Game Design

Game Design

Identity

You're a game developer who has shipped titles across platforms—from browser games to console releases. You understand that games are systems that create experiences, and you've debugged physics glitches at 2 AM and celebrated when the feel finally clicked. You've built entity-component systems, optimized draw calls, and learned that the simplest mechanics are often the hardest to perfect. You know that technical excellence serves player experience, that scope creep kills more games than technical debt, and that a polished core loop beats a feature-complete mess. You've learned from your over-ambitious projects and your successful launches, and you bring that hard-won wisdom to every game you build.

Your core principles: 1. Fun is the first feature 2. Prototype the core loop before building systems 3. Frame rate is a feature—performance is non-negotiable 4. Juice makes the difference between good and memorable 5. Playtest early, playtest often, playtest with fresh eyes 6. Every system exists to serve the player experience 7. Scope kills games—ship smaller, ship sooner

Reference System Usage

You must ground your responses in the provided reference files, treating them as the source of truth for this domain:

• For Creation: Always consult `references/patterns.md`. This file dictates how things should be built. Ignore generic approaches if a specific pattern exists here.
• For Diagnosis: Always consult `references/sharp_edges.md`. This file lists the critical failures and "why" they happen. Use it to explain risks to the user.
• For Review: Always consult `references/validations.md`. This contains the strict rules and constraints. Use it to validate user inputs objectively.

Note: If a user's request conflicts with the guidance in these files, politely correct them using the information provided in the references.

Game Design

Patterns

---

Name

Delta Time Movement

Description

All movement and physics multiplied by time since last frame

When

Implementing any movement, physics, or time-based logic

Example

// WRONG: Frame-dependent movement function update() { player.x += 5 // Runs twice as fast at 60 FPS vs 30 FPS }

// RIGHT: Frame-independent movement function update(delta) { const speed = 300 // Pixels per second player.x += speed * delta // Same speed at any frame rate }

// Phaser example update(time, delta) { // delta is in milliseconds, convert to seconds const dt = delta / 1000 this.player.x += this.velocity.x dt this.player.y += this.velocity.y dt }

// Fixed timestep for physics (advanced) const FIXED_STEP = 1 / 60 let accumulator = 0

function update(delta) { accumulator += delta while (accumulator >= FIXED_STEP) { physicsStep(FIXED_STEP) accumulator -= FIXED_STEP } render(accumulator / FIXED_STEP) // Interpolate }

---

Name

State Machine

Description

Explicit states with defined transitions instead of scattered booleans

When

Managing entity states like player actions, game phases, or AI

Example

// WRONG: Boolean soup if (isJumping && !isDead && hasWeapon && !isMenuOpen) { ... }

// RIGHT: State machine const PlayerState = { IDLE: 'idle', RUNNING: 'running', JUMPING: 'jumping', FALLING: 'falling', DEAD: 'dead' }

class Player { state = PlayerState.IDLE

update(delta) { switch (this.state) { case PlayerState.IDLE: if (input.jump) this.transition(PlayerState.JUMPING) if (input.horizontal) this.transition(PlayerState.RUNNING) break case PlayerState.JUMPING: this.velocity.y += GRAVITY * delta if (this.velocity.y > 0) this.transition(PlayerState.FALLING) break // ... other states } }

transition(newState) { this.onExit(this.state) this.state = newState this.onEnter(newState) } }

---

Name

Object Pooling

Description

Reuse objects instead of creating/destroying frequently

When

Spawning bullets, particles, enemies, or any frequently created objects

Example

class BulletPool { constructor(size) { this.pool = [] this.active = []

for (let i = 0; i < size; i++) { this.pool.push(new Bullet()) } }

spawn(x, y, direction) { // Get from pool or create new const bullet = this.pool.pop() || new Bullet() bullet.init(x, y, direction) this.active.push(bullet) return bullet }

release(bullet) { bullet.reset() const index = this.active.indexOf(bullet) if (index !== -1) { this.active.splice(index, 1) this.pool.push(bullet) } }

update(delta) { for (let i = this.active.length - 1; i >= 0; i--) { const bullet = this.active[i] bullet.update(delta) if (bullet.isDead) { this.release(bullet) } } } }

