# Game Development Decisions

Decision frameworks for technical and design choices in game development.

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## 1. Game Engine Selection

**Context**: Choosing the right engine for your project.

| Option | When to Choose | Trade-offs |
|--------|----------------|------------|
| **Phaser/PixiJS (Web)** | Browser-based, 2D, rapid iteration, web distribution | Web-only, limited 3D, performance ceiling |
| **Unity** | Cross-platform, 2D or 3D, large asset store, C# | Engine complexity, licensing costs, mobile build size |
| **Godot** | Open source, 2D or 3D, integrated tools, GDScript | Smaller community, less asset store, newer |
| **Unreal** | AAA 3D, visual quality, C++/Blueprints | Steep learning curve, heavy, royalty on revenue |
| **Custom** | Unique requirements, learning exercise, full control | Massive time investment, reinventing wheels |

**Decision criteria**: Platform target, team experience, project scope, budget, timeline.

**Red flags**: Unity for a simple web game, custom engine for first project, Unreal for a 2D mobile game.

---

## 2. Rendering Approach (2D)

**Context**: How to render your 2D game graphics.

| Option | When to Choose | Trade-offs |
|--------|----------------|------------|
| **Sprite-based** | Traditional 2D, pixel art, tile-based games | Limited animation smoothness, texture memory |
| **Spine/skeletal** | Complex character animation, smooth motion | Learning curve, tool cost, setup time |
| **Vector-based** | Resolution-independent, clean style | Limited detail, different art pipeline |
| **Hybrid** | Different needs for different elements | Complexity, inconsistent style risk |

**Decision criteria**: Art style, animation complexity, target resolution, team skills.

**Red flags**: Skeletal animation for pixel art, vector graphics for retro aesthetic, mismatched approaches.

---

## 3. Physics Engine Usage

**Context**: Whether and how to use a physics engine.

| Option | When to Choose | Trade-offs |
|--------|----------------|------------|
| **Full physics engine** | Realistic physics core to gameplay, emergent behavior | Complex, hard to tune, CPU intensive |
| **Lightweight physics** | Basic collision, simple gravity, platformer | Less emergent, more predictable, manual work |
| **No physics (manual)** | Simple game, full control needed, specific feel | Implement everything, miss edge cases |
| **Hybrid** | Physics for some, manual for critical interactions | Complexity, inconsistent feel |

**Decision criteria**: Core mechanics, feel requirements, performance budget, complexity tolerance.

**Red flags**: Full physics for a puzzle game, no physics for a physics-based puzzler, Box2D for simple tile collision.

---

## 4. Entity Architecture

**Context**: How to structure game objects and their behavior.

| Option | When to Choose | Trade-offs |
|--------|----------------|------------|
| **Object-oriented (inheritance)** | Small games, few entity types, simple behavior | Inheritance problems at scale, inflexible |
| **Component-based** | Many entity types, flexible combinations, medium complexity | More setup, component management |
| **Entity-Component-System (ECS)** | Large entity counts, performance critical, complex games | Learning curve, overengineering risk, framework dependency |
| **Hybrid** | Different needs in different systems | Inconsistency, context-switching |

**Decision criteria**: Game complexity, entity count, team experience, performance requirements.

**Red flags**: ECS for a simple puzzle game, deep inheritance for a complex RPG, premature architecture decisions.

---

## 5. Multiplayer Architecture

**Context**: How to structure networked multiplayer (if needed).

| Option | When to Choose | Trade-offs |
|--------|----------------|------------|
| **Peer-to-peer** | Small player count, LAN focus, simple game | Cheating vulnerability, NAT issues, host advantage |
| **Authoritative server** | Competitive, cheat prevention matters, any scale | Server costs, complexity, latency sensitivity |
| **Rollback netcode** | Fighting games, precision timing, twitch gameplay | Complex implementation, CPU overhead |
| **Turn-based async** | Strategy, mobile, not time-sensitive | Limited game types, less "multiplayer feel" |

**Decision criteria**: Game type, competitive stakes, player count, budget for infrastructure.

**Red flags**: P2P for competitive ranked, authoritative server without infrastructure budget, rollback without expertise.

