//在网格上设置点的信息
private void InitPoint()
{
for (int i = 0; i < mGridWidth; i++)
{
for (int j = 0; j < mGridHeight; j++)
{
mPointGrid[i, j] = new AStarPoint(i, j);
}
}
//设置障碍物
mPointGrid[4, 2].isObstacle = true;
mPointGrid[4, 3].isObstacle = true;
mPointGrid[4, 4].isObstacle = true;
mPointGrid[4, 5].isObstacle = true;
mPointGrid[4, 6].isObstacle = true;
//显示障碍物
for (int x = 0; x < mGridWidth; x++)
{
for (int y = 0; y < mGridHeight; y++)
{
if (mPointGrid[x, y].isObstacle)
{
CreatePath(x, y, Color.blue);
}
}
}
}
private List <AStarPoint> ShowPath(AStarPoint start, AStarPoint end)
{
mPathPosList.Clear();
AStarPoint temp = end;
while (true)
{
mPathPosList.Add(temp);
Color c = Color.white;
if (temp == start)
{
c = Color.green;
}
else if (temp == end)
{
c = Color.red;
}
CreatePath(temp.pointPositionX, temp.pointPositionY, c);
if (temp.parentPoint == null)
{
break;
}
temp = temp.parentPoint;
}
return(mPathPosList);
}
private void Start()
{
mCubeParent = GameObject.Find("Plane");
mPointGrid = AStarAlgorithm.Ins.mPointGrid;
mStartPos = mPointGrid[0, 0];
InitBG();
}
//寻路
public List <AStarPoint> FindPath(AStarPoint mStartPoint, AStarPoint mEndPoint)
{
if (mEndPoint.isObstacle || mStartPoint.pointPosition == mEndPoint.pointPosition)
{
return(null);
}
//开启列表
List <AStarPoint> openPointList = new List <AStarPoint>();
//关闭列表
List <AStarPoint> closePointList = new List <AStarPoint>();
openPointList.Add(mStartPoint);
while (openPointList.Count > 0)
{
//寻找开启列表中最小预算值的表格
AStarPoint minFPoint = FindPointWithMinF(openPointList);
//将当前表格从开启列表移除 在关闭列表添加
openPointList.Remove(minFPoint);
closePointList.Add(minFPoint);
//找到当前点周围的全部点
List <AStarPoint> surroundPoints = FindSurroundPoint(minFPoint);
//在周围的点中，将关闭列表里的点移除掉
SurroundPointsFilter(surroundPoints, closePointList);
//寻路逻辑
foreach (var surroundPoint in surroundPoints)
{
if (openPointList.Contains(surroundPoint))
{
//计算下新路径下的G值（H值不变的，比较G相当于比较F值）
float newPathG = CalcG(surroundPoint, minFPoint);
if (newPathG < surroundPoint.aStarG)
{
surroundPoint.aStarG = newPathG;
surroundPoint.aStarF = surroundPoint.aStarG + surroundPoint.aStarH;
surroundPoint.parentPoint = minFPoint;
}
}
else
{
//将点之间的
surroundPoint.parentPoint = minFPoint;
CalcF(surroundPoint, mEndPoint);
openPointList.Add(surroundPoint);
}
}
//如果开始列表中包含了终点，说明找到路径
if (openPointList.IndexOf(mEndPoint) > -1)
{
break;
}
}
return(ShowPath(mStartPoint, mEndPoint));
}
private void Walk()
{
if (mPathPosList != null && mPathPosList.Count > 1)
{
mStartPos = mPathPosList[mPathPosList.Count - 1];
Color color = mStartPos.aStarObject.GetComponent <Renderer>().material.color;
mPathPosList.Remove(mStartPos);
Destroy(mStartPos.aStarObject);
mStartPos.aStarObject = null;
mStartPos = mPathPosList[mPathPosList.Count - 1];
mStartPos.aStarObject.GetComponent <Renderer>().material.color = color;
}
}
public void FindPath(int mTargetX, int mTargetY)
{
if (mPathPosList != null)
{
mPathPosList.Clear();
}
AStarAlgorithm.Ins.ClearGrid();
//网格点对象重新刷新了 需要使用网格来索引到点 mPathPosList存储的点是之前的AStarPoint