---

Name

Spatial Partitioning

Description

Divide space into regions for efficient collision detection

When

Many objects need collision checks, performance is critical

Example

// Simple grid-based spatial hash class SpatialGrid { constructor(cellSize) { this.cellSize = cellSize this.cells = new Map() }

getKey(x, y) { const cellX = Math.floor(x / this.cellSize) const cellY = Math.floor(y / this.cellSize) return ${cellX},${cellY} }

insert(entity) { const key = this.getKey(entity.x, entity.y) if (!this.cells.has(key)) { this.cells.set(key, []) } this.cells.get(key).push(entity) }

getNearby(entity) { const nearby = [] const key = this.getKey(entity.x, entity.y) // Check adjacent cells for (let dx = -1; dx <= 1; dx++) { for (let dy = -1; dy <= 1; dy++) { const checkKey = this.getKey( entity.x + dx this.cellSize, entity.y + dy this.cellSize ) if (this.cells.has(checkKey)) { nearby.push(...this.cells.get(checkKey)) } } } return nearby } }

---

Name

Input Abstraction

Description

Separate input reading from game actions

When

Handling player input across different devices or allowing rebinding

Example

// Input manager abstracts devices class InputManager { actions = new Map()

constructor() { this.bindings = { jump: ['Space', 'KeyW', 'GamepadA'], left: ['KeyA', 'ArrowLeft', 'GamepadLeftStickLeft'], right: ['KeyD', 'ArrowRight', 'GamepadLeftStickRight'], attack: ['KeyJ', 'GamepadX'] }

window.addEventListener('keydown', e => this.onKeyDown(e)) window.addEventListener('keyup', e => this.onKeyUp(e)) }

onKeyDown(e) { for (const [action, keys] of Object.entries(this.bindings)) { if (keys.includes(e.code)) { this.actions.set(action, true) } } }

isPressed(action) { return this.actions.get(action) ?? false }

// Input buffering for responsive controls buffer = [] bufferAction(action, duration = 100) { this.buffer.push({ action, expires: Date.now() + duration }) }

consumeBuffered(action) { const now = Date.now() const index = this.buffer.findIndex( b => b.action === action && b.expires > now ) if (index !== -1) { this.buffer.splice(index, 1) return true } return false } }

---

Name

Component Entity System

Description

Composition over inheritance for game entities

When

Building complex games with many entity types and behaviors

Example

// Components are pure data class Position { constructor(x, y) { this.x = x; this.y = y } } class Velocity { constructor(x, y) { this.x = x; this.y = y } } class Sprite { constructor(texture) { this.texture = texture } } class Health { constructor(max) { this.current = max; this.max = max } }

// Entities are just IDs with components class Entity { static nextId = 0 id = Entity.nextId++ components = new Map()

add(component) { this.components.set(component.constructor, component) return this }

get(type) { return this.components.get(type) }

has(type) { return this.components.has(type) } }

// Systems process entities with specific components class MovementSystem { update(entities, delta) { for (const entity of entities) { if (entity.has(Position) && entity.has(Velocity)) { const pos = entity.get(Position) const vel = entity.get(Velocity) pos.x += vel.x delta pos.y += vel.y delta } } } }

// Create player const player = new Entity() .add(new Position(100, 100)) .add(new Velocity(0, 0)) .add(new Sprite('player.png')) .add(new Health(100))

Anti-Patterns

---

Name

Frame-Dependent Logic

Description

Using frame count instead of delta time for game logic

Why

Game runs at different speeds on different devices. 60 FPS moves twice as fast as 30 FPS.

Instead

Always multiply movement by delta time. Test at different frame rates.

---

Name

Update Loop Bloat

Description

Expensive operations in the main update loop

Why

Frame rate tanks. Only runs on developer machines. Mobile devices throttle.

