%PDF-1.2 %âãÏÓ 10 0 obj << /Length 11 0 R >> stream 0.25 w 2 J BT /F1 14 Tf 225.125 754.75 TD 0 Tc 0 Tw (Writing for video games)Tj ET BT /F2 10 Tf 173.125 725.75 TD (Viviane Gal, C\216cile Le Prado, St\216phane Natkin, Liliana Vega.)Tj ET BT /F2 9 Tf 265.125 712.75 TD (CEDRIC/ CNAM)Tj ET BT 227.375 700 TD ({gal, leprado, natkin, lvega} @cnam.fr)Tj ET BT /F3 10 Tf 99.375 675.75 TD 0.472 Tw (Abstract. This paper is a survey of the process and technology used for video games and tackles)Tj ET BT 99.375 664.25 TD 0.268 Tw (the problem of writing them. The first part of the paper addresses the general state of the art in the)Tj ET BT 99.375 652.75 TD 0.235 Tw (design of video games : market and technology constraints, production process. The second part is)Tj ET BT 99.375 641.25 TD 13.306 Tw (devoted to the writing of games practices and technology constraints.)Tj ET BT /F1 12 Tf 71.125 610.75 TD 0 Tw (1 Rationales)Tj ET BT /F2 10 Tf 71.125 582 TD 0.135 Tw (In 1999 the CNAM $Conservatoire National des Arts et M\216tiers$, the Universities of La Rochelle and Poitiers, in)Tj ET BT 71.125 567.75 TD 0.21 Tw (collaboration with IRCAM $Institut de Recherche et Coordination Acoustique/Musique$ and the CNBDI $Centre)Tj ET BT 71.125 553.75 TD 1.493 Tw (National de la Bande Dessin\216e et de l\325Image$ decided to create a new postgraduate training in video games)Tj ET BT 71.125 539.5 TD 3.304 Tw (design and development. To define the contents of this training, the authors of this paper interviewed)Tj ET BT 71.125 525.25 TD 1.751 Tw (representative of all the main activities involved in the game industry. This work has been completed by a)Tj ET BT 71.125 511.25 TD 1.25 Tw (bibliography analysis. This paper is a survey of the result of this work and in particular in the field of game)Tj ET BT 71.125 497 TD 1.015 Tw (design. To understand the specific features of game design in video games, it is necessary to presents general)Tj ET BT 71.125 482.75 TD 0.17 Tw (aspects of the game industry process and technology. The first section of this paper is devoted to this subject. In)Tj ET BT 71.125 468.75 TD 0.468 Tw (the second part we focused the presentation on game design. The last section discusses tools used to implement)Tj ET BT 71.125 454.5 TD 0 Tw (games.)Tj ET BT /F1 12 Tf 71.125 423.75 TD (2 Game industry state of the art)Tj ET BT /F1 10 Tf 71.125 397.25 TD (2.1)Tj 28.75 0 TD (A few words about the game industry)Tj ET BT /F2 10 Tf 71.125 365.75 TD 0.749 Tw (The computer game industry is one of the most important fields of the interactive multimedia industry. A 21.1)Tj ET BT 71.125 351.75 TD 1.426 Tw (Millions $ revenue is forecasted in 2003 [1]. The market is split between PC and console games $PS, PS2,)Tj ET BT 71.125 337.5 TD 0.804 Tw (Xbox, GameCube\311$ with two special cases : game for small console $Gameboy, Palm.$ and Online persistent)Tj ET BT 71.125 323.25 TD 0 Tw (games $like Everquest$, which are sold on a subscription basis.)Tj ET BT 71.125 295 TD 0.64 Tw (In the last twenty years game editors and distributors were generally also producing most of their products and)Tj ET BT 71.125 280.75 TD 1.256 Tw (developing the software tools used for games. There is an increasing trend to separate, like in more classical)Tj ET BT 71.125 266.75 TD 0 Tw (audio visual fields, these three domains into editing company, studio and specialized software editors.)Tj ET BT 71.125 238.25 TD 2.152 Tw (Console manufacturers are the great winners of the game industry: each time a console game is sold, the)Tj ET BT 71.125 224.25 TD 0 Tw (manufacturer gets royalties. Moreover the console manufacturer controls the game design and development.)Tj ET BT /F1 10 Tf 71.125 198 TD (2.2 Genre)Tj ET BT /F2 10 Tf 71.125 166.75 TD 1.931 Tw (What is a computer game? There are numerous answers to this question. In the purpose of this paper, we)Tj ET BT 71.125 152.5 TD 0.094 Tw (consider the word game from its classical meaning. As a consequence playing with computer games is mainly an)Tj ET BT 71.125 138.5 TD 0.968 Tw (entertainment, and the main goal of a game designer is to give fun to his public. This definition excludes, for)Tj ET BT 71.125 124.25 TD 0 Tw (example, computer education systems that may include some games as an artifact to teach.)Tj ET BT 71.125 96 TD 0.569 Tw (Game writing style is related to the genre of the games considered. Numerous possible classifications of games)Tj ET BT 71.125 81.75 TD 0 Tw (according to various criteria have been proposed in the literature. In this paper we will derive our taxonomy from)Tj ET endstream endobj 11 0 obj 4547 endobj 4 0 obj << /Type /Page /Parent 5 0 R /Resources <> /ProcSet 2 0 R >> /Contents 10 0 R >> endobj 16 0 obj << /Length 17 0 R >> stream 0.25 w BT /F2 10 Tf 71.125 759.75 TD 0 Tc 0.258 Tw (the one of Rollins [2]. This classification relies on the main focus of the game. It is not the most widely used $in)Tj ET BT 71.125 745.5 TD 0 Tw (particular, it is not used by the games press$, but it is rather clear and relates to the notion of genre in literature:)Tj ET BT /F4 10 Tf 71.125 717.25 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F1 10 Tf 13.4 0 TD (Action games)Tj /F2 10 Tf 57.825 0 TD 0.335 Tw ( lead the player to push as fast as possible \210 lot of frantic buttons. Fighting games $Beat them)Tj ET BT 89.125 703 TD 0 Tw (all$ are a good example of this genre.)Tj ET BT /F4 10 Tf 71.125 688.75 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F1 10 Tf 13.4 0 TD (Adventure games)Tj /F2 10 Tf 75.75 0 TD 0.847 Tw ( are probably the ones which are the most related to classical audiovisual scenario. The)Tj ET BT 89.125 674.75 TD 0 Tw (player is the hero$in$ of a complex scenario. Metal Gear Solid 2 is a typical adventure game.)Tj ET BT /F4 10 Tf 71.125 660.5 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD 0.271 Tw (The main features of )Tj /F1 10 Tf 86.75 0 TD 0 Tw (Strategy games)Tj /F2 10 Tf 65.53 0 TD 0.271 Tw ( are the complexity of the decisions taken by the player in a simulated)Tj ET BT 89.125 646.25 TD 1.909 Tw (or fantastic politic, economic or military universe. The Sims and Black and White are very elaborated)Tj ET BT 89.125 632.25 TD 0 Tw (strategy games.)Tj ET BT /F4 10 Tf 71.125 618 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F1 10 Tf 13.4 0 TD 1.401 Tw (Simulation games)Tj /F2 10 Tf 77.241 0 TD ( lead the player to exercise himself on simulated sport or physical device $Plane, car,)Tj ET BT 89.125 603.75 TD 0 Tw (skateboard\311$.)Tj ET BT /F4 10 Tf 71.125 589.75 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD 0.904 Tw (The aim of )Tj /F1 10 Tf 48.75 0 TD 0 Tw (Puzzle games)Tj /F2 10 Tf 58 0 TD 0.904 Tw ( is to solve a hard analytic challenge. The computer versions of classical games)Tj ET BT 89.125 575.5 TD 2.506 Tw ($like chess$ are the basis of Puzzle games. But Puzzle games lead the player to be in charge of an)Tj ET BT 89.125 561.25 TD 0 Tw (investigation. Myst games are an example of the genre.)Tj ET BT /F4 10 Tf 71.125 547.25 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD 0.531 Tw (The main goal of )Tj /F1 10 Tf 73.212 0 TD 0 Tw (Discovery games)Tj /F2 10 Tf 71.898 0 TD 0.507 Tw ( is to discover an historical, geographical\311 problematic embedded in a)Tj ET BT 89.125 533 TD 0 Tw (game, which looks like one of the previous genre. Discovery games are the equivalent of documentary in the)Tj ET BT 89.125 519 TD 0.597 Tw (audiovisual field. For example, Versailles game leads the player to discover the life of the king Louis XIV)Tj ET BT 89.125 504.75 TD 0 Tw (through a puzzle game.)Tj ET BT 71.125 476.5 TD 0.586 Tw (According to Rollins we define the style as the way the game is executed. "Duke Nukem and Tomb Raider are)Tj ET BT 71.125 462.25 TD 0.211 Tw (both action/ adventure games, but their style make us perceive at different genre". RPG $Role Playing Games$ is)Tj ET BT 71.125 448 TD 