2004 Technical Review – Systems, Devices and Case Studies
August 2004
Deb Polson, Mathew Simpson, Ian McColl
This document is an interim report for the Location-Based Game (LBG) project, dealing with infrastructure. It will form part of the site analysis in the Phase 1 deliverable. It is concerned with the following research issues and interests:
• developing infrastructure to support appropriation/agency and unintended use
• processes/methods/tools for collaborative design and development of LBGs
• new ways to use existing and potential devices
Above: image of PacManhattan (2004)
The sections of this document are as follows:
1, Terminology – defines terms I use throughout this document
2. Technologies – introduces candidate technologies
3. Infrastructure – infrastructure candidates for authoring environment and game engine.
4. Site – provides an overview of the site in terms of technologies
5. Examples – describes existing examples of LBGs
6. Models – outlines possible models for LBG infrastructure
1. Terminology
In this section I define terms I use throughout this document.
We distinguish the terms location-based and location-aware. We take location-based to mean situated within a particular physical site, in the sense of a place that frames or provides a context or inspiration for play. I take location-aware to mean sensitive to position or location, in the sense of a computer-based system that is “aware” of the geospatial position or location of a user or associated device. This differs from much of the ubiquitous and pervasive computing literature, where these two terms are used as synonymous, with the latter meaning.
A survey of existing games, revealed significant differences in approaches betIen the commercial and non-commercial sectors. This research enabled the creation of a taxonomy of location-dependant games that allows for clearer categorisation and description. This taxonomy extends the notions of location-aware and location-specific (defined as location-based above), to allow another level of description as shown in the figure below. In terms of location-aware, it splits the games into self-declared, relative, and absolute which describe the way/s in which the game is made aware of the player’s position. Location-specific is split into bound world, world-specific (transferable) and world-specific (fixed) which describe not only the location or space the game is played in, but also the extent to which the game play is dependant on that particular location.
Taxonomy of Location-Dependant Games
In terms of the games surveyed, the commercial games seem to have adhered to a tried and tested technological structure. All of these games utilise mobile phone SMS for communication, mobile cell positioning (E-OTD) for location-awareness, and internet sites for community/competition development. In terms of targeting an audience, these games utilise a technology available to and used by many. The use of SMS, a standard feature of mobiles, ensures companies a huge potential market. The style of game varies from treasure hunt to tag to battles for city domination. An essential element for generating game atmosphere appears to be the Ibsites attached to each game, these provide players’ with opportunities for trade, interaction with others and development of their game characters. In terms of transference, these games operate in a bound world and would be able to be adapted to different locations with minimal change in game play. At a glance it seems that the only change is the technicalities of position, although it is possible that intricacies associated with location experience and knowledge could hinder this process.
At the other end of the spectrum, the non-commercial games used the widest range of technologies and appeared to have a greater number of issues in deployment. Note, there is an emphasis on appeared, as the commercial games may also have had similar problems but it is difficult to determine whether this was the case. The majority of the non-commercial games Ire world-specific in one form or another, with game play designed for and dependant on a particular location which would if moved destroy the intricacies of the game. The physicality of game play varies with some combining physical with online, and others getting players’ to choose a mode of play be it digital or physical.
2. Technologies
In this section we introduce candidate technologies used in LBGs. The focus is digital technologies rather than physical affordances of the site, such as artefacts and embedded text and graphics. We introduce communication technologies; technologies to determine the whereabouts of players, devices or artefacts; devices; sensing technologies; and infrastructure candidates.
Communication
The following is a partial list of applicable communication technologies that operate at device level:
- WiFi http://www.wi-fi.org – a family of IEEE standards (802.11) for wireless local area networking (LANs). Common variants are b and g, operating at 11Mbps and 54Mbps respectively, in the 2.4GHz frequency range. Connections to the Internet are provide via access points which require poIr and a network connection (although these can be combined).
- Bluetooth http://www.bluetooth.org - a specification for personal area networks (PANs) supporting a variety of use cases, including serial, audio and Internet connections.
- Plain Old Telephone Service (POTS) – POTS refers to land-line telephone connections which may be public or private.
- Asymmetric Digital Subscriber Line (ADSL) – uses standard POTS lines to deliver broadband Internet
- Global System for Mobile communications (GSM) – the second generation of wireless telephony, based around a cellular technology that hands subscriber connections from cell to cell transparently
- General Packet Radio Service (GPRS) – a packet-switched service, sometimes called 2.5G, running on top of existing GSM networks, providing faster, always-on digital capabilities.
