//重置导航数据信息
public void Reset()
{
open = true;
G = 0;
H = 0;
thisGrid = null;
preGrid = null;
}
//查看是否节点在列表中
private NavigationData Exits(List <NavigationData> list, GridUnitData target)
{
for (int i = 0; i < list.Count; ++i)
{
if (list[i].thisGrid == target)
{
return(list[i]);
}
}
return(null);
}
public MapData(int height, int width)
{
mapWidth = width;
mapHeight = height;
gridUnitDatas = new GridUnitData[mapHeight, mapWidth];
for (int i = 0; i < mapHeight; ++i)
{
for (int j = 0; j < mapWidth; ++j)
{
gridUnitDatas[i, j] = new GridUnitData(i, j);
}
}
}
//获取目标的所有可到达的相邻节点
public List <GridUnitData> GetNeighbor(GridUnitData target)
{
//定义方向数组
int[] dx = { 0, 1, 0, -1 };
int[] dy = { 1, 0, -1, 0 };
List <GridUnitData> neighbor = new List <GridUnitData>();
for (int i = 0; i < 4; ++i)
{
int x = target.row + dx[i], y = target.column + dy[i];
//越界或者是障碍则跳过
if (x < 0 || x >= mapHeight || y < 0 || y >= mapWidth || gridUnitDatas[x, y].gridType == GridType.Obstacle)
{
continue;
}
neighbor.Add(gridUnitDatas[x, y]);
}
return(neighbor);
}
//取空的导航数据
private NavigationData GetEmptyNavigationData(GridUnitData thisGrid, NavigationData preGrid, int G, int H)
{
//优先从池中取
NavigationData nd = null;
if (curUsedIdx < navigationDataPool.Count)
{
nd = navigationDataPool[curUsedIdx];
}
else
{
nd = new NavigationData();
navigationDataPool.Add(nd);
}
++curUsedIdx;
nd.open = true;
nd.G = G;
nd.H = H;
nd.thisGrid = thisGrid;
nd.preGrid = preGrid;
return(nd);
}
//该单元格到目标单元格的曼哈顿距离
public int Distance(GridUnitData target)
{
return(Mathf.Abs(row - target.row) + Mathf.Abs(column - target.column));
}
///<summary>
///导航
///</summary>
///<param name="mapData">地图数据</param>
///<param name="from">起点</param>
///<param name="to">终点</param>
///<param name="path">路径</param>
///<param name="searched">搜索过但为采用的节点</param>
public bool Navigate(MapData mapData, GridUnitData from, GridUnitData to, out List <GridUnitData> path, out List <GridUnitData> searched)
{
//输出参数赋初值
path = new List <GridUnitData>();
searched = new List <GridUnitData>();
//没有地图则结束导航
if (mapData == null)
{
Debug.Log("mapData is null!");
return(false);
}
if (from == null || to == null)
{
Debug.Log("from or to is null!");
return(false);
}
//open储存将要探索的节点
List <NavigationData> open = new List <NavigationData>();
//close储存已经探索的节点
List <NavigationData> close = new List <NavigationData>();
//1.把起点加入open
open.Add(GetEmptyNavigationData(from, null, 0, from.Distance(to)));
int trytimes = 999;
while (trytimes-- != 0)
{
//2.判断open列表,如果为空则搜索失败,如果终点在里面则搜索成功
if (open.Count == 0)
{
return(false);
}
NavigationData temp = Exits(open, to);
if (temp != null)
{
//从终点回溯至起点
while (temp != null)
{
path.Add(temp.thisGrid);
temp = temp.preGrid;
}
for (int i = 0; i < close.Count; ++i)
{
searched.Add(close[i].thisGrid);
}
return(true);
}
//3.从open列表取出F值最小的节点,将其设为当前节点,并加入close列表中
NavigationData nowGrid = open[0];
int minF = open[0].F, minH = open[0].H;
for (int i = 1; i < open.Count; ++i)
{
if (open[i].F < minF || (open[i].F == minF && open[i].H < minH))
{
nowGrid = open[i];
minF = open[i].F;
minH = open[i].H;
}
}
close.Add(nowGrid);
open.Remove(nowGrid);
//Debug.Log(nowGrid.thisGrid.row + "|" + nowGrid.thisGrid.column + " " + nowGrid.G + ',' + nowGrid.H + ',' + nowGrid.F);
//4.获取当前节点的所有可到达节点
List <GridUnitData> neighbor = mapData.GetNeighbor(nowGrid.thisGrid);
//对于每个节点
for (int i = 0; i < neighbor.Count; ++i)
{
//4.1 如果该节点在close列表中,删除open中的该节点
NavigationData t = Exits(close, neighbor[i]);
if (t != null)
{
open.Remove(t);
continue;
}
t = Exits(open, neighbor[i]);
//int G = from.Distance(neighbor[i]);
int G = nowGrid.G + 1;
int H = to.Distance(neighbor[i]);
//4.2 如果该节点不在open中,计算G,H值,设置父节点为当前节点,加入open列表
if (t == null)
{
NavigationData target = GetEmptyNavigationData(neighbor[i], nowGrid, G, H);
open.Add(target);
}
//4.3 如果该节点在open中且以当前节点求F值更小,则更新G,H,设父节点为当前节点
else if (t.F > G + H)
{
t.G = G;
t.H = H;
t.preGrid = nowGrid;
}
}
}
return(false);
}
