Algorithms and Networking for Computer Games

402 Pages·2017·12.127 MB·English

by  Jouni Smed, Harri Hakonen

AlgorithmsandNetworkingfor
ComputerGames
Algorithms and Networking for
Computer Games
SecondEdition
JouniSmed
UniversityofTurku
Turku,FI
HarriHakonen
Turku,FI
Thiseditionfirstpublished2017
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LibraryofCongressCataloging-in-PublicationData
Names:Smed,Jouni,author.|Hakonen,Harri,author.
Title:Algorithmsandnetworkingforcomputergames/JouniSmed,HarriHakonen.
Description:Secondedition.|Hoboken,NJ,USA:JohnWiley&SonsInc.,2017.|
Includesbibliographicalreferencesandindex.
Identifiers:LCCN2017005948(print)|LCCN2017006972(ebook)|ISBN9781119259763(cloth)|
ISBN9781119259824(AdobePDF)|ISBN9781119259831(ePub)
Subjects:LCSH:Computergames–Programming.|Computeralgorithms.
Classification:LCCQA76.76.C672S622017(print)|LCCQA76.76.C672(ebook)|
DDC794.8/1526–dc23
LCrecordavailableathttps://lccn.loc.gov/2017005948
CoverDesign:Wiley
CoverImage:©Pobytov/GettyImages
Setin10/12ptWarnockProbyAptaraInc.,NewDelhi,India
10 9 8 7 6 5 4 3 2 1
v
Contents
ListofFigures xi
ListofTables xv
ListofAlgorithms xvii
Preface xix
 Introduction 1
1.1 AnatomyofComputerGames 4
1.2 GameDevelopment 5
1.2.1 Phasesofdevelopment 7
1.2.2 Documentation 8
1.2.3 Otherconsiderations 9
1.3 SyntheticPlayers 10
1.3.1 Humanness 11
1.3.2 Stance 12
1.4 Multiplaying 12
1.5 InteractiveStorytelling 13
1.5.1 Approaches 14
1.5.2 Storytellingingames 15
1.6 OutlineoftheBook 17
1.6.1 Algorithms 17
1.6.2 Networking 18
1.7 Summary 18
Exercises 19
PartI Algorithms 23
 RandomNumbers 25
2.1 LinearCongruentialMethod 26
2.1.1 Choiceofparameters 29
2.1.2 Testingtherandomness 30
2.1.3 Usingthegenerators 31
2.2 DiscreteFiniteDistributions 33
2.3 RandomShuffling 38
2.4 Summary 41
Exercises 41
vi Contents
 Noise 47
3.1 ApplyingNoise 47
3.2 OriginofNoise 49
3.3 Visualization 51
3.4 Interpolation 52
3.4.1 Utilityroutinesforvalueconversions 53
3.4.2 Interpolationinasingleparameter 56
3.4.3 Interpolationintwoparameters 58
3.5 CompositionofNoise 60
3.6 PeriodicNoise 62
3.7 PerlinNoise 63
3.8 WorleyNoise 68
3.9 Summary 76
Exercises 76
 ProceduralGeneration 81
4.1 TerrainGeneration 82
4.2 MazeAlgorithms 88
4.2.1 Depth-firstalgorithm 91
4.2.2 RandomizedKruskal’salgorithm 91
4.2.3 RandomizedPrim’salgorithm 93
4.3 L-Systems 93
4.3.1 Examples 95
4.3.2 Citygeneration 96
4.4 HierarchicalUniverseGeneration 99
4.5 Summary 101
Exercises 102
 Tournaments 105
5.1 RankAdjustmentTournaments 107
5.2 EliminationTournaments 112
5.3 ScoringTournaments 119
5.4 Summary 122
Exercises 125
 GameTrees 129
6.1 Minimax 130
6.1.1 Analysis 132
6.1.2 Partialminimax 134
6.2 Alpha-BetaPruning 137
6.2.1 Analysis 139
6.2.2 Principalvariationsearch 140
6.3 MonteCarloTreeSearch 142
6.4 GamesofChance 149
6.5 Summary 153
Exercises 153
Contents vii
 PathFinding 159
7.1 DiscretizationoftheGameWorld 160
7.1.1 Grid 160
7.1.2 Navigationmesh 162
7.2 FindingtheMinimumPath 164
7.2.1 Evaluationfunction 165
