Tuesday, 20 June 2017

Gaps of the Imagination

We don't perceive every single piece of information around us. Instead we must constantly fill in blanks in our knowledge to properly create a mental image of the world. This processes of filling in gaps is really important to understand and to exploit when crafting games.

At the very core, games are driven by systems. We have extremely powerful machines that can quite accurately simulate various forms of physics, economics, group dynamics, intelligence and so on. This means that at our fingertips are the tools to create entire worlds. It is therefore very tempting to use these in order to solve every single problem. But this is not always the best approach. Sometimes it's best to just leave gaps, and let the player's imagination handle the rest.

There are five core reasons why this is so:

  • We are all unique individuals with different needs and likes. By leaving things unsaid, players can personalize their experience without any asset requirements from the creator. A typical example is that players can envision the sort of monster they personally are the most afraid of.
  • It is impossible to simulate things on an atomic level; there always needs to be a cut-off at some level. Since highly complicated things tend be unstable and encourage scrutiny, it is often better to make the cut off at a higher level.
  • There are certain things which are, for various reason, not possible to implement properly. In this case a lot can be gained by simply leaving it to the imagination. This includes everything from creating immense battle scenes to conveying a particular emotional state.
  • For the sake of pacing; sometimes it's simply not possible to give the player all of the required information and it's better for them to just work it out for themselves. This could be things such as background story, details on a map, or the areas that it's possible to visit in a location.
  • There is an inherent enjoyment in filling out blanks in various forms of art. The reasons are a bit fuzzy, but you can clearly see it in all art. It's fun to wonder what a character is really feeling, what events lead to a scene, and to mentally picture what a shadow is hinting at.
All of this works because of how our brains is constructed. We are all equipped with highly capable pattern-matching machines. Our brains, and therefore we ourselves, want the world to make sense and will always try and fit things into a coherent and convincing narrative. The simplest example of this at work is motion.  Just consider this animation:

This is really just a series of circles that we see in rapid succession. Despite the fact that it's quite easy to notice the individual frames, we still see it as a ball jumping up and down. We fill in the gaps between the frames and see it all as an animation. Notice that this doesn't really take any conscious effort - it comes naturally. In fact, it is quite hard (possibly impossible) to not see this motion. When done right, gaps of the imagination never really feel like such - they simply get incorporated into the overall experience.

Here is another classic example:


There is no white triangle pointing downwards, but the other shapes suggest that there should be, and hence we see one. Again, this is something that we carry out automatically and while we can rationally understand that there really is no triangle, we cannot mentally unsee it.

Closing gaps like this is not just a fun side effect. It is a crucial way in which our brains function. Taking decisions on incomplete information is an essential skill in the function of our day to day lives. In fact, most of the information we receive is incomplete - it's quite rare that we are directly exposed to situations where we have all possible information to hand. So it's not so strange that closing gaps should come so naturally to us, we literally wouldn't be able to survive otherwise.

As I have said before, any decisions we make are based around a mental model. In our heads is a mental simulation of how we think the world works, and before we do anything we first run through the action in our model to see if it would have the effect we intend. However, it is not possible to get complete information about our surroundings. So in order to get a working map of the terrain we need to fill some of the information. That is what the gaps in imagination are all about - our process of crafting a working mental model.

Given that this is a foundational part of how people work, it is essential that we always have it in mind when designing games. After all, the end result of a game is really to create a specific mental model in the player. This can be done through direct system access, sensory input or, what this post is all about, through suggestions of something unseen.  I will now go over the most common, and most important, ways in which gaps can be used.

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Sensory Gap
This is the most common one and also easiest to understand. When we are presented with sensory information that is somehow incomplete, we try and fit it into a working context. There are many different ways in which to do this. It can be quick, disjointed shots of something, events seen through the eyes of a monster, a character reacting to a smell. or a sound that is so loud it shatters glass. Normally you build this sort of gap up by presenting a negative space where one or more object/events/reactions/etc. all related to something unseen. 

We tend to use this sort of gap more than we realise, simply because it is such an ingrained way of working with various artforms. But that just means you have to be extra aware of how it works. For instance, it's good to know that we are extremely prone to seeing familiar shapes, such as faces, in just about anything. 

It's actually quite hard to not see anything in an image. We have evolved in an environment where there was nothing like pure noise, everything we saw was part of the environment somehow. Therefore, when we see random patterns the brain goes into overdrive to find a connection. Of course, it is not just the direct information received that we use to do this, but anything related is accessed as well. Because of this, you can often get away with very little if the scene is just set up in the right manner. Learning to do this is incredibly important.


Informational Gap
This is very similar to the sensory gap, but instead of sensory data it deals with information in the abstract. Jeff Vogel recently wrote a blog post on how games often have too many words [1], and properly using gaps is the best remedy for that. It is often easy to underestimate just how much information a player is prepared to fill out for themselves. You might think that a player really needs to know details of everyday routines in order to fully understand how a certain society functions. But often it is just as good to simply have some brief glimpses (visually or through text) of what they are doing along with something that sets the tone (music, animation, etc). 

This sort of advice might seem a bit obvious, but it is worth keeping in mind how good we humans are at filling out these sort of gaps in information, especially if it comes in form of gossip. Gossip is something that has probably been part of our lives since before we evolved into modern humans. We are social animals and gossip serves as a tool to keep track of the group we are living in. This means our brains are extra-sensitive to this sort of information, similar to seeing shapes and motion, and can easily assess even the smallest hints.


Spatial Gap
Games are often very spatial and requires the player to navigate various places. Because of this it is often very tempting to accurately represent every single area to give a proper sense of place. However, for various reasons this might not be feasible or required. It is then important to note that spaces can also be created from gaps, just as much as sensory information and lore. Spatial gaps are a bit trickier though as we are now messing with the actual play area which means you you have to be extra careful.

The sloppy way to implement is to simply have a lot of locked doors that the player cannot access. But this can be bad for pacing and, worse, it can lead to a weak mental model. The brain is usually quite lazy and will try to optimize. If the pattern becomes 'locked door equals the room is irrelevant', it will be noticed and incorporated into the model. After all, dismissing these spaces is much easier than assuming they are there.

Instead it is better to vary the ways in which the rooms are blocked off, and to build up a negative space hinting that it is there, such as glimpses into it from a small window. It is especially effective to make the player believe that room might contain something of value. That way it is much more likely it will be part of the mental model. Remember, what matters is not what is actually there, but what the player perceives to be there.