0 Tw (a mix of action/ adventure/ Strategy games.)Tj ET BT /F1 10 Tf 71.125 422 TD (3.3 The process)Tj ET BT /F2 10 Tf 71.125 404.75 TD (The creation of a game is carried out in four stages:)Tj ET BT /F4 8 Tf 89.125 390.5 TD (\267)Tj /F5 8 Tf 3.5 0 TD ( )Tj /F2 10 Tf 14.5 0 TD (Specification and planning)Tj ET BT /F4 8 Tf 89.125 376.5 TD (\267)Tj /F5 8 Tf 3.5 0 TD ( )Tj /F2 10 Tf 14.5 0 TD (Pre production)Tj ET BT /F4 8 Tf 89.125 362.25 TD (\267)Tj /F5 8 Tf 3.5 0 TD ( )Tj /F2 10 Tf 14.5 0 TD (Development)Tj ET BT /F4 8 Tf 89.125 348 TD (\267)Tj /F5 8 Tf 3.5 0 TD ( )Tj /F2 10 Tf 14.5 0 TD (Validation and testing.)Tj ET BT 71.125 319.75 TD 1.033 Tw (The conception of a game starts with either an original idea proposed by a studio or a query submitted by an)Tj ET BT 71.125 305.5 TD 0.944 Tw (editor $design Tomb Raider 23 or a Donald Duck game$. In both cases the first document produced is a short)Tj ET BT 71.125 291.5 TD 0 Tw (description $the synopsis$ which includes:)Tj ET BT /F4 10 Tf 89.125 277.25 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD (The public focussed $hard core gamers\311$)Tj ET BT /F4 10 Tf 89.125 263 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD (The plat-forms $PS2, PC\311$)Tj ET BT /F4 10 Tf 89.125 249 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD (The genre $s$)Tj ET BT /F4 10 Tf 89.125 234.75 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD (References $game, books\311$)Tj ET BT /F4 10 Tf 89.125 220.5 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD (A first draft of the planning)Tj ET BT 71.125 192.25 TD 0.588 Tw (Starting from this document a studio will produce a specification that includes the main original features of the)Tj ET BT 71.125 178 TD 0.065 Tw (game and a cost evaluation. It may include also a first prototype of the game. At the end of this first specification)Tj ET BT 71.125 164 TD 0.688 Tw (phase $called for example Concepting in the Ubi Soft terminology$ a decision to carry on is taken. It is mainly)Tj ET BT 71.125 149.75 TD 0 Tw (based on marketing consideration.)Tj ET BT 71.125 121.5 TD 0.836 Tw (The pre-production phase is mainly devoted to the game design, the production of a significant prototype, and)Tj ET BT 71.125 107.25 TD 0 Tw (the refinement of cost and planning evaluation. A second carry on decision is taken at the end of this step.)Tj ET endstream endobj 17 0 obj 5530 endobj 12 0 obj << /Type /Page /Parent 5 0 R /Resources <> /ProcSet 2 0 R >> /Contents 16 0 R >> endobj 19 0 obj << /Length 20 0 R >> stream 0.25 w BT /F2 10 Tf 71.125 759.75 TD 0 Tc 0.453 Tw (The development phase includes the creation of all the elements of the game $images, sounds, video, programs$)Tj ET BT 71.125 745.5 TD 0 Tw (and their integration.)Tj ET BT 71.125 717.25 TD 0.728 Tw (The first step of the validation is a functional testing $Alpha tests$, which is an evaluation of the quality of the)Tj ET BT 71.125 703 TD 1.636 Tw (game $principles, gameplay, man machine interface, aesthetic qualities, and ability to respond to the market)Tj ET BT 71.125 688.75 TD 0.909 Tw (needs$. If this first validation is passed, the second step is a debugging process $Beta tests$ done by a specific)Tj ET BT 71.125 674.75 TD 0 Tw (team.)Tj ET BT 71.125 646.25 TD 1.592 Tw (All this process is performed as iterations between prototypes enhancement and evaluation. At any time the)Tj ET BT 71.125 632.25 TD 0 Tw (project can be aborted, in particular at the end of the Alpha tests, when the economical goals may not be reached.)Tj ET BT 71.125 603.75 TD 0.91 Tw (The whole process takes from six months $small Gameboy games$ to three years, and cost up to 1, 5 millions)Tj ET BT 71.125 589.75 TD 0 Tw (dollars.)Tj ET BT /F1 12 Tf 71.125 559 TD (3 Writing for games)Tj ET BT /F1 10 Tf 71.125 532.5 TD (3.1 Introduction)Tj ET BT /F2 10 Tf 71.125 515.25 TD 0.783 Tw (Writing for games is a rather difficult task. Of course it is an interactive composition and, as in other fields of)Tj ET BT 71.125 501 TD 0.681 Tw (open work, the author must leave a controlled freedom to the player. But, in the opposite of the art installation)Tj ET BT 71.125 487 TD 0 Tw (field or interactive music composition, marketing goals drives the game industry. Game is mainly entertainment,)Tj ET BT 71.125 472.75 TD 1.491 Tw (hence the player must solve non-trivial but not too complex problems, leading to a succession of goals in a)Tj ET BT 71.125 458.5 TD 0.478 Tw (reasonable amount of time. The player must feel in an open interactive world, but should be driven to the game)Tj ET BT 71.125 444.5 TD 0.197 Tw (solution. To solve this paradox the game industry has invented several techniques derived from game theory and)Tj ET BT 71.125 430.25 TD 0 Tw (object oriented specification, which are summarized in this section.)Tj ET BT /F1 10 Tf 71.125 404 TD (3.2 Game and level design)Tj ET BT /F2 10 Tf 71.125 372.75 TD 0.271 Tw (A game is first and foremost an imaginary universe. Then the first step of the game specification is to define the)Tj ET BT 71.125 358.5 TD 0.873 Tw (main aspects of this universe: Epoch and style, context of the game, goal to be reached, main types of objects)Tj ET BT 71.125 344.5 TD 0 Tw (involved, user perception of the game\311 This part of the game definition is called the game design.)Tj ET BT 71.125 316 TD (Next steps of the game specification are called levels design. A level of the game is a mix of a virtual space, a set)Tj ET BT 71.125 302 TD (of puzzle to be solved in this space and the main actions to be done by the player to reach a given goal.)Tj ET BT /F1 10 Tf 71.125 275.75 TD (3.3 Scenario)Tj ET BT /F2 10 Tf 71.125 244.5 TD 0.275 Tw (There is an open discussion in the world of game design about story telling and scenario. The notion of scenario)Tj ET BT 71.125 230.25 TD 0.277 Tw (comes from the movie world and is related in one hand to the idea of story telling and in the other to a sequence)Tj ET BT 71.125 216 TD 0.526 Tw ($and time driven$ of scenes. A game can not be only a scenario, as the player must always be the main actor of)Tj ET BT 71.125 202 TD 0.405 Tw (the scene. Rollins argue that a game designed as a story should better be developed as a movie. The importance)Tj ET BT 71.125 187.75 TD 0.203 Tw (of the scenario is related to the genre of the game. For example a scenario often drives adventure games when in)Tj ET BT 71.125 173.5 TD 1.318 Tw (action or simulation games the scenario is mainly a piece of the context. But there is always a scenario in a)Tj ET BT 71.125 159.5 TD 0.743 Tw (game. It may be reduced to a sequence of goals to be reached or a path, which must be followed. This is even)Tj ET BT 71.125 145.25 TD 0 Tw (true in a car game where during a race the player must follow the circuit.)Tj ET BT 71.125 117 TD 0.944 Tw (But, even in a given genre, the importance of the scenario depends on the style of the designer. Consider two)Tj ET BT 71.125 102.75 TD 0.185 Tw (action/adventure games: Tomb Raider and Metal Gear. In the first one the scenario is reduced to almost nothing.)Tj ET BT 71.125 88.5 TD 1.962 Tw (The story is anecdotic and the characters $in particular the heroin Lara Croft$ are as fat as the paper of a)Tj ET BT 71.125 74.5 TD 0.157 Tw (cigarette. Tom Raider is mainly an action game. Metal Gear is also an action game. But one of the implicit goals)Tj ET endstream endobj 20 0 obj 4833 endobj 18 0 obj << /Type /Page /Parent 5 0 R /Resources <> /ProcSet 2 0 R >> /Contents 19 0 R >> endobj 22 0 obj << /Length 23 0 R >> stream 0.25 w BT /F2 10 Tf 71.125 759.75 TD 0 Tc 1.894 Tw (of the game is to understand the complexity of the universe and story embedded in the game. Metal Gear)Tj ET BT 71.125 745.5 TD 1.257 Tw (includes long non-interactive animations $cinematics$, able to drive the player in this universe and define the)Tj ET BT 71.125 731.25 TD 0.186 Tw (milestones of the game. Moreover, in Metal Gear