7.2.2 Properties 165
7.2.3 AlgorithmA* 167
7.3 RealizingtheMovement 169
7.4 Summary 171
Exercises 171
 GroupMovement 175
8.1 Flocking 175
8.2 Formations 180
8.2.1 Coordinatingformations 181
8.2.2 Behaviour-basedsteering 183
8.2.3 Fuzzylogiccontrol 184
8.2.4 Mass–springsystems 186
8.3 Summary 187
Exercises 187
 Decision-Making 189
9.1 Background 189
9.1.1 Levelsofdecision-making 190
9.1.2 Modelledknowledge 191
9.1.3 Methods 192
9.2 FiniteStateMachines 196
9.2.1 ComputationalFSM 198
9.2.2 MealyandMooremachines 202
9.2.3 Implementation 203
9.2.4 Discussion 205
9.3 InfluenceMaps 208
9.4 AutomatedPlanning 210
9.5 Summary 214
Exercises 215
 ModellingUncertainty 221
10.1 StatisticalReasoning 221
10.1.1 Bayes’theorem 221
10.1.2 Bayesiannetworks 223
10.1.3 Dempster–Shafertheory 224
10.2 FuzzySets 227
10.2.1 Membershipfunction 228
10.2.2 Fuzzyoperations 229
10.2.3 Defuzzification 231
10.3 FuzzyConstraintSatisfactionProblem 231
viii Contents
10.3.1 Modellingthecriteriaasfuzzysets 233
10.3.2 Weightingtheimportanceofcriteria 235
10.3.3 Aggregatingthecriteria 235
10.3.4 Makingadecision 236
10.4 Summary 238
Exercises 238
PartII Networking 241
 CommunicationLayers 243
11.1 PhysicalPlatform 244
11.1.1 Resourcelimitations 245
11.1.2 Transmissiontechniquesandprotocols 246
11.2 LogicalPlatform 247
11.2.1 Communicationarchitecture 247
11.2.2 Dataandcontrolarchitecture 249
11.3 NetworkedApplication 250
11.4 Summary 251
Exercises 252
 CompensatingResourceLimitations 255
12.1 AspectsofCompensation 256
12.1.1 Consistencyandresponsiveness 256
12.1.2 Scalability 258
12.2 ProtocolOptimization 262
12.2.1 Messagecompression 262
12.2.2 Messageaggregation 263
12.3 DeadReckoning 263
12.3.1 Prediction 264
12.3.2 Convergence 266
12.4 LocalPerceptionFilters 268
12.4.1 Lineartemporalcontour 271
12.4.2 Addingbullettimetothedelays 275
12.5 SynchronizedSimulation 277
12.6 InterestManagement 279
12.6.1 Aura-basedinterestmanagement 279
12.6.2 Zone-basedinterestmanagement 280
12.6.3 Visibility-basedinterestmanagement 280
12.6.4 Class-basedinterestmanagement 281
12.7 CompensationbyGameDesign 282
12.7.1 Shortactiveturns 283
12.7.2 Semi-autonomousavatars 284
12.7.3 Interactionviaproxies 284
12.8 Summary 285
Exercises 286
Contents ix
 CheatingPrevention 289
13.1 TechnicalExploitations 290
13.1.1 Packettampering 291
13.1.2 Look-aheadcheating 292
13.1.3 Crackingandotherattacks 297
13.2 Collusion 298
13.2.1 Classification 299
13.2.2 Collusiondetection 301
13.3 RuleViolations 303
13.4 Summary 304
Exercises 304
 OnlineMetrics 307
14.1 Players 310
14.2 Monetization 311
14.3 Acquisition 312
14.4 GameSession 313
14.5 Summary 313
Exercises 314
Appendices 315
A PseudocodeConventions 317
A.1 ChangingtheFlowofControl 320
A.1.1 Expressions 320
A.1.2 Controlstructures 322
A.2 DataStructures 325
A.2.1 Valuesandentities 325
A.2.2 Datacollections 326
A.3 FormatofAlgorithms 330
A.4 ConversiontoExistingProgrammingLanguages 332
B PracticalVectorsandMatrices 337
B.1 PointsandVectors 338