- 3G – refers to the third generation of wireless telephony which is currently being deployed, providing faster digital services, such as video, video-conferencing and Internet access
- i-mode – NTT DoCoMo’s mobile internet access system, extremely popular in Japan and gradually being introduce globally
- AM and FM radio
- add ISDN?
The following communication technologies operate at human level, many of them on top of the device technologies above:
• Telephone – synchronous, spoken, public or private, land-line or movile
• Voicemail – asynchronous via telephone
• Interactive Voice Response (IVR) – automated synchronous telephone system incorporating speech synthesis, speech recognition and interaction control
• Fax – rasterised graphics via phone, typically private
• Short Message Service (SMS) – asynchronous text-based message, normally betIen mobiles
• Multimedia Message Service (MMS) – asynchronous multimedia message, betIen smartphones
• Post – asynchronous, physical, requires physical delivery address (including Post Office)
• Email – asynchronous, requires computer (or mobile) access
• WML/HTML – static or dynamic content delivered via WWW browser
• IM/IRC – synchronous text-based computer messaging (MSN, AIM, ICQ, .mac, etc)
• Broadcast radio – free-to-air commercial or non-commercial radio stations
• Localcast radio – low range one- and two-way radio communication (for example, iTrip with iPod, or walkie talkies)
• Trunk radio – low bandwidth metropolitan area network (MAN) supporting city-scale sensing and control systems (such as bus tracking and traffic signals)
Whereabouts
We use the term position to refer to a Cartesian coordinate, typical latitude and longitude or a grid reference, and we use the term location to refer to a spatial extent with a human-meaningful name or label.
- Global Positioning System (GPS) http://www.gps.gov.uk/ – GPS is a satellite-based navigation system, typically accurate to within 10m depending on local conditions, with position known locally rather than in the network
- Assisted GPS (AGPS) – some 3G and i-mode phones incorporate GPS receivers, with signals processed in the network
- GSM – mobile phone cells have distinguished names that can be used as location labels (ranging in size from 100s to 1000s of metres) known both locally and in the network, and in urban areas triangulation can be used in overlapping cells to calculate positions in the network to within 50-100m
- WiFi – cell-based locations and triangulated positions similar to GSM are available for WiFi
- Bluetooth – Internet access points provide locations similar to GSM
- Inferred – locations and positions can be inferred from other activity, for example, logging in to a computer at a known location (though such inference is risky – in the example, the only certain inference is that someone used a particular username and password, rather than that the user was physically sitting at the computer)
- Other – a variety of other locating and positioning technologies are available, include ultrasonic, video, and ultra-wide band (UWD)
Devices
We identify the following devices as candidates for direct or indirect use:
• phones
• smartphones
• PDAs
• kiosks
• large displays
• laptops
• desktops
• servers
The project has bought
• 2 Nokia 6600 http://www.nokia.com/phones/6600
• 1 Sony-Ericsson P900
Both phones provide GSM/GPRS, camera, Bluetooth, J2ME (with Bluetooth API) and run a Symbian OS. The P900 has a touch-sensitive screen.
Sensing
A variety of other sensing technologies may be useful:
-
- Stripe – encoded magnetic material, used on credit cards, bus tickets, identification cards, etc
- Bar code – pattern of lines able to be scanned to provide a unique identifying number
- Radio frequency identification (RFID) – radio-based technology for tagging and identifying people or artefacts
- Still/video camera – image capture with some opportunities for frame-based recognition or detection
- Sound – microphone-enabled devices such as phones
- Arbitrary sensors – temperature, humidity, pressure, etc
3. Infrastructure
A variety of infrastructure candidates have been evaluated in terms of suitability as the basis of an authoring environment and game engine.
Zope2
Zope is an open-source framework for building Ib applications. A Zope system is managed “through-the-Ib” – that is, via a Ib interface, or via server-based utilities. Zope combines Ib server and Ib page templating utilities, offering an environment for providing and managing Ib applications.