Causal Gap
This next time is very similar to the animation example from above, but happens over longer time scales. As I said before, closing gaps is all about creating a working mental model. Where the previous gaps where are all about what we see, causal gaps is more about why we see it. Just like we humans are quick to see familiar objects in random patterns, so are we quick to correlate two events with one another. A black cat runs over the street and then you get a headache. We humans often correlate the most strange occurrences and it is quite hard not to. Many of our psychological fallacies are really based around this fact, and it takes effort to learn not to do this. Why is this so? Because for our ancestors it was okay to have a few weird beliefs if it meant we could pick up on dangerous situations and survive better. If you are a skeptic about the cat causing the headache, you might also be skeptical towards the signals of an impending avalanche. 

This is obviously the sort of brain glitch that we can make use of in art. Film is a medium that uses it all the time, in editing. See a gun fire, and then a person being hit, and it is obvious what has happened. Correlating these two events into a single event comes naturally to us. But because games are so driven by the player understanding the flow of input and output, or how the player's actions correlate to events in the game world, it gets a bit harder to deal with gaps.

The simplest way to do it is with events taking place. For instance, say the player suddenly notices that a door is blocked, and hears the sound of feet running away. They will now assume that whoever is running away is also the one who blocked the door. 

A little harder is for us to provoke imagined causal connections from actual interaction. What I mean by this is that you actually leave out certain information when actions take place, and ask the player to fill in the middle. For instance, if I click on an object in a game and it simply pops into my inventory we would like the player to mentally simulate this as "I picked up the item" and not "the item got magically teleported into my inventory". The three key elements for achieving this are consistency, negative space and optimization-avoidance.

Consistency means that we need it to happen in a way that makes it possible to distil it into a couple of universal rules. For instance, is the distance you can pick up items at consistent with the player using their hands? Negative space means that we use other events to reinforce the fantasy. These can be sounds effects when you pick up, feedback messages when you are too far away, and cutscenes where we see this happening for real. Finally, optimization-avoidance means that our intended mental model, that of the player actually picking these objects up, must be the "simplest" [2] available explanation. If there are too many edge cases, weird behaviors or simply not enough supportive negative space the "magical teleportation"-theory will win.


Anticipatory Gap
This one is quite similar to causal, but worth having in its own category. These are basically events that might happen to the player in the future and that they will take into account when planning. As explained in an earlier blog, planning is a core reason why gameplay is engaging, and thus it is important to shape what sort of consequences the player can conceive of taking place. When the player plays a game, they will generate their mental models not just based on what they are playing, but also what they know from before. This is gives us an opportunity to make the player think certain things are possible, without them never having witnessed them.

Suppose that the player hears footsteps from afar. These might just be coming from a couple of scripted sound effects, but the player doesn't know that. Given the right context the player will conjure up a monster that is making these sounds and assume that it might attack them. Now the player will start making plans based on a few sound effects and project a lot more onto the game than what is actually there. This is something that we saw a lot in Amnesia. The player could create long, and engaging, gameplay situations for themselves only because of a few sound effects. 

Of course, this sort of trick can't last forever. As I have mentioned several times, the brain likes to optimize and once the pattern gets to clear the illusion will go away. So it is important to constantly update the negative space, to not make the events so predictable and to setup situations in ways that feel exciting to partake in. Even more important is to make sure that this trickery is not the only gameplay there is. If the player has a baseline of actual planning  and execution going on, this sort of illusory anticipation can be sustained for quite a long time and add a lot to the experience.


Agency Gap
If you are in the jungle and the high grass suddenly moves. Do you:
  1. Assume it is a tiger with the intention of eating you?
  2. Be skeptical and consider that it might just be the wind playing tricks?
In our ancient past, the people who thought like number 2 were much less likely to survive. Sure, they escaped the embarrassment of being afraid of grass from time to time. But they also got eaten a lot more by tigers. Thinking of events as being caused by something with agency (e.g. an animal) is powerful concept for survival. It is also something that leads to all sort of weird beliefs like tree spirits and demonic possession. For many events it comes naturally to think of them as caused by intentional beings. And once again, this is great stuff to use in games.

This video that is a great example of the whole thing in action. Just note how you directly project agency on the shapes.


The most common use of this is in enemy AI. Most of the time, AI that feels smart is because the player thinks it is so, not because the underlying systems are complex [3]. F.E.A.R. is a great example of this. While the AI does have some clever systems at play, it derives most of its impressiveness from being good at giving the player feedback. For instance, by saying "cover me" while a grenade is thrown, it gives the impression that much more is happening than what actually occurs. The player projects a set of thoughts running through the soldier's mind and incorporates that into their mental model. But in reality it is just very simple code that is executed.

This is an area where the brain works a lot to our advantage. We are ill-equipped to mentally simulate things like state machines, but it comes naturally to think in terms of people. This means that we can get a lot of content to the player only through suggestion. The player's brain is really apt at simulating people and can do so much better than any existing computer system. So the more of that power we can use, the better.

All of this get harder when we get away from combat though. While players want to think of other characters in games as entities with rich mental lives, there is a limit to how far they are willing to go. If animations start to look weird, if responses come out as canned or if interaction possibilities are too limited the brain gets lazy and optimization kicks in. Characters go from intentional beings to simply being objects.

A big problem of interactive storytelling is how to keep this from happening. Just as I discussed with causal gaps, the key elements in achieving this are consistency, negative space and optimization-avoidance. How exactly to achieve this with characters is still too unclear and complex to cover this time around - I will go over some possible directions in a future blog post.



Volition gaps
Finally we have arrived at the last gap type, which is similar to causal gaps. Previously we have mostly talked about things happening when the the player is the one causing it, but volition gaps contradict that. These are events that the player thinks they cause when in fact they don't.

This is something that I think currently is quite unexplored and has a lot of potential. It is quite hard to construct control interfaces that allows the player to take all the possible actions. Therefore it would be nice if we could have actions that the game does automatically but that the player believes they used their volition to cause. This is what this gap is all about.

Just like we construct a mental model of what is happening on the outside world we are also constructing a narrative of what we are doing ourselves. While we are not conscious about it in everyday life, a lot of the time we have reasons and beliefs because we do certain things, instead of the other way around.

For instance, take choice blindness. In an experiment the subject had to pick which face they thought were the most beautiful, and then when handed back a different picture, most subjects continued to explain why they had chosen it. So a lot of the time, we make up reasons based on the actions we find ourselves doing. And as always, whenever there is a brain deficiency, we should try and exploit it for art.

The best example of this effect in use is in Assassin's Creed. When you run across the roofs in a city, the game will automatically make the character jump. Despite that, it always feels like you are the one who is willing those jumps to happen. This works as a great way of streamlining the controls and making the experience more fluent without taking away a sense of agency in the player. Another example of is in games like Uncharted where the character will interact with the world in ways that make sense and enhance the feeling of being there.

