char *
benum(c)
{
dest_no = c -= '0';
switch (dest_type) {
case T_BEACON:
if (c >= sp->num_beacons)
return ("Unknown beacon");
p.new_dir = DIR_FROM_DXDY(sp->beacon[c].x - p.xpos,
sp->beacon[c].y - p.ypos);
break;
case T_EXIT:
if (c >= sp->num_exits)
return ("Unknown exit");
p.new_dir = DIR_FROM_DXDY(sp->exit[c].x - p.xpos,
sp->exit[c].y - p.ypos);
break;
case T_AIRPORT:
if (c >= sp->num_airports)
return ("Unknown airport");
p.new_dir = DIR_FROM_DXDY(sp->airport[c].x - p.xpos,
sp->airport[c].y - p.ypos);
break;
default:
return ("Unknown case in benum! Get help!");
break;
}
return (NULL);
}
const char *
delayb(char c)
{
int xdiff, ydiff;
c -= '0';
if (c >= sp->num_beacons)
return ("Unknown beacon");
xdiff = sp->beacon[(int)c].x - p.xpos;
xdiff = SGN(xdiff);
ydiff = sp->beacon[(int)c].y - p.ypos;
ydiff = SGN(ydiff);
if (xdiff != displacement[p.dir].dx || ydiff != displacement[p.dir].dy)
return ("Beacon is not in flight path");
if (xdiff != 0 && ydiff !=0)
if (abs(sp->beacon[(int)c].x - p.xpos) !=
abs(sp->beacon[(int)c].y - p.ypos))
return ("Beacon is not in flight path");
p.delayd = 1;
p.delayd_no = c;
if (dest_type != T_NODEST) {
switch (dest_type) {
case T_BEACON:
xdiff = sp->beacon[dest_no].x - sp->beacon[(int)c].x;
ydiff = sp->beacon[dest_no].y - sp->beacon[(int)c].y;
break;
case T_EXIT:
xdiff = sp->exit[dest_no].x - sp->beacon[(int)c].x;
ydiff = sp->exit[dest_no].y - sp->beacon[(int)c].y;
break;
case T_AIRPORT:
xdiff = sp->airport[dest_no].x - sp->beacon[(int)c].x;
ydiff = sp->airport[dest_no].y - sp->beacon[(int)c].y;
break;
default:
return ("Bad case in delayb! Get help!");
break;
}
if (xdiff == 0 && ydiff == 0)
return ("Would already be there");
p.new_dir = DIR_FROM_DXDY(xdiff, ydiff);
if (p.new_dir == p.dir)
return ("Already going in that direction");
}
return (NULL);
}
