/// <summary>
/// 比较两个节点的F值
/// </summary>
/// <param name="x">第一个节点</param>
/// <param name="y">第二个节点</param>
/// <returns></returns>
private int Compare(PathNote x, PathNote y)
{
if (x.F > y.F)
{
return(1);
}
else if (x.F < y.F)
{
return(-1);
}
return(0);
}
/// <summary>
/// 组织传入的PathNote的所有父节点为List
/// </summary>
/// <param name="pathNote">PathNote</param>
/// <param name="pathPoints">列表</param>
/// <returns>路径</returns>
private List <Point> GetPointListByParent(PathNote pathNote, List <Point> pathPoints)
{
if (pathPoints == null)
{
pathPoints = new List <Point>();
}
if (pathNote.parentNote != null)
{
pathPoints.Add(new Point(pathNote.parentNote.X, pathNote.parentNote.Y));
GetPointListByParent(pathNote.parentNote, pathPoints);
}
return(pathPoints);
}
/// <summary>
/// 开始寻找路径
/// </summary>
/// <returns></returns>
public List<Point> StartFindPath()
{
var found = false;
var pathNote = new PathNote() { F = 0, G = 0, H = 0, X = (int)startPoint.X, Y = (int)startPoint.Y, parentNote = null };
List<Point> resultPoints = null;
while (true)
{
for (int i = 0; i < (diagonals ? 8 : 4); i++) //找到pathNote四方向或八方向周围节点,取F值最小的那个继续此过程
{
var x = pathNote.X + direction[i, 0];
var y = pathNote.Y + direction[i, 1];
if (x < 0 || y < 0 || x > matrix.GetUpperBound(0) || y > matrix.GetUpperBound(1)) //坐标过界
continue;
var newPathNote = new PathNote();
newPathNote.parentNote = pathNote;
newPathNote.X = x;
newPathNote.Y = y;
bool isClosed = false;
bool isOpened = false;
PathNote theOpendandSameNote = null;
foreach (var closedNote in colsedList)
{
if (closedNote.X == newPathNote.X && closedNote.Y == newPathNote.Y)
{
isClosed = true; //节点已经在关闭列表中
}
}
foreach (var openedNote in openedList)
{
if (openedNote.X == newPathNote.X && openedNote.Y == newPathNote.Y)
{
isOpened = true; //节点已经在开启列表中,稍后比较两条路径
theOpendandSameNote = openedNote;
}
}
if (matrix[newPathNote.X, newPathNote.Y] != 0 || isClosed) //不能通行或者已经在关闭列表中存在
continue;
if (Math.Abs(direction[i, 0] + direction[i, 1]) == 2) //G值
{
newPathNote.G = newPathNote.parentNote.G + 14;
}
else
{
newPathNote.G = newPathNote.parentNote.G + 10;
}
newPathNote.H = (int)(Math.Abs(endPoint.X - newPathNote.X) + Math.Abs(endPoint.Y - newPathNote.Y)) * 10; //H值
newPathNote.F = newPathNote.G + newPathNote.H; //F值
if (isOpened) //比较已在开启列表中的节点G值和准备创建的节点G值
{
if (newPathNote.G >= theOpendandSameNote.G)
{
this.openedList.Remove(pathNote);
continue;
}
else
{
this.openedList.Remove(theOpendandSameNote);
this.openedList.Add(newPathNote);
continue;
}
}
this.openedList.Add(newPathNote); //创建节点(添加进开启列表)
}
this.colsedList.Add(pathNote); //把当前节点放进关闭列表
this.openedList.Remove(pathNote); //从开启列表移除当前节点
foreach (var openedNote in openedList)
{
if (openedNote.X == (int)endPoint.X && openedNote.Y == (int)endPoint.Y) // 到达终点
{
resultPoints = GetPointListByParent(openedNote, null); //得到以Point构成的路径
found = true;
break;
}
}
if (found)
{
break;
}
else
{
if (openedList.Count == 0) //找不到路径
{
break;
}
else
{
openedList.Sort(Compare);
pathNote = openedList[0];
}
}
}
return resultPoints;