solid 2, the player is in the first part of the game a mythic hero)Tj ET BT 71.125 717.25 TD 1.513 Tw ($Solid Snake$. He becomes, in the second part of the game, a new "white beginner" character $Raven$. The)Tj ET BT 71.125 703 TD 2.629 Tw (designer, Ideo Kogima, explains, in the making off, that this choice allows the player to understand the)Tj ET BT 71.125 688.75 TD 0.227 Tw (complexity of Snake character, taking a third person point of view. In the same making off, Kogima says that he)Tj ET BT 71.125 674.75 TD 0 Tw (has always wanted to make movies\311)Tj ET BT 71.125 646.25 TD 0.34 Tw (It is out of the goals of this paper to take an aesthetic point of view on this discussion. In the sequel we define a)Tj ET BT 71.125 632.25 TD 0.584 Tw (scenario as a specification, which forces a partial, or total ordering in the game execution. It may be a classical)Tj ET BT 71.125 618 TD 0.393 Tw (description of a sequence of scenes. But, in general, the game design scenario is a description of the main game)Tj ET BT 71.125 603.75 TD 0.203 Tw (phases and the navigation between phases. The level design scenario is a positioning of objects in a maze and an)Tj ET BT 71.125 589.75 TD 0.59 Tw (associated puzzle to be solved. It induces a partially ordered set of actions that the player must perform to end)Tj ET BT 71.125 575.5 TD 0 Tw (the level.)Tj ET BT /F1 10 Tf 71.125 549.25 TD (3.4 Components of the game design)Tj ET BT /F2 10 Tf 71.125 518 TD (The main components of the Game Design are:)Tj ET BT /F4 10 Tf 89.125 504 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD (The context of the game $epoch, style, historical or mythical references$)Tj ET BT /F4 10 Tf 89.125 489.75 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD 1.022 Tw (The global scenario $Topology, global navigation graph, main characters, nature and hierarchy of the)Tj ET BT 107.125 475.5 TD 0 Tw (levels$)Tj ET BT /F4 10 Tf 89.125 461.5 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD 0.815 Tw (Main features of the game, that is to say what makes the game unique. Features must be classified as)Tj ET BT 107.125 447.25 TD 0 Tw (fundamental aspects of the design and chroma.)Tj ET BT /F4 10 Tf 89.125 433 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD (The principles of the gameplay : modalities, goals, rules, main strategic choices)Tj ET BT /F4 10 Tf 89.125 419 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD (The image and sounds charts $look and feel$)Tj ET BT /F4 10 Tf 89.125 404.75 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD (The ergonomic principles: Interface, game learning, saving and loading options\311)Tj ET BT /F4 10 Tf 89.125 390.5 TD (\267)Tj /F5 10 Tf 4.6 0 TD ( )Tj /F2 10 Tf 13.4 0 TD 0.485 Tw (The classes of objects in the game. The concept of object in the game design must be understood as in)Tj ET BT 107.125 376.5 TD 1.215 Tw (object oriented specifications. Classes of objects are defined by their names, properties and interface)Tj ET BT 107.125 362.25 TD 1.28 Tw (specified as the actions $methods$ which can be performed on an object. Classes can be constructed)Tj ET BT 107.125 348 TD 1.94 Tw (using $more or less formally$ heritage and polymorphism operators. Objects can be active: It may)Tj ET BT 107.125 334 TD 0 Tw (include an automaton, which is used to specify the autonomous life of the object.)Tj ET BT 71.125 305.5 TD (We will consider to opposite example: The Sims and Gran Turismo.)Tj ET BT 71.125 277.25 TD 0.422 Tw (Sim city, designed by Will Wright, started as a simulation based on the urban planning simulation derived from)Tj ET BT 71.125 263 TD 1.656 Tw (Jay Forrester system theory. W. Wright took the idea of architecture being a functional solution to life and)Tj ET BT 71.125 249 TD 0.859 Tw (coupled it with his fascination for 3D home architecture products. Objects in Sims are all the main things you)Tj ET BT 71.125 234.75 TD 0.614 Tw (can find in a life in a town: buildings, the people classified by sex and profession, the animals, the materials to)Tj ET BT 71.125 220.5 TD 1.863 Tw (built houses and monuments, TV sets, phones, birds\311. Each object is associated with all the main actions)Tj ET BT 71.125 206.5 TD 1.663 Tw ($methods$ which can be found in the real life. Make a phone call, buy a car, built a house, fall in love\311)Tj ET BT 71.125 192.25 TD 0.505 Tw (Ambient objects are used to define things like a changing weather or ambient sounds. Other objects are used as)Tj ET BT 71.125 178 TD 0.214 Tw (elements of the staging, for example virtual camera allowing several point of views of the same scene. The main)Tj ET BT 71.125 164 TD 1.059 Tw (features of the Sims are the variety and the number of actions that a player can do and the complexity of the)Tj ET BT 71.125 149.75 TD 0 Tw (embedded simulation model which take into account all theses actions.)Tj ET BT 71.125 121.5 TD 0.743 Tw (On the other hand consider a car racing game such as Gran Turismo 3, in this case, objects are the set of cars,)Tj ET BT 71.125 107.25 TD 1.445 Tw (that can be used as the elements of possible racing circuit. The main features on Gran Turismo are also the)Tj ET BT 71.125 93 TD 0.179 Tw (variety of choice allowed in the context of a car game $cars, circuits, kind of races\311$, the quality of the physical)Tj ET BT 71.125 79 TD 0 Tw (simulation and the real time graphics.)Tj ET endstream endobj 23 0 obj 5804 endobj 21 0 obj << /Type /Page /Parent 5 0 R /Resources <> /ProcSet 2 0 R >> /Contents 22 0 R >> endobj 25 0 obj << /Length 26 0 R >> stream 0.25 w BT /F2 10 Tf 71.125 745.5 TD 0 Tc 0.606 Tw (In both cases objects have numerous attributes: geometry and appearance, variable parameters $strength, speed,)Tj ET BT 71.125 731.25 TD 0 Tw (robustness$, type of actions allowed on the object $move right, jump, ring, explode\311$\311)Tj ET BT /F1 10 Tf 71.125 691 TD (3.5 Level Design)Tj ET BT /F2 10 Tf 71.125 659.75 TD 1.121 Tw (Generally the level is first defined by the geometry of the space: a given maze, a race circuit. Then the level)Tj ET BT 71.125 645.5 TD 1.03 Tw (designer chooses the positions and actions associated with the objects in this level. The goal is either implicit)Tj ET BT 71.125 631.25 TD 0.245 Tw ($win the game on this circuit$ or explicit $find three elements of a totem to open a gate$. In both cases the player)Tj ET BT 71.125 617.25 TD 0 Tw (is conduct by an implicit scenario, which limit the number of possible effective actions.)Tj ET BT 71.125 588.75 TD 0.137 Tw (To keep the sensation of freedom, several solutions are used: first, a set of independent actions can be performed)Tj ET BT 71.125 574.75 TD 0.487 Tw (in any order, in more complex games the player can pursue, in the same space, several goals in parallel. This is)Tj ET BT 71.125 560.5 TD 0.15 Tw (the case in Sims, where the player is able to take a lot of political and social decisions, but some message inform)Tj ET BT 71.125 546.25 TD 0.66 Tw (him, when the people or the city is going wrong as a consequence of these decisions. In the car game, you can)Tj ET BT 71.125 532.25 TD 0 Tw (drive, as you want as long as\311you follow the circuit until the end of the race!)Tj ET BT 71.125 504 TD 1.329 Tw (The puzzles and levels must be designed in a way such that the player doesn\325t feel trapped in a cycle. The)Tj ET BT 71.125 489.75 TD 1.284 Tw (degree of difficulty increases gradually. As a consequence levels are generally designed and developed in an)Tj ET BT 71.125 475.5 TD 0 Tw (increasing order of complexity.)Tj ET BT 71.125 447.25 TD 0.827 Tw (Cinematics are placed in between levels to present information needed at the next step, while the player relax,)Tj ET BT 71.125 433 TD 0 Tw (enjoys his accomplishments and recovers for the next challenge.)Tj ET BT /F1 10 Tf 71.125 407 TD (3.6 Immersion and Interactivity)Tj ET BT 71.125 375.5 TD (Introduction)Tj ET BT /F2 10 Tf 71.125 347.25 