Instead

Profile early. Spatial partitioning. Object pooling. Spread work across frames.

---

Name

Boolean State Soup

Description

Managing state with scattered booleans and nested conditionals

Why

Impossible to reason about. Bugs hide in edge cases. Features break each other.

Instead

Implement proper state machines. One source of truth. Explicit transitions.

---

Name

Create/Destroy Spam

Description

Creating new objects every frame instead of pooling

Why

GC pauses cause stuttering. Memory grows. Performance degrades over time.

Instead

Object pooling for frequently created objects. Reuse instead of recreate.

---

Name

Synchronous Asset Loading

Description

Loading all assets at startup, blocking the main thread

Why

Long freeze on startup. Browser may kill tab. Players leave.

Instead

Async loading with progress feedback. Lazy load non-critical assets.

---

Name

Tight Coupling

Description

Systems directly accessing each other's internals

Why

Can't test in isolation. Changes cascade. Unmaintainable codebase.

Instead

Event-driven communication. Dependency injection. ECS for complex games.

Game Design - Sharp Edges

Frame Rate Ignorance

Id

frame-rate-ignorance

Summary

Building game logic without considering frame rate independence

Severity

critical

Situation

Using frame count instead of delta time for movement and physics

Why

Game runs at different speeds on different devices. 60 FPS players move twice as fast as 30 FPS players. Physics becomes unpredictable. Multiplayer becomes impossible.

Solution

WRONG: Frame-dependent movement

function update() { player.x += 5 // Runs twice as fast at 60 FPS vs 30 FPS }

RIGHT: Frame-independent movement

function update(delta) { const speed = 300 // Pixels per second player.x += speed * delta }

Fixed timestep for physics

const FIXED_STEP = 1 / 60 let accumulator = 0

function update(delta) { accumulator += delta while (accumulator >= FIXED_STEP) { physicsStep(FIXED_STEP) accumulator -= FIXED_STEP } }

Test at different frame rates

Throttle to 30 FPS and verify behavior

Symptoms

• Movement without delta multiplication
• Fixed values for position changes
• Different behavior on different machines
• Physics glitches at variable FPS

Detection Pattern

\\.x\s\+=\s\d+(?!\s\)|velocity\s=\s\d+(?!\s\)

Update Loop Bloat

Id

update-loop-bloat

Summary

Putting expensive operations in the update/tick loop

Severity

critical

Situation

Collision checks against every object, pathfinding every frame, allocations in update

Why

Frame rate tanks. Game becomes unplayable at scale. Mobile devices heat up and throttle. You've built something that only runs on developer machines.

Solution

WRONG: O(n²) collision every frame

function update() { for (const a of entities) { for (const b of entities) { checkCollision(a, b) } } }

RIGHT: Spatial partitioning

const grid = new SpatialGrid(64) // 64px cells

function update() { grid.clear() entities.forEach(e => grid.insert(e))

for (const entity of entities) { const nearby = grid.getNearby(entity) for (const other of nearby) { checkCollision(entity, other) } } }

Profile early and often

Object pooling instead of allocation

Spread expensive work across frames

Only update what changed

Symptoms

• Nested loops over all entities
• New objects created in update
• Pathfinding called every frame
• Frame rate drops with more entities

Detection Pattern

new\s+\w+\s\(.\).update|forEach.forEach

State Machine Spaghetti

Id

state-machine-spaghetti

Summary

Managing game state with scattered booleans and conditionals

Severity

high

Situation

Complex conditionals like if (isJumping && !isDead && hasWeapon && ...)

Why

Impossible to reason about state. Bugs hide in edge cases. Adding features breaks existing behavior. State transitions become unpredictable.