I believe that these sort of gaps can be taken further, though. An interesting example of this is The Path, where the protagonist will carry out actions of their own choice when you leave them alone. It is by no means perfect, and doesn't really provide an illusion of volition. But I think it shows the potential of this and I think causes the player to feel intimately involved with various events if used correctly. Currently, though, it is too unexplored to say for sure what the possibilities really are. I will explore some more thoughts on this in a later blog post.

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That should summarize the basics for the various gap types. I am sure there are even more than these, but this selection is what I found most useful for games. In upcoming blogs I will dig deeper into some aspects of this and give more examples on how it affects gameplay.

Until then I recommend reading Ian Thomas's excellent article on the subject where he discusses gaps for LARPs, SOMA, and much more.



Footnotes:
1) The follow-up post that looks at the game Pillars of Eternity specifically is also well worth reading:
http://jeff-vogel.blogspot.se/2017/06/games-have-too-many-words-case-study.html

2) This is simplest in terms of effort used by the brain, not in a strict theoretical sense. For instance "a witch did it" is a simple explanation for a human brain, but in reality is quite complex because it assumes a lot of attributes for the witch. But we as humans are great at just ignoring this, making the silly explanation seem simple.

3) This video shows it off nicely: https://www.youtube.com/watch?v=9bbhJi0NBkk


Thursday, 15 June 2017

Choices, Consequences and the Ability to Plan

This article goes over why it is so important for choices to matter in a game and how it all has to do with planning. If a user perceives that their actions have no consequences, you remove a core component of engagement - the ability to plan.



Say you are playing a game like The Walking Dead, or any other interactive movie, and you are faced with the choice whether or not to help someone who is hurt. You decide that you want to help the person, after which you never see them again for the rest of the game. Reloading a save and playing through the scenario you find out that if you chose not to help, the same thing plays out. Simply put: in this case, your choice really has no consequences.

While the scenario is made up, it presents a very typical situation that opinions are heavily divided on. Some people are totally okay with it for various reasons. But others will argue that this lack of consequences ruins the entire experience, as your choices doesn't really matter. It's really easy to say that people who feel this way are simply playing the game the wrong way or are not properly immersed. However, I think it's really important to investigate this reaction further as it gets us closer to some fundamental problems of narrative games.

The argument from people who get annoyed by these non-choices goes something like this: if every branch leads back to the same path, then you really don't have any say in how the game plays out. You are not playing a game, you are only pretending that you are. It's like when you are playing a split-screen game and notice you've been watching the wrong side. The feeling of play is just an illusion. Nobody would tolerate a Super Mario where a pre-written script - not the player's skill - determines whether or not they survive a jump, so why tolerate games where all choices lead to the same conclusion?

One could counter that by saying the intention is to put you into a hard position and the game is about your varied emotional reactions as you ponder the different choices. It isn't about affecting how the game plays out - it is about making an emotional journey. If you require the game to show you the consequences of your actions, you are not immersed in the game's story - you are simply trying to optimize a system. This might sometimes be the case, but I also think this line of thinking is missing what the actual problem is: the failure of the player's mental model.

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Let's start by breaking down the problem. A mental model, as explained in this previous post, is how the player perceives the game's world and their role in it. As you are playing a game, you slowly build a mental model of the various objects and systems that make up the game and attach various attributes to them. At first a box might just be a piece of the background, but as you learn you can destroy it in order to gain items, attributes are added. The object gains complexity. The reverse can also happen. For instance, when you first see a character you might think that you are able to speak to it and therefore label it with various attributes you know that humans usually have. But when you find out that the character is really just a piece of the background without any sort of agency, most of those attributes are lost.

Your mental model of a game is something that is continually revised as you are playing, and it is something that always happens, no matter what the game is. In fact, this is a process that is a core part of any medium, including books and films. So, obviously, when you are playing an interactive movie game, you are not simply reacting to a direct stream of information. You are answering questions based on your mental model.

Take my "will you help your hurt companion?" scenario from above. The knowledge you take into account about that choice is not just what is currently projected at you from the TV screen. It is a combination of everything you have gone through up to this point, along with a bunch of personal knowledge and biases. Even basic concepts like "hurt" and "companion" aren't just created in this moment. They are ideas that the game has spent a lot of time building up, be that for good or bad, from the very moment you started playing.

When you are faced with the hypothetical scene of  a hurt companion, you are not just dealing with an animated image on a screen. You are dealing with a whole world constructed in your mind. This is what your choice will be based around. While it might objectively seem that everyone is reacting to the same scenario, they may in fact be dealing with quite different setups.

So when someone gets annoyed by the lack of consequences, it is not necessarily the direct consequences that are missing. The issue is that they have constructed a mental around a real person in need, along with that person's future actions. So when it becomes apparent that the game doesn't simulate that as part of its own model, the player's mental model is broken and it feels like a big let down. Remember that we don't play the game that is on the screen, we the play game as we perceive it in our heads. So when it turns out that your imagined world is fake, it has a huge impact.

It gets even worse once we take into the fact that planning is fundamental to a sense of gameplay. As explained in a previous post, engaging gameplay is largely fueled by the ability to make plans. The way this works is that the player first simulates a course of action using their mental model, and then tries to execute that in the game. This is a continuous process and "planning and executing the plan" is basically the same as playing. Interactive movies normally don't have a lot of gameplay and it is really only in the choice moments that the player gets to take part in any actual play. Hence, when the choices turn out to have no consequences, it becomes clear that planning is impossible. In turn, this means that any meaningful play is impossible and the experience feels fundamentally broken.

As an example, take this experience I had with Heavy Rain:
[...] one scene I had made a plan of actions: to first bandage an unconscious person and then to poke around in his stuff. There really was nothing hindering me from doing so but instead the game removed my ability to interact directly after caring for the person. The game interpreted me wanting to help the guy as I also did not want to poke around, thinking that they two were mutually exclusive actions. Of course I thought otherwise and considered it no problem at all to do some poking afterward.
I think that people to complain the loudest about the lack of consequences are extra sensitive to situations like this. But, as I said, this is not due to lack of consequences per se, but due to the impact it has on the consistency of their mental model and sense of play. It is really important to note that this is not due to some sort of lack in immersion or ability to roleplay. On the contrary, as I have described above, many of the issues arise because they mentally simulate the game's world and characters very vividly.


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So the problem that we are faced with is really not a lack of consequences. It is because the underlying systems of the game are not able to simulate the mental model for a subset of players. One way of mending this is of course to add more consequences, but that is not a sustainable solution. Additional branches increase exponentially, and it quickly becomes impossible to cover every single possible outcome. Instead it is much better to focus on crafting more robust mental models. Sure, this might entail adding consequences to choices, but that is just a possible solution - it is not the end goal.