TD 0.428 Tw (The feeling of immersion either on a perceptual emotional or intellectual point of view is one of the key factors)Tj ET BT 71.125 333 TD 0 Tw (of a game:)Tj ET BT 127.125 319 TD ("To enter a game, I must be catch by, the image, the touch and finally the gameplay",)Tj ET BT 71.125 304.75 TD 0.253 Tw (explains Frederic Raynal, the game designer of Alone in the dark. Hence the "look and feel" is a main feature of)Tj ET BT 71.125 290.5 TD 0.207 Tw (the game. This is the art peace of the game, which is out of the scope of this paper. But the feeling of immersion)Tj ET BT 71.125 276.5 TD 0.146 Tw (and the technology constraints are fundamental element of the game design. In this section we discussed first the)Tj ET BT 71.125 262.25 TD 0.523 Tw (gameplay analysis. We consider then several important ergonomic factors: learning process, saving and loading)Tj ET BT 71.125 248 TD 0 Tw (options. At least, we point out some aspects of the peripherals.)Tj ET BT /F1 10 Tf 71.125 219.75 TD (Gameplay)Tj ET BT /F2 10 Tf 71.125 191.5 TD 1.221 Tw (A gameplay is first defined by a hierarchy of goals given to the player. Goals can be explicit: in GTA 3 the)Tj ET BT 71.125 177.25 TD 0.573 Tw (player is a gangster and he must perform a sequence of missions $kill somebody, destroy a bar\311$. In the game)Tj ET BT 71.125 163 TD 0.919 Tw (Black and White, the player is a God of a small world. His main goal is to be recognized and honored by his)Tj ET BT 71.125 149 TD 0.76 Tw (people. To reach this goal he can be a good God, helping people in their life or a kind of devil, known for his)Tj ET BT 71.125 134.75 TD 1.445 Tw (cruelty. This goal is implicit. The player discovers it when he understands that his power increases with the)Tj ET BT 71.125 120.5 TD 0.204 Tw (number of believers. But in the same game each level is defined by an explicit goal written on a message $help a)Tj ET BT 71.125 106.5 TD 1.998 Tw (shepherd to find his sheep$. To reach the goal the player must take some decisions that are the core of a)Tj ET BT 71.125 92.25 TD 0 Tw (gameplay.)Tj ET endstream endobj 26 0 obj 4454 endobj 24 0 obj << /Type /Page /Parent 5 0 R /Resources <> /ProcSet 2 0 R >> /Contents 25 0 R >> endobj 28 0 obj << /Length 29 0 R >> stream 0.25 w BT /F2 10 Tf 71.125 759.75 TD 0 Tc 2.185 Tw (Decisions are classified according to their long or short time effects $strategic or tactic$. The player must)Tj ET BT 71.125 745.5 TD 0.398 Tw (understand quickly $intuitively$ which decisions are inefficient. In counter part, a decision must not be trivial. It)Tj ET BT 71.125 731.25 TD 0.402 Tw (must have some positive aspects and some non predictable counter parts: Building a castle needs to spend some)Tj ET BT 71.125 717.25 TD 0.784 Tw (resources which may be useful in the sequel, choosing a devastating big gun may slowdown the player for the)Tj ET BT 71.125 703 TD 0 Tw (gun is heavy.)Tj ET BT 71.125 674.75 TD 0.186 Tw (This dominant strategy problem is well known in game theory. To avoid dominant strategy, the effect of choices)Tj ET BT 71.125 660.5 TD 0.368 Tw (must be non transitive. A classical example of this kind of choices is the paper/scissors/ stone game. Paper wins)Tj ET BT 71.125 646.25 TD 1.351 Tw (against stone, stone wins against scissors, and scissors wins against paper. A way to construct non-dominant)Tj ET BT 71.125 632.25 TD 1.542 Tw (strategy is to define decisions $made by the player and the computer$ as a vector of criteria. A decisions A)Tj ET BT 71.125 618 TD 1.249 Tw (dominates B, if the vector associated with A is, component by component, greater than the vector associated)Tj ET BT 71.125 603.75 TD 1.315 Tw (with B. Numerous games $in particular RPG games$ use explicitly this representation of decision. Numerous)Tj ET BT 71.125 589.75 TD 1.19 Tw (other simple ideas of game theory can be used to design a good gameplay $MinMax analysis, optimal mixed)Tj ET BT 71.125 575.5 TD 0 Tw (strategy, game tree.$.)Tj ET BT 71.125 547.25 TD 0.287 Tw (The other problem of gameplay is to allow the player to reach its goal in a fair and not too complex way. As the)Tj ET BT 71.125 533 TD 0.947 Tw (computer knows everything about the state of the universe, it can easily win in all situations. Moreover it can)Tj ET BT 71.125 519 TD 0.351 Tw (decide at any time that the game is over. This kind of gameplay will be perceived as unfair. The gameplay must)Tj ET BT 71.125 504.75 TD 0.239 Tw (be associated with a learning process: when the player loose, he must be able, from the information given by the)Tj ET BT 71.125 490.5 TD 0 Tw (game, to understand his mistakes.)Tj ET BT /F1 10 Tf 71.125 464.5 TD (Ergonomic principles and learning process)Tj ET BT /F2 10 Tf 71.125 447.25 TD 0.593 Tw (As almost all virtual reality system, a game is an implicit learning system. Understanding the laws of the game)Tj ET BT 71.125 433 TD 0.853 Tw (universe is a part of the fun. It must not be too simple to keep some mystery. Excessive information leads the)Tj ET BT 71.125 419 TD 0.789 Tw (player to feel guided. But the learning process must not be too complex to allow a discovery by practice. This)Tj ET BT 71.125 404.75 TD 1.021 Tw (has already been point out from the gameplay point of view, but it is also true from a man machine interface)Tj ET BT 71.125 390.5 TD 0 Tw (point of view.)Tj ET BT 71.125 376.5 TD 1.71 Tw (Each time a player executes an action, he is expecting something to happen as a consequence. Some game)Tj ET BT 71.125 362.25 TD 0.984 Tw (designers suggest that every interaction with the game system should have an answer [3]. Most of the player)Tj ET BT 71.125 348 TD 1.789 Tw (actions must have an influence in the game universe. In counter part, the consequence must not be always)Tj ET BT 71.125 334 TD 1.335 Tw (entirely revealed. But, as the learning process must be implicit, the consequence on an action must be logic.)Tj ET BT 71.125 319.75 TD 0.082 Tw (Hence all classical ergonomics principles of a computer interface $the same action lead to the same consequence,)Tj ET BT 71.125 305.5 TD 0 Tw (reflex actions must be intuitive,\311$ apply to games.)Tj ET BT 71.125 291.5 TD 0.322 Tw (When a player open a manual to understand a game, It can be considered as a failure of the design. The training)Tj ET BT 71.125 277.25 TD 0.522 Tw (must be an integrated part of the game and must not disturb the player too much from its feeling of immersion.)Tj ET BT 71.125 263 TD 0.473 Tw (Hence several levels of on line training are included in the game design. For all of them the goal is to teach the)Tj ET BT 71.125 249 TD 0.825 Tw (user how to interact with the game or give him additional information. Some of them, the more classical, use)Tj ET BT 71.125 234.75 TD 0.654 Tw (contextual menus, other might appear as icons or characters activated by certain actions and the latest ones use)Tj ET BT 71.125 220.5 TD 0.347 Tw (some kind of sound effects to interact with the user. For example in Black and White two little characters $good)Tj ET BT 71.125 206.5 TD 0.149 Tw (and bad consciences$ provides spoken contextual advice. There are also a lot of little notes written all around the)Tj ET BT 71.125 192.25 TD 0 Tw (scenery.)Tj ET BT 71.125 178 TD 0.953 Tw (The game and level design scenario define a second level of training. The first levels of the game are built to)Tj ET BT 71.125 164 TD 0.679 Tw (teach and introduce the player in the game. In contrast, they are also training spaces $isolated rooms, training)Tj ET BT 71.125 149.75 TD 0.568 Tw (islands, etc$ where the player can go at any time to exercises him self. In the same way, actions and simulation)Tj ET BT 71.125 135.5 TD 0.512 Tw (game provides also a particular playing training mode. It is a special purpose level where the goal of the player)Tj ET BT 71.125 121.5 TD 1.563 Tw (allows him and the game play to measure his abilities. The game execution can be altered