Game semantics (German: dialogische Logik) is an approach to the semantics of logic that grounds the concepts of truth or validity on game-theoretic concepts, such as the existence of a winning strategy for a player. Paul Lorenzen was the first to introduce a game semantics for logic, doing so in the late 1950s. Since then, a number of different game semantics have been studied in logic. Game semantics has also been applied to the formal semantics of programming languages.

Intuitionistic logic, denotational semantics, linear logic

The primary motivation for Lorenzen and Kuno Lorenz was to find a game-theoretic (their term was "dialogical" Dialogische Logik) semantics for intuitionistic logic. Blass was the first to point out connections between game semantics and linear logic. This line was further developed by Samson Abramsky, Radhakrishnan Jagadeesan, Pasquale Malacaria and independently Martin Hyland and Luke Ong, who placed special emphasis on compositionality, i.e. the definition of strategies inductively on the syntax. Using game semantics, the authors mentioned above have solved the long-standing problem of defining a fully abstract model for the programming languge PCF. Consequently, game semantics has led to fully abstract semantic models for a variety of programming languages and, to new semantic-directed methods of software verification by software model checking.

Quantifiers

Foundational considerations of game semantics have been more emphasised by Jaakko Hintikka and Gabriel Sandu, especially for Independence-friendly logic (IF logic, more recently Information-friendly logic), a logic with "branching" (or partially ordered) quantifiers. It was thought that the principle of compositionality fails for these logics, so that a Tarskian truth definition could not provide a suitable semantics. To get around this problem, the quantifiers were given a game-theoretic meaning. Specifically, a universal quantifier and existential quantifier represent a choice by a player from the domain. In the universal case, a natural name for the player is "Falsifier"; in the existential, "Verifier". Note that a single counterexample falsifies a universally quantified statement, and a single example suffices to verify an existentially quantified one. Wilfred Hodges has proposed a compositional semantics and proved it equivalent to game semantics for IF-logics. Foundational considerations have motivated the works of others, such as Japaridze's computability logic.

Articles

• Krabbe, E. C. W., 2001. "Dialogue Foundations: Dialogue Logic Revisited," Supplement to the Proceedings of The Aristotelian Society 75: 33-49.

Books

• K. Lorenz, P. Lorenzen: Dialogische Logik, Darmstadt 1978
• P. Lorenzen: Lehrbuch der konstruktiven Wissenschaftstheorie, Stuttgart 2000 ISBN 3-476-01784-2
• R. Inhetveen: Logik. Eine dialog-orientierte Einführung., Leipzig 2003 ISBN 3-937219-02-1

Links

• GALOP: Workshop on Games for Logic and Programming Languages
• Game Semantics or Linear Logic?
• Computability Logic Homepage
• Stanford Encyclopedia of Philosophy entry on Logic and Games

This guide is licensed under the GNU Free Documentation License. It uses material from the Wikipedia.

A game mechanic is a rule or set of rules intended to produce an enjoyable set of outcomes in a game. Complex games, such as role-playing games, are built using a large number of interlocking game mechanisms. The entirety of the game experience or set of game mechanics is called game play.

The interaction of the various Game_mechanic.html in a game determines the complexity and level of player interaction in the game. Designing a system of mechanics that interact well to produce a satisfying game is a challenging task, even for professional game designers. Some forms of game mechanic have been used in games for centuries, while others are relatively new, some having been invented within the past decade. The creation of new Game_mechanic.html, and ways in which existing ones can interact, is the ongoing goal of game designers.

Game_mechanic.html fall into several more or less well-defined categories.

Game play mechanics

These are mechanics that control how the players play the game.

Action points

These control what players may do on their turns in the game by allocating each player a budget of action points each turn. These points may be spent performing various actions according to the game rules, such as moving pieces, drawing cards, collecting money, etc. This type of mechanic is common in many German-style board games.

Auction or bidding

Some games use an auction or bidding system in which the players make competitive bids to determine which player gets the right to perform particular actions. Such an auction can be based on different forms of "payment":

• The winning bidder must pay for the won privilege with some form of game resource (game money, points, etc) (e.g.: RA).
• The winning bidder does not pay upon winning the auction, but the auction is a form of promise that the winner will achieve some outcome in the near future. If this outcome is not achieved, the bidder pays some form of penalty. Such a system is used in many trick-taking games, such as contract bridge.