As I outlined in the previous blog on the SSM framework it is incredibly important to keep track of how systems and story help form a mental model in the player's mind. For instance, if you start your game saying "your actions will have consequences", that will immediately start filling up your player's imagination with all sort of ideas and concepts. Even how pre-release PR is presented can affect this. All of these then become things that lay groundwork for how the game is modeled in the player's head and it is vitally important to make sure this mental model remains stable over the course of the game.

One of the main things to have in mind is consistency. Remember that as someone is playing a game, they are building up a mental simulation for how things are supposed to work. If you provide information that certain events are possible when they are in fact not, you are running the risk of breaking the player's mental model. You either need to remove this sort of information or to make sure that they never take part in situations where these sort of events feel like a valid option.

However, the most important thing to keep in mind is the ability to plan. A major reason why the lack of consequences can feel so bad is because these consequences were part of the player's gameplay plans. So when it becomes apparent that they don't exist, the whole concept of play breaks down. In all fairness, this might be OK for certain genres. If the goal is to simply to make an interactive movie, then losing a subset of player might be fair. But if the goal is to make proper interactive storytelling, then this is of paramount importance - planning must be part of the core experience.

That doesn't mean that every choice is something the player needs to base their plans on. But in that case then there need to be other things that lie on a similar time scale and which are possible to predict and incorporate into plans. I think that one way around this problem is to have a more system-focused feature that runs alongside the more fuzzy narrative choices. When the players make choices, their mental model will have the best predictive skills around this more abstract system, and play revolves mostly around this. Then when more narrative choices are presented they will feel more game-like and part of the a solid simulation, despite not really having any consequences.

A simple and good example is the choices you have to make in Papers, Please. This game is driven by a type of survival simulation where you need to gain credits (though doing proper passport check) in order to keep your family live. Entwined into this are choices about who you will allow into the country. Many of these don't have any far reaching consequences, but that that doesn't really matter because your ability to plan is still satisfied. But despite that, these choices still feel interesting and can have an emotional effect.

 This sort of approach relies on combining several elements in order to produce the feeling of something that might not actually be there. This is something that is used in a wide range of applications, from how we view images on a TV, to how films can create drama through cuts. We don't always have to have solve problems straight on, but often the best way is to split the problem into many and to solve each problem on its own. The combined effect will then seem like a solution to the original problem. This is a technique that is super important for not just this, but many other narrative problems. I will write a blog post later on that goes into more details.

Once you have a game that is consistent and that has some sort of planning apart from the more narrative choices, the probability of satisfying the people will be greatly improved. And not only that, your narrative experience will improve over all, for all players, not just a subset. In this case I think it is fair to view these extra sensitive people as canaries in a cave, something that is first to react on a much bigger issue.

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This blog post by no means presents the solution to end all problems with choices and consequences. But hopefully it will give a new way of thinking about the problem and some basic directions for finding a solution. I don't think we will ever find a perfect way of dealing with choices, but the better informed we are at underlying causes, the better experiences we can provide.




Tuesday, 30 May 2017

Planning - The Core Reason Why Gameplay Feels Good

In this post I dig into planning, and how it is a fundamental part of what makes a game engaging. Planning affects many aspects of what is so special about games and why we enjoy playing them. This post will go over the reasons behind this, and explains why planning is so important for narrative games.

I think we can all agree that there is a difference in how certain games feel to play. There are just certain games that feel "gamier" than others. Just compare playing Super Mario to something like Dear Esther, and I think it's clear that the former feels like it has more gameplay than the latter. What is it that causes this? My hypothesis: the ability to plan.

The more a player can plan ahead in a game, the more engaging that game will feel to play.

Before I cover some evidence of why this is most likely true, I will need to get into some background information. In order to understand why planning has such a prominent role in games, we need to look into the evolution of our species and answer this question: why are fish so stupid?

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This is how the world looks to the average fish:


They can really only see 1-2 meters in front of them and often it's even worse than that. This means that a fish can't do much planning. It just reacts to whatever pops up in front of its face; that's really what their lives are all about. If a fish's life was a game, it would be a limited version of Guitar Hero played to random noise. This is why fishing works. Fish don't think like us, they're mainly just driven by hardwired responses.

For a large part of earth's history this was what life was like for organisms. But then 400 million or so years ago something happened. Fish started to move on to land. Suddenly, the view looked more like this:


This changed their world. Suddenly it was possible to plan ahead and to properly think about your environment. Previously, smart brains had been a waste of energy, but now it was a great asset. In fact, so important was this shift that it is probably a big factor in how consciousness evolved.  Malcolm MacIver, who as far as I can tell originated this theory, writes about it like this:
"But then, about 350 million years ago in the Devonian Period, animals like Tiktaalik started making their first tentative forays onto land. From a perceptual point of view, it was a whole new world. You can see things, roughly speaking, 10,000 times better. So, just by the simple act of poking their eyes out of the water, our ancestors went from the mala vista of a fog to a buena vista of a clear day, where they could survey things out for quite a considerable distance. 
This puts the first such members of the “buena vista sensing club” into a very interesting position, from an evolutionary perspective. Think of the first animal that gains whatever mutation it might take to disconnect sensory input from motor output (before this point, their rapid linkage was necessary because of the need for reactivity to avoid becoming lunch). At this point, they can potentially survey multiple possible futures and pick the one most likely to lead to success. For example, rather than go straight for the gazelle and risk disclosing your position too soon, you may choose to stalk slowly along a line of bushes (wary that your future dinner is also seeing 10,000 times better than its watery ancestors) until you are much closer."
 To showcase the above, he has the following image:


This images nicely shows the conceptual difference in the processes involved. In one you basically just use a linear process and "react as you go". In the other one you scout the terrain ahead, consider various approaches and then pick one that seems, given the available data, to be the best one. 

It is not exactly the same, but there is a striking likeness to the following image comparing old school and more modern FPS design:

I know that this is not a completely fair comparison, but the important point here is that when we look at these two images, it feels pretty clear which of these two designs ought to have the best gameplay. The image on the left represents a more complex and interesting landscape, while the one on the right represent a linear sequence of events. And just like the worlds of a fish compared to that of the world of land animals, this means a huge difference in our ability to plan.

There are other interesting connections with the ability to see far and to plan. Malcolm MacIver replies to a question regarding the intelligence of octopi:
"It’s incredible what being an unprotected blob of delicious protein will get you after eons of severe predation stress. They, by the way, have the largest eyes known (basketball size in the biggest deep sea species). Apparently, they use these to detect the very distant silhouettes of whales, their biggest threats, against the light of the surface. 
The theory is committed to the idea that the advantage of planning will be proportional to the margin of where you sense relative to where you move in your reaction time. It then identifies one period in our evolutionary past when there was a massive change in this relationship, and suggests this might have been key to the development of this capacity. It’s interesting that octopuses and archerfish tend to be still before executing their actions. This maximally leverages their relatively small sensoria. There may be other ways, in other words, for animals trapped in the fog of water to get a big enough sensorium relative to where they are moving to help with planning."
Sight is of course not the only reason for us humans to have evolved our current level of intelligence and consciousness. Other important factors are our upright pose and our versatile hands. Standing up meant that we could see further and allowed us to use our hands more easily. Our hands are the main means with which we shape the world around us. They allowed us to craft tools, and in various ways to change parts of the environment to optimize our survival. All of these things are deeply connected to the ability to plan. Once we learned how to reshape the world around us, our options opened up and the complexity of our plans increased immensely. 

