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Chapter 3. The Game Feel Model of Interactivity
3.1 The model of interactivity brings together all the elements of the the gamer, the game and the world around him or her.
THE HUMAN PROCESSOR
knowledge: generalizations, ideas, concepts and misconceptions about the nature
of the world. All of these things are integrated into the perceptual field as they are
The avatar is the player’s instrument within the game world, both for perception
and for expression. The movement of the avatar provides indirect insight into the
nature of the game world the same way our own hands may touch and probe and
noodle things around in order to experience them while our eyes and ears observe
the results. Perception requires action, as we’ve said, and all perception of a game
world must pass through the avatar.
With those three elements in mind, let’s step through Figure 3.1 and try to “bring
alive” the active process of game feel. Remember, this whole thing is happening at
a cycle time of around 240 ms, four or five times per second. Let’s start with the
human processor—the player.
The Human Processor
The human process is marked at “1” in Figure 3.1. Stimulus comes in through
the eyes, ears, fingers and proprioceptive senses. It is perceived at a cycle time
between 50 and 200 ms, depending on individual and circumstance. If two stimuli
are perceived within the same perceptual cycle, they appear fused, as with multiple
frames of an animation fusing into a single, moving character. If an action passes
out through the motor processor and the response is perceived in the same perceptual frame, there is a strong bias toward experiencing action and response as causal
(“My action caused this result”).
If this is an ongoing process, where perception, action and contemplation of the
same object happen in rapid succession over and over again, the experience is one
of control fusion—through my actions, I feel I am controlling something external to
me. This is what enables us to pick things up and move them, to throw and catch
things, and to generally interact skillfully with our immediate bodily surroundings.
When this process of ongoing control is able to flow uninterrupted and the
intent being served is more complicated than a single, simple action (grabbing
a muffin, for example) then we have a correction cycle, which happens around
240 ms and which is, at its core, the experience of game feel. As this process is running, the perceptual field is in the background coloring, ordering and assigning meaning to all new experiences. As soon as the experience happens, it is incorporated into
the perceptual field, expanding it. Skills are built, memories are formed, life is lived.
Marked at “2” in Figure 3.1, the impulses from the human processor flow out
into the real world. The muscles of the hand execute the orders handed down by
the motor process, which has in turn been directed by the cognitive process. In
CHAPTER THREE • THE GAME FEEL MODEL OF INTERACTIVITY
addition, the hand provides tactile and proprioceptive feedback to the perceptual
processor, the “megaphone for your thumbs” mentioned in the Chapter 1 section on
game feel as proprioception.
The input device is marked at “3” in Figure 3.1. The input device is the player’s
organ of expression to the computer. All intent passes through the filter of the input
device before it can be interpreted by the system and used to update the state of the
computer’s model of the game’s reality, which is different from the player’s. The
motivation and experience of the player are more complicated than this in many
ways, but if the goal is to better understand the pieces of game feel that are malleable to the game designer, it’s convenient to think in these simplified terms. The
player has a particular intent at a given moment in time, and he or she expresses
that intent to the system via the input device. Whatever the input device is, it has
affordances and constraints. It will lend itself to controlling certain kinds of motion
more readily than others and has its own physical feel and character which will
ultimately affect the experience of game feel as perceived by the player.
The computer is “4” in Figure 3.1. In one sense, the computer does its own perceptual, cognitive and motor processing. It accepts input at a certain rate, thinks
about it for a certain amount of time, and then responds, sending signals to its output devices. As with the human processors, the computer has a cycle time for this
whole endeavor. In the case of the computer, though, the response needs to happen
quickly enough for the player to perceive the response as instantaneous—within
one perceptual cycle (as little as 50 ms) of receiving input from the player.
For game feel to occur uninterrupted, input from the player’s muscles needs to
travel through the controller, be processed and come back as changes in pixels and
sounds before one entire cycle of the player’s perceptual processor has finished. The
computer needs to perform its half of the cycle faster than the player can perceive. If
this occurs, the player will see the series of incrementally changed visual frames as
a single moving object and will feel it reacting immediately to the input. The player
will readily interpret a cause and effect relationship, and the impression of control
The Game World
The game world is marked “5” Figure 3.1. For our purposes, the game world exists
primarily in the player’s mind. There is also an internal representation of the game
world that exists in the computer, one which is more precise and mathematical than
the rich, expressive world experienced by the player. But a game system is designed
to output to an experience in the mind of the player. For the player, the output
devices are a window into the game world, and the avatar acts as a proxy within
that world. The player perceives the game world actively, through the “body” of
the avatar. Experiencing game feel is feeling out the game world, making additional
distinctions, and learning skills, concepts, and generalizations that make coping
with the unique world easier.