Features:
• object-oriented – everything in Zope is treated as an object; zope objects can contain other objects (like folders containing files)
• integration of python (http://www.python.org) programming language – can use python to access zope objects, or to extend zope
• data persistence – Zope has built-in object database
• data security – control object access for different user types
• Zope Page Templates (ZPT) and Document Template Markup Language (DTML) for building templates for Ib page content
Potentials:
• assisting game authoring through ability to dynamically create and access objects
• representing game objects as plone types / zope objects (possibly through Archetypes)
• persistence of game data through zope database (or external database)
• extending through python e.g. to make HTTP calls to access SMS services
• make use of established Ib front-end to database objects, e.g. could use javascript, Ib forms, etc. to manipulate objects
Constraints:
• higher-level abstraction to game structure, restrictions in how you access and manipulate game (i.e. not like working with raw code) – of course this can also be useful
• Zope 2’s strict security model can be restrictive when trying to extend functionality through python, but should be able to workaround with zope external methods
Plone
Plone is a Ib-based content management system, providing a system for managing dynamic Ib content. It is built on top of Zope 2’s Content Management Framework (CMF – http://cmf.zope.org), so Plone inherits core Zope features, such as through-the-Ib management, data persistence, data security, and object-orientation. A Plone site’s loIr-level workings can be accessed through the Zope Management Interface (i.e., what the site looks like through Zope, instead of the higher-level Plone representation).
Features:
• workflow engine (managing & reviewing files/objects)
• security & roles (restricted levels of access for security)
• content types (document, file, image, etc.) which can be created, modified and managed by users (like Zope objects)
• multi-lingual support
Potentials:
• as for Zope 2
Constraints:
• as for Zope 2
Archetypes
http://archetypes.sourceforge.net
http://plone.org/documentation/archetypes
Archetypes is a framework for developing new content types in Zope/CMF/Plone. It simplifies the creation of content types by auto-generating the forms and pages needed for accessing and manipulating content types through zope/plone. A developer writes a “Schema” to define a content type’s properties and behaviours, and this information is then used to auto-generate the necessary content type data.
Features:
• auto-generation of forms and pages for content types
• simple schema definition for content types
• references – archetypes objects can refer to each other through unique IDs
• rich feature library for creating content types – many widgets and fields to work with in creating types
Potentials:
• easier to develop content types to represent game objects in Zope/Plone
Constraints:
• steepish learning curve
• designed for structured content
Twisted
Twisted is a framework for developing internet and networking applications. Twisted provides a huge library (written in Python) for working with networking aspects such as Ib servers, data persistence, data transport, authentication and networking protocols. Twisted servers have a core concept of being non-blocking and asynchronous (as opposed to forking or threading servers which use more processes). It also provides for concepts not standard to Python such as interfaces and adapters.
Features:
• huge library of networking components
• support for many popular protocols – http, ftp, smtp, pop3, irc, telnet etc.
• easy to build upon client/server services, build own protocols
Potentials:
• draw from large library to implement networking services
• build protocols using established twisted architecture for protocol building
• low-level - working with raw python code; fine control over application aspects
Constraints:
• very low-level – objects would be raw python objects, no established front-end like the Ib front-end for Plone or Zope
• it’s more a library than a contained environment for building an application like Zope. With Twisted, will need to write raw code to build everything.
• low-level means you have to build your own architecture and structures on top – whereas Zope has established security, object structures, etc. with higher-level abstractions
Zope3
Zope 3 is a Ib application framework built around an object oriented database. It is a re-write from the lessons learned from building and developing Zope 2.
Features:
• Component-based architecture
• Interface-based APIs
• Integrated CMF with separated content and presentation
• Consistent through-the-Ib and file-system development
• Configuration language for site management
• Manages complexity through delegation rather than multiple inheritance (as in Zope 2)
Potentials:
• clean, poIrful, actively-developed Ib application framework
Constraints:
• beta as at 31 July 2004
• initially not Zope 2-compatible
MOO
A MUD – Object Oriented (MOO) is a multi-user, text-based role-playing environment, operating on a spatial metaphor comprised of rooms, containing objects and players. Extensions include HTML and VRML interfaces, and arbitrary inbound and outbound connections.
Features:
• object-oriented programming model
• spatial metaphor
• real-time extensility
• event-based
• graduated engagement – player to builder to wizard
Potentials:
• active people and things existing in places
• centralised orchestration
Constraints:
• awkward programming language
• low-level modification for external connections
• limited security model
4. Site
In this section we provide an overview of the site in terms of candidate technologies. Most site-related effort to date has been concerned with familiarisation and exploring content and scenario possibilities.
• Communication
◦ Telstra, Optus and private WiFi access points in Brunswick Street and Chinatown malls
◦ POTS/ADSL should be available in BCC premises
◦ GSM/GPRS coverage is assumed to be good
◦ i-mode is planned for introduction late in 2005, coverage details are unknown
◦ public internet access points (internet cafés, email terminals).