It doesn't stop there. Planning is also a crucial part of our social life. Theory of mind, our ability to simulate other people, is both a reason for and a product of our planning abilities. Navigating our social groups has always been a careful activity of thinking about various paths of action and their consequences. 

Planning also underlies two other phenomena that have been discussed recently on this blog: Mental Models and Presence. The reason why we have mental models is so that we can evaluate actions before we make them, which obviously is crucial to planning. Presence is a phenomenon that comes from us incorporating ourselves into our plans. We don't just want to model what happens to the world, but also to ourselves.

So, to sum things up: there are lots of evolutionary reasons why planning would be a fundamental part of what makes us human. It's a big part of who we are, and when we are able to make use of these abilities we are bound to find that engaging. 

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So this background is all very well, but is there really any good evidence that this is actually a thing in games? Yes - in fact, quite a bit of it! Let's review the ones that I find the most important.

There is a model of player engagement called PENS (Player Experience of Need Satisfaction) which is quite rigorously researched. It uses the following criteria to evaluate what a player thinks about a game.
  • Competence. This is how well a game satisfies our need to feel competent - the sense of having mastered the game. 
  • Autonomy. How much freedom does the player have and what options do they have to express it?
  • Relatedness. How well is the player's desire to connect with other people satisfied?
Measuring how well a game performs on the above metrics has been shown to be a much better indicator of various types of success (sales, how likely people are to recommend the game, and so forth) than simply asking if the game is "fun". 

And, more importantly, two of the above factors are directly related to planning. Both Competence and Autonomy heavily rely on the player's ability to plan. Let's go over why this is so.

In order for a player to feel competent at a game they need to have a deep understanding of how the game works. Sure, there are games where mere reflexes are enough, but these are always very simplistic. Even in most rhythm games there are certain rules that the player needs to learn and understand in order to play well. A big part is also learning the melodies that make up each level. Why? In order to optimally place your inputs (be that fingers or feet) to hit as many beats as possible. All of these aspects boil down to one thing: being able to predict the future.

You see the same thing in most games. You get better at Darks Souls when you understand how monsters attack, how levels are laid out and how your own attacks work. Learning how a world operates and gaining the ability to predict is a cornerstone of competence. Sure, you also need to develop the motor skills to carry out the required actions, but this is almost always less important than understanding the whys and whens of the actions. Simply being able to predict is not enough, you also need to have a sense of what goal you are trying to achieve and then, using your predictive abilities, to carry out the steps required to reach it. Or in other words: you need to be able to plan.

Autonomy is also highly dependent on the ability to plan. Imagine a game where you have plenty of freedom, but have no idea how the game works. Everybody who has booted up a complex strategy game without understanding the basics knows that this is not very engaging. In order for the freedom to mean something, you need to have an idea what to do with it. You need to understand how the game's mechanics behave, what tools are at your disposal, and what goals you want to achieve. Without this, freedom is confusing and pointless.

So in order to provide a sense of autonomy a game needs to not only provide a large possibility space, but also teach the player how the world works and what the player's role in it is. The player needs to be able to mentally simulate various actions that can take place, and then come up with sequences that can be used to attain a specific goal. When you have this, you have freedom that is worth having. It should be pretty obvious that I am again describing the ability to plan. A world in which the player is not able to plan is also one with little autonomy.

Similarly, if the game only features a linear sequence of events, there's not much planning to be done. In order for the player to be able to craft plans there need to be options. This is not the case if only a certain chain of actions is possible. This scenario is a typical example of having no freedom, and unsatisfactory in terms of autonomy.  Again, planning and autonomy are intricately linked.

One could make the case that Relatedness also has a connection with planning. As explained earlier, any social interactions heavily rely on our ability to plan. However, I don't think this is strong enough and the other two aspects are more than enough. Instead let's look at evidence from a different angle.


One trend that has been going on for a long time in games is the addition of extra "meta" features. A very common one right now is crafting, and almost all big games have it in some way or another. It's also common to have RPG-like levelling elements, not just for characters, but for assets and guns as well. Collecting a currency that can then be used to buy a variety of items also turns up a lot. Take a look at just about any recent release and you are bound to find at least one of these.

So why do games have them? The answer to that is quite easy: it makes the game more engaging. The harder question is why that should be the case. It can't solely be because it gives the player more to do. If that was the case you would see games adding a random variety of mini games to spice things up. But instead we are seeing certain very specific types of features being used over and over again.

My theory for this is that it's all to do with planning. The main reason that these features are there is because it gives the player a larger possibility space of plans, and more tools to incorporate into their planning. For instance, the act of collecting currency combined with a shop means that the player will have the goal of buying a particular item. Collecting a certain amount of currency with a view to exchange it for goods is a plan. If the desired item and the method in which the coins are collected are both connected to the core gameplay loop, then this meta feature will make the core loop feel like it has more planning that it actually has. 

These extra features can also spice up the normal gameplay. Just consider how you need to think about what weapons to use in combat during The Last of Us. You have some scrap you can craft items from, and all of those items will allow you to use different tactics during combat. And because you cannot make all of them, you have to make a choice. Making this choice is making a plan, and the game's sense of engagement is increased. 

Whatever your views on this sort of meta-feature are, one thing is certain: they work. Because if they weren't we wouldn't be seeing this rise in them persist over such a long time. Sure, it's possible to make a game with a ton of planning without any of these features. But that's the hard way. Having these features is a well-tested way to increasing engagement, and thus something that is very tempting to add, especially when you lose a competitive advantage by not doing so.


Finally, I need to discuss what brought me into thinking about planning at all. It was when I started to compare SOMA to Amnesia: The Dark Descent. When designing SOMA it was really important for us to have as many interesting features as possible, and we wanted the player to have a lot of different things to do. I think it is safe to say that SOMA has a wider range of interactions and more variety than what Amnesia: The Dark Descent had. But despite this, a lot of people complained that SOMA was too much of a walking simulator. I can't recall a single similar comment about Amnesia. Why was this so?

