/// <summary>
/// 对角线估价法
/// </summary>
/// <param name="startAStarNodeData"></param>
/// <param name="endAStarNodeData"></param>
/// <param name="diagCost"></param>
/// <param name="straightCost"></param>
/// <returns></returns>
public int Diagonal(AStarNodeData startAStarNodeData, AStarNodeData endAStarNodeData, int diagCost = 14, int straightCost = 10)
{
int dx = Mathf.Abs(startAStarNodeData.x - endAStarNodeData.x);
int dy = Mathf.Abs(startAStarNodeData.y - endAStarNodeData.y);
int diag = Mathf.Min(dx, dy);
int straight = dx + dy;
return(diagCost * diag + straightCost * (straight - 2 * diag));
}
public List <AStarNodeData> AStarFindPath(Vector3 start, Vector3 end)
{
AStarNodeData startAStarNodeData = GetAStarNodeData(start);
AStarNodeData endAStarNodeData = GetAStarNodeData(end);
List <AStarNodeData> openList = new List <AStarNodeData>(); //等待检查列表
HashSet <AStarNodeData> closeList = new HashSet <AStarNodeData>(); //检查完成列表
openList.Add(startAStarNodeData);
while (openList.Count > 0)
{
AStarNodeData current = openList[0];
for (int i = 0; i < openList.Count; i++)
{
//等待检查列表里最短距离的节点
if (openList[i].FCost <= current.FCost && openList[i].hCost < current.hCost)
{
current = openList[i];
}
}
openList.Remove(current);
closeList.Add(current);
if (current == endAStarNodeData)
{
return(GeneratePath(startAStarNodeData, endAStarNodeData));
}
foreach (AStarNodeData item in GetAStarNodeDataAround(current))
{
if (item.isWall || closeList.Contains(item))
{
continue;
}
//计算与开始节点的距离
int gCost = current.gCost + GetAStarNodeDataDistance(current, item);
//如果不在等待检查列表中或者与开始节点的距离更小
if (!openList.Contains(item) || gCost < item.gCost)
{
//更新与开始节点的距离
item.gCost = gCost;
//更新与end节点的距离
item.hCost = GetAStarNodeDataDistance(item, endAStarNodeData);
//更新父节点为当前选定的节点
//在考查从一个节点移动到另一个节点时,总是拿自身节点周围的8个相邻节点来说事儿,相对于周边的节点来讲,自身节点称为它们的父节点.
item.parent = current;
if (!openList.Contains(item))
{
openList.Add(item);
}
}
}
}
return(GeneratePath(startAStarNodeData, null));
}
/// <summary>
/// 取得周围的节点
/// </summary>
/// <param name="data"></param>
/// <returns></returns>
public List <AStarNodeData> GetAStarNodeDataAround(AStarNodeData data)
{
List <AStarNodeData> dataList = new List <AStarNodeData>();
for (int i = -1; i <= 1; i++)
{
for (int j = -1; j <= 1; j++)
{
//自己
if (i == 0 && j == 0)
{
continue;
}
int x = data.x + i;
int y = data.y + j;
if (x < 0)
{
x = w - x;
if (!(x < w * 2 && x > w))
{
continue;
}
}
else
{
if (!(x <= w && x >= 0))
{
continue;
}
}
if (y < 0)
{
y = h - y;
if (!(y < h * 2 && y > h))
{
continue;
}
}
else
{
if (!(y <= h && y >= 0))
{
continue;
}
}
dataList.Add(aStarNodeDatas[x, y]);
}
}
return(dataList);
}
/// <summary>
/// 生成路径
/// </summary>
/// <param name="startAStarNodeData"></param>
/// <param name="endAStarNodeData"></param>
/// <returns></returns>
public List <AStarNodeData> GeneratePath(AStarNodeData startAStarNodeData, AStarNodeData endAStarNodeData)
{
List <AStarNodeData> pathList = new List <AStarNodeData>();
if (endAStarNodeData != null)
{
AStarNodeData temp = endAStarNodeData;
while (temp != startAStarNodeData)
{
pathList.Add(temp);
temp = temp.parent;
}
pathList.Reverse();
}
UpdatePath(pathList.ToArray());
return(pathList);
}
/// <summary>
/// 获取两个节点之间的距离
/// </summary>
/// <param name="startAStarNodeData"></param>
/// <param name="endAStarNodeData"></param>
/// <returns></returns>
public int GetAStarNodeDataDistance(AStarNodeData startAStarNodeData, AStarNodeData endAStarNodeData)
{
return(Diagonal(startAStarNodeData, endAStarNodeData));
}
public void InitManager(float radius, LayerMask layer, bool isShowWall, bool isShowPath, GameObject gameObject, float ratio = 1)
{
this.radius = radius;
this.layer = layer;
this.isShowWall = isShowWall;
this.isShowPath = isShowPath;
w = Mathf.RoundToInt(gameObject.GetComponent <BoxCollider2D>().bounds.size.x *ratio);
h = Mathf.RoundToInt(gameObject.GetComponent <BoxCollider2D>().bounds.size.y *ratio);
aStarNodeDatas = new AStarNodeData[w * 2, h * 2];
wall = new GameObject("Wall").transform;
path = new GameObject("Path").transform;
//将墙的信息写入格子中
for (int x = 0; x <= w; x++)
{
for (int y = 0; y <= h; y++)
{
Vector3 localPosition = new Vector3(x * 0.5f, y * 0.5f, 0);
//通过节点中心发射圆形射线,检测当前位置是否可以行走
bool wall = false;
//wall = Physics.CheckSphere(localPosition, radius, layer); 3D
Collider2D[] colliders = Physics2D.OverlapCircleAll(localPosition, radius, layer);
if (colliders.Length > 0)
{
wall = true;
}
aStarNodeDatas[x, y] = new AStarNodeData(wall, localPosition, x, y);
if (wall)
{
//InitWallGrid(localPosition, isShowWall);
}
}
}
for (int x = -w + 1; x < 0; x++)
{
for (int y = 0; y <= h; y++)
{
Vector3 localPosition = new Vector3(x * 0.5f, y * 0.5f, 0);
bool wall = false;
Collider2D[] colliders = Physics2D.OverlapCircleAll(localPosition, radius, layer);
if (colliders.Length > 0)
{
wall = true;
}
aStarNodeDatas[w - x, y] = new AStarNodeData(wall, localPosition, x, y);
if (wall)
{
//InitWallGrid(localPosition, isShowWall);
}
}
}
for (int x = 0; x <= w; x++)
{
for (int y = -h + 1; y < 0; y++)
{
Vector3 localPosition = new Vector3(x * 0.5f, y * 0.5f, 0);
bool wall = false;
Collider2D[] colliders = Physics2D.OverlapCircleAll(localPosition, radius, layer);
if (colliders.Length > 0)
{
wall = true;
}
aStarNodeDatas[x, h - y] = new AStarNodeData(wall, localPosition, x, y);
if (wall)
{
//InitWallGrid(localPosition, isShowWall);
}
}
}
for (int x = -w + 1; x < 0; x++)
{
for (int y = -h + 1; y < 0; y++)
{
Vector3 localPosition = new Vector3(x * 0.5f, y * 0.5f, 0);
bool wall = false;
Collider2D[] colliders = Physics2D.OverlapCircleAll(localPosition, radius, layer);
if (colliders.Length > 0)
{
wall = true;
}
aStarNodeDatas[w - x, h - y] = new AStarNodeData(wall, localPosition, x, y);
if (wall)
{
//InitWallGrid(localPosition, isShowWall);
}
}
}
}