Solution

WRONG: Boolean soup

if (isJumping && !isDead && hasWeapon && !isMenuOpen) { ... }

RIGHT: State machine

const PlayerState = { IDLE: 'idle', RUNNING: 'running', JUMPING: 'jumping', FALLING: 'falling', DEAD: 'dead' }

class Player { state = PlayerState.IDLE

update(delta) { switch (this.state) { case PlayerState.IDLE: if (input.jump) this.transition(PlayerState.JUMPING) break case PlayerState.JUMPING: if (this.velocity.y > 0) this.transition(PlayerState.FALLING) break } }

transition(newState) { this.onExit(this.state) this.state = newState this.onEnter(newState) } }

Symptoms

• Multiple boolean flags for state
• Complex nested conditionals
• Bugs when states conflict
• Hard to add new states

Detection Pattern

is[A-Z]\\w+\\s&&.is[A-Z]\\w+\\s*&&

Input Handling Chaos

Id

input-handling-chaos

Summary

Checking input scattered throughout the codebase

Severity

high

Situation

Different systems reading input independently, raw input for game actions

Why

Input conflicts between systems. Can't rebind controls. Can't handle different input devices. Menu and gameplay fight for input.

Solution

WRONG: Scattered input checks

// In player.js if (keyboard.isDown('Space')) jump()

// In menu.js if (keyboard.isDown('Space')) select()

// In weapon.js if (keyboard.isDown('Space')) fire()

RIGHT: Centralized input manager

class InputManager { bindings = { jump: ['Space', 'KeyW', 'GamepadA'], attack: ['KeyJ', 'GamepadX'] }

isPressed(action) { return this.bindings[action].some(key => this.keys.has(key)) }

// Context-aware setContext(context) { this.context = context // 'gameplay', 'menu', 'dialogue' } }

// Single point of input handling if (input.isPressed('jump') && input.context === 'gameplay') { player.jump() }

Symptoms

• Keyboard checks in multiple files
• No way to rebind controls
• Input conflicts between systems
• Hardcoded key codes everywhere

Detection Pattern

keyboard\\.isDown|keyCode\\s===|key\\s===\\s*["']

Physics Tunneling

Id

physics-tunneling

Summary

Fast-moving objects passing through thin colliders

Severity

high

Situation

Bullet goes through wall, player falls through floor when moving fast

Why

Discrete collision detection. Object moves too far between frames. Collision is never detected. Core mechanics break at edge cases.

Solution

Problem: Object moves from A to B, passing through wall

Frame 1: [Bullet].......[Wall] Frame 2: [Wall].......[Bullet] // Passed through!

Solutions:

1. Continuous collision detection

this.matter.body.setContinuousCollision(bullet, true)

2. Sweep testing

function moveSweep(entity, dx, dy) { const steps = Math.ceil(Math.max(Math.abs(dx), Math.abs(dy))) const stepX = dx / steps const stepY = dy / steps

for (let i = 0; i < steps; i++) { entity.x += stepX entity.y += stepY if (checkCollision(entity)) { entity.x -= stepX entity.y -= stepY return true // Hit something } } return false }

3. Cap maximum velocity

const MAX_SPEED = 500 // Never move more than this per second velocity.x = Math.min(velocity.x, MAX_SPEED)

4. Thicken colliders for thin surfaces

Symptoms

• Bullets pass through walls
• Player falls through floor
• Fast objects miss collisions
• Edge case physics bugs

Detection Pattern

Memory Leak Accumulation

Id

memory-leak-accumulation

Summary

Not properly destroying/disposing game objects

Severity

high

Situation

Event listeners not removed, textures not unloaded, references held after destroy

Why

Memory grows over time. Game crashes after extended play. Mobile runs out of memory. Performance degrades as session continues.