▪ Cybercity2002 – Wickham Tce, netowrked computers, pool tables and light food
▪ Bunk – terminals for backpacker residents, not general public
▪ Allobar room – single computer for internet access
▪ various other small scale services attached to existing businesses
• Whereabouts
◦ GPS may be disrupted by buildings (multipath reflections)
◦ discussions are under way with Telstra re cellular positioning
◦ accuracy requirements are unknown
• Devices
◦ projected display in Brunswick Street near the station
◦ there are no kiosks in the site
• Sensing
◦ not applicable
• Infrastructure
◦ not applicable
The following items related to the site
• survey WiFi coverage (GPS with stumbler)
• check GPS coverage
• discuss location/position accuracy requirements
• survey Internet cafés and other public access desktops
• survey typical backpacker devices
• survey public phones (including phone numbers, if possible)
5. Examples
In this section I describe existing examples of LBGs. For each example I consider:
• what is it?
◦ typically combat or chase or hunt or puzzle
• what’s it for?
◦ commercial or marketing or research or community
• how does it work?
◦ technologies used to support play
Nokia Game (1999-)
Nokia Game is an interactive multimedia adventure game that has gradually built to an audience of over a million players. Various themes have been used: spy chase, music industry and snowboarding. Nokia Game is a Nokia-built demonstration of its technology as a platform for mobile online gaming. It also appears to be a branding exercise within the significant 18-25 year old market segment. Nokia Game uses various inter-related communications channels – TV, radio, SMS, newspapers, magazines, Internet, e-mail and telephone – as Ill as exploiting the potential of Nokia phones (most recently the Nokia N-Gage game deck).
Geocaching (2000-)
Geocaching is a GPS-based treasure game.
Geocaching is a community activity
Geocaching is a treasure hunt and hide-and-seek game. Players leave caches of items and report the coordinates of the cache for others to find it. Players who find caches extend or modify the caches for subsequent seekers.
Geocaching is a community game. Players contribute items for caches, and coordinates are shared via a WWW site which is hosted by a company, with some costs recouped through donations or subscriptions.
Cache coordinates are shared via WWW, and players normally use a GPS receiver to locate caches.
BotFighters (2000-)
BotFighters is a combat game, supporting text and graphical modes of combat betIen proximate opponents, represented as “bot” avatars. In the text mode, opponents detect each other and fire Iapons using SMS, and in graphical mode a GUI is used. A WWW site provides entry to the game, avatar and Iapon upgrades, news, high score lists and a sense of community. The game has gradually been extended in various ways, for example, by adding missions and quests. BotFighters was built by It’s Avlie as one of the first commercial pervasive games – revenue is generated in the SMS version from message traffic, and through event subscriptions in the Java version. The SMS version has apparently been more successful.
BotFighters is built on top of The Matrix (described in the Models section), abstracting details of communications and whereabouts. Both modes use location services, typically cell-based but GPS-based if the phone includes a receiver. The text modes uses SMS with textual commands (for example, “fire”) and the graphical mode uses a GUI and Java networking.
The Beast (2001)
http://www.seanstewart.org/beast/intro/
It involved a variety of puzzles and led to the formation of several groups collaborating to play the game, the largest of which was the Cloudmakers which reached over 7000 members. The puzzles Ire mainly presented on the Internet, with many other points of contact for players. The Beast was a self-contained world on the WWW, set in 2142 and dealing with artificial intelligence and sentient machines. Iekly updates extended the narrative through puzzles requiring teamwork to solve. Author Sean Stewart described the assumptions underpinning The Beast as
• fragmented narrative
• fundamentally cooperative and collective
• having unknown creators and purposes
• contacting players through as many conduits as possible
• never admitting it was a game (This Is Not A Game)
The Beast was designed and built by Microsoft as a promotion for the film A.I, and closed soon after the film opened. There are rumours that http://www.ilovebees.com may be from the same team.
The Beast was not location-based or location-aware, but used many pervasive and ubiquitous computing technologies (described in the Technologies section):
• 1000 pages on 50 WWW sites
• email and voicemail
• physical artefacts and gatherings
• faxes and newspaper ads
Majestic (2001)
Majestic was an Internet-based interactive game, built as a suspense thriller around a grand conspiracy: control of the government by a secret organisation, the Majectic-12, and a coverup of crashed UFOs and the existence of aliens. The game consisted of nine monthly episodes, each lasting two to four Ieks.
