public bool init(IAStarGraph graph)
{
if (graph == null)
{
return(false);
}
mGraph = graph;
mFValues = new float[mGraph.getCellCount()];
mGValues = new float[mGraph.getCellCount()];
mOpenTable = new uint[mGraph.getCellCount()];
mCloseTable = new uint[mGraph.getCellCount()];
mShortestPathTree = new uint[mGraph.getCellCount()];
for (int i = 0; i < mGraph.getCellCount(); i++)
{
mFValues[i] = 0.0f;
mGValues[i] = 0.0f;
mOpenTable[i] = 0;
mCloseTable[i] = 0;
mShortestPathTree[i] = 0;
}
mPriorityQueue.Init(mFValues);
mSessionId = 0;
return(true);
}
/// <summary>
/// 获取一条路径
/// </summary>
/// <param name="graph">节点关系图</param>
/// <param name="from">起点</param>
/// <param name="to">终点</param>
/// <returns>如果没有找到路径返回NULL</returns>
public static List <AStarNode> FindPath(IAStarGraph graph, AStarNode from, AStarNode to)
{
// 清空上次寻路数据
graph.ClearTemper();
_openList.Clear();
_closedList.Clear();
// 开始寻找路径
_openList.Add(from);
while (_openList.Count > 0)
{
// 获取当前代价值最小的节点
AStarNode current = _openList[0];
for (int i = 1; i < _openList.Count; i++)
{
if (_openList[i].Cost < current.Cost)
{
current = _openList[i];
}
}
_openList.Remove(current);
_closedList.Add(current);
// 成功找到终点
if (current == to)
{
return(RetracePath(from, to));
}
// 获取邻居节点并添加到开放列表
foreach (AStarNode neighbor in graph.Neighbors(current))
{
if (neighbor == null || neighbor.IsBlock() || _closedList.Contains(neighbor))
{
continue;
}
float newCostToNeighbor = current.G + graph.CalculateCost(current, neighbor);
if (newCostToNeighbor < neighbor.G || _openList.Contains(neighbor) == false)
{
neighbor.G = newCostToNeighbor;
neighbor.H = graph.CalculateCost(neighbor, to);
neighbor.Parent = current;
if (_openList.Contains(neighbor) == false)
{
_openList.Add(neighbor);
}
}
}
}
// 没有找到路径
return(null);
}