according to the)Tj ET BT 71.125 107.25 TD 0 Tw (results of these training sessions.)Tj ET endstream endobj 29 0 obj 5772 endobj 27 0 obj << /Type /Page /Parent 5 0 R /Resources <> /ProcSet 2 0 R >> /Contents 28 0 R >> endobj 32 0 obj << /Length 33 0 R >> stream 0.25 w BT /F1 10 Tf 71.125 759.75 TD 0 Tc 0 Tw (Loading and saving options)Tj ET BT /F2 10 Tf 71.125 734 TD 1.312 Tw (As a consequence of the hardware architecture, in particular console architecture, all operations on persistent)Tj ET BT 71.125 719.75 TD 1.109 Tw (memory can slowdown the game. In order to keep the feeling of immersion several techniques are taken into)Tj ET BT 71.125 705.75 TD 0.61 Tw (account for saving, backups, loading, and the exchange of CD operations. CD exchange and saving options are)Tj ET BT 71.125 691.5 TD 0.623 Tw (mainly game play driven. Different politics are used: some games have \322choke point\323 which controls the game)Tj ET BT 71.125 677.25 TD 0.863 Tw (progression. To save the game the player must reach "physically" a choke point. Some choke points induce a)Tj ET BT 71.125 663.25 TD 0 Tw (commitment: data are saved and roll back before this point is not allowed. In present games, several choke points)Tj ET BT 71.125 649 TD 0.396 Tw (can be kept. In all cases all the work done between choke points is lost. This option is mainly due to the lack of)Tj ET BT 71.125 634.75 TD 1.496 Tw (space on WROM memories. Hence the state variables must have well defined values at saving points. As a)Tj ET BT 71.125 620.75 TD 0.604 Tw (consequence the time to save the game is small enough and the player includes his race to a choke point in the)Tj ET BT 71.125 606.5 TD 0 Tw (game challenge. On PC and Xbox games $that have a hard disk$ games may have more elaborated saving options)Tj ET BT 71.125 592.25 TD 1.59 Tw ($automatic or controlled saving at any time$. For example in the Sims the interface and saving menu offers)Tj ET BT 71.125 578.25 TD 0 Tw (several options. The player can save at any time and, as a consequence quit the game when he wants)Tj /F1 10 Tf 404.019 0 TD (.)Tj ET BT /F2 10 Tf 71.125 564 TD 0.887 Tw (For the same reasons there are no good solutions to the loading process on consoles like the PS2. The lack of)Tj ET BT 71.125 550 TD 0 Tw (memory and the bus characteristics induce a delay each time the player is moving from a scene to one other. This)Tj ET BT 71.125 535.75 TD 1.015 Tw (is unfortunately the case for action and adventure games evolving in a real time 3D world which descriptions)Tj ET BT 71.125 521.5 TD 0.32 Tw (include numerous textures. The loading delays are particularly disturbing for this king of games. In this case the)Tj ET BT 71.125 507.5 TD 0.475 Tw (game design play on the scenario $loading at still point of the story, at the end of a fight$ and a transition based)Tj ET BT 71.125 493.25 TD 0 Tw (on fixed images, environmental sounds and music.)Tj ET BT /F1 12 Tf 71.125 462.5 TD (4 Tools)Tj ET BT /F1 10 Tf 71.125 433.75 TD (4.1 Images, Sounds, Touch)Tj ET BT /F2 10 Tf 71.125 405.5 TD 0.699 Tw (Numerous manufacturers have developed low cost immersion peripherals $goggle, guns, steering wheels, guns,)Tj ET BT 71.125 391.25 TD 0.303 Tw (and elaborated paddle for PC, dancing carpet\311$. Out of Japan it has been generally a commercial failure. There)Tj ET BT 71.125 377 TD 0.571 Tw (are several reasons to this fact. First there is a lack of interface standardization. Hence a peripheral can be used)Tj ET BT 71.125 363 TD 0.453 Tw (only with one or two games. Even if it is relatively cheap such hardware cost a quarter or a third of the console)Tj ET BT 71.125 348.75 TD 0.956 Tw (price which is too expensive. The use of goggle and headphone is not adapted to play during hours, like hard)Tj ET BT 71.125 334.5 TD 0 Tw (core games do.)Tj ET BT 71.125 320.5 TD 0.135 Tw (From a visual and audio point of view the development of the home theater may change the situation, at least for)Tj ET BT 71.125 306.25 TD 1.157 Tw (console games. If a huge screen and a 5.1 audio system replace the TV set, the feeling of immersion will be)Tj ET BT 71.125 292 TD 0 Tw (greatly facilitated.)Tj ET BT 71.125 263.75 TD 0.082 Tw (In term of interface PC games sensors and actuators have a less privileged place than console games. Of course a)Tj ET BT 71.125 249.5 TD 0.155 Tw (PC can use a wide monitor, good and well-positioned HP's and a fine paddle. But the game must be designed for)Tj ET BT 71.125 235.5 TD 0.616 Tw (a PC with a 15 inch monitor, an old graphic accelerator and sounds card, one HP and a mouse. On console the)Tj ET BT 71.125 221.25 TD 0.237 Tw (interface is the TV set, the hardware architecture is determined so as the paddle. It is interesting to point out that)Tj ET BT 71.125 207 TD 0.146 Tw (console manufacturers lay down ergonomics rules related to the use of the paddle to the editors. Immersion must)Tj ET BT 71.125 193 TD 0 Tw (rely on subtle relationships between images, sounds and game play.)Tj ET BT 71.125 164.5 TD 2.173 Tw (Most of actions/adventure games developed for PC and the last generation of consoles used real time 3D)Tj ET BT 71.125 150.5 TD 0.226 Tw (animations $using several virtual cameras$. This is considered in a highly interactive or a scenario oriented game)Tj ET BT 71.125 136.25 TD 2.525 Tw (as an essential feature. This is the consequence of marketing constraints and a technical goal: the frame)Tj ET BT 71.125 122 TD 0.339 Tw (refreshment rate must be at least 30 frames/s. Whatever game you edit for a console, its manufacturer requires a)Tj ET BT 71.125 108 TD 0 Tw (frame rate up to 60 frames/s.)Tj ET BT 71.125 93.75 TD 0.437 Tw (The current generation of graphic accelerators can handle images composed with several thousands of polygons)Tj ET BT 71.125 79.5 TD 0.138 Tw (in the 60 frame/s throughput. Several millions of polygons are expected in the next generation. When a PC game)Tj ET endstream endobj 33 0 obj 5664 endobj 30 0 obj << /Type /Page /Parent 31 0 R /Resources <> /ProcSet 2 0 R >> /Contents 32 0 R >> endobj 35 0 obj << /Length 36 0 R >> stream 0.25 w BT /F2 10 Tf 71.125 759.75 TD 0 Tc 0.681 Tw (runs on a smaller configuration, game developers have adapted from VR technology scalability techniques: the)Tj ET BT 71.125 745.5 TD 0 Tw (game adapts the image definition according to the configuration. On strategy games 3D isometric view is still the)Tj ET BT 71.125 731.25 TD 1.075 Tw (main option, for it allows a simpler panoramic consideration of the situation. But this may evolve in the next)Tj ET BT 71.125 717.25 TD 0 Tw (years.)Tj ET BT 71.125 703 TD 1.298 Tw (3D sound is considered as an interesting ability to increase the feeling of immersion. 3D technology and the)Tj ET BT 71.125 688.75 TD 1.857 Tw (corresponding development tools are already available $EAX/EAGLE, Sensora Sound Engine, OpenAL and)Tj ET BT 71.125 674.75 TD 1.446 Tw (DirectX library$ for PC and the last generation of console. It has been successfully experimented on several)Tj ET BT 71.125 660.5 TD 0.103 Tw (games. The HP problem is the limiting factor to this trend. An other factor is the repartition of the CPU allocated)Tj ET BT 71.125 646.25 TD 0.599 Tw (to the different functions. Image synthesis is the most expensive function. This limits the audio, simulation and)Tj ET BT 71.125 632.25 TD 0 Tw (AI features that can be used.)Tj ET BT /F1 10 Tf 200.625 603 TD (Platform)Tj ET BT 256.125 603 TD (Graphics)Tj ET BT 311.875 603 TD (Sound)Tj ET BT 368.875 603 TD (IA)Tj ET BT 353.625 589 TD (and other)Tj ET 192.25 614.75 0.5 0.5 re f 192.25 614.75 0.5 0.5 re f 192.75 614.75 53.75 0.5 re f 246.5 614.75 0.5 0.5 re f 247 614.75 57.75 0.5 re f 304.75 614.75 0.5 0.5 re f 305.25 614.75 40 0.5 re f 345.25 614.75 0.5 0.5 re f 345.75 614.75 57 0.5 re f 402.75 614.75 0.5 0.5 re f 402.75 614.75 0.5 0.5 re f 192.25 586.5 0.5 28.25 re f 246.5 586.5 0.5 28.25 re f 304.75 586.5 0.5 28.25 re