---

## 6. Save System Approach

**Context**: How to persist and restore game state.

| Option | When to Choose | Trade-offs |
|--------|----------------|------------|
| **Single save slot** | Simple game, short sessions, no save management | Limited player choice, potential loss |
| **Multiple slots (local)** | Longer game, player-managed saves | UI complexity, storage management |
| **Cloud saves** | Cross-device, persistent, account-based | Infrastructure needed, sync conflicts |
| **Checkpoint only** | Action games, designed challenge, no quicksave | Less player control, potential frustration |

**Decision criteria**: Game length, player expectations, platform capabilities, game design.

**Red flags**: No saves for a long RPG, cloud saves without conflict resolution, checkpoint systems that are too far apart.

---

## 7. Audio Implementation

**Context**: How to handle game audio.

| Option | When to Choose | Trade-offs |
|--------|----------------|------------|
| **Web Audio API (direct)** | Simple needs, web-only, few sounds | Limited features, manual management |
| **Howler.js / similar** | Web games, moderate complexity | Dependency, but solves common problems |
| **FMOD / Wwise** | AAA audio, complex soundscapes, native | Learning curve, cost, integration complexity |
| **Engine built-in** | Using Unity/Godot, typical needs | Good enough for most, less control |

**Decision criteria**: Audio complexity, platform, budget, team audio expertise.

**Red flags**: FMOD for a web puzzle game, raw Web Audio for complex spatial audio, ignoring audio until late.

---

## 8. Input Handling Strategy

**Context**: How to manage player input.

| Option | When to Choose | Trade-offs |
|--------|----------------|------------|
| **Direct polling** | Simple games, single input method | Platform coupling, no rebinding |
| **Event-based** | UI-heavy, modern engine, responsive | Can miss held states, timing nuance |
| **Action-mapped** | Multiple control schemes, rebinding, gamepad support | More setup, abstraction overhead |
| **Input buffering** | Fighting games, precise timing, combo systems | Complexity, timing tuning |

**Decision criteria**: Game genre, platform targets, control complexity, accessibility needs.

**Red flags**: Direct polling for cross-platform, no rebinding for accessibility, complex buffer for simple game.

---

## 9. Level/Content Structure

**Context**: How to organize and load game content.

| Option | When to Choose | Trade-offs |
|--------|----------------|------------|
| **Hardcoded levels** | Simple game, few levels, rapid iteration | Can't modify without code, limited content |
| **Data-driven (JSON/XML)** | Many levels, designer-editable, moddable | Parsing complexity, validation needed |
| **Editor-generated (Tiled, LDTK)** | Visual editing, tilemap-based | Tool dependency, learning curve |
| **Procedural** | Roguelikes, infinite content, emergent | Less handcrafted feel, quality variance |

**Decision criteria**: Content volume, team structure, game genre, moddability needs.

**Red flags**: Hardcoded for content-heavy games, procedural for story-focused, complex editors for few levels.

---

## 10. Performance Optimization Priority

**Context**: Where to focus optimization efforts.

| Option | When to Choose | Trade-offs |
|--------|----------------|------------|
| **Rendering** | Draw call heavy, complex scenes, GPU bottleneck | May not be actual bottleneck |
| **Physics/collision** | Many entities, complex physics, CPU spike on collision | Spatial structure changes required |
| **Memory/GC** | Frame spikes, mobile, long sessions | May require architecture changes |
| **Loading/streaming** | Large worlds, many assets, long load times | Async complexity, streaming logic |

**Decision criteria**: Profile data (not guesses), platform constraints, player-visible impact.

**Red flags**: Optimizing without profiling, assuming bottleneck location, premature optimization, ignoring the actual problem.