In some games the auction determines a unique player who gains the privilege; in others the auction orders all players into a sequence, often the sequence in which they take turns during the current round of game play.

Cards

These involve the use of cards similar to playing cards to act as a randomiser and/or to act as tokens to keep track of states in the game.

A common use is for a deck of cards to be shuffled and placed face down on or near the game playing area. When a random result is called for, a player draws a card and what is printed on the card determines the outcome of the result.

Another use of cards occurs when players draw cards and retain them for later use in the game, without revealing them to other players. When used in this fashion, cards form a game resource.

Capture

In some games, the number of tokens a player has on the playing surface is related to his current strength in the game. In such games, it can be an important goal to capture opponent's tokens, meaning to remove them from the playing surface.

Captures can be achieved in a number of ways:

• Moving one of one's own tokens into a space occupied by an opposing token (e.g. chess).
• Jumping a token over the space occupied by an opposing token (e.g. draughts).
• Declaring an "attack" on an opposing token, and then determining the outcome of the attack, either in a deterministic way by the game rules, or by using a randomising method.
• Surrounding a token with one's own tokens in some manner (e.g. go).
• Playing cards or other resources that the game allows to be used to capture tokens.

In some games, captured tokens are simply removed and play no further part in the game (e.g. chess). In others, captured tokens are removed but can return to play later in the game under various rules (e.g. backgammon). Less common is the case in which the capturing player takes possession of the captured tokens and can use them himself later in the game (e.g. shogi).

Dice

These involve the use of dice, usually as randomisers. Most dice used in games are the standard cubical dice numbered from 1 to 6, but increasing numbers of games make use of polyhedral dice or dice marked with symbols other than numbers.

The most common use of dice is to randomly determine the outcome of an interection in a game. An example is a player rolling dice to determine how many board spaces to move a game token.

Dice also often determine the outcomes of in-game conflict between players, with different outcomes of the dice roll of different benefit (or adverse effect) to each player involved. This is useful in games that simulate direct conflicts of interest.

Movement

Many board games involve the movement of playing tokens. How these tokens are allowed to move, and when, is governed by movement mechanics.

Some game boards are divided into more or less equally-sized areas, each of which can be occupied by one or more game tokens. (Often such areas are called squares, even if not strictly square in shape.) Movement rules will specify how and when a token can be moved to another area. For example, a player may be allowed to move a token to an adjacent area, but not one further away. Dice are sometimes used to randomise the allowable movements.

Other games, particularly miniatures games are played on surfaces with no marked areas. A common movement mechanic in this case is to measure the distance which the miniatures are allowed to move with a ruler.

Resource management

Many games involve the management of resources. Examples of game resources include game tokens, game money, and game points. Resource management involves the players establishing relative values for various types of available resources, in the context of the current state of the game and the desired outcome (i.e. winning the game). The game will have rules that determine how players can increase, spend, or exchange their various resources. The skilful management of resources under such rules allows players to influence the outcome of the game.

Role-playing

Role-playing games often rely on mechanics that determine the effectiveness of in-game actions by how well the player acts out the role of a fictional character. While early role-playing games such as the first edition of Dungeons & Dragons relied heavily on randomisers such as dice to determine the outcomes of role-playing actions such as diplomatic negotiations, later generations of games often use the standard of "good role-playing" as a modifier or even the sole determinant of whether such an action is successful.

Tile-laying

Many games use tiles - flat, rigid pieces of a regular shape - that can be laid down on a flat surface to form a tessellation. Usually such tiles have patterns or symbols on their surfaces, that combine when tessellated to form game-mechanically significant combinations.

The tiles themselves are often drawn at random by the players, either immediately before placing them on the playing surface, or in groups to form a pool or hand of tiles from which the player may select one to play.

Tiles can be used in two distinct ways:

• The playing of a tile itself is directly significant to the outcome of the game, in that where and when it is played contributes points or resources to the player.
• Tiles are used to build a board upon which other game tokens are placed, and the interaction of those tokens with the tiles provides game points or resources.

Examples of tile mechanics include: Scrabble, in which tiles are letters and players lay them down to form words and score points; and Tikal, in which players lay tiles representing newly explored areas of jungle, through which archaeologists (represented by tokens) must move to score game points.