this.mEndPos = mPointGrid[mTargetX, mTargetY];
this.mStartPos = mPointGrid[mStartPos.pointPositionX, mStartPos.pointPositionY];
mPathPosList = AStarAlgorithm.Ins.FindPath(this.mStartPos, mEndPos);
}
//寻找预计值最小的格子
private AStarPoint FindPointWithMinF(List <AStarPoint> openPointList)
{
float f = float.MaxValue;
AStarPoint temp = null;
foreach (AStarPoint p in openPointList)
{
if (p.aStarF < f)
{
temp = p;
f = p.aStarF;
}
}
return(temp);
}
//计算该点到终点的F值
private void CalcF(AStarPoint now, AStarPoint end)
{
//F = G + H
float h = Mathf.Abs(end.pointPositionX - now.pointPositionX) + Mathf.Abs(end.pointPositionY - now.pointPositionY);
float g = 0;
if (now.parentPoint == null)
{
g = 0;
}
else
{
g = Vector2.Distance(new Vector2(now.pointPositionX, now.pointPositionY), new Vector2(now.parentPoint.pointPositionX, now.parentPoint.pointPositionY)) + now.parentPoint.aStarG;
}
float f = g + h;
now.aStarF = f;
now.aStarG = g;
now.aStarH = h;
}
//计算最小预算值点G值
private float CalcG(AStarPoint surround, AStarPoint minFPoint)
{
return(Vector3.Distance(surround.pointPosition, minFPoint.pointPosition) + minFPoint.aStarG);
}
//寻找周围的全部点
private List <AStarPoint> FindSurroundPoint(AStarPoint point)
{
List <AStarPoint> list = new List <AStarPoint>();
////////////判断周围的八个点是否在网格内/////////////
AStarPoint up = null, down = null, left = null, right = null;
AStarPoint lu = null, ru = null, ld = null, rd = null;
if (point.pointPositionY < mGridHeight - 1)
{
up = mPointGrid[point.pointPositionX, point.pointPositionY + 1];
}
if (point.pointPositionY > 0)
{
down = mPointGrid[point.pointPositionX, point.pointPositionY - 1];
}
if (point.pointPositionX > 0)
{
left = mPointGrid[point.pointPositionX - 1, point.pointPositionY];
}
if (point.pointPositionX < mGridWidth - 1)
{
right = mPointGrid[point.pointPositionX + 1, point.pointPositionY];
}
if (up != null && left != null)
{
lu = mPointGrid[point.pointPositionX - 1, point.pointPositionY + 1];
}
if (up != null && right != null)
{
ru = mPointGrid[point.pointPositionX + 1, point.pointPositionY + 1];
}
if (down != null && left != null)
{
ld = mPointGrid[point.pointPositionX - 1, point.pointPositionY - 1];
}
if (down != null && right != null)
{
rd = mPointGrid[point.pointPositionX + 1, point.pointPositionY - 1];
}
/////////////将可以经过的表格添加到开启列表中/////////////
if (down != null && down.isObstacle == false)
{
list.Add(down);
}
if (up != null && up.isObstacle == false)
{
list.Add(up);
}
if (left != null && left.isObstacle == false)
{
list.Add(left);
}
if (right != null && right.isObstacle == false)
{
list.Add(right);
}
if (lu != null && lu.isObstacle == false && left.isObstacle == false && up.isObstacle == false)
{
list.Add(lu);
}
if (ld != null && ld.isObstacle == false && left.isObstacle == false && down.isObstacle == false)
{
list.Add(ld);
}
if (ru != null && ru.isObstacle == false && right.isObstacle == false && up.isObstacle == false)
{
list.Add(ru);
}
if (rd != null && rd.isObstacle == false && right.isObstacle == false && down.isObstacle == false)
{
list.Add(rd);
}
return(list);
}
