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AStar2D

继承： RefCounted < Object

A* 的一种实现，用于查找 2D 空间中连通图上两个顶点之间的最短路径。

描述

A* 算法的一种实现，用于在 2D 空间中的连通图上找到两个顶点之间的最短路径。

有关如何使用该类的更详尽的解释，请参阅 AStar3D。AStar2D 是 AStar3D 的包装器，它强制执行 2D 坐标。

方法

float

_compute_cost(from_id: int, to_id: int) virtual const

float

_estimate_cost(from_id: int, end_id: int) virtual const

void

add_point(id: int, position: Vector2, weight_scale: float = 1.0)

bool

are_points_connected(id: int, to_id: int, bidirectional: bool = true) const

void

clear()

void

connect_points(id: int, to_id: int, bidirectional: bool = true)

void

disconnect_points(id: int, to_id: int, bidirectional: bool = true)

int

get_available_point_id() const

int

get_closest_point(to_position: Vector2, include_disabled: bool = false) const

Vector2

get_closest_position_in_segment(to_position: Vector2) const

PackedInt64Array

get_id_path(from_id: int, to_id: int, allow_partial_path: bool = false)

int

get_point_capacity() const

PackedInt64Array

get_point_connections(id: int)

int

get_point_count() const

PackedInt64Array

get_point_ids()

PackedVector2Array

get_point_path(from_id: int, to_id: int, allow_partial_path: bool = false)

Vector2

get_point_position(id: int) const

float

get_point_weight_scale(id: int) const

bool

has_point(id: int) const

bool

is_point_disabled(id: int) const

void

remove_point(id: int)

void

reserve_space(num_nodes: int)

void

set_point_disabled(id: int, disabled: bool = true)

void

set_point_position(id: int, position: Vector2)

void

set_point_weight_scale(id: int, weight_scale: float)

方法说明

float _compute_cost(from_id: int, to_id: int) virtual const 🔗

计算两个连接点之间的成本时调用。

请注意，这个函数在默认的 AStar2D 类中是隐藏的。

float _estimate_cost(from_id: int, end_id: int) virtual const 🔗

估算某个点和路径终点之间的成本时调用。

请注意，这个函数在默认的 AStar2D 类中是隐藏的。

void add_point(id: int, position: Vector2, weight_scale: float = 1.0) 🔗

在具有给定标识符的给定位置添加一个新点。id 必须为 0 或更大，weight_scale 必须为 0.0 或更大。

在确定从相邻点到此点的一段路程的总成本时，weight_scale 要乘以 _compute_cost 的结果。因此，在其他条件相同的情况下，算法优先选择 weight_scale 较低的点来形成路径。

var astar = AStar2D.new()
astar.add_point(1, Vector2(1, 0), 4) # 添加点 (1, 0)、权重为 4、ID 为 1

如果已经存在一个给定 id 的点，则它的位置和权重缩放将被更新为给定值。

bool are_points_connected(id: int, to_id: int, bidirectional: bool = true) const 🔗

返回两个给定点之间是否存在连接/线段。如果 bidirectional 为 false，则返回是否可以通过此段从 id 移动到 to_id。

void clear() 🔗

清除所有点和线段。

void connect_points(id: int, to_id: int, bidirectional: bool = true) 🔗

在给定的点之间创建一个线段。如果 bidirectional 为 false，则只允许从 id 到 to_id 的移动，而不允许反向移动。

var astar = AStar2D.new()
astar.add_point(1, Vector2(1, 1))
astar.add_point(2, Vector2(0, 5))
astar.connect_points(1, 2, false)

void disconnect_points(id: int, to_id: int, bidirectional: bool = true) 🔗

删除给定点之间的线段。如果 bidirectional 为 false，则仅阻止从 id 到 to_id 的移动，并且可能会保留一个单向线段。

int get_available_point_id() const 🔗

返回下一个没有关联点的可用点 ID。

int get_closest_point(to_position: Vector2, include_disabled: bool = false) const 🔗