At first I couldn't really understand it, but then I started to outline the major differences between the games:
  • Amnesia's sanity system
  • The light/health resource management.
  • Puzzles spread across hubs.
All of these things are directly connected with the player's ability to plan. The sanity system means the player needs to think about what paths they take, whether they should look at monsters, and so forth. These are things the player needs to account for when they move through a level, and provide a constant need to plan ahead.

The resource management system works in a similar fashion, as players need to think about when and how they use the resources they have available. It also adds another layer as it makes it more clear to the player what sort of items they will find around a map. When the player walks into a room and pulls out drawers this is not just an idle activity. The player knows that some of these drawers will contain useful items and looting a room becomes part of a larger plan. 

In Amnesia a lot of the level design worked by having a large puzzle (e.g. starting an elevator) that was solved by completing a set of spread out and often interconnected puzzles. By spreading the puzzles across the rooms, the player needs to always consider where to go next. It's not possible to just go with a simple "make sure I visit all locations" algorithm to progress through the game. Instead you need to think about what parts of the hub-structure you need to go back to, and what puzzles there are left to solve. This wasn't very complicated, but it was enough to provide a sense of planning.

SOMA has none of these features, and none of its additional features make up for the loss of planning. This meant that the game overall has this sense of having less gameplay, and for some players this meant the game slipped into walking simulator territory. Had we known about the importance of the ability to plan, we could have done something to fix this. 

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A "normal" game that relies on a standard core gameplay loop doesn't have this sort of problem. The ability to plan is built into the way that classical gameplay works. Sure, this knowledge can be used to make such games better, but it's by no means imperative. I think this is a reason why planning as a foundational aspects of games is so undervalued. The only concrete example that I have found[1] is this article by Doug Church where he explains it like this:
"These simple, consistent controls, coupled with the very predictable physics (accurate for a Mario world), allow players to make good guesses about what will happen should they try something. Monsters and environments increase in complexity, but new and special elements are introduced slowly and usually build on an existing interaction principle. This makes game situations very discernable — it's easy for the players to plan for action. If players see a high ledge, a monster across the way, or a chest under water, they can start thinking about how they want to approach it. 
This allows players to engage in a pretty sophisticated planning process. They have been presented (usually implicitly) with knowledge of how the world works, how they can move and interact with it, and what obstacle they must overcome. Then, often subconsciously, they evolve a plan for getting to where they want to go. While playing, players make thousands of these little plans, some of which work and some of which don't. The key is that when the plan doesn't succeed, players understand why. The world is so consistent that it's immediately obvious why a plan didn't work. "
This is really spot on, an excellent description of what I am talking about. This is an article from 1999 and have had trouble finding any other source that discuss it, let alone expands upon the concept since then. Sure, you could say that planning is summed up in Sid Meier's "A series of interesting choices", but that seems to me too fuzzy to me. It is not really about the aspect of predicting how a world operates and then making plans based on that.

The only time when it does sort of come up is when discussing the Immersive Sim genre. This is perhaps not a big surprise given that Doug Church had a huge part in establishing the genre. For instance, emergent gameplay, which immersive sims are especially famous for, relies heavily on being able to understand the world and then making plans based on that. This sort of design ethos can be clearly seen in recent games such as Dishonored 2, for instance [2].  So it's pretty clear that game designers think in these terms. But it's a lot less clear to me that it is viewed as a fundamental part of what makes games engaging and it feels like it is more treated like a subset of design.

As I mentioned above this is probably because when you take part in "normal" gameplay, a lot of planning comes automatically. However, this isn't the case with narrative games. In fact, narrative games are often considered "lesser games" in the regard that they don't feature as much normal gameplay as something like Super Mario. Because of this, it's very common to discuss games in terms of whether you like them to be story-heavy or gameplay-heavy, as if either has to necessarily exclude the other. However, I think a reason there is still such a big discrepancy is because we haven't properly figured out how gameplay in narrative games work. As I talked about in an earlier blog post, design-wise, we are stuck at a local maxima.

The idea that planning is fundamental to games presents a solution to this problem. Instead of saying "narrative games need better gameplay", we can say that "narrative games need more planning".

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In order to properly understand what we need to do with planning, we need to have some sort of supportive theory to makes sense of it all. The SSM Framework that I presented last week fits nicely into that role.

It is really best to read up on last week's blog post to get the full details, but for the sake of completeness I shall summarise the framework here.

We can divide a game into three different spaces. First of all we have System space. This where all the code is and where all the simulations happen. The System space deals with everything as abstract symbols and algorithms. Secondly we have the Story space which provides context for the the things that happen in the System space. In System space Mario is just a set of collision boundaries, but then when that abstract information is run through the Story space that turns into an Italian plumber. Lastly, we have the Mental Model space. This is how the player thinks about the game and is a sort of mental replica of all that exists in the game world. However, since the player mostly never understands exactly what goes on System space (nor how to properly interpret the story context), this is just an educated guess. In the end though, the Mental Model is what the player uses in order to play the game and what they base their decisions on.

Given this we can now start to define what gameplay is. First of all we need to talk about the concept of an action. An action is basically whatever the player performs when they are playing the game and it has the following steps:
  1. Evaluate the information received from the System and Story space.
  2. Form a Mental Model based on the information at hand.
  3. Simulate the consequences of performing a particular action.
  4. If the consequences seem okay, send the appropriate input (e.g. pushing a button) to the game.
A lot of this happens unconsciously. From the player's point of view they will mostly view this sequence as "doing something" and are unaware of the actual thought process that takes place. But really, this always happens when the player does something in a game, be that jumping over a chasm in Super Mario or placing a house in Sim City.

Now that we understand what an action is, we can move on to gameplay. This is all about stringing several actions together, but with one caveat: you don't actually send the input to the game, you just imagine doing so. So this string of actions are built together in mental model space, evaluating them and then if the results feel satisfactory, only then do we start to send the required input.



Put in other words: gameplay is all about planning and then executing that plan. And based upon all of the evidence that I showed above, my hypothesis is: the more actions you can string together, the better the gameplay feels.

It isn't enough to simply string together any actions and call that a plan. First of all, the player needs to have an idea of some sort of goal they are trying to achieve. The actions also need be non-trivial. Simply having a bunch of walking actions strung together will not be very engaging to the player. It's also worth pointing out that planning is by no means the only thing that makes a game engaging. All other design thinking doesn't suddenly go out the window just because you focus on planning. 

However, there are a bunch of design principles that go hand in hand with planning. For instance, to have a consistent world is crucial, because otherwise it isn't possible for the player to form a plan. This is why invisible walls are so annoying; they seriously impede our ability to create and execute plans. It also explains why it's so annoying when failure seems random. For gameplay to feel good, we need to be able to mentally simulate exactly what went wrong. Like Doug Church expressed in a quote above: when a player fails they always need to know why.