Victory condition mechanics

These mechanics control how a player wins the game.

Goals

This is the most general sort of victory condition, which can be broad enough to encompass any method of winning, but here refers to game-specific goals that are usually not duplicated in other games. An example is the checkmate of a king in chess.

Piece elimination

Some games with capture mechanics are won by the player who removes all, or a given number of, the opponents' playing pieces.

Puzzle guessing

Some games end when a player guesses (or solves by logic) the answer to a puzzle or riddle posed by the game. The player who guesses successfully wins. Examples include hangman and zendo.

Races

Many simple games (and some complex ones) are effectively races. The first player to advance one or more tokens to or beyond a certain point on the board wins. Examples: backgammon, ludo.

Structure building

The goal of a structure building game is to acquire and assemble a set of game resources into either a defined winning structure, or into a structure that is somehow better than those of other players. In some games, the acquisition is of primary importance (e.g. concentration), while in others the resources are readily available and the interactions between them form more or less useful structures (e.g. poker).

Territory control

A winner may be decided by which player controls the most "territory" on the playing surface, or a specific piece of territory. This is common in wargames, but is also used in more abstract games such as go.

Victory points

These are points that a player accumulates over the course of a game. The winner can be decided either by:

• The first player to reach a set number of points.
• The player with the most points at a predetermined finishing time or state of the game.

This mechanic is often used explicitly in German-style board games, but many other games are played for points that form a winning condition. Victory points may be partially disguised in the role of game resources, with play money being a common example.

Gameplay vs. Game_mechanic.html in video games

Generally, the term "gameplay" in video game terminology is used to describe the overall experience of playing the game excluding the factors of graphics, sound, and the storyline. This is the very essence of a game. The term "Game mechanics" refers to sub elements of the gameplay, but particularly the primary control and movement features of the game (thus excluding things like level design or AI).

This guide is licensed under the GNU Free Documentation License. It uses material from the Wikipedia.

Artistic computer game modification involves the use of a computer game for the creation of a digital artwork. Also referred to as art modding, and game modding. Art mods are not quite the same as art games, although they do share some similarities.

Various genres and styles of art modding exist. Genres or categories are rarely clear cut in this multi-media format, however than can be roughly described based on:

1. Techniques
2. Outcomes

Techniques

Narrative Machinima

Screen-based narratives made using pre-existing, often modded, computer games. Many of these explore innovative conceptual territory.

Examples:

• Red vs Blue

Sequential Machinima

With the use of certain Photoshop filters, comics fonts, and fonts for speech bubbles, in-game screenshots can also be used to quickly create graphic novels.

Abstract Machinima

Screen-based visual abstractions made using pre-existing, often modded, computer games.

Sonichima

Sound works produced within a game-based production environment.

Examples:

• Tree Wave

Generative Art Mods

Exploit the real time capabilities of game technologies to produce ever-renewing art works.

Performative Interventions

Disrupt in-game norms to expose underlying functions of game play.

Site-specific Installations and site-relative mods

Compare similarities and differences between real and virtual worlds, drawing us further into a realit of fantasy.

Real time performance instruments

Allow audio and visual artists to create stunning, live performances in a range of virtual entertainment environments.

Like games, artistic game mods may be single player or multiplayer. Multiplayer works make use of networked environments to develop new models of interactivity and collaborative production.

Artists

• Brody Condon http://www.tmpspace.com
• Eddo Stern http://www.c-level.cc
• Critical Art Ensemble
• Cory Arcangel
• Paul Slocum
• Jean Paul Birchard
• Jeffrey F. Donaldson http://audiovideo.sevcom.com
• Fuchs-Eckerman http://www.t0.or.at/~fuchs-eckermann/
• Glaznost
• Jodi http://sod.jodi.org/ and http://www.untitled-game.org/
• Julian Oliver http://www.selectparks.net
• Linda Erceg
• Nybble-Engine http://www.climax.at/nybble-engine/
• Palle Torsson http://palletorsson.com
• Rebecca Cannon http://www.selectparks.net
• Retroyou http://www.retroyou.org
• Stephen Honegger
• Tobias Bernstrup http://www.bernstrup.com

Timeline

• 'Mimesia' by Richard Brown.

2004

• Prepared Playstation by RSG.
• Voldo Dance by Chris Brandt.