返回距离 to_position 最近的点的 ID，可以选择将禁用的点考虑在内。如果点池中没有点，则返回 -1。

注意：如果有多个点距离 to_position 最近，则返回 ID 最小的那个点，以保证结果的确定性。

Vector2 get_closest_position_in_segment(to_position: Vector2) const 🔗

返回最接近 to_position 的位置，该位置位于两个连接点之间的线段内。

var astar = AStar2D.new()
astar.add_point(1, Vector2(0, 0))
astar.add_point(2, Vector2(0, 5))
astar.connect_points(1, 2)
var res = astar.get_closest_position_in_segment(Vector2(3, 3)) # 返回 (0, 3)

结果位于从 y = 0 到 y = 5 的线段中。它是线段中距给定点最近的位置。

PackedInt64Array get_id_path(from_id: int, to_id: int, allow_partial_path: bool = false) 🔗

Returns an array with the IDs of the points that form the path found by AStar2D between the given points. The array is ordered from the starting point to the ending point of the path.

If there is no valid path to the target, and allow_partial_path is true, returns a path to the point closest to the target that can be reached.

Note: When allow_partial_path is true and to_id is disabled the search may take an unusually long time to finish.

var astar = AStar2D.new()
astar.add_point(1, Vector2(0, 0))
astar.add_point(2, Vector2(0, 1), 1) # Default weight is 1
astar.add_point(3, Vector2(1, 1))
astar.add_point(4, Vector2(2, 0))

astar.connect_points(1, 2, false)
astar.connect_points(2, 3, false)
astar.connect_points(4, 3, false)
astar.connect_points(1, 4, false)

var res = astar.get_id_path(1, 3) # Returns [1, 2, 3]

If you change the 2nd point's weight to 3, then the result will be [1, 4, 3] instead, because now even though the distance is longer, it's "easier" to get through point 4 than through point 2.

int get_point_capacity() const 🔗

该函数返回支持点的数据结构的容量，可以与 reserve_space 方法一起使用。

PackedInt64Array get_point_connections(id: int) 🔗

返回一个数组，其中包含与给定点形成连接的点的 ID。

var astar = AStar2D.new()
astar.add_point(1, Vector2(0, 0))
astar.add_point(2, Vector2(0, 1))
astar.add_point(3, Vector2(1, 1))
astar.add_point(4, Vector2(2, 0))

astar.connect_points(1, 2, true)
astar.connect_points(1, 3, true)

var neighbors = astar.get_point_connections(1) # 返回 [2, 3]

int get_point_count() const 🔗

返回点池中当前的点数。

PackedInt64Array get_point_ids() 🔗

返回所有点 ID 的数组。

PackedVector2Array get_point_path(from_id: int, to_id: int, allow_partial_path: bool = false) 🔗

Returns an array with the points that are in the path found by AStar2D between the given points. The array is ordered from the starting point to the ending point of the path.

If there is no valid path to the target, and allow_partial_path is true, returns a path to the point closest to the target that can be reached.

Note: This method is not thread-safe. If called from a Thread, it will return an empty array and will print an error message.

Additionally, when allow_partial_path is true and to_id is disabled the search may take an unusually long time to finish.

Vector2 get_point_position(id: int) const 🔗

返回与给定 id 相关联的点的位置。

float get_point_weight_scale(id: int) const 🔗

返回与给定 id 关联的点的权重比例。

bool has_point(id: int) const 🔗

返回与给定 id 相关联的点是否存在。

bool is_point_disabled(id: int) const 🔗

返回用于寻路时点是否被禁用。默认情况下，所有点均被启用。

void remove_point(id: int) 🔗

从点池中移除与给定 id 关联的点。

void reserve_space(num_nodes: int) 🔗

Reserves space internally for num_nodes points. Useful if you're adding a known large number of points at once, such as points on a grid. The new capacity must be greater or equal to the old capacity.

void set_point_disabled(id: int, disabled: bool = true) 🔗

用于寻路时禁用或启用指定的点。适用于制作临时障碍物。

void set_point_position(id: int, position: Vector2) 🔗

为具有给定 id 的点设置位置 position。

void set_point_weight_scale(id: int, weight_scale: float) 🔗

为给定的 id 的点设置 weight_scale。在确定从邻接点到这个点的一段路程的总成本时，weight_scale 要乘以 _compute_cost 的结果。