protected void AddNodeToOpenList(AStarNode node)
{
node.astarInListType = AStarNodeInListType.Open_List;
openHeap.Push(node);
handledDict[node.pos] = node;
}
/// <summary>
/// 构建路径
/// </summary>
/// <param name="startCell"></param>
/// <param name="startPos"></param>
/// <param name="endCell"></param>
/// <param name="endPos"></param>
/// <returns></returns>
public List <Vector2> BuildPath(Cell startCell, Vector2 startPos,
Cell endCell, Vector2 endPos)
{
openList.Clear();
closedList.Clear();
endCell.g = 0;
endCell.ComputeH(endPos, startPos);
endCell.ComputeF();
endCell.isOpen = false;
endCell.parent = null;
endCell.sessionId = pathSessionId;
openList.Push(endCell);
bool isFoundPath = false; //是否找到路径
Cell currNode; //当前节点
Cell adjacentTmp = null; //当前节点的邻接三角型
while (openList.Size > 0)
{
// 1. 把当前节点从开放列表删除, 加入到封闭列表
currNode = openList.Pop();
closedList.Add(currNode);
//路径是在同一个三角形内
if (currNode == startCell)
{
isFoundPath = true;
break;
}
// 2. 对当前节点相邻的每一个节点依次执行以下步骤:
//所有邻接三角型
int adjacentId;
for (int i = 0; i < 3; i++)
{
adjacentId = currNode.linkList[i];
// 3. 如果该相邻节点不可通行或者该相邻节点已经在封闭列表中,
// 则什么操作也不执行,继续检验下一个节点;
if (adjacentId < 0) //不能通过
{
continue;
}
adjacentTmp = cellList[adjacentId];
if (adjacentTmp != null)
{
if (adjacentTmp.sessionId != pathSessionId)
{
// 4. 如果该相邻节点不在开放列表中,则将该节点添加到开放列表中,
// 并将该相邻节点的父节点设为当前节点,同时保存该相邻节点的G和F值;
adjacentTmp.sessionId = pathSessionId;
adjacentTmp.parent = currNode;
adjacentTmp.isOpen = true;
// remember the side this caller is entering from
adjacentTmp.SetAndGetArrivalWall(currNode.index);
//计算G值
//当前的g值+（当前边的进入边的中点-当前边出边的中点）的距离
var p1 = Equals(currNode, endCell)
? endPos
: currNode.lineList[currNode.arrivalWall].center;
adjacentTmp.g =
currNode.g + adjacentTmp.ComputeGIncrease(p1, currNode.lineList[i].center);
//计算H值
adjacentTmp.ComputeH(adjacentTmp.lineList[adjacentTmp.arrivalWall].center, startPos);
//计算F值
adjacentTmp.ComputeF();
//放入开放列表并排序
openList.Push(adjacentTmp);
}
else
{
// 5. 如果该相邻节点在开放列表中,
// 则判断若经由当前节点到达该相邻节点的G值是否小于原来保存的G值,
// 若小于,则将该相邻节点的父节点设为当前节点,并重新设置该相邻节点的G和F值
if (adjacentTmp.isOpen) //已经在openList中
{
//计算G值
//当前的g值+（当前边的进入边的中点-当前边出边的中点）的距离
var p1 = Equals(currNode, endCell)
? endPos
: currNode.lineList[currNode.arrivalWall].center;
float increaseG = adjacentTmp.ComputeGIncrease(p1, currNode.lineList[i].center);
if (currNode.g + increaseG < adjacentTmp.g)
{
adjacentTmp.g = currNode.g;
adjacentTmp.parent = currNode;
// remember the side this caller is entering from
adjacentTmp.SetAndGetArrivalWall(currNode.index);
//重新设置在heap中的位置
openList.Remove(adjacentTmp);
openList.Push(adjacentTmp);
}
}
else //已在closeList中
{
adjacentTmp = null;
continue;
}
}
}
}
}
//由网格路径生成路径
return(isFoundPath ? GetPath(startPos, endPos) : null);
/*返回cell
* List<Vector2> ret = new List<Vector2>();
* foreach (Cell cell in GetCellPath())
* {
* ret.Add(cell.Center);
* }
* return ret;
* */
}