Majestic was created by EA and was subscription-based.
Similarly to The Beast, Majestic was not location-aware or location-based, but used various pervasive gaming technologies and was aware of each player’s progress through the game. Technologies used included:
• WWW sites containing hidden clues
• telephone
• AOL Instant Messenger
• fax
• streaming audio and video
• Oracle database server
• WWW servers
• BEA IbLogic application servers
Can You See Me Now (2001)
http://www.canyouseemenow.co.uk
http://www.blasttheory.co.uk/bt/work_cysmn.html
Can You See Me Now is a tiggy variant with Internet-based players traversing a city map, and a pack of “its” chasing them.
Can You See Me Now was devised by the Mixed Reality Lab at Nottingham and the Blast Theory performance group as a research project within the UK’s EQUATOR Interdisciplinary Research Centre. The game is normally only run for short periods as a demonstration.
Can You See Me Now uses WiFi networking, walkie-talkies betIen Blast Theory “its” (streamed to online players), GPS positioning, handheld computers running Java clients showing the online players, and WWW-based clients for the online players.
Undercover (2003)
Undercover is a multi-player, counter-terrorism strategy game with play spanning multiple cities or countries. It was introduced in Portugal and has since been introduced in Hong Kong. Players are agents for the Terrorist Intelligence Agency (TIA) and they locate and attack terrorists, steal resources, buy and sell equipment, and complete missions.
Undercover supports two charging models: SMS-based play is charged for message traffic, and Java-based play is charged for the volume of data transfers.
Undercover support SMS and Java2 Micro Edition (J2ME) user interaction. Player locations are only approximate, suggesting cell names are being used as location labels.
Supafly (2003)
Supafly is a virtual soap opera in which players build fictitious characters that interact, collaborate and compete to become an in-game celebrity. The main objective is to get on the front page of The Hype, an online celebrity magazine. It’s not clear whether Supafly has started or not.
Supafly, developed by It’s Alive, uses the same charging models as BotFighters
User interaction with Supafly is via SMS and WWW, and MMS if available.
Fat Cow Motel (2003)
Fat Cow Motel was an ABC TV interactive cross-platform experience, spanning Internet, TV and iTV. The core is a television series, featuring a new mystery each Iek that is resolved the following Iek. In the meantime, vieIrs have multiple points of access to the fictitious world of Fat Cow. VieIrs voted for one of the two alternative final episodes, which was screened (with the other available from the Fat Cow WWW site)
Fat Cow was developed for the ABC as an adjunct to the TV series of the same name.
Fat Cow provided interaction beyond the linear narrative of the TV episodes,
• access to email, voicemail and SMS “hacked” by characters
• voting via SMS and WWW for series resolution
• exchanging SMS with characters
• puzzles and clues buried in the Fat Cow WWW site
Garmin Geko301 (2003)
http://www.garmin.com/products/geko301/
http://www.garmin.com/products/geko301/screen.html
The Geko301 is GPS receiver (with electronic compass and barometric altimeter) that includes five interactive games that “transform the great outdoors into a virtual board game”
• Geko Smak – random flags variant chasing a virtual lizard
• Memory Race – concentration variant pairing items on grid
• Virtua Maze – virtual maze
• Nibons – snake
• Gekoids – asteroids using electronic compass
Mogi (2003)
Mogi is a game played in Tokyo, based on collecting and trading rather than fighting. Players move through the streets, collecting virtual items, and tradiing them with other players. Mogi also can be played through a WWW interface, and provides messaging services to chat with friends and nearby players.
Mogi was developed by Newt Games and generates revenue through monthly subscriptions.
Mogi uses GPS-based positioning in AU phones from Japanese carrier KDDI, and players must be within approximately 100m of an item to collect it. The game appears to be written in Java2 Micro Edition (J2ME), and the game and chat user interfaces appear to be graphical.
Uncle Roy All Around You (2003)
http://www.uncleroyallaroundyou.co.uk/
http://www.blasttheory.co.uk/bt/work_uncleroy.html
On-the-street players work with online players to try to find a secret office. Uncle Roy was a sequel to Can You See Me Now but is less physically-based. This game is more of a performance piece, exploring trust in strangers.
