The document discusses game artificial intelligence and techniques used to generate intelligent behavior in non-player characters in computer and video games. It covers topics like machine learning, reinforcement learning, pathfinding algorithms, and different data structures used to represent game boards and chess positions. Game AI aims to create behavior that feels natural to the player while obeying the rules of the game. Various computer science disciplines are required to develop effective game AI, and different types of games require different AI techniques.

1. By:
Jojo naqvi

2.  Game artificial intelligence refers to techniques
used in computer and video games to produce
the illusion of intelligence in the behavior of
non-player characters (NPCs)
 Hacks and cheats are acceptable and, in many
cases, the computer abilities must be toned
down to give human players a sense of fairness.
E.g racing and shooting
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3.  AI has continued to improve, with aims set on a
player being unable to tell the difference
between computer and human players.
 A game must „feel‟ natural
◦ Obey laws of the game
◦ Characters aware of the environment
◦ Path finding (A* algorithm)
◦ Decision making
◦ Planning
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4.  Games are fun!
 They are limited, well-defined rules
 They are one of the few domains that allow us to
build agents.
 Studying games teaches us how to deal with other
agents trying to foil our plans
 Nice, clean environment with clear criteria for
success
 Game playing is considered an intelligent human
activity.
 AI has always been interested in abstract games.
 Games present an ideal environment where hostile
agents may compete.
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5.  Machine Learning - also
known as ML, is a field of
artificial intelligence
which focuses on
developing algorithms
that can learn to predict,
classify, control, or solve
problems.
 Reinforcement Learning -
Taking past data that the
AI has recorded and
using it to influence
behavior and choices
made in the future.
 Waypoint Graph - is a
collection of waypoints
linked up to form the
information about what
areas of a level can be
traversed by an actor
during path finding.
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6.  Game AI is about the illusion of human behaviour
◦ Smart, to a certain extent (Creativity)
◦ Non-repeating behaviour
◦ Emotional influences (Irrationality, „Personality‟)
◦ Body language to communicate emotions
◦ Being integrated in the environment
 Game AI needs various computer science disciplines
◦ Knowledge Based Systems
◦ Machine Learning
◦ Multi-agent Systems
◦ Computer Graphics & Animation
◦ Data Structures
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7.  Strategy Games
◦ Real-Time Strategy (RTS)
◦ Turn-Based Strategy (TBS)
◦ Helicopter view
 Role-Playing Games (RPG)
◦ Single-Player
◦ Multi-Player (MMORPG)
 Action Games
◦ First-Person Shooters (FPS)
◦ First-Person Sneakers
 Sports Games
 Simulations
 Adventure Games
 Puzzle Games
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9. 23-Mar-20009Artificial Intelligence - CMT310 9

10.  providing more multi-human gaming
opportunities
◦ Teaming up with/against other
humans
◦ Large environments
◦ Changing environments
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11.  A* algorithm gives the shortest path from
predator to prey in a tiled environment.
 This can be used for chase/evade.
 However, alternatives exist.

12. if (predatorX > preyX) {
predatorX--;
} else if (predatorX == preyX) {
// do nothing
} else {
predatorX++;
}
if (predatorY > preyY) {
predatorY--;
} else if (predatorY == preyY) {
// do nothing
} else {
predatorY++;
}
assuming tiled environment
Predator is at coordinates (predatorX,predatorY).
Prey is at coordinates (preyX,preyY).
This algorithm will update predator coordinates.
Algorithm for prey (evade) is just the opposite.

13.  This chase algorithm is not natural.
 Suppose the prey and predator are at the
coordinates below, then the algorithm will
give the following path.
prey
predator

14.  Instead we want a more natural path like
below.
prey
predator

15. What is Data Structure?
 In computer science, a data structure is a particular
way of storing and organizing data in a computer
so that it can be used efficiently.
 Data structures are used in almost every program
or software system.
 Data structures provide a means to manage huge
amounts of data efficiently.

16. What is Chess?
 Chess is a two-player board game played on a
chessboard, a square checkered board with
64 squares arranged in an eight-by-eight grid. It
is one of the world's most popular games, played
by millions of people worldwide.
 In computer chess, software developers must
choose a data structure to represent chess
positions on the chessboard

18.  In computer chess, software developers must
choose a data structure to represent the chess
board and chess positions. Several data structures
exist, collectively known as board representations.
Some are given below
 Offset board representation
 Bitmap board representation
 Two-dimensional array representation
 0X88 board representation
 Huffman encoding technique for chess pieces

19.  horizontal lines are called “Ranks”
 vertical lines are called “Columns” (column A,
column B… column H)
 Talking about indexes of array you can
imagine an 8 x 8 chess board in this way:
 The formula to calculate a square is:
 Index = rank * 8 + column
 where rank 1, rank 2,…, rank 8 and column
A, column B,…, column H are 0,1,2…7; the
index of square “e4″ is : 3 * 8 + 4=28 .

21.  Where c is a bit representing the color of the piece (1 = LIGHT, 0 = DARK)