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+# Terrain & World
+
+> **Legend**
+> - ✅ Implemented — exists in the current codebase
+> - 🗺️ Planned — design exists but not yet implemented
+
+---
+
+## Tile Types ✅
+
+| Tile | ID | Passable | Notes |
+|------|----|----------|-------|
+| DEEP_WATER | 0 | No | |
+| SHALLOW_WATER | 1 | No | |
+| SAND | 2 | Yes | |
+| GRASS | 3 | Yes | Default terrain |
+| DARK_GRASS | 4 | Yes | After tree felled; reverts to GRASS after 5 min |
+| FOREST | 5 | No | Contains tree resource (70% spawn chance) |
+| ROCK | 6 | No | Contains rock resource (50% spawn chance) |
+| FLOOR | 7 | Yes | Built by player |
+| WALL | 8 | No | Built by player |
+| TILLED_SOIL | 9 | Yes | Ready for planting |
+| WATERED_SOIL | 10 | Yes | 2× crop growth speed |
+
+**Tile recovery:** DARK_GRASS → GRASS after **300,000 ms (5 min)**. Recovery is cancelled if a tree seedling is planted on the tile.
+
+---
+
+## World Constants ✅
+
+| Constant | Value |
+|----------|-------|
+| Tile size | 32 px |
+| World size | 512 × 512 tiles (16,384 × 16,384 px) |
+| Player speed | 180 px/s |
+| Camera lerp | 0.09 |
+| Autosave interval | 30,000 ms |
+
+---
+
+## Terrain Generation ✅
+
+- Generated procedurally via **Simplex noise** at world creation
+- World size: 512 × 512 tiles
+- FOREST tiles: **70%** chance to spawn a tree resource (HP 3)
+- ROCK tiles: **50%** chance to spawn a rock resource (HP 5)
+
+---
+
+← [[Game Systems Reference]]