MAXMOT
if (dx[i] > MAXMOT)
dx[i] = MAXMOT;
else if (dx[i] < -MAXMOT)
dx[i] = -MAXMOT;
if (dy[i] > MAXMOT)
dy[i] = MAXMOT;
else if (dy[i] < -MAXMOT)
dy[i] = -MAXMOT;