Theorists

• Rebecca Cannon
• Anne-Marie Schleiner
• Mary Flanagan
• Celia Pearce
• Julian Oliver
• Pippa Stalker
• Christopher Dodds

Links

• Selectparks is an online database of art modding, art games, tutorials, news, downloads, forums, etc.
• Cracking the Maze - Game Plug-ins and Patches as Hacker Art is an online exhibition about artistic game patches, curated by SJSU's CADRE Laboratory for New Media

References

• Introduction to artistic computer game modification (PDF file)
• Switch, Art & Games issue, 1999, online magazine of the CADRE Laboratory for New Media, San Jose State University

This guide is licensed under the GNU Free Documentation License. It uses material from the Wikipedia.

Video: 10 Years of Computer Game Design

A game artist is responsible for all of the aspects of game development that calls for visual art. Game artists are often noted in role-playing games, collectible card games, and computer and video games.

Computer and video games

Adrian Carmack, working on Doom, creating a clay model for the Baron of Hell.

In modern computer and video games, game artists create 2D art used as textures or 3D models and animations.

They often design the look of the character through concept art and render them to be integrated into the game. They are also responsible for designing scenery, props, and any other visual effects in the game, like FMVs.

The abilities of early computers were so limited that having specialized personnel for art was unnecessary. Up until about the early 1990s, almost all art for video games were created by the game programmers. Most early video game art was simply created in code by specifying pixel colors and coordinates.

In recent times, dedicated video game artists make up a large part of many game development teams.

This guide is licensed under the GNU Free Documentation License. It uses material from the Wikipedia.

A toy is something to play with, for children, adults or both. They may either be the sole device used in an enjoyable activity or one of many. Toys have existed for thousands of years; dolls either of infants, animals, or soldiers, and miniature representations of the tools of adults are readily found at archaeological sites. The Inca, for example, had a rolling toy even though their adult culture did not employ the wheel. Two comparatively recent developments of toys have been their mass production and copyrighting. A number of these copyrighted, mass-produced toys are associated with particular decades in the twentieth century.

Many successful films, television programs, books and sport teams have official merchandise, quite often toys will be made and sold. Some notable examples are Star Wars and Manchester United. The haulage company owned by Eddie Stobart produced model lorries, which now subsidise the business.

Toys sold primarily as entertainment for adults are termed executive toys as some were originally marketed as a way to reduce executive stress. The term also avoids 'adult toy' which has connotations of sex toys used to enhance sexual excitement.

Some things usually thought to be games are actually toys, such as the computer game SimCity and its spinoffs, which are called software toys. As a rule, if something game-like lacks an explicit end state, it is a toy, not a game.

Toys by culture

This is not a complete list.

US pioneers: In the 1800's many families crossing the great plains were known as pioneers. The pioneer children often had such toys as tops and dolls. They also played simple games like 'hide and seek'.

America: Today Americans have all sorts of toys, the main ones being listed below. But this is and era of computers and video games, and many children (and even adults) have toys such as the Xbox, Gamecube, etc. and computer games such as Half-life.

Examples

• Construction toys

Erector Set
Gami, Plastic Origami
Jovo
K'NEX
LEGO
Lincoln Logs
Märklin
Meccano
Mega Bloks
Stickle bricks
Tinkertoy
Zome

• Figures

Dolls
Raggedy Ann
Action figures
Playmobil
Digital pet
Jumping Jack
Toy soldier
Stuffed animals
Pound Puppies
Teddy bear
Sock monkey

• Drawing toys

Decoder pen
Spirograph
Stencil

• Educational toy

Ant Farm

• Mechanical toys

Jack-in-the-Box
Magic trick
Newton's cradle
Easy Bake Oven

• Mechanical puzzle

Rubik's Cube

• Miniaturized items

Toy piano
Toy weapon

• Model building

Model car
Model railway
Carpet railway

• Model collecting

Matchbox cars

• Science and optical

Kaleidoscope
View-master
Spinning top
Zoetrope

• physical activity and dexterity toys

Bungee Balls
Frisbee (1950s)
Hula Hoop (1950s)
Marbles
Pogo stick
Soap-box cart
Footbag
Chinese yo-yo (diabolo)
Yo-Yo (1930s onwards)

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia.