The document discusses using a component-based entity system architecture for developing a large mobile tower defense game with over 500 playable characters, complex item systems, and multiple game modes. A component-based entity system separates game objects into reusable components and uses independent processing systems, which makes the architecture easy to understand, maintain, and adapt to changing requirements. This fits well with a data-driven development approach using a database like MongoDB. The document recommends using an open-source entity system framework like Artemis and processing components in parallel threads to take advantage of the architecture.

1. Component-based
Entity System
in
Mobile Game Development
Cody Nguyen
(cody.haind@gmail.com)

3. GameArchitecture

5. Bigger project needs better architecture

7. What is
a good architecture?

8. A good architecture…
• Is easy to understand & maintain
• Welcomes changes
• Maximizes code reuse, minimizes duplication

9. Why doesVTT need
a good architecture?

10. Big game (dev-wise)
• Online tower defense, card collection on mobile

11. Big game (dev-wise)
• > 500 characters w/ different upgrade strategies

12. Big game (dev-wise)
• > 500 characters w/ different upgrade strategies

13. Big game (dev-wise)
• > 500 characters w/ different upgrade strategies

14. Big game (dev-wise)
• > 500 characters w/ different upgrade strategies

15. Big game (dev-wise)
• Complex items system: equip, enhance, forge

16. Big game (dev-wise)
• Complex items system: equip, enhance, forge

17. Big game (dev-wise)
• Complex items system: equip, enhance, forge

18. Big game (dev-wise)
• 8 game modes for the 500 characters to perform

19. Big game (dev-wise)
• 8 game modes for the 500 characters to perform

20. Big game (dev-wise)
• 8 game modes for the 500 characters to perform

21. Big game (dev-wise)
• 8 game modes for the 500 characters to perform

22. Big game (dev-wise)
• 8 game modes for the 500 characters to perform

23. Big game (dev-wise)
• 8 game modes for the 500 characters to perform

24. Game data & config need to be
human-friendly and easy to change
• Game designers & operators are lazy human beings
Anh Cody ơi
giảm base dam,
tăng máu cho
Thạch Sanh hộ
em
Tự vào admin panel
chỉnh đê!!!

25. Short on time, while requirements
change fast
• Reuse as much as possible
• Adapt to change

26. What is the most suitable
architecture forVTT?

27. OOP?
• Easy to understand
• Suitable for small project

28. Game objects usually share common (set of) functionalities
Bird Collision,Graphics,Animation,
TouchHandling
Pipe Collision,Graphics, Movement
Ground Collision,Graphics, Movement

29. Inheritance
Collidable
(Collision)
Pipe
Checkpoint
Renderable
Animatable
(Animation)
Bird
Movable
(Movement)
Pipe Ground

30. Inheritance
Collidable
(Collision)
Pipe
Checkpoint
Renderable
Animatable
(Animation)
Bird
Movable
(Movement)
Pipe Ground

31. Mixins or Multiple-inheritance. No!!!
Bird Pipe Ground
Collidable
(Collision)
Renderable
Animatable
(Animation)
Movable
(Movement)
Pipe
Checkpoint
Base Game
Object

32. It’s hard to create a good OO
architecture for bigger & more
complicated games
• Impossible to build a good OOP class hierachy
• Where to put logic code that process objects of 2+
different classes?
• Easy to make mistake when working in team

33. Component-based
entity system

34. Component-based Entity System
• A hot topics in recent years
• Unity3D is an example

35. Component-based Entity System
• Multitude of ways to
represent & implement

36. Component-based Entity System
3 components:
• Entity
• Component
• System

37. Entities – Components
Graphics Anim Move
Along Path
Attack Skill Collection
Bonus
Officer (defend) x x x x x
Officer (run) x x x
Soldier (defend) x x x
Soldier (run) x x x
Animal x x x
• Decompose game entities by capabilities into reusable components
– Components contains only data
– Each entity has an unique ID and a list of components
• Create entities by picking the desired components

38. Systems
• Divide game aspects into systems
• Systems process only entities they care about in each game loop
Move Along
Path Sys
Animation
Sys
Collection
Bonus Sys Attack Sys Skill Sys
Officer
(defend)
Officer (run)
Soldier
(defend)
Soldier (run) Animal

39. Entities – Components - Systems

40. Artemis Entity System
• An open-source Entity System Framework originally
written in Java
• Ported to many languages

41. Benefits

42. Goes hand-in-hand with
Data-Driven Methodology
• Components are just data, separated from game logic. Entities are just
bag of components
– Can be stored & retrieved from anywhere
– Human can make changes easily

43. MongoDB as database
• Flexible data structure, welcomes changes
• Easy synchronization between client / backend

44. Easy synchronization between client / backend

45. Easy synchronization between client / backend

46. Promote multi-threading
• Systems are independent from one another
-> can be run in separate threads

47. Conclusions
Online Game + Entity System = WIN

48. References
• A Data-DrivenGame Object System
http://scottbilas.com/files/2002/gdc_san_jose/game_objects_slides.ppt
• Entity Systems are the future of MMOG development
http://t-machine.org/index.php/2007/11/11/entity-systems-are-the-
future-of-mmog-development-part-2/
• EvolveYour Hierarchy
http://cowboyprogramming.com/2007/01/05/evolve-your-heirachy/
• http://gamedev.stackexchange.com/a/31491

49. THANKYOU!