Programming Game Behaviour (Game AI)

1
Programming Game Behaviour(Game AI)

• Introduction
• Bryan Duggan

2
Learning Outcomes

• Compare approaches to implementing perception and
  propose optimised solutions to perception
  problems.
• Critically analyse how perception is implemented
  in commercial computer games.
• Implement a variety of path following and path
  finding algorithms.
• Demonstrate an understanding of the issues
  involved in practical, optimised path finding.
• Use UML and object orientated design to model
  both technical architectures and behaviours in
  computer games.
• Propose architectures for NPC higher order
  decision making.
• Critically analyse how the techniques learned on
  the course are used in commercial games.

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Game AI is all about

• Finite State Machines
• Path Finding
• Steering
• Scripting
• Fuzzy logic
• Agents
• Probability (Stochastic/Bayesian methods)
• Tricks (good acting, following eyes etc)

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Its not about

• Neural networks
• Machine learning
• CBR
• Expert systems
• Natural language processing
• Markov Chains
• Basically AI!!

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Example from Half Life 2

• There are 2 conceits that the players and the
  designers are complicit in
• If

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How to make good game AI

• Make the eyes of the NPCs follow the player
• Make the NPCs harder to kill

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Course Overview

• Advanced steering
• Neutons laws of force and acceleration
• Graphs
• Navigation graphs, dependency graphs and state
  graphs
• Implementing a flexible graph class using C
  templates
• Automatic generation of navigation graphs
• Graph search algorithms
• Dijstras shortest path algorithm
• The A algorithm

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Course Overview

• Perception
• FOV
• Sound
• Collisions
• Distance from player
• Intersection of 2 lines
• Intersection of ray and plane
• Game AI using state machines
• The state machine design pattern
• State transition diagrams
• Agents?
• Modding?

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Assessment

• Team 1 Skinned Meshes (skeletal animation)
• A class that can be integrated into DalekWorld
• Encapsulates all the code required to animate a
  mesh into a simple API
• Use books/internet resources as you like
• A lecture (max 1 hour)
• A lab
• A solution

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Assessment

• 3 Team projects
• Team 2 3D Positional Audio
• A class or framework of classes that can be
  integrated into DalekWorld
• Encapsulates all the code required to animate a
  mesh into a simple API
• Bind the audio to the animation
• Use books/internet resources as you like
• A lecture (max 1 hour)
• A lab
• A solution

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Assessment

• Team 2 World Loader
• A new loader for DalekWorld based on x Files
• Hierarchical
• Use books/internet resources as you like
• A lecture (max 1 hour)
• A lab
• A solution

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Books

• Semester 1
• Introduction to 3D Game Programming with DirectX
  9.0
• Frank D. Luna
• Semester 2
• Programming Game AI by Example
• Mat Buckland

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Tools

• Microsoft Visual C (Anything from version 6.0
  or above with the latest service packs will do
  fine)
• Latest DirectX 9 SDK

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Web Resources

• Course Notes
• http//webcourses.dit.ie
• Games Developers
• http//www.gameasutra.com/
• http//www.gamedevelopers.ie
• General Gaming
• http//www.pczone.co.uk
• http//www.gamespot.com