This is essentially the same process we undergo in our everyday lives. A game
world slots itself into the player’s action → perception → cognition cycle, replacing the physical world’s roles of accepting input and returning feedback. A game
world is simpler, easier to understand, and has clear, finite goals. This makes learning game skills faster, easier to measure, and, in many ways, more appealing than
Marked at “6” in Figure 3.1 is the output device. The output devices, which may
include a monitor, speakers, controller’s rumble motors, haptic feedback device and
so on, are the player’s window into the game world. The monitor and speakers are
where the processing of the computer reaches reality. They are the computer’s organs
of expression to the player. The completed processes have resulted in an updated
system state for the computer, and it sends visual, aural and tactile feedback out
through its various channels into the world and, as we looked at in Chapter 1, the
position of the hands or other body parts on the input device offers the player proprioceptive feedback which can be reconciled with what’s happening on the screen
or coming through the speakers. Moving my thumb this far moves the character too
fast, so I subconsciously ease off the thumbstick by a millimeter or two.
The loop is complete at the player’s sense, marked “7” in Figure 3.1. The senses
take in the updated state of the game world. The eyes, ears and hands (both tactile
and proprioceptive senses) perceive the new, changed state of the game’s reality
and pass them along to the perceptual processor. The cycle, having taken less than
half a second, is complete. The motions are amplified into the game world but still
have a real-world position that’s being perceived by the hands via the proprioceptive sense.
I’m keeping the Model Human Processor and meshing it with the perceptual
field. In my model, the perceptual field is fused with the perceptual and cognitive
processors, being at once a filter for new perceptual information, a framework in
which to slot it, and an ever-expanding reference library which contains not only
information about the meaning to assign each new stimulus but your schematic
diagrams of your world and everything in it.
CHAPTER THREE • THE GAME FEEL MODEL OF INTERACTIVITY
The Player’s Intent
To complete our model, we need to account for intent. On one level, it’s an interesting question: where does intent come from? What motivates us to do what we
do? This question is perhaps more satisfying as applied to game worlds because
it can be answered definitively. Intent in a game world is designed by a game’s
creator; we don’t have to wonder at its origins, divine or otherwise. As for real-world
intention, French Philosopher Maurice Merleau-Ponty thinks that people have an
“in-born intentionality towards the world.” To say: “we’re born with it,’” though,
seems like a bit of a cop-out.
Maslow has some more interesting things to say about the nature of human
motivation with his pyramid of wants (see Figure 3.2). At the bottom are things like
satisfying your basic physical needs for food, shelter and warmth. Moving up, you
find security, love, self-esteem and, finally, self-actualization. The idea is that at any
time, if one of the lower rungs is unsatisfied, consciousness dips down to that base
level until that need is sated. People are constantly trying to reach higher and higher
on the pyramid, striving for creative satisfaction and whatnot. Sims, it seems, have
a hard time getting above the toilet level.
The pyramid fits with how Snygg and Combs incorporate intentionality and
motivation into their perceptual field. They envision a “perceptual self”—the vision
of yourself that exists as part of your own perceptual field. This is a cool concept, as
it seems to explain things like those self-immolating Tibetan monks from the Rage
Against the Machine album cover. A person can do things that don’t seem to serve
his or her body very well—lighting oneself on fire being one possible example—
but which enhance the perceptual self. You see yourself as a martyr, dying for a
3.2 Maslow’s hierarchy of needs starts with the basic physiological needs and
moves upward to self-actualization.
cause greater than yourself. Thus your own self-image, the embodied qualities of
yourself as you perceive you, is enhanced. And made more crispy.
Whatever the origin of human motivation is in reality, though, it is true that
part of game design is crafting goals, implicit or explicit, to motivate action in game
worlds. This is one of the dark arts of game design—creating meaningful, compelling intent from a seemingly arbitrary collection of abstracted variables. Think,
for example, of the coins in Super Mario 64. Ask yourself: if you didn’t get a star
for collecting 100 coins or if they did not restore Mario’s health, would you bother
collecting them? No, of course not. These are the arbitrary relationships between
abstract variables that give coins meaning in the game world of Mario 64. The star
itself is given meaning only by being rare and powerful, one of only 120 in the
whole game, each of which is a clear, measurable step toward unlocking the entirety
of the game’s levels, the (explicit) goal of defeating Bowser or the (implicit) goal of
collecting all the stars.