}
/// <summary>
/// 比较两个节点的F值
/// </summary>
/// <param name="x">第一个节点</param>
/// <param name="y">第二个节点</param>
/// <returns></returns>
private int Compare(PathNote x, PathNote y)
{
if (x.F > y.F)
return 1;
else if (x.F < y.F)
return -1;
return 0;
}
/// <summary>
/// 组织传入的PathNote的所有父节点为List
/// </summary>
/// <param name="pathNote">PathNote</param>
/// <param name="pathPoints">列表</param>
/// <returns>路径</returns>
private List<Point> GetPointListByParent(PathNote pathNote, List<Point> pathPoints)
{
if (pathPoints == null)
pathPoints = new List<Point>();
if (pathNote.parentNote != null)
{
pathPoints.Add(new Point(pathNote.parentNote.X, pathNote.parentNote.Y));
GetPointListByParent(pathNote.parentNote, pathPoints);
}
return pathPoints;
}
/// <summary>
/// 开始寻找路径
/// </summary>
/// <returns></returns>
public List <Point> StartFindPath()
{
var found = false;
var pathNote = new PathNote()
{
F = 0, G = 0, H = 0, X = (int)startPoint.X, Y = (int)startPoint.Y, parentNote = null
};
List <Point> resultPoints = null;
while (true)
{
for (int i = 0; i < (diagonals ? 8 : 4); i++) //找到pathNote四方向或八方向周围节点,取F值最小的那个继续此过程
{
var x = pathNote.X + direction[i, 0];
var y = pathNote.Y + direction[i, 1];
if (x < 0 || y < 0 || x > matrix.GetUpperBound(0) || y > matrix.GetUpperBound(1)) //坐标过界
{
continue;
}
var newPathNote = new PathNote();
newPathNote.parentNote = pathNote;
newPathNote.X = x;
newPathNote.Y = y;
bool isClosed = false;
bool isOpened = false;
PathNote theOpendandSameNote = null;
foreach (var closedNote in colsedList)
{
if (closedNote.X == newPathNote.X && closedNote.Y == newPathNote.Y)
{
isClosed = true; //节点已经在关闭列表中
}
}
foreach (var openedNote in openedList)
{
if (openedNote.X == newPathNote.X && openedNote.Y == newPathNote.Y)
{
isOpened = true; //节点已经在开启列表中,稍后比较两条路径
theOpendandSameNote = openedNote;
}
}
if (matrix[newPathNote.X, newPathNote.Y] != 0 || isClosed) //不能通行或者已经在关闭列表中存在
{
continue;
}
if (Math.Abs(direction[i, 0] + direction[i, 1]) == 2) //G值
{
newPathNote.G = newPathNote.parentNote.G + 14;
}
else
{
newPathNote.G = newPathNote.parentNote.G + 10;
}
newPathNote.H = (int)(Math.Abs(endPoint.X - newPathNote.X) + Math.Abs(endPoint.Y - newPathNote.Y)) * 10; //H值
newPathNote.F = newPathNote.G + newPathNote.H; //F值
if (isOpened) //比较已在开启列表中的节点G值和准备创建的节点G值
{
if (newPathNote.G >= theOpendandSameNote.G)
{
this.openedList.Remove(pathNote);
continue;
}
else
{
this.openedList.Remove(theOpendandSameNote);
this.openedList.Add(newPathNote);
continue;
}
}
this.openedList.Add(newPathNote); //创建节点(添加进开启列表)
}
this.colsedList.Add(pathNote); //把当前节点放进关闭列表
this.openedList.Remove(pathNote); //从开启列表移除当前节点
foreach (var openedNote in openedList)
{
if (openedNote.X == (int)endPoint.X && openedNote.Y == (int)endPoint.Y) // 到达终点
{
resultPoints = GetPointListByParent(openedNote, null); //得到以Point构成的路径
found = true;
break;
}
}
if (found)
{
break;
}
else
{
if (openedList.Count == 0) //找不到路径
{
break;
}
else
{
openedList.Sort(Compare);
pathNote = openedList[0];
}
}
}
return(resultPoints);
}