/// <summary>
/// 计算路线
/// </summary>
/// <param name="preRoute">之前的路径，用于判断是否有死循环</param>
/// <param name="targetNum">目标位置</param>
/// <param name="maxStep">计算的最大次数</param>
/// <returns></returns>
private string GetRoute(string preRoute, string targetNum, ref int maxStep)//函数重载
{
int currStep = maxStep;
if (targetNum != TargetNum)//不相等表明TargetNum被重新赋值了，需要重新计算路径，应该就是有一个新的任务
{
//target changed, reset route
//Route为空说明不是所有方向都计算过了，需要继续计算
Route = "";
}
if (Route == NOROUTE)//route为“NOROUTE”表示经过计算没有可用路径，与route为空是两种情况，route为空是还未开始计算路径的状态
{
return NOROUTE;
}
//到达目的地
if (TargetNum == CellNum)
{
this.Route = ROUTESPLIT + CellNum + ROUTESPLIT;//cellnum表示计算路径中循环遍历过程的动态方块坐标
}
//如果路经不为空，说明之前已经计算出结果
if (Route != "")
{
//计算本次路径的长度
currStep = GetRouteStep(preRoute) + GetRouteStep(Route);
//如果本次路径长度为最小长度， 则限定其它路径的计算步数
if (currStep < maxStep)//maxstep为当前可用路径的计算步数
{
maxStep = currStep;
}
//返回路径
return Route;
}
string newRoute = NOROUTE;
//Route为空的情况
preRoute = preRoute + CellNum + ROUTESPLIT;
currStep = GetRouteStep(preRoute);
if (currStep >= maxStep)//表示现有路径长度大于已有路径的长度，此判断为确保选择最短路径
{
//路线长度超出范围
return NOROUTE;
}
Cell c;
Route route = new Route();
//计算向上的路径
if (UpRoute == "")
{
c = UpCell;
if (c != null)
{
//route.GetDirection(cmdId, c.CellNum);
//if (route.cell_yf == -1)
//{
if (preRoute.IndexOf(ROUTESPLIT + c.CellNum + ROUTESPLIT) == -1)
{
UpRoute = c.GetRoute(preRoute, targetNum, ref maxStep);
}
//}
}
else
{
UpRoute = NOROUTE;
}
}
//计算向下的路径
if (DownRoute == "")
{
c = DownCell;
if (c != null)
{
//route.GetDirection(cmdId, c.CellNum);
//if (route.cell_yb == -1)
//{
if (preRoute.IndexOf(ROUTESPLIT + c.CellNum + ROUTESPLIT) == -1)
{
DownRoute = c.GetRoute(preRoute, targetNum, ref maxStep);
}
//}
}
else
{
DownRoute = NOROUTE;
}
}
//计算向右的路径
if (RightRoute == "") //为空表示未计算
{
c = RightCell;
if (c != null)
{//查找c.CellNum在preRoute中出现的位置，返回-1表示没有找到，即preRoute中不包括c.CellNum，c.CellNum此处为rightcell的坐标位置，是为了保证不走回头路
//route.GetDirection(cmdId, c.CellNum);
//if (route.cell_xf == -1)
//{
if (preRoute.IndexOf(ROUTESPLIT + c.CellNum + ROUTESPLIT) == -1) //如果返回值大于0，说明历史路径已经包含本节点，需要排除，否则会有死循环
{
RightRoute = c.GetRoute(preRoute, targetNum, ref maxStep);
}
//}
}
else
{
//无右边节点，向右无法到达目的地
RightRoute = NOROUTE;
}
}
//计算向左的路径
if (LeftRoute == "")
{
c = LeftCell;
if (c != null)
{
//route.GetDirection(cmdId, c.CellNum);
//if (route.cell_xb == -1)
//{
if (preRoute.IndexOf(ROUTESPLIT + c.CellNum + ROUTESPLIT) == -1)
{
LeftRoute = c.GetRoute(preRoute, targetNum, ref maxStep);
}
//}
}
else
{
LeftRoute = NOROUTE;
}
}
//计算最短路径
string r = GetShortRoute(GetShortRoute(LeftRoute, RightRoute), GetShortRoute(UpRoute, DownRoute));
if (r == NOROUTE)
{
newRoute = r;//newRoute用来表示计算最终路径
}
else
{
newRoute = ROUTESPLIT + CellNum + r;
//计算当前路径的步数
currStep = currStep + GetRouteStep(newRoute);
if (currStep < maxStep)
{
maxStep = currStep;
}
}
if (LeftRoute != "" && RightRoute != "" && UpRoute != "" && DownRoute != "")
{
//四个方向都计算过了，保存路径，避免下次重复计算
this.Route = newRoute;
}
return newRoute;
}
/// <summary>
/// 定时器回调函数
/// </summary>
/// <param name="sender"></param>
void timer_Elapsed(object sender)
{
//if (tcp != null && tcp.Connected)
//{
// DataSet ds = GetTaskCmd();//获取发送命令
// string cmdId = "";
// int cnt = 0;
// byte[] buffer = null;
// for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
// {
// if (CanSendCmd((byte[])ds.Tables[0].Rows[i]["status"]))//判断小车状态是否能接收命令
// {
// buffer = (byte[])ds.Tables[0].Rows[i]["cmd"];
// workStream.Write(buffer, 0, buffer.Length);
// cmdId = Fn.ToString(ds.Tables[0].Rows[i]["cmd_id"]);
// cnt = Fn.ToInt(ds.Tables[0].Rows[i]["send_cnt"]) + 1;
// UpdateCmdSendCnt(cmdId, cnt); //更新命令的发送次数
// }
// }
// //发送路权令牌
// DataSet dsToken = GetRoadRightCMD();
// byte[] bufferRight = null;
// for (int j = 0; j < dsToken.Tables[0].Rows.Count; j++)
// {
// bufferRight = Asrv.GetSendData(Asrv.GetTokenCmd(Fn.ToInt(dsToken.Tables[0].Rows[j]["step"])), (byte[])(dsToken.Tables[0].Rows[j]["address"]));
// cmdId = Fn.ToString(dsToken.Tables[0].Rows[j]["cmd_id"]);
// if (CheckTokenSendCnt(cmdId, bufferRight)) //如果相同的令牌发送次数没有超过最大发送次数则发送路权令牌
// {
// workStream.Write(bufferRight, 0, bufferRight.Length);
// InsertCmdBreakdown(cmdId, bufferRight);
// }
// }
//}
//else
//{
// Connect();//连接HOST并等待接收数据
//}
string cmdId = GetCmdId();
//如果没有未分配的任务，只计算路权
if (cmdId == "0")
{
SetRoadRight();
UpdateCmd();
return;
}
Route r = new Route();
r.CalcRoute(cmdId);
SetRoadRight();
UpdateCmd();
}