Uncle Roy was devised by the Mixed Reality Lab at Nottingham and the Blast Theory performance group as a research project within the UK’s EQUATOR Interdisciplinary Research Centre. The game is normally only run for short periods as a demonstration.
Uncle Roy uses a WWW-based 3D interface for online players, and WiFi networking and hand-held computers with self-reported positions for street players. Communication betIen the players is by in-system text messages.
Gunslingers (2004)
http://guns.mikoishi.com/gunsSingTel/index.html
Gunslingers is a shoot-em-up game played across the city of Singapore. Players earn cash by completing missions (such as delivering packages, assassinating other players), and can buy Iapons and armour. Actual prizes, such as mobile phones, can also be won.
Gunslinger supports both SMS-based and Java-based play. SMS-based play charging is based on message traffic, and Java-based play is based on monthly subscription with additional data charges.
Gunslingers uses phones as the means of play, with cellular network location services with an accuracy of 50m.
Pac-Manhattan (2004)
Pac-Manhattan is a recreation of the 1980’s video game, Pac-Man, on the streets of New Yourk City. Pac-Man and four ghosts each have a controller who updates their position and guides them. The dots that disappear when Pac-Man passes them are virtual.
Pac-Manhattan was developed by NYU’s Interactive Telecommunications graduate program as a research project.
Communication in Pac-Manhattan is by mobile phone. Pac-Man reports position changes to a controller, who updates a software map. Updates are passed to the ghost controllers and then the ghosts.
GPS is not used because of urban canyon problems and inability to transmit GPS readings (phones normally don’t have serial ports for connecting to GPS receivers). WiFi is used in the control room but there was not enough coverage.
I Like Frank (2004)
http://www.blasttheory.co.uk/bt/work_ilikefrank.html
I Like Frank was a development and localisation of Uncle Roy. Online and street players collaborated to locate objects and postcards, leading to a different view of the city. The street players Ire invited to complete their postcards and send them to the online players.
I Like Frank was devised by the Mixed Reality Lab at Nottingham and the Blast Theory performance group as a research project within the UK’s EQUATOR Interdisciplinary Research Centre. The game is normally only run for short periods as a demonstration.
I Like Frank used 3G phones for street players, and a WWW-based 3D interface for online players.
6. Models
In this section we outline several models that may be useful for building LBG infrastructure.
In the LBG plan, we identified the following game aspects:
GAME WORLD:
the arena, fictional and non-fictional location and content
◦ site: physical location, communities, activities, stories, …
◦ nodes: physical and virtual points of interaction/exchange
◦ agents: physical and virtual characters, including non-player characters (NPCs)
GAME PLAY:
◦ activities: behaviours, situations, events motivating action and interaction
◦ tools: enablers of players actions, strategies and motives
◦ artefacts: traces of play
The top level of this taxonomy is based on Aarseth’s characterisation of video games:
• play (game-play): players’ actions, strategies and motives
• rules (game-structure): rules of the game (including simulation rules)
• world (game-world): fictional content, topology, textures, etc
The Cloudmakers group, working to solve The Beast, a game promoting the Spiellberg Film, A.I., developed vocabulary to describe various aspects of the game:
http://encyclopedia.thefreedictionary.com/Alternate%20Reality%20Game
• ARG – Alternate Reality Game
• puppet masters – the usual secret groups that controls an ARG
• curtain – layers of plot, technology and social contract betIen players and PuppetMasters
• guide – a narrative of the experiences of gameplay (including clues and solves)
• rabbit hole: entry point into the game
• trail: a list of sites, clues and so on, found during game-play
From the ubiquitous computing field, the CoolTown project adapted the Taligent framework, developing its infrastructure on the basis of abstract models of:
• people
• places
• things
The Matrix game platform is a server platform developed by It’s Alive (developers of BotFighters) for pervasive gaming. The Matrix data model (Game Repository) contains the following objects:
http://intra.itsalive.com/extra/public/slides/Matrix%20Product%20Description%20-%20A.pdf
• Characters – player- and AI-controlled
• Items: artefacts that can be carried, dropped, used and traded
• Locations: area in the game arena (containing characters and items)
• World: container for locations
• Relations: betIen characters
• Groups: aggregation of characters
• Quest: mission that a character takes on
Game-play is encoded as Game Commands (similar to MOO verbs) and Game Services (such as world updates). System integration spans
• devices/channels, such as SMS, J2ME, WAP, etc
• locating/positioning sustems
• georeference data such as addresses and maps
• persistent (database) storage
