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name: game-development description: Core game development principles applicable to all platforms. Game loop, design patterns, optimization, and AI fundamentals.

Game Development Fundamentals

Core principles for game development across all platforms. Learn to THINK, not memorize engine APIs.

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1. Game Loop Principles

The Universal Pattern

Every game has:
1. INPUT → Read player actions
2. UPDATE → Process game logic (fixed timestep)
3. RENDER → Draw the frame (interpolated)

Fixed Timestep Principle

• Physics/logic updates at fixed rate (e.g., 50Hz)
• Rendering runs as fast as possible
• Interpolate between states for smooth visuals

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2. Design Pattern Selection

When to Use Each Pattern

Pattern	Use When	Example
State Machine	Discrete states with transitions	Player: Idle→Walk→Jump→Attack
Object Pooling	Frequent create/destroy	Bullets, particles, enemies
Observer/Events	Decoupled communication	Health→UI, Death→Audio
ECS	Many similar entities	Thousands of units
Command	Replay, undo, networking	Input recording, multiplayer
Behavior Tree	Complex AI decisions	Enemy AI

Selection Principles

• Start simple (State Machine)
• Add ECS only if performance demands
• Use Events for cross-system communication
• Pool anything spawned frequently

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3. Core Systems Design

Input Abstraction

Abstract input into ACTIONS, not keys:
- "jump" → Space, Gamepad A, Touch tap
- "move" → WASD, Left stick, Virtual joystick

Benefits: Multi-platform, rebindable

Collision Strategy

Type	Best For
AABB	Rectangles, fast
Circle	Round objects, cheap
Spatial Hash	Many objects, same size
Quadtree	Large worlds, varying sizes

Save System

Platform	Storage
Web	LocalStorage, IndexedDB
Mobile	PlayerPrefs, FileAccess
PC	JSON/Binary files

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4. Performance Principles

Frame Budget (60 FPS = 16.67ms)

System	Budget
Input	1ms
Physics	3ms
AI	2ms
Game Logic	4ms
Rendering	5ms
Buffer	1.67ms

Optimization Priority

1. Algorithm - O(n²) to O(n log n)
2. Batching - Reduce draw calls
3. Pooling - Avoid GC spikes
4. LOD - Detail at distance
5. Culling - Don't render invisible

Memory Management

• Pool frequently spawned objects
• Use sprite atlases
• Stream large assets
• Unload unused resources

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5. AI Fundamentals

Selection by Complexity

AI Type	Complexity	Use Case
FSM	Simple	3-5 states, predictable
Behavior Tree	Medium	Modular, designer-friendly
GOAP	High	Emergent, planning
Utility AI	High	Scoring-based decisions

Common AI Behaviors

• Patrol → Move between waypoints
• Chase → Follow player
• Attack → Engage when in range
• Flee → Escape when low health

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6. Audio Principles

Audio Categories

Category	Behavior
Music	Loop, crossfade
SFX	One-shot, 3D positioned
UI	Immediate, no 3D
Voice	Priority, ducking

Best Practices

• Pool audio sources
• 3D audio for immersion
• Duck music during dialogue
• Preload frequently used sounds

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7. Anti-Patterns

❌ Don't	✅ Do
Update everything every frame	Use events, dirty flags
Create objects in hot loops	Object pooling
SELECT * in game logic	Cache references
Optimize without profiling	Profile first
Mix input with logic	Abstract input layer

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8. Sub-Skills Reference

Platform-specific guidance:

• PC Games → Engine selection, Steam
• Web Games → Phaser, Three.js, WebGPU
• Mobile Games → Touch, battery, stores
• Game Design → GDD, balancing
• Multiplayer → Networking patterns
• VR/AR → Immersion, comfort
• 2D Games → Sprites, tilemaps
• 3D Games → Meshes, shaders

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Remember: Great games come from iteration, not perfection. Prototype fast, then polish.