INTRODUCTION

Our group was tasked with the challenge of developing a game using mobile phone

technology for children in the age group of 12–14. The primary interface design goal

was to have the gameplay and interaction not screen-based but instead situated in

physical space. During the prototype session where we tested our initial game

design, we realized the issue of space and the physical environment loomed large

during the design phase of our mobile phone game; this is a problem that purely

screen-based games do not have to address, but as game technology transcends the

present dominant mode of screen-based interactivity and the reality of games

becomes more augmented, the presentation of space and the gamers’ interaction

within it must be addressed.

MIXED-REALITY AND LOCATION-BASED GAMES

Mixed-reality games attempt to revive facets of gaming that are difficult to achieve by

the typical screen-based computer or video game: the social interaction, co-location,

tactile, and visual qualities of traditional games. Games were designed and played

out in the physical world, making use of real-world properties, such as physical

objects, sense of space, spatial relations, and social interaction according to the

game rules. In these games, we have the full level of physical and social interaction

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within the game context. The extent of interaction is only limited by the game rules

(Cheok et al, 430).

A subset of mixed-reality games, location-based games, provides a taxonomical

classification for games that rely on mobile devices in the real-world environment.

Various research fields of Human-Computer Interaction contribute to the knowledge

base needed for the implementation of location-based games:

· Ubiquitous computing — the use of embedded computer technology in the

environment, in objects, and in the background to support users’ activities wherever

and whenever needed

· Social computing — places the real-time and real-space activities of humans

as social beings at primary importance

· Tangible interfaces — physical instead of digital interfaces, allowing users to

manipulate data in a virtual environment by the manipulation of a corresponding

physical object (Lundgren & Bjork, 2)

· Embodied computing — a next generation computing paradigm which involves

the elements of ubiquitous computing, tangible computing, as well as social

computing. It places computation and interaction throughout and with the

environment, as well as incorporating the sociological organization of interactive

behavior (Cheok et al, 433).

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CHALLENGES POSED BY THE REAL-WORLD ENVIRONMENT

As the majority of mobile interface testing is conducted in laboratories or

comparable staged areas for easier observation and data collection, some usability

researchers have been concerned that “laboratory evaluations do not simulate the

context where mobile phones are used and lack the desired ecological validity.

Interruptions, movement, noise, multitasking etc. that could affect the users’

performance are not present in laboratory tests” (Kaikkonen et al, 5). When

designing games for a mixed-reality space created by the merging of physical and

virtual space, real-world factors not found in laboratory settings—if not addressed

during the game design—could significantly affect the immersion of the players in

the game space.

Typical challenges found in the testing of location-based games in the real-world

environment are interruptions, lack of personal space or privacy, and network

blackspots (areas where the mobile devices could not receive service) (Crabtree,

398). The Citywide project, which studied various ways in which technology could

enhance experiences of the physical space of cities, discovered that the users of the

mobile devices needed multiple means of feedback regarding their wireless

connection status to avoid breaks in the augmented digital experience. To further

enhance the event, the Citywide project combined the mobile devices with the use of

fixed technologies, such as large screen displays, projections, and ambient audio

(Izadi et al, 293). These stationary artifacts aided in the presentation of the game

space and the outlying non-game space as a more consistent visual display. These

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fixed technologies also provided a common artifact through which the gamers and

the general public could interact and communicate without necessarily breaking the

flow of the game space.

THE FLOW

To create a unique space for a location-based game within the real world, “one has

to establish the limits of playing space, but in addition, one needs to restrict this

territory with respect to rule-binding criteria for adaptation and interaction”

(Walther, 4). The theory of flow, introduced by the psychologist M. Csikszentmihalyi,

defines an optimal experience as “the sensation of oscillating between ecstasy . . .

and goal-orientation in play. . .” (Walther, 3).

Games differ from un-structured play; to sustain a player’s immersion in a game

plot requires adherence to stricter constructs than those associated with play.

During simple play, a participant’s locus of attention can volley between play and

non-play without significant disruption to task completion; in contrast, “game-mode

presses forward one’s tactical capabilities to sustain the balance between a

structured and an un-structured space.” Games are “confined areas that challenge

the interpretation and optimizing of rules and tactics—not to mention time and

space” (Walther, 1). Articulating the boundaries between the structured game space

and the rest of the world can be difficult when attempting to incorporate the game

into physical space with little technological intrusion. George Spencer-Brown’s Law

of Form explains that a new contextual realm comes into being when a space is

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separated into the outside and the inside. In a location-based game, environmental

factors become unpredictable; outside objects with which gamers may have potential

interaction become transformed into inside objects that can be utilized in the

gameplay as a point of reference, if not something more influential.