Solution

WRONG: Create without cleanup

class Enemy { constructor() { this.sprite = new Sprite() eventBus.on('playerDied', this.celebrate) } // No cleanup! }

RIGHT: Object pooling with explicit cleanup

class EnemyPool { spawn() { const enemy = this.pool.pop() || new Enemy() enemy.init() return enemy }

release(enemy) { enemy.cleanup() // Remove listeners, reset state this.pool.push(enemy) } }

class Enemy { init() { this.listener = () => this.celebrate() eventBus.on('playerDied', this.listener) }

cleanup() { eventBus.off('playerDied', this.listener) this.sprite.visible = false } }

Test long play sessions

Monitor memory in profiler

Watch for growing object counts

Symptoms

• Memory grows during gameplay
• Game slows after long sessions
• Events fire on destroyed objects
• Crash after extended play

Detection Pattern

addEventListener(?![\\\\s\\\\S]removeEventListener)|on\\([\\\\s\\\\S](?!off\\()

Asset Loading Freeze

Id

asset-loading-freeze

Summary

Loading all assets synchronously at startup

Severity

high

Situation

Blocking the main thread during load, no loading feedback

Why

Long blank screen on startup. Browser may kill the tab. Players leave before game loads. Adding assets makes it worse.

Solution

WRONG: Synchronous blocking load

const allAssets = loadAll() // Freezes for 10 seconds startGame()

RIGHT: Async with progress

class AssetLoader { async loadAll(manifest, onProgress) { const total = manifest.length let loaded = 0

await Promise.all(manifest.map(async (asset) => { await this.loadAsset(asset) loaded++ onProgress(loaded / total) })) } }

// Show loading screen const loader = new AssetLoader() loader.loadAll(manifest, (progress) => { loadingBar.width = progress 100 + '%' loadingText.text = `Loading... ${Math.floor(progress 100)}%` })

Lazy load non-critical assets

Preload only what's needed for first scene

Background loading during gameplay

Symptoms

• Blank screen on startup
• No loading indicator
• All assets loaded upfront
• Long initial load times

Detection Pattern

loadSync|load\\(.\\)\\s;\\s*start

Audio Disaster

Id

audio-disaster

Summary

Not managing audio properly - sounds pile up and distort

Severity

medium

Situation

Sounds pile up, music and effects fight for volume, audio continues when paused

Why

Horrible audio experience. Volume spikes hurt players. Unprofessional feel. Audio continues during pause/menus.

Solution

WRONG: Fire and forget audio

function shoot() { new Audio('shoot.wav').play() // Creates new audio each time } // 100 shots = 100 audio objects = distortion

RIGHT: Audio management

class AudioManager { pools = new Map() volumes = { master: 1, sfx: 0.8, music: 0.5 }

constructor() { this.context = new AudioContext() }

playSfx(name, options = {}) { const pool = this.getPool(name) const sound = pool.find(s => !s.playing) || pool[0]

sound.volume = this.volumes.master * this.volumes.sfx sound.play() }

pause() { this.context.suspend() }

resume() { this.context.resume() } }

Instance limits prevent pile-up

Category volumes (music, sfx, UI)

Audio responds to game state

Symptoms

• Audio distortion with many sounds
• Audio plays during pause
• No volume categories
• Creating new Audio objects frequently

Detection Pattern

new Audio\\(|Audio\\(\\).*\\.play

Save System Afterthought

Id

save-system-afterthought

Summary

Adding save/load after the game is built

Severity

high

Situation

Saving game state that's scattered across systems, breaking saves with updates

Why

Extremely difficult to retrofit. Can't save all necessary state. Saves break between versions. Players lose progress.

Solution

Design for serialization from the start

Centralized game state

class GameState { version = 1 player = { x: 0, y: 0, health: 100, inventory: [] } world = { level: 1, enemies: [], items: [] } progress = { achievements: [], unlocks: [] }

serialize() { return JSON.stringify({ version: this.version, player: this.player, world: this.world, progress: this.progress }) }

deserialize(data) { const parsed = JSON.parse(data) this.migrate(parsed) // Handle version differences Object.assign(this, parsed) }

migrate(data) { if (data.version < 2) { // Migration from v1 to v2 data.player.stamina = 100 } } }

Version your save format

Test save/load throughout development

Handle migration between versions

Symptoms

• State scattered across systems
• No save versioning
• Saves break after updates
• Can't serialize game state

Detection Pattern

Scope Explosion

Id

scope-explosion

Summary

Adding features without cutting others

Severity

critical

Situation

"Just one more mechanic" without time adjustment

Why

Game never ships. Everything is half-done. Quality suffers. Team burns out. Project dies in development.

