void guidanceSimulation()
    {
        vt1 = (-vt) * Math.Cos(beta);
        vt2 = vt * Math.Sin(beta*Math.PI/180);
        he = hedeg / 57.3;
        rtm1 = rt1 - rm1;
        rtm2 = rt2 - rm2;
        rtm = Math.Sqrt(rtm1 * rtm1 + rtm2 * rtm2);
        xlam = Math.Atan2(rtm2, rtm1);
        xlead = Math.Asin((vt * Math.Sin(beta*Math.PI/180 + xlam * Math.PI / 180)) / vm);
        thet = xlam + xlead;
        vm1 = vm * Math.Cos(thet * Math.PI / 180 + he * Math.PI / 180);
        vm2 = vm * Math.Sin(thet * Math.PI / 180 + he * Math.PI / 180);
        vtm1 = vt1 - vm1;
        vtm2 = vt2 - vm2;
        vc = -(rtm1 * vtm1 + rtm2 * vtm2) / rtm;
        xnc = xnp * vc * xlam;
        am1 = (-xnc) * Math.Sin(xlam * Math.PI / 180);
        am2 = (xnc) * Math.Cos(xlam * Math.PI / 180);
        betad = (xnt) / vt;
        beta += Time.deltaTime * betad;
        vm1 += Time.deltaTime * am1;
        vm2 += Time.deltaTime * am2;
        rm1 += Time.deltaTime * vm1;
        rm2 += Time.deltaTime * vm2;
        #region
        //while (vc >= 0)
        //{
        //    if (rtm < 1000)
        //        h = 0.0002;
        //    else
        //        h = 0.01;

        //    betaold = beta;
        //    rt1old = rt1;
        //    rt2old = rt2;
        //    rm1old = rm1;
        //    rm2old = rm2;
        //    vm1old = vm1;
        //    vm2old = vm2;
        //    int step = 1;
        //    int flag = 0;
        //    while(step <= 1)
        //    {
        //        if(flag == 1)
        //        {
        //            step = 2;
        //            beta = beta + h * betad;
        //            rt1 = rt1 + h * vt1;
        //            rt2 = rt2 + h * vt2;
        //            rm1 = rm1 + h * vm1;
        //            rm2 = rm2 + h * vm2;
        //            vm1 = vm1 + h * am1;
        //            vm2 = vm2 + h * am2;
        //            t = t + h;
        //        }
        //        rtm1 = rt1 - rm1;
        //        rtm2 = rt2 - rm2;
        //        rtm = Math.Sqrt(rtm1 * rtm1 + rtm2 * rtm2);
        //        vtm1 = vt1 - vm1;
        //        vtm2 = vt2 - vm2;
        //        vc = -(rtm1 * vtm1 + rtm2 * vtm2) / rtm;
        //        xlam = Math.Atan2(rtm2, rtm1);
        //        xlamd = (rtm1 * vtm2 - rtm2 * vtm1) / (rtm * rtm);

        //        //double XNC1 = ( (xnp + 20000000 * xlamd  * xlamd) / vc) * vc * xlamd;
        //        am1 = -xnc * Math.Sin(xlam);
        //        am2 = xnc * Math.Cos(xlam);
        //        vt1 = -vt * Math.Cos(beta);
        //        vt2 = vt * Math.Sin(beta);
        //        betad = xnt / vt;
        //        flag = 1;
        //    }
        //    flag = 0;
        //    beta = .5 * (betaold + beta + h * betad);
        //    rt1 = .5 * (rt1old + rt1 + h * vt1);
        //    rt2 = .5 * (rt2old + rt2 + h * vt2);
        //    rm1 = .5 * (rm1old + rm1 + h * vm1);
        //    rm2 = .5 * (rm2old + rm2 + h * vm2);
        //    vm1 = .5 * (vm1old + vm1 + h * am1);
        //    vm2 = .5 * (vm2old + vm2 + h * am2);
        //    s = s + h;
        //    if (s >= 0.09999)
        //        s = 0;
        //}
        #endregion
    }