49 lines
1.8 KiB
GDScript
49 lines
1.8 KiB
GDScript
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## PathfindingHandler.gd
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# Handles A* pathfinding for the map using Godot's AStar2D.
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# Builds a navigation graph from walkable tiles and provides path queries.
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class_name PathfindingHandler
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extends RefCounted
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# All 8 possible neighbor offsets (cardinal and diagonal directions).
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const NEIGHBORS: Array[Vector2i] = [
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Vector2i.RIGHT, Vector2i.LEFT, Vector2i.DOWN, Vector2i.UP,
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Vector2i(1, 1), Vector2i(1, -1), Vector2i(-1, 1), Vector2i(-1, -1),
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]
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# The underlying AStar2D instance for pathfinding.
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var _astar: AStar2D = AStar2D.new()
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# Maps grid coordinates (Vector2i) to AStar2D point IDs.
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var _coord_to_id: Dictionary = {}
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# Builds the AStar2D graph from all walkable tiles in MapData.
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# Safe to call again for a new level — clears all previous state first.
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func build(data: MapData) -> void:
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_astar.clear()
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_coord_to_id.clear()
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# Register a point for every walkable tile (FLOOR).
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for coords: Vector2i in data.grid.keys():
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if data.grid[coords] == MapData.TileType.FLOOR:
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var id: int = _astar.get_available_point_id()
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_astar.add_point(id, Vector2(coords.x, coords.y))
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_coord_to_id[coords] = id
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# Connect each point to its walkable neighbors (cardinal and diagonal).
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for coords: Vector2i in _coord_to_id.keys():
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for offset: Vector2i in NEIGHBORS:
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var neighbor: Vector2i = coords + offset
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if _coord_to_id.has(neighbor):
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_astar.connect_points(_coord_to_id[coords], _coord_to_id[neighbor], false)
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# Returns the path as grid coordinates, or an empty array if no path exists.
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# Used by LevelManager and Player for navigation.
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func find_path(from: Vector2i, to: Vector2i) -> Array[Vector2i]:
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if not _coord_to_id.has(from) or not _coord_to_id.has(to):
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return []
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var raw: PackedVector2Array = _astar.get_point_path(_coord_to_id[from], _coord_to_id[to])
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var result: Array[Vector2i] = []
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for point in raw:
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result.append(Vector2i(point))
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return result
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