AStar class representation that uses vectors as edges.
</brief_description>
<description>
A* (A star) is a computer algorithm that is widely used in pathfinding and graph traversal, the process of plotting an efficiently directed path between multiple points. It enjoys widespread use due to its performance and accuracy. Godot's A* implementation make use of vectors as points.
You must add points manually with [method AStar.add_point] and create segments manually with [method AStar.connect_points]. So you can test if there is a path between two points with the [method AStar.are_points_connected] function, get the list of existing ids in the found path with [method AStar.get_id_path], or the points list with [method AStar.get_point_path].
</description>
<tutorials>
</tutorials>
<demos>
</demos>
<methods>
<methodname="_compute_cost"qualifiers="virtual">
<returntype="void">
</return>
<argumentindex="0"name="from_id"type="int">
</argument>
<argumentindex="1"name="to_id"type="int">
</argument>
<description>
Called when computing the cost between two connected points.
</description>
</method>
<methodname="_estimate_cost"qualifiers="virtual">
<returntype="void">
</return>
<argumentindex="0"name="from_id"type="int">
</argument>
<argumentindex="1"name="to_id"type="int">
</argument>
<description>
Called when estimating the cost between a point and the path's ending point.
Adds a new point at the given position with the given identifier. The algorithm prefers points with lower [code]weight_scale[/code] to form a path. The [code]id[/code] must be 0 or larger, and the [code]weight_scale[/code] must be 1 or larger.
[codeblock]
var as = AStar.new()
as.add_point(1, Vector3(1,0,0), 4) # Adds the point (1,0,0) with weight_scale=4 and id=1
The result is in the segment that goes from [code]y=0[/code] to [code]y=5[/code]. It's the closest position in the segment to the given point.
</description>
</method>
<methodname="get_id_path">
<returntype="PoolIntArray">
</return>
<argumentindex="0"name="from_id"type="int">
</argument>
<argumentindex="1"name="to_id"type="int">
</argument>
<description>
Returns an array with the ids of the points that form the path found by AStar between the given points. The array is ordered from the starting point to the ending point of the path.
[codeblock]
var as = AStar.new()
as.add_point(1, Vector3(0,0,0))
as.add_point(2, Vector3(0,1,0), 1) # default weight is 1
as.add_point(3, Vector3(1,1,0))
as.add_point(4, Vector3(2,0,0))
as.connect_points(1, 2, false)
as.connect_points(2, 3, false)
as.connect_points(4, 3, false)
as.connect_points(1, 4, false)
as.connect_points(5, 4, false)
var res = as.get_id_path(1, 3) # returns [1, 2, 3]
[/codeblock]
If you change the 2nd point's weight to 3, then the result will be [code][1, 4, 3][/code] instead, because now even though the distance is longer, it's "easier" to get through point 4 than through point 2.
Returns an array with the points that are in the path found by AStar between the given points. The array is ordered from the starting point to the ending point of the path.