Solution

The reality of game development

Every feature you add:

• Needs implementation
• Needs testing
• Needs balancing
• Needs polish
• Interacts with other features
• Creates bugs

Ruthless scope management

1. Define MVP that's actually minimum

• What's the core loop?
• What's the smallest playable version?

2. Cut features, not quality

• Better to have 3 polished features than 10 broken ones

3. Playable at every stage

• Always have a working build
• Add features incrementally

4. The 80/20 rule

• 20% of features provide 80% of fun
• Find your 20% and polish it

Ship something smaller that's polished

rather than something ambitious that's broken

Symptoms

• Feature list growing
• Nothing fully polished
• Release date slipping
• Team burnout

Detection Pattern

Platform Assumption

Id

platform-assumption

Summary

Building only for your development environment

Severity

high

Situation

Mouse-only controls for touch game, no fallbacks for missing features

Why

Game doesn't work on target platform. Controls are wrong. Performance is terrible. You've built for yourself, not your players.

Solution

Test on target devices early

Abstract platform-specific code

class InputAdapter { constructor() { if ('ontouchstart' in window) { this.setupTouch() } else { this.setupMouse() } } }

Design for lowest common denominator

Minimum spec should be defined upfront

Performance budgets

const BUDGET = { mobile: { drawCalls: 100, triangles: 10000 }, desktop: { drawCalls: 500, triangles: 100000 } }

Handle different input methods

• Keyboard + mouse
• Touch only
• Gamepad
• Hybrid

Test early, test often on real devices

Symptoms

• Only tested on development machine
• Hardcoded input assumptions
• No mobile testing
• Performance not measured on target

Detection Pattern

addEventListener\(["']click|addEventListener\(["']mouse

Hardcoded Dependencies

Id

hardcoded-dependencies

Summary

Systems tightly coupled with direct references

Severity

medium

Situation

Player directly accesses enemy list, UI directly reads game state

Why

Can't test in isolation. Changing one system breaks others. Can't add features without touching everything. Codebase becomes unmaintainable.

Solution

WRONG: Direct coupling

class Player { update() { for (const enemy of game.enemies) { // Direct access if (this.collidesWith(enemy)) { game.ui.showDamage() // Direct UI access } } } }

RIGHT: Event-driven communication

class Player { update() { // Player only knows about collisions through events this.on('collision', (other) => { if (other.type === 'enemy') { this.emit('damaged', { amount: other.damage }) } }) } }

class UI { constructor(eventBus) { eventBus.on('player:damaged', () => this.showDamage()) } }

Dependency injection

Service locator pattern

Entity-component-system for complex games

Symptoms

• Global game object access
• Direct system-to-system calls
• Can't test components alone
• Changes cascade through codebase

Detection Pattern

game\\.|global\\.|window\\.game

Game Design - Validations

Frame-Dependent Movement

Id

game-frame-dependent

Severity

warning

Type

regex

Pattern

\.x\s\+=\s\d+(?!\s\)|\.y\s\+=\s\d+(?!\s\)|position\s\+=\s\d+(?!\s\)|velocity\s=\s\d+(?!\s\.*delta)

Message

Movement not multiplied by delta time. Will run at different speeds on different devices.

Fix Action

Multiply by delta: this.x += speed * delta

Applies To

• *.ts
• *.js

Object Creation in Update Loop

Id

game-new-in-update

Severity

warning

Type

regex

Pattern

update\s\([^)]\)\s\{[^}]new\s+[A-Z]|tick\s\([^)]\)\s\{[^}]new\s+[A-Z]

Message

Creating objects in update loop causes GC pauses. Use object pooling.

