Using Lua to Build a Component-based Architecture for Game Apps

Presented on COSCUP 2013 http://coscup.org/2013/en/

Transcript

1. Using Lua to Build a
   Component-based
   Architecture for Game Apps
   半路 / Jheng Wei Ciao
   

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2. Component
   Based
   Architecture
   

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3. Lua
   

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4. Pitfalls of
   Object-Oriented Design
   ?!
   

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5. Traditional OOD
   Object-Oriented Design
   Class
   Inheritance
   Virtualization
   Polymorphism
   Inheritance-based Architecture
   

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6. Player Enemy
   WalkableObject
   Actor
   CollidableObject
   

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8. FlyableObject
   Player Enemy
   Actor
   WalkableObject
   CollidableObject
   

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9. CollidableObject FlyableObject
   FlyingEnemy
   Actor
   WalkableObject
   How?
   

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10. CollidableObject FlyableObject
    FlyingEnemy
    FlyingActor
    How?
    

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11. Pitfalls of IBA
    Deep and tangled hierarchies
    Diamond ring inheritance
    Copy-paste code here and there
    Special cases
    Magic: don’t touch it
    

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12. Component-based Architecture
    Each functionality is a game component
    Data-driven method for objects creation
    Design Patterns: “Favor composition over
    inheritance”
    

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13. Player
    WalkableObject
    CollidableObject
    FlyableObject
    Enemy
    WalkableObject
    CollidableObject
    FlyableObject
    

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14. WalkableObject
    CollidableObject
    FlyableObject
    Game
    Components
    

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15. WalkingEnemy
    FlyingEnemy
    WalkableObject
    CollidableObject CollidableObject
    FlyableObject
    

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16. Don’t use CBA... yet
    CBA can’t save your world
    OOD can do good things too
    Don’t make everything a component
    Leave messy code alone
    You might need an editor or tool
    

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18. Who Are Using Lua
    

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19. Advantages of Lua
    Lightweight
    Extensible
    Cross-platform
    Robust
    Openness
    Community
    

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20. Drawbacks of Lua
    Most editors don’t support auto-completion code
    Goodbye to debuggers & breakpoints
    Hello to loggers & print()
    No excuse for coffee break time
    

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21. Pitfalls of Lua
    Naming convention for global variables
    Do garbage collection manually
    Don’t forget to compile scripts & strip debug info
    

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22. My Lua Trilogy
    Lua
    5.1.5
    Luabind
    0.9.1
    Time-saver & OO-like
    Boost
    Luabind depends: template programming
    

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23. My Programming Trilogy
    C++
    Generic framework
    Objective-C
    iOS platform-specific
    OpenGL ES implementation
    Lua
    Data description
    Game logic
    10%
    65%
    25%
    C++ Lua Objectitve-C
    

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24. Player
    Transform
    BoundingBox
    Quad
    

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25. Meet Powerful ‘Table’
    Player = {}
    Player[“Transform”]
    Player[“Quad”]
    Player[“Transform”]:SetTranslate(50, 100)
    Player[“Quad”]:SetSize(120, 120)
    

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27. Traditional OOP
    Game Objects Update
    #1 #2 #3 #4 #5
    Game Objects Render
    #1 #2 #3 #4 #5
    

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28. Component-Based Architecture
    Game Components Update
    #1 #2 #3 #4 #5
    Game Components Render
    #1 #2 #3 #4 #5
    

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29. Game Object = Container
    Game Object
    Transform
    Bounding
    Sprite
    Motion
    StateMachine
    Timer
    

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30. Object Factory
    Game Component
    Templates
    Game Object
    Templates
    Game-based
    

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31. Interpolator GC
    0 255
    0.1 1.0
    SetAlpha()
    SetScale()
    

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32. Memory Management
    C++
    Transform
    Sprite
    ......
    Lua
    Game Object
    Transform
    Sprite
    

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33. User Interfaces & Widgets
    Widgets
    Button Picture
    Text Number
    Radio Button Progress Bar
    

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34. Widgets = Container
    Widgets
    Button
    Render/Update
    Movement
    Scale Up/Down
    Fade In/Out
    Sprite
    Motion
    Transform
    Fade
    

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35. MainMenu
    Button
    Sprite
    Interpolator
    Input Events
    

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36. Lua + CBA
    =
    100% Awesome!
    

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37. [Launching Xcode]
    Live Demo
    

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38. Live Game Apps?
    

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39. Lua for Game Apps
    

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40. CBA for Game Apps
    

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41. Lua + CBA ......?
    

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42. We’re recruiting one
    Android engineer
    

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43. Open Mind,
    Happy Coding,
    Make Great Games!
    

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