if you're close enough and strong enough and all that jazz. It will check the item is Gettable, though, so no popping houses into your bag.

Anything Destroyable is a candidate for a Named item. Again, the server will believe you when you say you destroyed it, if it's a Destroyable item.

Anything Physicsable is a candidate for a Named item. Cloth and liquids must either be Named or Cosmetic, because these rely on clientside physics.

1. If your friend opens a Named chest, you won't see him do so (just like Cosmetics), unless "opening" is a server-scripted action with a line saying "let everyone know".
2. If he sits in the open chest, you will see him sit, ghostlike, inside the solid chest.
3. If he pushes it across the floor, then you will see him do so, since it is affected by physics on everyone's machine.
4. If either of you leave and come back, then the chest will still be there when you return, but in the original spot, rather than where he pushed it to.
5. If he picks it up, then it will be gone into his inventory, even if you go away and come back.
6. If he smashes it, then his computer will decide whether he manages it, and if so, it tells the server, the server believes him, and the server tells everyone in the area that it has been destroyed.

Hero
The server carefully tracks the position and state of Hero items. No Hero item may be moved without the server giving permission, and the server may move them at any time. Hero items can be Static, Gettable, scripted and/or Destroyable. They are never Physicsable, nor Static. They may only be created or destroyed by the server, which then tells all local clients that the item exists.

Hero items are for movable things like players, NPCs, monsters, important doors that you don't want people to cheat past, and important keys that you don't want people to make two of. They are the "consensus reality", in that anything that happens to them happens on everyone's machine, but you are limited with what you can do with them. They are not Physicsable, so they are not as "believable" - any physics behaviour needs to be added on with a script. Because they are expensive in terms of server load, you should keep Hero items to a minimum.

Any important Gettable item is a candidate for a Hero item. Hero can have a value, since the server stores and manages them, and can prevent cheating. The server will let anyone in the area know when you take one out of your inventory, but will check that you have it in your inventory first. It will also check whether the item type is Gettable and you're close enough and strong enough and have enough inventory space etc before letting you pick one up.

1. If your friend opens a Hero chest, you would see him do so.
2. If he sits in the open chest, you will see him sit, inside the open chest.
3. If he tries to push it across the floor, he will be unable to, unless this action has been scripted into it,
4. since it is unaffected by physics.
5. If either of you leave and come back, then the chest will still be there when you return, in the state you left it in.
6. If he tries to pick it up, the server will check whether he can, and if so, it will be gone into his inventory.
7. If he smashes it, then the server will decide whether he manages it, and if so, tell everyone in the area that it has been destroyed.

NAME SYNTAX

Not sure what to use for names. Here're some thoughts though.

On the cover of the book it could be anything the artist wanted, with their name automatically appended, like "Little Red Riding Hood - Dewi Morgan". But that'd get a bit lengthy so internally, if I've done ten stories, then the story I'm working on now could be called "DewiMorgan_11".

All named and Hero items would also need a unique name. First, there'd be the name that the programmer used, which would only need to be unique within their own story. So:
NPC_Wolf
MainDoorToCastle
MagicRock

If there are multiple clones of an item, then:
NPC_Wolf(1)
...
NPC_Wolf(312)

Then, the "canonical" name, unique to every item on the server, which is just the storyname tacked onto the front, like:
DewiMorgan_11.NPC_Wolf(42)
DewiMorgan_11.MainDoorToCastle
DewiMorgan_11.MagicRock

Of course, the server will internally most likely just use a number.

STORY CONFLICTS

If you had a Hero item in a story, this would cause problems in various ways:
1) You could write a story about having a million dollars (money's a Hero item, it has value), and then become rich just by reading your story.
2) If someone had a Hero item in a story, the server would have to know not to send messages about it to other people, because they couldn't see it.
3) If someone had a Hero item in a story, another Hero item could hit it and bounce in one direction... while also NOT hitting it in everyone else's reality. The server would then need to track multiple realities, which is not possible.

So, stories can ONLY use Cosmetic and Named items, and scripts attached to Named items in stories cannot affect Hero items.
However, non-Physicsable Named items can be marked to become Hero items if the story becomes "canon" through the voting process described elsewhere.