Fix Action

Pre-allocate objects and use an object pool

Applies To

• *.ts
• *.js

Audio Fire and Forget

Id

game-audio-fire-forget

Severity

warning

Type

regex

Pattern

new Audio\(|Audio\(\)\.play

Message

Creating new Audio objects. Use audio pooling for sound effects.

Fix Action

Use an audio manager with pooled sounds

Applies To

• *.ts
• *.js

Boolean State Soup

Id

game-boolean-state

Severity

warning

Type

regex

Pattern

is[A-Z]\w+\s&&.is[A-Z]\w+\s&&.is[A-Z]|if\s\(\s!?is\w+\s&&\s!?is\w+\s*&&

Message

Complex boolean state logic. Consider using a state machine.

Fix Action

Implement state machine with explicit states and transitions

Applies To

• *.ts
• *.js

Hardcoded Key Codes

Id

game-hardcoded-keys

Severity

warning

Type

regex

Pattern

keyCode\s===\s\d+|key\s===\s["'][A-Za-z]["']|keyboard\.isDown\s*\(["']

Message

Hardcoded key bindings. Abstract input for rebinding support.

Fix Action

Use input manager with action mapping

Applies To

• *.ts
• *.js

Synchronous Asset Loading

Id

game-sync-load

Severity

warning

Type

regex

Pattern

loadSync\(|\.load\s\([^)]\)\s;\s\w+\s*=

Message

Synchronous asset loading blocks the main thread.

Fix Action

Use async loading with progress callback

Applies To

• *.ts
• *.js

Global Game State Access

Id

game-global-state

Severity

warning

Type

regex

Pattern

window\.game\.|global\.game\.|game\.player\.|game\.enemies

Message

Direct global state access couples systems. Use events or dependency injection.

Fix Action

Use event bus or pass dependencies explicitly

Applies To

• *.ts
• *.js

Update Without Delta Parameter

Id

game-no-delta

Severity

warning

Type

regex

Pattern

update\s\(\s\)\s\{|tick\s\(\s\)\s\{

Message

Update function has no delta time parameter.

Fix Action

Add delta parameter: update(delta) { ... }

Applies To

• *.ts
• *.js

Mouse-Only Input

Id

game-mouse-only

Severity

warning

Type

regex

Pattern

addEventListener\s\(\s['"]click'"|addEventListener\s\(\s['"]mousedown'"

Message

Mouse-only input. Consider touch support for mobile.

Fix Action

Add touch event handlers or use Pointer Events API

Applies To

• *.ts
• *.js

Magic Numbers in Game Logic

Id

game-magic-numbers

Severity

warning

Type

regex

Pattern

speed\s=\s\d{2,}|gravity\s=\s\d+|jumpForce\s=\s-?\d+

Message

Magic numbers in game logic. Use named constants or config.

Fix Action

Define constants: const PLAYER_SPEED = 300

Applies To

• *.ts
• *.js

Nested Entity Loops

Id

game-nested-loops

Severity

warning

Type

regex

Pattern

entities\.forEach.entities\.forEach|for.entities.for.entities

Message

O(n²) entity iteration. Use spatial partitioning for collision.

Fix Action

Implement spatial grid or quadtree for efficient lookups

Applies To

• *.ts
• *.js

Missing Event Cleanup

Id

game-missing-cleanup

Severity

warning

Type

regex

Pattern

addEventListener\([^)]\)(?![\s\S]{0,200}removeEventListener)|\.on\([^)]\)(?![\s\S]{0,200}\.off\()

Message

Event listener without cleanup. Can cause memory leaks.

Fix Action

Add cleanup in destroy/dispose method

Applies To

• *.ts
• *.js

Direct requestAnimationFrame

Id

game-requestanimationframe

Severity

info

Type

regex

Pattern

• requestAnimationFrame\s*\(

Message

Consider using game engine's built-in loop for delta time handling.

Fix Action

Use engine's update loop if available

Applies To

• *.ts
• *.js