// 发现一个新点
public void GetDataFrom(PathNode center, PathNode end, HeuristicsDelegate func)
{
float deltaG = func(this.coord, center.coord);
g = center.g + deltaG;
h = func(this.coord, end.coord);
parent = center;
}
/// <summary>
/// 是否需要更新 center 为新的 parent
/// </summary>
/// <param name="center"></param>
/// <param name="func"></param>
public void UpdateFrom(PathNode center, HeuristicsDelegate func)
{
float deltaG = func(this.coord, center.coord);
float newG = center.g + deltaG;
if (newG < g)
{
parent = center;
g = newG;
}
}
/// <summary>
/// 寻路主算法
/// </summary>
/// <param name="mesh">寻路网格</param>
/// <param name="start">开始结点</param>
/// <param name="end">结束结点</param>
/// <param name="hType">启发函数类型</param>
/// <param name="allowDiagonal">允许走对角线</param>
/// <param name="hightLimit">高度限制</param>
/// <returns></returns>
public static List <PathNode> FindPath(NodeMesh mesh, PathNode start, PathNode end, HeuristicsType hType, bool allowDiagonal, int hightLimit = 0)
{
if (!mesh.Exists(start) || !mesh.Exists(end))
{
return(null);
}
HeuristicsDelegate hFunc = Heuristics.HeuristicsFactory(hType);
openList.Clear();
closeList.Clear();
// 算法
PathNode current;
openList.Add(start);
bool canReach = false;
// 循环处理开放节点列表(边界)
while (openList.Count > 0)
{
current = openList.OrderBy(n => n.f).First();
if (current.Equals(end))
{
canReach = true;
break;
}
openList.Remove(current);
closeList.Add(current);
// 获取相邻节点
List <PathNode> neighbours = mesh.GetNeighbour(current, allowDiagonal);
// 遍历处理邻居节点
foreach (PathNode nb in neighbours)
{
// 已经在关闭列表则跳过
if (!CanMoveTo(current, nb, hightLimit))
{
continue;
}
if (closeList.IndexOf(nb) > -1)
{
continue;
}
// 在开放列表(检测边界)
if (openList.IndexOf(nb) > -1) // nb在open列表中
// 检测,是否需要 (更新G值,设置parent为current)
{
nb.UpdateFrom(current, hFunc);
}
else
{
// 计算H 和parent和G// 新出现的节点
nb.GetDataFrom(current, end, hFunc);
openList.Add(nb);
}
}
}
if (!canReach)
{
return(null);
}
current = end;
List <PathNode> result = new List <PathNode>();
while (current.parent != null)
{
result.Add(current);
current = current.parent;
}
return(result);
}