Another example is the adventure game advice that you should always have several puzzles going at once. In planning terms this is because we always want to make sure the player has ample room to plan, "I will first solve this and then that". There are lots of other similar principles that have to do with planning. So while planning is not the only thing that makes a game engaging, a great number of things that do can be derived from it.

Let's quickly look at some examples from actual games.

Say that the player wants to assassinate the guy in red in this situation. What the player does not do is simply jump down and hope for the best. They need to have some sort of plan before going on. They might first wait for the guard to leave, teleport behind the victim, and then sneak up and stab them. When that's done they leave the same way they came. This is something the player works out in their head before doing anything. It isn't until they have some sort of plan that they start acting.

This plan might not work, the player might fail to sneak up on the guy and then he sound an alarm. In this case the plan breaks, however that doesn't mean that the player's plan was totally untrue. It just meant they didn't manage to pull off one of the actions of. If presented properly, players are okay with this. In the same way, the player might have misinterpreted their mental model or missed something. This is also okay as long as the player can update their mental model in a coherent fashion. And next time the player tries to execute a similar plan they will get better at it.

Often this ability to carry out your plans is what makes the game the most engaging. Usually a game starts out a bit dull, as your mental models are a bit broken and the ability to plan not very good. But then, as you play, this gets better and you start stringing together longer sets of actions and therefore having more fun. This is why tutorials can be so important. They are a great place to get away from that initial dullness by making the experience a bit simpler and guiding the player to think in the correct manner about how the game works.

It's also worth noting that plans should never be too simple to carry out. Then the actions become trivial. There needs to be a certain degree of non-triviality for engagement to remain.

Planning doesn't always need to happen in the long term, it can also be very short term. Take this scene from Super Mario, for instance:



Here the player needs to make a plan in a split second. The important thing to notice here is that the player doesn't simply react blindly. Even in a stressful situation, if the game works as it should, the player quickly formulates a plan and then tries to carry out that plan.

Now compare these two examples to a game like Dear Esther:



There are a lot of things one can like about this game, but I think everybody agrees that the gameplay is lacking. What's harder to agree on, though, is what's missing. I've heard a lot about the lack of fail states and competitive mechanics, but I don't find these convincing. As you might guess, I think the missing ingredient is planning.

The main reason that people find Dear Esther unengaging is not because they cannot fail, or because there is nothing to compete against. It's because the game doesn't allow them to form and execute plans. We need to figure out ways of fixing this.

By thinking about the planning in terms of the SSM-framework we get a hint at what sort of gameplay that can constitute "narrative play": When you form a plan in Mental Model space it is important that the actions are mostly grounded in the data received from Story space. Compare the the following two plans:

1) "First I pick up 10 items to increase the character X's trust meter, this will allow me to reach the 'friendship'-threshold and X will now be part of my crew. This awards me 10 points in range combat bonus."

2) "If I help out X with cleaning her room, I might be able to be friends with her. This would be great as I could then ask her to join us on our journey. She seems like a great sharpshooter and I would feel much safer with her onboard."

This is a fairly simplistic example, but I hope I get the point across. Both of these describe the same plan, but they have vastly different in how the data is interpreted. Number 1 is just all abstract system-space, and the number 2 has a more narrative feel, and is grounded in the story space. When the gameplay is about making plans like the second example, that is when we start to get something that feels like proper narrative play. This is a crucial step in evolving the art of interactive storytelling.

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I believe thinking about planning is a crucial step in order to get better narrative games. For too long, game design has relied on the planning component arising naturally out of 'standard' gameplay, but when we no longer have that we need to take extra care. It's imperative to understand that it drives gameplay, and therefore that we need to make sure our narrative experiences include this. Planning is by no means a silver bullet, but it's a really important ingredient. It's certainly something that we're putting a lot of thought into when making our future titles here at Frictional Games.



Footnotes:

1) If anyone has other concrete resources describing planning as a fundamental part of games I'd love to hear about them. Please post about them in the comments if you know any.

2) Steve Lee had an excellent lecture called "An Approach to Holistic Level Design" at this year's GDC where he talked a lot about player intentionality. This is another concept closely related to planning.


Tuesday, 23 May 2017

The SSM Framework of Game Design

This article goes over a framework for understanding how videogames work. It divides games into systems, story, and a mental model, and then shows how these interact. Using this system makes it easier to make design decisions and enables one to have insights into the workings of a game.


I've previously talked about story and mental models, and now it's time to wrap it all up into one neat framework. By looking at how these aspects influence one another it's much easier to talk about a game, and it also allows us to draw some fresh conclusions. In this post I'll go over the basic framework and then discuss how it can be applied to gameplay.

It's worth noting that this is by no means the only way of looking at games, nor does it take into account every single aspect of what games are. I think it's broad enough and covers enough ground to be really useful, though. In fact, it'll be used as a foundation for many of my upcoming articles on design. With that said, let's start.

The first thing you need to realize is that all games work in three different spaces: System, Story and Mental Model. These are the building blocks of the entire framework and I'll henceforth refer to this as the SSM-framework. This theory derives a few of its basics from the MDA framework, so it feels right to briefly go over that. In the MDA framework, games are divided into Mechanics, Dynamics and Aesthetics. The mechanics are the basic building blocks of a game, the dynamics are how they work together, and the aesthetics describe the user experience[1]. All of these different components are layered and dependent, so mechanics give rise to dynamics and dynamics give rise to aesthetics.

While I think the MDA approach to looking at games can be really helpful, it doesn't properly separate the player's understanding of the game from the actual behaviour of the game. That's the main thing that the SSM Framework tries to fix. The way it does this is by viewing a game as something that takes place in the three spaces I mentioned earlier: Story, System and Mental Model. Now let's go through each of these.

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System
The System space is where all of the code exists and where all of the game simulations happen. It's here that things get done. We can divide this space into two layers: Mechanics and Dynamics. This is incredibly close to the MDA framework, with the exception of the Aesthetics layer. It's also important that the mechanics and dynamics here are abstract; we don't take any account of how they are presented to and understood by the player. System space only concerns itself with functionality.


Story
Story, as explained in this previous post, is what gives context to the things that happen in System space. In Super Mario's system space, a fireball is just an abstract object with bounds that trigger a particular event on collision. It's in Story space that it looks like a fireball, which helps the player intuitively understand what sort of threat they are dealing with. Sometimes the Story space is very thin. For instance, in Tetris the visuals are basically just a direct visualization of the system space. In other cases, the Story space can be very thick. A good example of that is The Walking Dead where the systems are supported by hours of non-interactable Story-space cutscenes.

