2d-games

2D Game Development

Principles for 2D game systems. Pair with game-development/web-games / game-development/engine-selection for framework choice.

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Shell vs guest (web)

Setup	2D systems live…
Full-screen 2D game	Entire app (Phaser/Kaplay/Pixi/Canvas)
Hybrid DOM + challenges	Only inside guest viewports; tear down when done

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1. Sprite Systems

Component	Purpose
Atlas	Combine textures, reduce draw calls
Animation	Frame sequences (often 8-24 FPS)
Pivot	Rotation/scale origin
Layering	Z-order control

Animation Principles

• Squash and stretch for impact
• Anticipation before action
• Follow-through after action

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2. Tilemap Design

Factor	Recommendation
Size	16x16, 32x32, 64x64
Auto-tiling	Use for terrain
Collision	Simplified shapes

Layer	Content
Background	Non-interactive scenery
Terrain	Walkable ground
Props	Interactive objects
Foreground	Parallax overlay

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3. 2D Physics

Shape	Use Case
Box	Rectangular objects
Circle	Balls, rounded
Capsule	Characters
Polygon	Complex shapes

• Choose a movement/collision model per mechanic; pixel-art rendering can coexist with physics
• Fixed timestep for consistency
• Layers for filtering

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4. Camera Systems

Type	Use
Follow	Track player
Look-ahead	Anticipate movement
Multi-target	Two-player
Room-based	Metroidvania
Static	Board games, modal skill-checks

Screen Shake

• Short duration (50-200ms)
• Diminishing intensity
• Use sparingly

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5. Genre Patterns

Platformer

• Coyote time (leniency after edge)
• Jump buffering
• Variable jump height

Top-down

• 8-directional or free movement
• Aim-based or auto-aim
• Decide whether rotation matters

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6. Anti-Patterns

❌ Don't	✅ Do
Separate textures	Use atlases
Complex collision shapes	Simplified collision
Jittery camera	Smooth following
Uncoordinated movement and physics	Define one authority per body
Orphaned RAF/listeners after a guest closes	Full teardown

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Remember: 2D is about clarity. Every pixel should communicate.

When to Use

Use for canvas/Phaser/Kaplay/Pixi 2D systems, or guest viewports inside hybrid web apps.

Example

User request:

Add coyote time and jump buffering to our platformer while preserving the fixed physics timestep and testing corner collisions.

Limitations

• Use this skill only when the task clearly matches the scope described above.
• Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
• Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.