Game Development

1---
2name: game-development
3description: Game development orchestrator. Routes to platform-specific skills based on project needs.
4allowed-tools: Read, Write, Edit, Glob, Grep, Bash
5---
6 
7# Game Development
8 
9> **Orchestrator skill** that provides core principles and routes to specialized sub-skills.
10 
11---
12 
13## When to Use This Skill
14 
15You are working on a game development project. This skill teaches the PRINCIPLES of game development and directs you to the right sub-skill based on context.
16 
17---
18 
19## Sub-Skill Routing
20 
21### Platform Selection
22 
23| If the game targets... | Use Sub-Skill |
24|------------------------|---------------|
25| Web browsers (HTML5, WebGL) | `game-development/web-games` |
26| Mobile (iOS, Android) | `game-development/mobile-games` |
27| PC (Steam, Desktop) | `game-development/pc-games` |
28| VR/AR headsets | `game-development/vr-ar` |
29 
30### Dimension Selection
31 
32| If the game is... | Use Sub-Skill |
33|-------------------|---------------|
34| 2D (sprites, tilemaps) | `game-development/2d-games` |
35| 3D (meshes, shaders) | `game-development/3d-games` |
36 
37### Specialty Areas
38 
39| If you need... | Use Sub-Skill |
40|----------------|---------------|
41| GDD, balancing, player psychology | `game-development/game-design` |
42| Multiplayer, networking | `game-development/multiplayer` |
43| Visual style, asset pipeline, animation | `game-development/game-art` |
44| Sound design, music, adaptive audio | `game-development/game-audio` |
45 
46---
47 
48## Core Principles (All Platforms)
49 
50### 1. The Game Loop
51 
52Every game, regardless of platform, follows this pattern:
53 
54```
55INPUT  → Read player actions
56UPDATE → Process game logic (fixed timestep)
57RENDER → Draw the frame (interpolated)
58```
59 
60**Fixed Timestep Rule:**
61- Physics/logic: Fixed rate (e.g., 50Hz)
62- Rendering: As fast as possible
63- Interpolate between states for smooth visuals
64 
65---
66 
67### 2. Pattern Selection Matrix
68 
69| Pattern | Use When | Example |
70|---------|----------|---------|
71| **State Machine** | 3-5 discrete states | Player: Idle→Walk→Jump |
72| **Object Pooling** | Frequent spawn/destroy | Bullets, particles |
73| **Observer/Events** | Cross-system communication | Health→UI updates |
74| **ECS** | Thousands of similar entities | RTS units, particles |
75| **Command** | Undo, replay, networking | Input recording |
76| **Behavior Tree** | Complex AI decisions | Enemy AI |
77 
78**Decision Rule:** Start with State Machine. Add ECS only when performance demands.
79 
80---
81 
82### 3. Input Abstraction
83 
84Abstract input into ACTIONS, not raw keys:
85 
86```
87"jump"  → Space, Gamepad A, Touch tap
88"move"  → WASD, Left stick, Virtual joystick
89```
90 
91**Why:** Enables multi-platform, rebindable controls.
92 
93---
94 
95### 4. Performance Budget (60 FPS = 16.67ms)
96 
97| System | Budget |
98|--------|--------|
99| Input | 1ms |
100| Physics | 3ms |
101| AI | 2ms |
102| Game Logic | 4ms |
103| Rendering | 5ms |
104| Buffer | 1.67ms |
105 
106**Optimization Priority:**
1071. Algorithm (O(n²) → O(n log n))
1082. Batching (reduce draw calls)
1093. Pooling (avoid GC spikes)
1104. LOD (detail by distance)
1115. Culling (skip invisible)
112 
113---
114 
115### 5. AI Selection by Complexity
116 
117| AI Type | Complexity | Use When |
118|---------|------------|----------|
119| **FSM** | Simple | 3-5 states, predictable behavior |
120| **Behavior Tree** | Medium | Modular, designer-friendly |
121| **GOAP** | High | Emergent, planning-based |
122| **Utility AI** | High | Scoring-based decisions |
123 
124---
125 
126### 6. Collision Strategy
127 
128| Type | Best For |
129|------|----------|
130| **AABB** | Rectangles, fast checks |
131| **Circle** | Round objects, cheap |
132| **Spatial Hash** | Many similar-sized objects |
133| **Quadtree** | Large worlds, varying sizes |
134 
135---
136 
137## Anti-Patterns (Universal)
138 
139| Don't | Do |
140|-------|-----|
141| Update everything every frame | Use events, dirty flags |
142| Create objects in hot loops | Object pooling |
143| Cache nothing | Cache references |
144| Optimize without profiling | Profile first |
145| Mix input with logic | Abstract input layer |
146 
147---
148 
149## Routing Examples
150 
151### Example 1: "I want to make a browser-based 2D platformer"
152→ Start with `game-development/web-games` for framework selection
153→ Then `game-development/2d-games` for sprite/tilemap patterns
154→ Reference `game-development/game-design` for level design
155 
156### Example 2: "Mobile puzzle game for iOS and Android"
157→ Start with `game-development/mobile-games` for touch input and stores
158→ Use `game-development/game-design` for puzzle balancing
159 
160### Example 3: "Multiplayer VR shooter"
161→ `game-development/vr-ar` for comfort and immersion
162→ `game-development/3d-games` for rendering
163→ `game-development/multiplayer` for networking
164 
165---
166 
167> **Remember:** Great games come from iteration, not perfection. Prototype fast, then polish.
168