THE BREAKDOWN

A breakdown in a gamer’s mental model, which can occur in numerous ways, will

disrupt the game’s illusion. According to Walther, “If a game breaks illusion—if it

fails to indicate its unity through its difference from its other and itself—one is likely

to be thrown back into play-mode” (Walther, 8). If the plot of the game crumbles and

reminds the gamer of the artificial constructs of the reality in which his perceptions

and resulting actions previously existed, his locus of attention shifts back to reality;

therefore, the game-mode reverts back to play-mode. The gamer is forced to cross

back over the border of the game’s created contextual area into the outside, and the

synchronicity between his mental model of the game and the constructed physical

game space disintegrates.

When preparing for the prototype session of our mobile games with KidsTeam, an

important goal was to maintain a consistent level of abstraction for all artifacts used

in the gameplay. When a mobile location-based game is played in a real-world

setting, the game components should blend in appropriately with the environment

unless the game itself calls for incongruency. This notion of consistency applies to

gameplay regardless of the medium and is mentioned as a pertinent issue by the

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creator of The Sims: “It doesn’t make sense to have everything highly detailed except

one aspect and then have it abstracted. So in fact you want the entire world and the

entire representation to be abstracted at almost the same level” (Pearce,8). During

the design of The Sims, presentation of the game’s virtual objects maintained

consistency, as the juxtaposed fidelities of the artifacts affect the “whole idea of

suspension of disbelief, that if you’re making a world, you need to make sure that

the world has efficacy within itself, at whatever scale or level of detail you’re crafting

it” (Pearce, 17).

CONCLUSION

Thus far, creators of location-based games have aimed at “a new type of game

experience that has two main features: integrated ubiquitous context-awareness and

sociality into the computer interaction context, which entails ubiquitous, tangible,

and social computing (and thus directly applies the theory of embodied interaction);

and a seamless merging of physical world, augmented world and virtual world

exploration experience” (Cheok et al, 441). Location-based games using mobile

devices offer challenges and benefits beyond the realm of fixed-location computer

game design. Interaction takes place not only between the gamer and the computer,

but also between the gamer and the contextual space of the physical world, and the

computer and the physical world. If the broader nature of interaction is considered,

the experience of location-based games will surpass the current screen-based

technological offerings.

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Works Cited

Cankar, M., Kaikkonen, A., Kallio, T., Kankainen, A., Kekalainen, A. 2005. Usability testing a mobile application in the laboratory seems to be sufficient when studying user interface and navigation issues. Journal of Usability Studies. Vol 1, Issue 1. http://www.upassoc.org/upa_publications/jus/2005_november/mobile.pdf Accessed on December 6, 2005. Said, N. S. 2004. An engaging multimedia design model. Proceeding of the 2004 Conference on interaction Design and Children: Building A Community (Maryland, June 01 - 03, 2004). IDC '04. ACM Press, New York, NY, 169-172. DOI= http://doi.acm.org/10.1145/1017833.1017873 Accessed on December 6, 2005. Pearce, C. 2002. Sims, BattleBots, Cellular Automata God and Go: A Conversation with Will Wright. Game Studies. Vol. 2, Issue 1. http://www.gamestudies.org/0102/pearce/ Accessed on December 6, 2005. Addessi, A., Pachet, F. 2004. When Children Reflect on Their Playing Style: Experiments with the Continuator and Children. ACM Computers in Entertainment. Vol 2, No. 2. Accessed on December 6, 2005. Walther, B. 2003. Playing and Gaming: Reflections and Classifications. Game Studies. Vol. 3, Issue 1. http://www.gamestudies.org/0301/walther/ Accessed on December 6, 2005. Bjork, S. & Lundgren, S. 2005. Game Mechanics: Describing Computer-Augmented Games in Terms of Interaction. http://www.cs.chalmers.se/~lundsus/lundgren_bjork_game_mechanics.pdf Accessed on December 6, 2005. Crabtree, A., Benford, S., Rodden, T., Greenhalgh, C., Flintham, M., Anastasi, R., Drozd, A., Adams, M., Row-Farr, J., Tandavanitj, N., Steed, A. 2004. Orchestrating a Mixed Reality Game ‘On the Ground.’ CHI 2004. Vienna, Austria. http://solaria.stanford.edu/stanford/kids/papers/more/p38-koleva%20-%20mixed%20reality.pdf Accessed on December 6, 2005. Izadi, S., Fraser, M., Benford, S., Flintham, M., Greenhalgh, C., Rodden, T., and Schna¨delbach, H. 2002. Citywide: Supporting Interactive Digital Experiences Across Physical Space. Personal and Ubiquitous Computing. Springer-Verlag: London. Accessed on December 6, 2005. Cheok, A., Yang1, X., Ying, A., Billinghurst, M., and Kato, H. 2002. Touch-Space: Mixed Reality Game Space Based on Ubiquitous, Tangible, and Social Computing. Personal and Ubiquitous Computing. Springer-Verlag: London. Accessed on December 6, 2005.