f 345.25 586.5 0.5 28.25 re f 402.75 586.5 0.5 28.25 re f BT /F2 10 Tf 196.125 574.25 TD (PC)Tj ET BT 196.125 560 TD ($game$)Tj ET BT 250.375 574.25 TD (60)Tj ET BT 308.625 574.25 TD (30)Tj ET BT 349.125 574.25 TD (10)Tj ET 192.25 586 0.5 0.5 re f 192.75 586 53.75 0.5 re f 246.5 586 0.5 0.5 re f 247 586 57.75 0.5 re f 304.75 586 0.5 0.5 re f 305.25 586 40 0.5 re f 345.25 586 0.5 0.5 re f 345.75 586 57 0.5 re f 402.75 586 0.5 0.5 re f 192.25 557.75 0.5 28.25 re f 246.5 557.75 0.5 28.25 re f 304.75 557.75 0.5 28.25 re f 345.25 557.75 0.5 28.25 re f 402.75 557.75 0.5 28.25 re f BT 196.125 545.5 TD (Console)Tj ET BT 250.375 545.5 TD (75)Tj ET BT 308.625 545.5 TD (15)Tj ET BT 349.125 545.5 TD (10)Tj ET 192.25 557 0.5 0.5 re f 192.75 557 53.75 0.5 re f 246.5 557 0.5 0.5 re f 247 557 57.75 0.5 re f 304.75 557 0.5 0.5 re f 305.25 557 40 0.5 re f 345.25 557 0.5 0.5 re f 345.75 557 57 0.5 re f 402.75 557 0.5 0.5 re f 192.25 542.75 0.5 14.25 re f 192.25 542.25 0.5 0.5 re f 192.25 542.25 0.5 0.5 re f 192.75 542.25 53.75 0.5 re f 246.5 542.75 0.5 14.25 re f 246.5 542.25 0.5 0.5 re f 247 542.25 57.75 0.5 re f 304.75 542.75 0.5 14.25 re f 304.75 542.25 0.5 0.5 re f 305.25 542.25 40 0.5 re f 345.25 542.75 0.5 14.25 re f 345.25 542.25 0.5 0.5 re f 345.75 542.25 57 0.5 re f 402.75 542.75 0.5 14.25 re f 402.75 542.25 0.5 0.5 re f 402.75 542.25 0.5 0.5 re f BT /F1 10 Tf 139.875 517 TD (Fig. 1)Tj /F2 10 Tf 23.887 0 TD ( Typical percentage of relative CPU consumption by functions in a game)Tj ET BT /F1 10 Tf 71.125 488.5 TD (4.2 Artificial Intelligence)Tj ET BT /F2 10 Tf 71.125 460.25 TD 0.998 Tw (Video games developers use to call "Artificial Intelligence" $AI$ any kind of techniques that gives the feeling)Tj ET BT 71.125 446 TD 0.289 Tw (that the computer is, as a player, not too stupid. A well-known example showing the lack of "AI" is the memory)Tj ET BT 71.125 432 TD 0.339 Tw (less behaviour of a soldier in one of the first versions of "Return to Castle Wolfenstein". When the player opens)Tj ET BT 71.125 417.75 TD 0.19 Tw (a door, he sees the back of an enemy and he can shoot him. But if he closes the door and then opens it twice, the)Tj ET BT 71.125 403.5 TD 0.356 Tw (enemy is still waiting to be killed. Hence the basic AI in games is to used memory variable and more generally)Tj ET BT 71.125 389.5 TD 0.453 Tw (to associate to each situation a finite automaton. More elaborates AI techniques are still used only in a minority)Tj ET BT 71.125 375.25 TD 0 Tw (of games. They are two reasons to this situation. First, as we have already point out, a low percentage of the CPU)Tj ET BT 71.125 361 TD 0.381 Tw (time is allocated to AI functions [8] [9]. This explanation of the poor level of AI is less and less justified [8], as)Tj ET BT 71.125 347 TD 0.618 Tw (the power of consoles is increasing quickly and as graphic accelerators can execute complex graphic functions.)Tj ET BT 71.125 332.75 TD 1.423 Tw (The second reason is related to the game play. Remember first that a computer playing does not need to be)Tj ET BT 71.125 318.5 TD 0.238 Tw (intelligent $that is to say able to react to any situation$, but has to look as intelligent. As all the game is designed)Tj ET BT 71.125 304.5 TD 0.192 Tw (to drive the player to the victory in a predictable time, situations can be predicted. The player may open the door)Tj ET BT 71.125 290.25 TD 0.658 Tw (behind the soldier once, twice at least three times, not more. An automaton with five or six possible states will)Tj ET BT 71.125 276 TD 0.1 Tw (give a sufficient feeling of intelligence. Moreover if a more sophisticated random algorithm is used to define the)Tj ET BT 71.125 262 TD 0 Tw (computer behaviour, it may become very difficult to control or to test.)Tj ET BT 71.125 233.5 TD 0.214 Tw (One may say that very efficient AI algorithms have been developed in the field of classical games $chess, go\311$.)Tj ET BT 71.125 219.5 TD 0.249 Tw (But the knowledge of chess game is the result of thousands of years of thinking. The state of the art in computer)Tj ET BT 71.125 205.25 TD 0.341 Tw (chess is the result of thirty years of research on a universally known game. Most of video games have a lifetime)Tj ET BT 71.125 191 TD 0.091 Tw (of six months. Each video game has its own rules, always rather simple. The difficulty of a game is generally not)Tj ET BT 71.125 177 TD 0 Tw (related to the rules, but to the ignorance of these rules by the player. [11] [12])Tj ET BT 71.125 148.5 TD 0.188 Tw (As stated before the main "AI" in game is the use of automaton or finite state machine. It is used, for example to)Tj ET BT 71.125 134.5 TD 0 Tw (control the enemies in first person shooter games $Doom like$.)Tj ET BT 71.125 106 TD (Standard graphs and relations algorithms, like R*, are used to simulates realistic movements and paths finding.)Tj ET endstream endobj 36 0 obj 6734 endobj 34 0 obj << /Type /Page /Parent 31 0 R /Resources <> /ProcSet 2 0 R >> /Contents 35 0 R >> endobj 38 0 obj << /Length 39 0 R >> stream 0.25 w BT /F2 10 Tf 71.125 759.75 TD 0 Tc 0.554 Tw (Random automata or fuzzy logic is used to avoid predictable or recurrent behaviour. The main use is to choose)Tj ET BT 71.125 745.5 TD 0.88 Tw (randomly between several strategies in a given situation. It can be combined with game theory mixed strategy)Tj ET BT 71.125 731.25 TD 0.889 Tw (point of view to built nice game play. This can be used in fight games $Beat them all$ and in action games in)Tj ET BT 71.125 717.25 TD 2.384 Tw (order to manage the behaviour of the enemies. The game Civilization, real time strategy game, uses this)Tj ET BT 71.125 703 TD 0.427 Tw (technique. It is also used in collective sport games to specify the variations around the collective behaviour of a)Tj ET BT 71.125 688.75 TD 0 Tw (team.)Tj ET BT 71.125 660.5 TD 0.856 Tw (The more elaborate games that use this classical point of view are strategic simulation games. The core of the)Tj ET BT 71.125 646.25 TD 1.623 Tw (gameplay is an event driven simulation model, which is a simplified version of a well-understood scientific)Tj ET BT 71.125 632.25 TD 1.646 Tw (simulation. The Sim City game was derived from works on urban simulations. Hence, even if the model is)Tj ET BT 71.125 618 TD 0 Tw (complex, it is always under control.)Tj ET BT 71.125 603.75 TD 0.637 Tw (Several military games, among them Conflict Zone by MASA group use a layered structure as AI architecture.)Tj ET BT 71.125 589.75 TD 1.831 Tw (Each layer corresponds to a level of decision $General, Captain, Troops$. They are most commonly named)Tj ET BT 71.125 575.5 TD 2.333 Tw (strategic, operational and tactical levels [9]. Decision priorities are ordered according to the levels. These)Tj ET BT 71.125 561.25 TD 0 Tw (complex genre of AI are derived from models developed for military applications.)Tj ET BT 71.125 547.25 TD (During the last years more sophisticated AI principles has been used :)Tj ET BT 71.125 519 TD 2.044 Tw (The artificial life allows splitting the specification of a complex global simulation into smaller ones. Each)Tj ET BT 71.125 504.75 TD 0.646 Tw ("object" of the game is specified as a random automaton sending and receiving stimuli from other objects. The)Tj ET BT 71.125 490.5 TD 0.899 Tw (global behaviour is the results of the interactions between local ones. The game "The Sims" implements these)Tj ET BT 71.125 476.5 TD 0.397 Tw (techniques. Artificial life is used to simulate phenomena such as the movements and behaviours of characters at)Tj ET BT 71.125 462.25 TD 0.396 Tw (home, in town, in holidays, ... Artificial life does not need more processing power than a global simulation, it is)Tj ET BT 71.125 448 TD 1.364 Tw (well suited for object oriented specification and distributed games. It has the same limitation than the global)Tj ET BT 71.125 434 TD 0 Tw (simulation technique : Only experimented artificial life model can be used in a commercial