Just like the System space can be divided into two layers, so can Story space. At the bottom layer we find the Mis-en-scéne, which is basically everything that the player can see, hear, and in other ways reach their sensory organs. This is a term borrowed from film and I think it best encapsulates this component of the story layer. In the layer above that we find Drama. Just like the Dynamics of System space, this is something that is generated by the layer below, in this case the Mis-en-scéne. Here's a quick example of this: In Super Mario, the character of Bowser is part of the Mis-en-scéne and the fact that he does not like Mario is Drama. Just like with Mechanics and Dynamics, there is some overlap between the two, but they are still separated enough for it to be a useful distinction.


Mental Model
Finally we arrive at the Mental Model space. It's hard to quickly summarize exactly what a Mental Model is, and the best thing really is to read the previous blog that discusses the subject. In very simplistic terms the Mental Model is the player's personal experience of the game, making it similar to the Aesthetics of the MDA framework. The big difference is that while it does derive from what happens in a game's Mechanics and Dynamics, it is thought of as its own separate space. When you join together the three different spaces, it looks like this:


It is when the Story and System space are experienced together that a Mental model is formed. I think it's incredibly important to think of this as a separate space, because just like System and Story have their components, so does the Mental Model. At the basic level you find Affordances. This is basically the functionality that the player attributes to a perceived object, e.g. that a door is something that can be opened. Then at a layer above that you find Schemas, which is how the player thinks they should behave in various situations and how these situations ought to play out.

This is a quite rough division of layers and as before there is overlap. There are also further details to take into account, such as the player's emotional responses and so on. Normally, you wouldn't think of these as part of, say, Affordances, and if you wanted to you could make the components of the Mental Model space quite complex. I feel that for a framework to be useful it needs to simplify things and as a start Affordances and Schemas work quite nicely. It's not at all that different from Mechanics and Dynamics; these are widely used concepts in game design despite not being exact expressions.

A final important note about the Mental Model space is that it doesn't necessarily need to contain things from either System or Story space, it can be things that the player makes up from their own imagination. For instance, certain items might disappear when they are out of view for a long time. The player might form the Mental Model that that this is due to some gnomes, despite neither System nor Story space contains any such information. This is very common, and a large part of the Mental Model space is usually taken up by these kind of imaginary entities, actions, etc. Sometimes a game is designed for this, other times it is purely accidental.

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With the basics laid down let us discuss how the SSM Framework describes a game loop. Here is a an overview for how it all works:


Click to enlarge.

The steps are as follows:
  1. The users triggers an input on the controller and this data is sent to System space.
    Example: The fire button is pushed.
  2. System space handles the data, does all the required simulations and then generates a bunch of abstract data.
    Example: The trajectory of the bullet is calculated, a collision is found, the hit points are lowered for the object and this causes the object to transition into the "exploded" state.
  3. This abstract data is sent to the Story space, where it is given context.
    Example: The game changes various numbers which are used by various graphics components to produce output. The "exploded" event triggers a particular sound file to be played.
  4. A collection of sounds, animations, graphics and so forth is produced.
    Example: The bullet is animated as a flying projectile. It is seen hitting a barrel which then explodes to the sound of a loud "Boom!".
  5. This Story generated content gets sent to the various sensory organs of the player. The most common are the eyes and ears.
    Example: The player hears and sees the explosion.
  6. The player's sensory organs sends the data to the brain where it is processed in various ways. We are now entering the Mental Model space of the game loop.
    Example: The player recognizes the bullet and barrels as those objects. It's also clear that the bullet hitting the barrel caused an explosion event. This, together with the boom sound, gives the player a feeling of satisfaction.
  7. The player's impressions are fed into the current mental model.
    Example: This is the first time the player witnesses a bullet making a barrel explode.
  8. Using the new data, the mental model is updated.
    Example: The player is now aware that shooting barrels will make them explode and cause satisfying effects.
  9. The player uses the most recent model to figure out what to do next and simulates what effects various scenarios would have.
    Example: The player is surrounded by barrels and knows that their goal is to destroy as many objects as possible. They consider what would happen if they were to shoot at more barrels. A mental simulation is made where the result of shooting the other barrels would make them explode as well, causing a lot of carnage, which brings the player closer to their goal. This feels like a good plan.
  10. With a plan for what to do next, commands are sent for the player to trigger the game's input device.
    Example: The player's brain sends signals telling their hands to move the stick and hit the fire-button in such a way that it should hit the nearby barrels.
And then then it all loops back to step 1 again and begins all over. Hopefully this gives an idea of how useful the SSM Framework is in describing the game loop. Once you have this sense of how data is formed and transported around as a game is played, it's much simpler to see where something goes wrong. 

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Now for a simple example of how this framework can be helpful when analyzing input. Hopefully this will also show how SSM can help us discuss certain game design problems in a much simpler way. 

Let's start by imagining a System space that has the following: 

  • A character where the bounds are defined as an abstract cylinder.
  • An abstract device that will play sound files when certain events are triggered.
  • A couple of rules that will make the cylinder character stay at a certain distance from the player.
Now say that the Story space looks like this:

  • The cylinder takes the form of a cute rabbit.
  • The sound files played are cute quips that the player is meant to find endearing.
The designer's goal is that the rabbit should be something that the player cares about. If the Mental Model gets constructed properly the player will think of the rabbit as a living creature and base their imagination mainly on the story aspects of the character. This makes the player protect the rabbit and makes sure that it never falls too far behind. This is a case of the Mental Model working as desired.

However, it might be that the player realizes that the rabbit is a great shield against incoming enemy attacks. The game becomes much easier to play if the player manages to position the rabbit in between them and any hostiles when it's time to loot treasure chests. 

This radically changes the player's mental model. Instead of being a living creature, a fantasy mostly derived from Story space, the player now sees the character mostly as an element of System space. The rabbit is now simply a handy game object that has various tactical benefits.

This sort of thing is quite common in games. Entities usually start out in story space and then as you play the game and discover how they actually work, your mental model becomes more influenced by System space. And since the story content can usually deliver a lot more emotional depth, the experience comes off as very "gamey". In some cases this can be perfectly fine, but when you want to deliver a narrative experience it can be devastating. In this case it's really important to keep our Mental model close to what we had in Story space.

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These sort of story vs gameplay issues are really easy to discuss in the SSM Framework, and it also provides us with several avenues of attack for how to solve them. You need to make sure that System space doesn't generate Mentally Modeled behaviors that directly contradict what is in Story space. By thinking about the flow of data in the game loop you can pinpoint where it all went wrong and then change things accordingly. While this doesn't spell out every single step needed to fix the problem, it gives us a way to formulate it and a foundation on which we can lay a more detailed plan.

Next week I will go over how the gameplay is defined in the SSM Framework and how it shows us a way to give narrative games a great sense of play.




Footnotes:
[1] The MDA framework also brings up various ways in which games engage players, but that I felt no need to go over that in this article. Do note that there is more to the framework than simply 3 layers of components.