SKILL.md
2D Game Development
Principles for 2D game systems.
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
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 |
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
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
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
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 |
Remember: 2D is about clarity. Every pixel should communicate.