game.)Tj ET BT 71.125 405.5 TD 0.487 Tw (The neural networks can be used in order to update the AI model to take into account the player\325s progress and)Tj ET BT 71.125 391.5 TD 0.544 Tw (to adapt the difficulty to the player\325s style. The game rules seem to change continuously. "Fields of Battle" is a)Tj ET BT 71.125 377.25 TD 0 Tw (game that implements the neural network technique.)Tj ET BT 71.125 349 TD 0.417 Tw (Genetic algorithms $a part of evolutionary algorithms$ are the fashion in the video game world. It seems to be a)Tj ET BT 71.125 334.75 TD 0.454 Tw (promising way to create dynamically new types of objects $monster, weapons, sounds\311$ in the game. They are)Tj ET BT 71.125 320.5 TD 0.808 Tw (not used in practice. They are difficult to control $evaluation functions, mutation and cross over probabilities$)Tj ET BT 71.125 306.5 TD 0 Tw (and they still require too much processing power [8].)Tj ET BT /F1 10 Tf 71.125 264 TD (4.3 Architectures)Tj ET BT /F2 10 Tf 71.125 235.5 TD 1.176 Tw (Several companies $Infograme, Darkworks, Virtools\311$ have built a programming environment, which allows)Tj ET BT 71.125 221.5 TD 0.892 Tw (game development following the previous steps. Objects specified in the game design are implemented by the)Tj ET BT 71.125 207.25 TD 1.273 Tw (programmers and the team of graphic artists as classes in an object oriented library using all the facilities of)Tj ET BT 71.125 193 TD 2.138 Tw (object oriented programming $heritage, polymorphism\311$. The level designer defines the geometry using a)Tj ET BT 71.125 179 TD 1.115 Tw (standard 3D tool such as 3DSMax or Maya. A scripting language is then used to specify the level in term of)Tj ET BT 71.125 164.75 TD 0 Tw (objects in the space.)Tj ET BT /F6 10 Tf 71.125 150.5 TD 0.805 Tw (Virtools Dev 2.0)Tj /F2 10 Tf 67.25 0 TD ( offers a development environment for interactive applications. It has a graphic user interface)Tj ET BT 71.125 136.5 TD 1.267 Tw (where objects can be placed and manipulated easily. 3D objects are treated independent from their data and)Tj ET BT 71.125 122.25 TD 0.786 Tw (behavior. Other game creation systems are available in the market : )Tj /F6 10 Tf 280.759 0 TD (The Game Factory)Tj /F2 10 Tf 77.109 0 TD ( by Click Team, with a)Tj ET BT 71.125 108 TD 0.502 Tw (storyboard, a level and a event editor similar to the one in Director of Macromedia and )Tj /F6 10 Tf 363.5 0 TD (Pie 3D GCS)Tj /F2 10 Tf 50.443 0 TD ( by Pie in)Tj ET BT 71.125 94 TD 0 Tw (the Sky with a layout editor, a paint program and an engine to run the game.)Tj ET endstream endobj 39 0 obj 5502 endobj 37 0 obj << /Type /Page /Parent 31 0 R /Resources <> /ProcSet 2 0 R >> /Contents 38 0 R >> endobj 42 0 obj << /Length 43 0 R >> stream 0.25 w BT /F2 10 Tf 71.125 759.75 TD 0 Tc 0.678 Tw (The implementation of game relies generally on software called a game engine. A game engine is first a set of)Tj ET BT 71.125 745.5 TD 0.423 Tw (software libraries. Each library performs a set of functions needed to code the dynamic and interactive behavior)Tj ET BT 71.125 731.25 TD 0.827 Tw (of the game. General purpose game engine includes a 3D graphic engine used to code interactive animation, a)Tj ET BT 71.125 717.25 TD 0.388 Tw (sound engine which includes sound synthesis, effect and spatialization functions and more specific libraries like)Tj ET BT 71.125 703 TD 0.637 Tw (Artificial Intelligence engines used to code the gameplay and physic engines used to simulate physical systems)Tj ET BT 71.125 688.75 TD 0 Tw ($like cars for example$.)Tj ET BT /F1 10 Tf 140.625 659.5 TD (Architecture Levels)Tj ET BT 392.125 659.5 TD (Examples)Tj ET 67 671.25 0.75 0.75 re f 67 671.25 0.75 0.75 re f 67.75 671.25 229.5 0.75 re f 297.25 671.25 0.75 0.75 re f 298 671.25 229.5 0.75 re f 527.5 671.25 0.75 0.75 re f 527.5 671.25 0.75 0.75 re f 67 657 0.75 14.25 re f 297.25 657 0.75 14.25 re f 527.5 657 0.75 14.25 re f BT /F2 10 Tf 127.875 644.5 TD (Level design scripts editors)Tj ET BT 301.375 644.5 TD (God.move$right, 2$;Wait_Event;)Tj ET BT 301.375 630.5 TD (On button.click God_Anger:=new$thunder$)Tj ET BT 301.375 616.25 TD (God_Anger.lightning, God_Anger.sound)Tj ET 67 656.25 0.75 0.75 re f 67.75 656.25 229.5 0.75 re f 297.25 656.25 0.75 0.75 re f 298 656.25 229.5 0.75 re f 527.5 656.25 0.75 0.75 re f 67 613.75 0.75 42.5 re f 297.25 613.75 0.75 42.5 re f 527.5 613.75 0.75 42.5 re f BT 155.625 601.25 TD (Game classes)Tj ET BT 301.375 601.25 TD (class thunder)Tj ET BT 301.375 587.25 TD (methods: lightning , sound)Tj ET 67 613 0.75 0.75 re f 67.75 613 229.5 0.75 re f 297.25 613 0.75 0.75 re f 298 613 229.5 0.75 re f 527.5 613 0.75 0.75 re f 67 584.75 0.75 28.25 re f 297.25 584.75 0.75 28.25 re f 527.5 584.75 0.75 28.25 re f BT 75.625 572.25 TD (Game engine library: general purposes game oriented)Tj ET BT 166.375 558 TD (libraries)Tj ET 67 584 0.75 0.75 re f 67.75 584 229.5 0.75 re f 297.25 584 0.75 0.75 re f 298 584 229.5 0.75 re f 527.5 584 0.75 0.75 re f 67 555.75 0.75 28.25 re f 297.25 555.75 0.75 28.25 re f 527.5 555.75 0.75 28.25 re f BT 80.125 544 TD (Graphic)Tj ET BT 82.875 529.75 TD (engine)Tj ET BT 141.125 544 TD (Sound)Tj ET BT 140.375 529.75 TD (engine)Tj ET BT 198.125 544 TD (Physic)Tj ET BT 197.375 529.75 TD (Engine)Tj ET BT 263.875 544 TD (IA)Tj ET BT 255.625 529.75 TD (engine)Tj ET BT 301.375 544 TD (Create_new_object$God, god_geometry.vrml,)Tj ET BT 301.375 529.75 TD (god_texture.gif,god_voice.wav$)Tj ET 67 527.25 0.75 28.25 re f 124.5 527.25 0.75 28.25 re f 182.25 527.25 0.75 28.25 re f 239.75 527.25 0.75 28.25 re f 297.25 527.25 0.75 28.25 re f 527.5 527.25 0.75 28.25 re f BT 108.125 515 TD (General purpose multimedia libraries)Tj ET BT 114.625 500.75 TD ($Direct X, Open GL, Open AL\311$)Tj ET BT 301.375 515 TD (GlMatrixMode; alsourceplay$source1$)Tj ET 67 526.5 0.75 0.75 re f 67.75 526.5 56.75 0.75 re f 124.5 526.5 0.75 0.75 re f 125.25 526.5 57 0.75 re f 182.25 526.5 0.75 0.75 re f 183 526.5 56.75 0.75 re f 239.75 526.5 0.75 0.75 re f 240.5 526.5 56.75 0.75 re f 297.25 526.5 0.75 0.75 re f 298 526.5 229.5 0.75 re f 527.5 526.5 0.75 0.75 re f 67 498.25 0.75 28.25 re f 297.25 498.25 0.75 28.25 re f 527.5 498.25 0.75 28.25 re f BT 147.625 485.75 TD (Operating system)Tj ET BT 360.625 485.75 TD (Windows, PS2 Monitor\311)Tj ET 67 497.5 0.75 0.75 re f 67.75 497.5 229.5 0.75 re f 297.25 497.5 0.75 0.75 re f 298 497.5 229.5 0.75 re f 527.5 497.5 0.75 0.75 re f 67 483.25 0.75 14.25 re f 297.25 483.25 0.75 14.25 re f 527.5 483.25 0.75 14.25 re f BT 162.875 471 TD (Hardware)Tj ET 67 482.5 0.75 0.75 re f 67.75 482.5 229.5 0.75 re f 297.25 482.5 0.75 0.75 re f 298 482.5 229.5 0.75 re f 527.5 482.5 0.75 0.75 re f 67 468.25 0.75 14.25 re f 297.25 468.25 0.75 14.25 re f 527.5 468.25 0.75 14.25 re f BT 91.125 456 TD (Central)Tj ET BT 85.125 441.75 TD (Processor,)Tj ET BT 84.375 427.75 TD (memory\311)Tj ET BT 166.625 456 TD (Graphic)Tj ET BT 160.875 441.75 TD (accelerator)Tj ET BT 236.875 456 TD (Sound card)Tj ET BT 359.375 456 TD (PC, PS, GameCube, XBox)Tj ET 67 467.75 0.75 0.75 re f 143.75 467.75 0.75 0.75 re f 220.5 467.75 0.75 0.75 re f 297.25 467.75 0.75 0.75 re f 298 467.75 229.5 0.75 re f 527.5 467.75 0.75 0.75 re f 67 425.25 0.75 42.5 re f 67 424.5 0.75 0.75 re f 67 424.5 0.75 0.75 re f 67.75 424.5 76 0.75 re f 143.75 425.25 0.75 42.5 re f 143.75 424.5 0.75 0.75 re f 144.5 424.5 76 0.75 re f 220.5 425.25 0.75 42.5 re f 220.5 424.5 0.75 0.75 re f 221.25 424.5 76 0.75 re f 297.25 425.25 0.75 42.5 re f 297.25 424.5 0.75 0.75 re f 298 424.5 229.5 0.75 re f 527.5 425.25 0.75 42.5 re f 527.5 424.5 0.75 0.75 re f 527.5 424.5 0.75 0.75 re f BT /F1 10 Tf 219.125 398.75 TD (Fig. 2)Tj /F2 10 Tf 23.887 0 TD (: Software architecture for games)Tj ET BT 70.875 356.25 TD 0.548 Tw (When a collection of game relies on the same universe $Ubi Soft Ray Man games, for example$, the studio can)Tj ET BT 70.875 342.25 TD 0 Tw (define a specific game engine