## Problem Design a game board that is conceptually infinite in all directions. Players and entities occupy cells on the grid. The board must support: ```python class InfiniteBoard: def place(self, entity_id: str, x: int, y: int) -> None: def move(self, entity_id: str, dx: int, dy: int) -> bool: # False if cell occupied def get_position(self, entity_id: str) -> tuple[int, int] | None: def get_entities_in_range(self, x: int, y: int, radius: int) -> list[str]: def get_neighbors(self, entity_id: str) -> list[str]: # adjacent 8 cells ``` ## Example ``` board.place("hero", 0, 0) board.place("goblin", 1, 0) board.move("hero", 1, 0) -> False # goblin is there board.move("goblin", 5, 5) board.move("hero", 1, 0) -> True # now clear board.get_entities_in_range(0, 0, 10) # -> ["hero", "goblin"] (goblin at (6,5) is within radius 10 of (0,0)) ``` ## Follow-ups 1. What data structure (hashmap, quadtree, spatial hash) is best for this use case? Under what entity densities? 2. How do you implement chunk-based loading as entities explore new areas? 3. How would you synchronize board state across multiple game server nodes?

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Infinite Board Game: Design a Sparse Infinite Grid Game World with Entity Tracking

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Problem Design a game board that is conceptually infinite in all directions. Players and entities occupy cells on the grid. The board must support: Example Follow-ups What data structure (hashmap, quadtree, spatial hash) is best for this use case? Under what entity densities? How do you implement chunk-based loading as entities explore new areas? How would you synchronize board state across multiple game server nodes?

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Infinite Board Game: Design a Sparse Infinite Grid Game World with Entity Tracking

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