boisenoise/2d-games

2D Game Development

Principles for 2D game systems.

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1. Sprite Systems

Sprite Organization

| Component | Purpose | |-----------|---------| | Atlas | Combine textures, reduce draw calls | | Animation | Frame sequences | | Pivot | Rotation/scale origin | | Layering | Z-order control |

Animation Principles

• Frame rate: 8-24 FPS typical
• Squash and stretch for impact
• Anticipation before action
• Follow-through after action

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2. Tilemap Design

Tile Considerations

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

Layers

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

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3. 2D Physics

Collision Shapes

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

Physics Considerations

• Pixel-perfect vs physics-based
• Fixed timestep for consistency
• Layers for filtering

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4. Camera Systems

Camera Types

| Type | Use | |------|-----| | Follow | Track player | | Look-ahead | Anticipate movement | | Multi-target | Two-player | | Room-based | Metroidvania |

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
• Consider rotation or not

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6. Anti-Patterns

| ❌ Don't | ✅ Do | |----------|-------| | Separate textures | Use atlases | | Complex collision shapes | Simplified collision | | Jittery camera | Smooth following | | Pixel-perfect on physics | Choose one approach |

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

When to Use

This skill is applicable to execute the workflow or actions described in the overview.

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.