int data1[2], data2[2], DBTM = 2, ODBTM = 2;
  float pos1x, pos1y, pos2x, pos2y, dsq;
  double hvx = 0, hvy = 0, direction = 2*M_PI; //direction is the angle of the craft's orientation compared to the x axis, in radians! (going anticlockwise from the east) eg, 2pi = forward, pi/2 = facing to the left, pi = facing backwards, 3pi/2 = facing right, 0 = 2pi. direction = direction +- 2pi. in math.h pi is defined as M_PI. pi/2 = M_PI_2
  data1[1]=0;
  data1[2]=0;
  data2[1]=-1;
  data2[2]=1;
  pos1x = data1[1];
  pos1y = data1[2];
  while (((pow(DBTM+sqrt(data2[1]*data2[1]+data2[2]*data2[2]),2)-dsq)*(dsq-pow(DBTM-sqrt(data2[1]*data2[1]+data2[2]*data2[2]),2))>0) && (DBTM >= 0))
  {
        dsq = pow(DBTM-data1[1],2) + (data1[2]*data1[2]);
        DBTM--;
  }
  if (DBTM < 1) {DBTM = ODBTM;}
  while (((pow(DBTM+sqrt(data2[1]*data2[1]+data2[2]*data2[2]),2)-dsq)*(dsq-pow(DBTM-sqrt(data2[1]*data2[1]+data2[2]*data2[2]),2))>0) && (DBTM < (ODBTM * 2.0)))
  {
        dsq = pow(DBTM-data1[1],2) + (data1[2]*data1[2]);
        DBTM++;
  }
  if (DBTM<ODBTM*2.0)
  {
    dsq = pow(DBTM-data1[1],2) + (data1[2]*data1[2]);
    pos2x = DBTM;
    pos2y = 0;
    if (data2[2]<=0)
    {
     pos2y = (0.5 * (0 + data1[2])) + (0.5 * (0 - data1[2]) * (pow(DBTM,2) - (data2[1]*data2[1]+data2[2]*data2[2])) / dsq) - (2.0 * (DBTM-data1[1])*(0.25*sqrt(((pow(DBTM+sqrt(data2[1]*data2[1]+data2[2]*data2[2]),2)-dsq)*(dsq-pow(DBTM-sqrt(data2[1]*data2[1]+data2[2]*data2[2]),2)))))/dsq);
    }
    else if (data2[2]>0)
    {
     pos2y = (0.5 * (0 + data1[2])) + (0.5 * (0 - data1[2]) * (pow(DBTM,2) - (data2[1]*data2[1]+data2[2]*data2[2])) / dsq) + (2.0 * (DBTM-data1[1])*(0.25*sqrt(((pow(DBTM+sqrt(data2[1]*data2[1]+data2[2]*data2[2]),2)-dsq)*(dsq-pow(DBTM-sqrt(data2[1]*data2[1]+data2[2]*data2[2]),2)))))/dsq);
    }
    if (data2[1]<=0)
    {
     pos2x = (0.5 * (DBTM + data1[1])) + (0.5 * (DBTM - data1[1]) * (pow(DBTM,2) - (data2[1]*data2[1]+data2[2]*data2[2])) / dsq) - (2.0 * (0-data1[2])*(0.25*sqrt(((pow(DBTM+sqrt(data2[1]*data2[1]+data2[2]*data2[2]),2)-dsq)*(dsq-pow(DBTM-sqrt(data2[1]*data2[1]+data2[2]*data2[2]),2)))))/dsq);
    }
    else if (data2[1]>0)
    {
     pos2x = (0.5 * (DBTM + data1[1])) + (0.5 * (DBTM - data1[1]) * (pow(DBTM,2) - (data2[1]*data2[1]+data2[2]*data2[2])) / dsq) + (2.0 * (0-data1[2])*(0.25*sqrt(((pow(DBTM+sqrt(data2[1]*data2[1]+data2[2]*data2[2]),2)-dsq)*(dsq-pow(DBTM-sqrt(data2[1]*data2[1]+data2[2]*data2[2]),2)))))/dsq);
    }
  } else {
  DBTM = ODBTM;
  pos2x = DBTM+data2[1];
  pos2y = data2[2];
  }

  if ((pos2x-pos1x > pow (2, -24)) || (pos2y-pos2x > pow (2, -24)) || (pos2y-pos2x < -pow (2, -24)) || (pos2y-pos2x < -pow (2, -24))) //pow(2, -24) = machine epsilon of "float"
  {
   direction += atan2(pos2y-pos1y, pos2x-pos1x);
   if (direction <= pow (2, -24)) {direction+=2*M_PI;}
   if (direction > 2*M_PI) {direction-=2*M_PI;}
  }

  printf("pos1x: %.1f\npos1y: %.1f\npos2x: %.1f\npos2y: %.1f\ndirection: %.5f\n",pos1x,pos1y,pos2x,pos2y,direction);