Sponsored By

Featured Blog | This community-written post highlights the best of what the game industry has to offer. Read more like it on the Game Developer Blogs.

True Non-Linearity in Games

In my first blog post, I present my thoughts about non-linearity in games (especially RPGs) and what defines the cornerstones of a non-linear game.

Dolgion Chuluunbaatar, Blogger

January 20, 2010

14 Min Read


There is a lot of debate about non-linearity and linearity and about how these are conceived

as inherently good or bad. As in another blog post stated, non-linearity is often

misunderstood as free-exploration. Well, what is the real meaning of non-linearity then?

 

 

First, let's look at a definition of the term linear, taken from a Random House Dictionary based online dictionary: 

 

- of or pertaining to the characteristics of a work of art in which forms and rhythms are defined chiefly in terms of line.

 

- involving measurement in one dimension only


So a really linear game does not at any point allow the player to alter the gameflow, which 

would mean that player input is entirely meaningless relative to the story line.

An entirely linear game would thus be not a game, but a movie with mock-interactivity.

I have no actual problem with linearity in games, as long as the stories told and the narrative are really compelling. 

 

Let's take a look at two linear games: 


Metal Gear Solid

 

Metal Gear Solid on the PlayStation would be one example. I've played that game 8 times in

a row, just because I loved the story and its complexity, which required me multiple

playthroughs to really understand. Remember that it is important to make a distinction

between linearity in story line and gameplay. MGS has beautifully non-linear gameplay, but

that is not what I'm focusing on here. 


Final Fantasy

 

The Final Fantasy games are another example. They are in essence very linear games, even

though you can explore a vast world. I have never seen an alternate story line to the main

story in a FF game, thus not counting optional quests such as chocobo breeding in FF7, for 

example. FF gameplay is basically running through triggers that are spread all over a world

map, with occasional sequences of non-free exploration.

 

 

So if the core definition of linear games is that they do not allow the player to alter the main

story line, non-linear games should allow exactly that.

 

 

Let's take a look at two games that are widely considered non-linear:


 

Oblivion

 

I have to admit I did not play Oblivion to the 'end', in fact, I have never even closed a single

oblivion gate. I played through the mages guild quests, the Dark Brotherhood quests and a

few others. It's admirable that Bethesda created such a huge world with so much detail for

my grinding and exploration pleasure. Yes, that's what Oblivion at its core. It has great

gameplay and atmosphere, but virtually null compelling story. This doesn't bother me and I'm

sure Bethesda does not envision Oblivion as a very story driven game (or the entire Elder

Scrolls series).


Fallout 1 and 2

 

The first two Fallout games are games where I really felt the magic of non-linearity. Much like

Oblivion, Fallout has a vast world in which you can travel anywhere, from the moment that

you are out of your vault/tribe settlement. Fallout has an engenious design at its core. 

The story is what you play it to be. Especially the first Fallout surprised me when at one point

I stumbled upon this ghoul city, killed the entire population for fun and found the waterchip. 

There is to my knowledge no trigger that gets activated after a certain quest or anything like

that. Fallout is much more 'realistic', or closer to what a scenario like this would be in real life.

You have one mission, and a huge world,  but you don't have to follow some chain of events

squishing you into some narrative or plot line because some designer wants you to. 

Of course you can follow a plot line, a series of quests (in which you have a lot of decision

opportunities that can alter the layout of the world somewhat), but since this isn't

neccessary to finish the game, it makes all the quests secondary, and therefore feel like it is

really your story. 

 

 

I have taken RPGs as an example because I feel that RPGs are the best suited genre for

non-linear story telling. Some people might even say it is the core premise of an RPG to allow

the player total freedom of choice and action to live the character he/she is playing. But what

is the most non-linear RPG? 


Real Life.

 

Yes, this is philosophically debatable; there might be no such thing as free will, but I like to

believe that there is, and that there are infinitely many parallel universes and realities etc. 

But since games allow us to restart a virtual 'life', change our decisions and save/load to

experiment with the consequences, games can indeed create an experience of free will in a

life like environment. So in order to create a 'truly' non-linear game, we have to see at what

makes our real life non-linear.  


In real life we are not the heroes of the world, yet we are the heroes of our own story.  

 

In real life, other people have their own agendas, and are just as much protagonists in

relation to the general world as we are. 

 

In real life, we can affect the physical world, but also the world of other people.

 

In real life, we can (though it is very hard), affect the general world and so make an impact

on the lives of all other people.

 

Our own story is simply the result of our actions towards other people, and the resulting

consequences, which we often cannot anticipate, since other people also have a free will

and an agenda. Outer influences such as natural catastrophies can also influence our story/world. 


So I am wondering, is it possible to create an RPG that features these concepts? And what

would we have to change in games of today to implement them?  

This is held in very high level, since I do not know much about the technical side of

implementing those features (I'm a 3rd year computer science student).

 

Firstly, RPGs need to improve on NPC AI and their daily routine. In fact, it shouldn't be 

routine, but a logical following of their agendas which can change due to circumstances. 

For example, you'd have a very simple NPC who works at a shop from 8am to 8pm, goes

home, stays together with his family etc. The NPC simulation system could be designed

around needs like in The Sims, which I think is the best NPC AI there is nowadays. 

Then, there would be a mafia or street gang kind of organization that regularily picks up

protection money from the shop keeper, which he earns from other NPCs who live in the

area that buy things from his shop regularily. You as a player can influence this system in

many ways. You could destroy the mafia entirely, and leave the shopkeeper to random

robberies, but also his wealth could increase, as well as his happiness, and this would earn

you more respect from him and the people who are aquainted with him (customers in the

area), which could maybe be of help in quests (yes I still envision handmade quests).  