at the game classes level.)Tj ET BT 70.875 328 TD ( In several game engines there is also a software monitor, defined by the level design script, which schedules)Tj 0 -14.25 TD 0.197 Tw (either on a synchronous mode or asynchronous mode. On console platform the synchronous monitor approach is)Tj ET BT 70.875 299.75 TD 0.245 Tw (almost always used. On PC $as Windows 95,98\311 are highly asynchronous operating systems$ the asynchronous)Tj ET BT 70.875 285.5 TD 0 Tw (approach is possible.)Tj ET BT 70.875 271.25 TD ( The use of portable game engines)Tj /F2 6 Tf 139.5 4 TD (1)Tj /F2 10 Tf 3 -4 TD ( allows minimizing the work to be done to create multi platform games. The)Tj -142.5 -14 TD 2.443 Tw (Criterion engine)Tj /F2 6 Tf 67.75 4 TD (2)Tj /F2 10 Tf 3 -4 TD ( is a typical example of game engine. It contains a 3D Graphic engine, a sound engine)Tj ET BT 70.875 243 TD 1.433 Tw (originated from Sensora, a Physic engine originated from Karma and an IA engine. A game developed with)Tj ET BT 70.875 228.75 TD 1.068 Tw (Criterion game engine can be, in principle, ported on PC, Xbox and PS2 consoles. In practice the differences)Tj ET BT 70.875 214.75 TD 0 Tw (between the plat-forms hardware induce to adapt or even to change, in certain cases, the design of games.)Tj ET BT /F3 10 Tf 70.875 96.5 TD ( )Tj ET 70.75 98.5 144 0.5 re f BT /F3 6.5 Tf 70.875 89.5 TD (1)Tj /F3 10 Tf 3.25 -4.5 TD ( http:// 3dgraphics.about.com/cs/gameengines/)Tj ET BT /F3 6.5 Tf 70.875 78 TD (2)Tj /F3 10 Tf 3.25 -4.5 TD ( )Tj 0 0 1 rg 0 0 1 RG 2.5 0 TD (http://www.renderware.com/)Tj ET 76.5 72 115.5 0.5 re f endstream endobj 43 0 obj 6941 endobj 41 0 obj << /Type /Page /Parent 31 0 R /Resources <> /ProcSet 2 0 R >> /Contents 42 0 R >> endobj 45 0 obj << /Length 46 0 R >> stream 0.25 w BT /F1 12 Tf 70.875 743.25 TD 0 Tc 0 Tw (6 Conclusion)Tj ET BT /F2 10 Tf 70.875 714.5 TD 0.124 Tw (There is a process used for writing games, which seems to come out from our analysis of the present practices. It)Tj ET BT 70.875 700.25 TD 0.993 Tw (relies on an object oriented game design and a scenario oriented level design. We think that it is important to)Tj ET BT 70.875 686 TD 2.085 Tw (better understand and formalize this process. This could lead first to an analysis method for games, to be)Tj ET BT 70.875 672 TD 0.809 Tw (compared to the scenario analysis techniques used in movies. From a training and critical point of view this is)Tj ET BT 70.875 657.75 TD 0 Tw (fundamental.)Tj ET BT 70.875 643.5 TD 1.35 Tw (From a more technical point of view there is a lack of integrated writing tools, taken into account the game)Tj ET BT 70.875 629.5 TD 0.671 Tw (design step. We think that methods and tools used in object oriented design may be adapted to this goal. UML)Tj ET BT 70.875 615.25 TD 0.772 Tw ($unified method language$ method and tools are good candidates. Work in similar fields $behavioral scenario$)Tj ET BT 70.875 601 TD 0.441 Tw (has been already carried out)Tj /F2 6 Tf 114 4 TD (3)Tj /F2 10 Tf 3 -4 TD (.The objects specified in the game design in an UML like specification could be in)Tj ET BT 70.875 587 TD 0.162 Tw (one hand coded and tested using software engineering techniques and on the other hand used on a level scripting)Tj ET BT 70.875 572.75 TD 0 Tw (tool like Virtools. Working on this field is the next step of our research.)Tj ET BT /F1 12 Tf 70.875 542 TD (References)Tj ET BT /F2 10 Tf 70.875 510.5 TD 0.67 Tw ([1] V. Gal, C. Le Prado, S. Natkin, L. Vega, Processus et outils utilis\216s pour la conception et la r\216alisation des)Tj ET BT 70.875 496.25 TD 0 Tw (jeux vid\216o, Rapport CEDRIC, A para\224tre, juin 2002.)Tj ET BT 70.875 482 TD ([2] A. Rollins, D. Morris, "Game Architecture and Design", Coriolis Ed, 2000)Tj ET BT 70.875 468 TD ([3] Bob Bates, Game Design, The art and business of creating games. Ed Prima Publishing, 2001.)Tj ET BT 70.875 453.75 TD ([4] Grigoire Burdea, Philippe Coiffet, La R\216alit\216 Virtuelle, Herm\217s 1993.)Tj ET BT 70.875 439.5 TD ([5]Ariane Mallender, Ecriture pour le multim\216dia, Dunod 1999.)Tj ET BT 70.875 425.5 TD ([6] J. Weske, "Digital Sound and Music in computer games",)Tj ET BT 0 0 1 rg 0 0 1 RG 70.875 411.25 TD (http://tu-chemnitz.de/phil/hypertext/gamesound/)Tj ET 70.75 410 193.5 0.5 re f BT 0 g 0 G 70.875 397 TD (Web game developers site: )Tj 0 0 1 rg 0 0 1 RG 110.513 0 TD (www.gamasutra.com)Tj ET 181.25 395.75 85 0.5 re f BT /F3 10 Tf 0 g 0 G 70.875 385.25 TD ([7] D. Johnson, . Wiles, \322Computer games with intelligence\323, 2002)Tj ET BT 0 0 1 rg 0 0 1 RG 70.875 373.75 TD (http://www.infenv.csee.uq.edu.au/games.pdf)Tj ET 70.75 372.25 178.75 0.5 re f BT 0 g 0 G 70.875 362.25 TD ([8] S. Woodcock, \322Game AI : The state of the industry\323, 1999)Tj ET BT 0 0 1 rg 0 0 1 RG 70.875 350.75 TD (http://www.gamasutra.com/features/19990820/game_ai_01.htm)Tj ET 70.75 349.25 255.75 0.5 re f BT 0 g 0 G 70.875 339.25 TD ([9] S. Woodcock, \322Game AI : The state of the industry\323, 2000)Tj ET BT 0 0 1 rg 0 0 1 RG 70.875 327.75 TD (http://www.gamasutra.com/features/20001101/woodcock_pvf.htm)Tj ET 70.75 326.25 266.25 0.5 re f BT 0 g 0 G 70.875 316.25 TD ([10] Get artificial life !)Tj ET BT 0 0 1 rg 0 0 1 RG 70.875 304.75 TD (http://ai.about.com/library/weekly/aa032700a.htm)Tj ET 70.75 303.25 200.75 0.5 re f BT 0 g 0 G 70.875 293.25 TD ([11] J.P. Ponsard, Logique de la n\216gociation et th\216orie des jeux, Ed. de l\325organisation, 1997)Tj ET BT 70.875 281.75 TD ([12] B. Guerrier, La th\216orie des jeux, Economica, 2002)Tj ET BT /F1 10 Tf 70.875 253.75 TD (Games)Tj ET BT /F2 10 Tf 70.875 239.5 TD (Rayman, Ubisoft, 1995 $PS1$)Tj ET BT 70.875 225.5 TD (Silent Hill 2, Komany 2001 $PS2$)Tj ET BT 70.875 211.25 TD (Gran Turismo 3, Sony, Polyphony Digitals, 2001 $PS2$)Tj ET BT 70.875 197.25 TD (Jack and Dexter, Sony, Naughty Dog, 2001 $PS2$)Tj ET BT 70.875 183 TD (Metal Gear Solid 2, Komany, 2002 $PS2$)Tj ET BT 70.875 168.75 TD (Black and White, Electronic Arts, Lionhead Studio, 2001 $PC$)Tj ET BT 70.875 154.75 TD (Alien vs Predators, Fox Interactive, Sierra, 2002 $PC$)Tj ET BT 70.875 140.5 TD (Sim city, Maxis, 1989 $PC$)Tj ET BT /F3 10 Tf 70.875 128.75 TD (The Sims and add ons, Electronic Arts, 2000, 2001, 2002 $PC$)Tj ET BT 70.875 117.25 TD (Doom, ID Software, 1993 $PC$)Tj ET BT 70.875 105.75 TD (Civilization, Coregames, 1989 $PC$)Tj ET BT 70.875 87.5 TD ( )Tj ET 70.75 89.5 144 0.5 re f BT /F3 6.5 Tf 70.875 78.25 TD (3)Tj /F3 10 Tf 3.25 -4.5 TD ( http://)Tj /F2 10 Tf 0 0 1 rg 0 0 1 RG 26.392 0 TD (www.irisa.fr/siames)Tj ET 100.5 72.5 80.5 0.5 re f endstream endobj 46 0 obj 4895 endobj 44 0 obj << /Type /Page /Parent 31 0 R /Resources <> /ProcSet 2 0 R >> /Contents 45 0 R >> endobj 48 0 obj << /Length 49 0 R >> stream 0.25 w BT /F3 10 Tf 70.875 762.25 TD 0 Tc 0 Tw (Quake, ID Software, 1995 $PC$)Tj ET BT 70.875 750.75 TD (Fields of Battle, 1995 $PC$)Tj ET BT 70.875 739.25 TD (Return to Castle Wolfenstein, Activision, 2001 $PC$)Tj ET BT 70.875 727.75 TD (Conflict Zone, Ubi Soft, 2001 $PC$)Tj ET endstream endobj 49 0 obj 289 endobj 47 0 obj << /Type /Page /Parent 31 0 R /Resources <> /ProcSet 2 0 R >> /Contents 48 0 R >> endobj 6 0 obj << /Type /Font /Subtype /TrueType /Name /F1 /BaseFont /Times-Bold /Encoding /MacRomanEncoding >> endobj 7 0 obj << /Type /Font /Subtype /TrueType /Name /F2 /BaseFont /Times-Roman /Encoding /MacRomanEncoding >> endobj 8 0 obj << /Type /FontDescriptor /FontName /CIBCHK#2BTimesNewRomanPSMT /Flags 32802 /FontBBox [ -250 -225 1000 900 ] /MissingWidth 250 /StemV 93 /StemH 31 /ItalicAngle 0 /CapHeight 656 /XHeight 437 /Ascent 900 /Descent -225 /Leading 50 /MaxWidth 1000 /AvgWidth 536 /Style << /Panose <050102020600000000000000> >> /FontFile2 50 0 R >> endobj 50 0 obj << /Filter /FlateDecode /Length 51 0 R /Length1 53 0 R /Length2 52 0 R /Length3 54 0 R >> stream H‰lV TW½ïÿªn—¨((FiADÜ“¸ ˆ÷Ý,Ú";H+¨àŠ7ÜI"¢hPq‰»˜‰¢ÆEÔGq‹t3hW˜3'9“ºçW×¯úýê¾wïûÝ ‰ÃG{t¾U/ù2ß¹Ãcœ„É