This is one of the most appealing aspects of video games for many players.
A game world’s logic is simple, easy to understand, and provides clear incentives,
rewards and feedback for effort invested. It’s safer than the chaotic and arbitrary
nature of everyday life. It’s comforting. In many cases, it rewards mediocrity or
at least makes it ignorable. Whether this is good or bad is a different question, but
it is worth noting that most game worlds do in fact have in-born intentionality, and
it’s the game designer who creates it.
The game feel model of interactivity offers a comprehensive picture of how game
feel occurs as a process. Each element involved in the process—the human processor, human muscles, input device, the computer, the game world, output devices,
the senses and the player’s intent—is necessary to keep the cycle running.
1. The human processor—where perception and thinking happen and motor
instructions are created.
2. Muscles—The motor instructions are executed as muscle movements.
3. Input device—The muscle movements are translated into a language the computer understands.
4. The computer—Where all processing happens, including integration of input
with the current state of the game world.
5. The game world—The computer’s internal model of the game’s reality.
6. Output devices—The updated game state is output into a form the player can
7. Senses—The player perceives the updated state through sights, sounds, touch,
CHAPTER THREE • THE GAME FEEL MODEL OF INTERACTIVITY
The player’s side of things does not change because of the fixed properties of
human perception, which limits the game designer’s area of influence. On the computer side of things, a designer is unlikely to have a role in creating the input device,
the computer or the output devices. The game designer’s palette, then, is contained
within steps 4 through 6.
Examining all the pieces in a cohesive model, we can finally make a firm delineation between games that have game feel and those that don’t. The model provides
a framework for understanding where things might be improved in a particular
design, and a foundation for creating game feel from scratch.
To wrap up our section on defining game feel, let’s apply all the ideas from Chapters
1, 2 and 3 to some specific games. To do this, we’ll return to our three-part definition of game feel: real-time control, simulated space and polish. The overall question to be answered is where a game fits on the diagram (Figure 4.1).
This breaks down, once again, into three questions:
1. Does it have real-time control?
2. Does it have simulated space?
3. Does it have polish?
4.1 Types of game feel: we want to put every game somewhere on the diagram.
CHAPTER FOUR • MECHANICS OF GAME FEEL
From our model, we have measurable thresholds for real-time control to test
10 frames per second. The images are displayed at a rate faster than one cycle of
the human perceptual processor, which will be 50 to 200 ms. Therefore, images
displayed at a rate at or above a rate of 10 frames per second will appear fused
into motion, and 20 frames per second or higher is necessary for a smooth
motion. In the case of a game, this is not a series of linear frames played back in
sequence but a series of states generated in response to input.
Response time of 100 ms or less. The game’s response to input happens within
one perceptual cycle (50 to 200 ms) of the player’s action, fusing into a sense of
causality and instantaneous response.
A continuous feedback loop. The game provides a continuous, unbroken flow of
input and instant response, enabling ongoing correction cycles to occur.
But these metrics are difficult to apply to an entire game’s interactivity all at once.
To answer the question of real-time control more easily, it’s useful to break down a
game’s interactions into individual mechanics. Then we can check each mechanic
against the various thresholds from our model.
Mechanics: Game Feel Atoms
For our purposes, a “game mechanic” is one complete loop of interaction, such as
a single mouse twitch, button press or foot stomp that can be traced through the
game’s programmed response and back to the player over and over again. Another
way to think about mechanics is as verbs. What are the player’s abilities in the
game? What can the player do? By this definition, examples of individual mechanics
Pressing the A-button to jump in Super Mario Brothers
Steering Mario left and right using the D-Pad in Super Mario Brothers
Strumming a note in Guitar Hero
Using the mouse to steer left and right in flow
Boosting forward by clicking the mouse in flow
Drag-selecting a group of units in Starcraft
Clicking to send a group of selected units to a new location
Pressing a button at the right moment to advance to the next sequence in
Clicking on a button to select the next technology to research in Civilization 4
In a typical game, many different mechanics are active at the same time and often
overlap and combine. Running and jumping in Super Mario Brothers are separate