Or you could kill the shopkeeper and the mafia would be after you, and sooner or later a

new shop will open, or the customers will go to other shops farther away to buy the

products they need. You could also kill the customers, thus destroy the shopkeepers

customer base and thus make him unable to pay protection money, which will lead the

mafiosi to destroy his shop, and cause him and his family become homeless.

 

I deliberately use killing off people in these examples as a means of creating an impact on

the NPC worlds because this is the most consquenctial of actions one can do. People often

grade RPGs with non-linearity in terms of how possible it is to kill off NPCs and if it breaks the

game.

 

Killing off people is also very easy to implement from a technical side. Most other forms of

interaction, real free dialog for example, are much harder to implement, if not impossible with

todays techniques. So far this sounds like a very complicated sandbox, simply a more

advanced Oblivion. 

 

 

How can we create compelling narrative out of non-linearity?

 

What makes a story compelling? I would say it's the characters, and the believability of their

actions. Characters that we can identify with can allow the player to create an emotional

connection with the character, thus becoming compelled with the story line. This is done

wonderfully in the Final Fantasy games, for example.

 

I believe NPCs and their personalities should be designed by hand, as a means of indirectly

influencing the narrative experience of the player. In Gothic 1, or maybe 2, there was an

obviously handmade character with a unique AI. He would follow you around, anywhere, and

he was good at it. In the middle of combat he would start a conversation, freezing the action

and ruin your gameplay experience. So I killed him after I had enough since I didn't find a

way to get rid of him otherwise. It felt bad, but I have to admit it felt satisfying. But the main

accomplishment of this NPC is that I felt something at all. I do not have an answer how to

implement real dialog, and I know this is one of the most challenging problems of game

design.

How can we communicate our personalities towards NPCs and get meaningful reactions, that

are not premade and thus limited? Multiple-choice dialogs and dialog trees are not

non-linear. Simply no dialog and instead bars like in The Sims is not immersive.

 

I have been thinking about this issue a lot, and can't seem to come up with a good answer.

The most logical solution would be a full blown parsing AI that can have real conversations,

but that is unrealistic at best.

 

For example, as in Emily Short's analysis ("Communicating Character in Fable 2) about

Fable 2, how could the player communicate his/her previous experience as a means to give

solace? This is exactly the point where game narrative is stuck and unable to create an

emotional connection as movies or books can. Sharing your own previous experience in life

to connect with another person is one of the common things people would do. It's in our

psychology, and since psychologically people are more predictable than we like to admit, I

think a state machine would be a good option. This state machine would keep track of all

previous interaction, our previous experience, the state of the world (Shopkeeper 123: dead.

Reason: killed by robber, etc) and from this status quo figure out by common psychological

"algorithms" sensible options for the player. 

 

This would be in the scenario of Fable 2: The man who had a crush on the player is dead,

killed in action. He was not or could not (this is tricky to interpret) be saved by the player.

The player either feels remorse, or relieve or nothing or a number of other things. Then the

player meets a woman who just lost her husband and is in a state of emotional shock (using

a Sims like AI system). This relates to the player's own previous experience and thus the

player would be given options (some dynamically determined) to:

 

1. Tell about his/her own experience and solace the NPC

2. Pour salt into her wound and make fun of her

3. Tell her to get over herself

 

These dialog options are pre-made, and therefore limiting. The state machine has an arsenal

of very general dialog options such as the second and third above, but also more context

sensitive like the first one. NPCs would also have a similar arsenal of dialog options next to

their unique dialog texts given by the designer. 

 

Some of the dialog options as you can see could be dynamically inserted taking into account

what the state machine knows about what happened before. This is obviously a hindrance

to non-linearity, but at least partially dynamic. After a while of playing, through our actions

and choices in dialog, the game would also have a better idea of what kind of personality we

play. This would have an impact on our reputation etc as you have already seen in other

games. 


What is also important is that the world functions by itself much like a simulation, that means

that people are dependant on each other, and their services to the community. This can be

derived from city building games such as SimCity, Anno or Caesar 3. Then we could add in a

villain, the clichee dark wizard who creates an army to overrun the lands. This villain would

also have a logical system of underlings that functions to produce more underlings. There

would be an AI for the evil wizard to strategically overtake the lands, and on the other side a

good king also planning a strategy. Regardless of the players actions, this war will take

place, but you as a player can participate, and influence the outcome of battles. Playing an

assassin character you could for example assassinate the orc general at night right before a

battle and thus make it easy for the humans to defeat a mindless group of orcs. You could

even try to kill the dark wizard in his sleep when you are still at level 1, which would be

incredibly hard, but not impossible in theory. There should be no limitations, your amount of

influence should only by limited by your skills alone. 


In conclusion, a truly non-linear story lined game (taking RPGs as the focus), requires a

systematic world that works by itself, feeds from itself, and the player only being a part of it,

allowing the player to express him/herself in this confined environment. The hardest element

from a design point is communication between you the player (not the actual character) and

NPCs, which is not able to capture non-linearity (yet). A vast world is nice, but not a

requirement for non-linearity, as the essence of non-linearity is not in freedom of exploration

but in freedom of experimentation within a defined system. 


Please comment with constructive criticism.

Read more about:

Featured Blogs
Daily news, dev blogs, and stories from Game Developer straight to your inbox

You May Also Like