B.2 Matrices 347
B.3 Conclusion 353
Bibliography 357
Ludography 375
Index 377
xi
ListofFigures
1.1 Components,relationships,andaspectsofagame 2
1.2 Model,ViewandControllerinacomputergame 5
1.3 Basicdesignpartsofagame 6
1.4 Thephasesofagamedevelopmentproject 7
1.5 Gamedocuments 9
1.6 Storystructuresasgraphs 16
2.1 MonteCarlomethod 28
2.2 LasVegasmethod 28
2.3 Spectraltest 32
2.4 Spatialpointprocess 36
2.5 Riffleshuffle 40
2.6 Probabilitydistributionofaphantomdie 43
3.1 Twoperturbedsinefunctions 49
3.2 Visualizationofrandomnoisevalues 51
3.3 Agridofdistortedsquares 55
3.4 Simpleinterpolationfunctions 56
3.5 Simpleinterpolationoveranintegergrid 59
3.6 Twonoisecompositionmethods 61
3.7 Tilingwithaperiodicnoise 63
3.8 PhasesofaPerlinnoisegenerator 67
3.9 VariationsofPerlinnoiseonaplane 69
3.10 BasicWorleynoise 74
3.11 AdvancedWorleynoise 75
4.1 Heightmap 82
4.2 Randomlygeneratedterrains 83
4.3 Particledeposition 84
4.4 Faultline 86
4.5 Midpointdisplacement 88
4.6 Comparisonofalabyrinthandamaze 90
4.7 Asquareandhexagonalgridasagraph 90
4.8 Procedurallycreatedmazes 91
4.9 Fibonacciwordsasfractals 96
4.10 PlantcreatedwithanL-system 97
4.11 Roadpatterns 98
4.12 Creatingbuildingsbyextruding 99
xii ListofFigures
4.13 Enumeratingthepositionsofatwo-dimensionalgalaxy 99
4.14 Creatingthestarsystem 101
4.15 GenerationofnumbersinElite 104
5.1 Tournamentsforthesevenbrothers 106
5.2 Bracketforaneliminationtournament 114
5.3 Roundrobintournamentasacliquegraph 119
5.4 Matchesforaroundinaroundrobintournament 120
6.1 Partialgametreefornoughtsandcrosses 130
6.2 DivisionNimwithmatches 131
6.3 GametreeforDivisionNim 132
6.4 Evaluationfunctioninnoughtsandcrosses 135
6.5 Pruningthegametree 138
6.6 Alpha-betapruning 141
6.7 Gametreeforcoppernoughtsandcrosses 150
6.8 Gametreewiththreepossibleoutcomes 154
6.9 Gametreewithintegervalues 154
6.10 PartialgametreeforOne-Two-ThreeNim 155
6.11 PartialgametreeforNimwithheapsofsize1,2and3 156
6.12 n2-PileFlipflop 158
7.1 Reducingreal-worldpathfindingtoagraphproblem 160
7.2 Usingagridtoproducewaypoints 161
7.3 Squaregrid,triangulargrid,andhexagonalgrid 161
7.4 Connectivityinasquaregrid 162
7.5 Navigationmesh 162
7.6 Hertel–Mehlhornmethodforconvexpartition 163
7.7 Expandingtheverticesintheneighbourhood 164
7.8 Exampleofaheuristicfunction 166
7.9 ExampleofAlgorithmA* 168
7.10 Sharpandunrealisticturnsalongthepath 169
7.11 Improvingpathwithline-of-sighttesting 170
7.12 Avoidingdynamicobstacles 171
7.13 Monkey,boxandbanana 172
7.14 Gameworldasapolygon 173
7.15 Onesolutiontotheeight-queensproblem 173
7.16 Two-dimensionalgameworld 174
8.1 Humangroups 176
8.2 Steeringbehaviourrulesofflocking 177
8.3 Basicformationtypes 180
8.4 Formationsmodels 181
8.5 Strategiesforrealizingthemovementintotheformation 183
8.6 Zonesforcontrollingtheformation 184
8.7 Mass–springsystem 186
8.8 Aboxformationfacingacanyon 188
9.1 Decision-makingandpatternrecognition 190
9.2 Predictionandproduction 192
9.3 Optimization 193
9.4 Adaptation 195