Component Architecture in Computer Games

Introduction to the component architecture mainly used in computer games development.

Transcript

2. SINNERSCHRADER • Game Development: Brief History • Game Architecture: OO Approach • Game Architecture: Component Approach • Examples Agenda 2
3. Game Development Brief history
4. SINNERSCHRADER What are games? 4 Computer games are real-time interactive agent-based simulators....
5. SINNERSCHRADER Computer games are not applications 5 Emergence Gameplay Mechanics Usecases Interface Constraints
6. SINNERSCHRADER move_paddle ;read input from joystick lda joystick2;joy port 2 and #8 ;right beq move_paddle_right lda joystick2 and #4 ;#left beq move_paddle_left rts check_ball_paddle_collision lda sprite_collision and #2 cmp #2 beq ball_paddle_collision rts ball_paddle_collision lda sprite_collision and #2 sta sprite_collision ;clear collision bit jsr set_ball_direction_up rts 1986 BREAKOUT 6
7. SINNERSCHRADER 7 1993 DOOM bool P_CheckMissileRange (mobj_t* actor) { if (!P_CheckSight(actor, actor->target)) return false; // can’t see the target if (actor->reactiontime) return false; // do not attack yet dist = P_AproxDistance (actor, target) - 64*FRACUNIT; // no melee attack, so fire more if (!actor->info->meleestate) dist-=128*FRACUNIT; // check for ARCH-VILE if (actor->type == MT_VILE){ if (dist > 14*64) return false; // too far away } ...
8. SINNERSCHRADER 8 2017: Platformer 2D void OnTriggerEnter2D (Collider2D other) { // If the player enters the trigger zone... if(other.tag == "Player") { // Get a reference to the player health script. PlayerHealth playerHealth = other.GetComponent<PlayerHealth>(); playerHealth.health += healthBonus; // Trigger a new delivery. pickupSpawner.StartCoroutine( pickupSpawner.DeliverPickup()); // Destroy the crate. Destroy(transform.root.gameObject); } }
9. SINNERSCHRADER 9 Evolution of games
10. Game Architecture OO Approach
11. SINNERSCHRADER Example: Platformer 11
12. SINNERSCHRADER Game Model 12
13. SINNERSCHRADER Conclusion 13 Compile-time facilities aren’t appropriate for game development.
14. SINNERSCHRADER OO Approach 14 • simple • fast prototyping from scratch • low overhead • easy to debug • hard to maintain • hard to scale • not flexible • game objects may have features they don‘t need
15. Game Architecture Component Approach
16. SINNERSCHRADER Component 16 • Specified interfaces and explicit context dependencies • components are basically plug-and-play for objects • prefers composition over inheritance
17. SINNERSCHRADER • game object is just a container for data and logic • components communicate via messaging pattern Component Pattern 17
18. SINNERSCHRADER Messages example 18 • Game object added • Game object removed • Animation ended • Dragon hit • Enemy died • Player revived • Spell cast • Level completed • Game over
19. SINNERSCHRADER Conclusion 19 The overall behavior of a particular game object is determined by the aggregation of its components (and attributes).
20. SINNERSCHRADER Game Architecture 20 Every dynamic game must have an update loop and a scene. Game architecture is usually tightly coupled with a Scene Graph. 20
21. SINNERSCHRADER Example: Scene graph 21 21
22. SINNERSCHRADER Component example 22 class RotationAnim extends Component { oninit() { this.subscribe("STOP"); } onmessage(msg) { if (msg.action == "STOP") { this.finish(); } } update(delta, absolute) { this.owner.trans.rotation += delta; } }
23. Examples
24. SINNERSCHRADER Pacman 24
25. SINNERSCHRADER Pacman 25
26. SINNERSCHRADER Platformer 26
27. SINNERSCHRADER Platformer 27
28. SINNERSCHRADER Paratrooper clone 28
29. SINNERSCHRADER Paratrooper clone 29
30. SINNERSCHRADER Speed Driver 30
31. SINNERSCHRADER Speed Driver 31
32. SINNERSCHRADER Component Approach • scalable • data-oriented • easy to reuse components/behaviors • easy to make new object types • dynamic typing • all dependencies are to be linked together • hard to debug • messaging hell 32
33. SINNERSCHRADER Component-Oriented engines 33 • Artemis Framework (Java) • https://github.com/junkdog/artemis-odb • Atomic Game Engine (C++, C#, JS) • https://atomicgameengine.com/ • Unity (C#) • https://unity3d.com/ • My prototypes (JS, C++) • http://github.com/dodolibs
34. SINNERSCHRADER Questions? Tell uncle, if he gets a translator... ___________ | _ =| . | [_] / | | / _________ .| |________/ + + __/ o o o o \ .||. ______ooo__ooo___________________|________|__|__|__________|__|[]|_ 34