Example #1
0
void
TacticalAI::SelectTargetOpportunity()
{
    // NON-COMBATANTS do not pick targets of opportunity:
    if (ship->GetIFF() == 0)
    return;

    SimObject* potential_target = 0;

    // pick the closest combatant ship with a different IFF code:
    double target_dist = ship->Design()->commit_range;

    SimObject* ward   = ship_ai->GetWard();

    // FRIGATES are primarily anti-air platforms, but may
    // also attack smaller starships:

    if (ship->Class() == Ship::CORVETTE || ship->Class() == Ship::FRIGATE) {
        Ship* current_ship_target = 0;
        Shot* current_shot_target = 0;

        // if we are escorting a larger warship, it is good to attack
        // the same target as our ward:

        if (ward) {
            Ship* s = (Ship*) ward;

            if (s->Class() > ship->Class()) {
                SimObject* obj = s->GetTarget();

                if (obj && obj->Type() == SimObject::SIM_SHIP) {
                    current_ship_target = (Ship*) obj;
                    target_dist = (ship->Location() - obj->Location()).length();
                }
            }
        }

        ListIter<Contact> contact = ship->ContactList();
        while (++contact) {
            Ship* c_ship = contact->GetShip();
            Shot* c_shot = contact->GetShot();

            if (!c_ship && !c_shot)
            continue;

            int   c_iff  = contact->GetIFF(ship);
            bool  rogue  = c_ship && c_ship->IsRogue();
            bool  tgt_ok = c_iff > 0               &&
            c_iff != ship->GetIFF() &&
            c_iff < 1000;

            if (rogue || tgt_ok) {
                if (c_ship && c_ship != ship && !c_ship->InTransition()) {
                    if (c_ship->Class() <  Ship::DESTROYER || 
                            (c_ship->Class() >= Ship::MINE && c_ship->Class() <= Ship::DEFSAT)) {
                        // found an enemy, check distance:
                        double dist = (ship->Location() - c_ship->Location()).length();

                        if (dist < 0.75 * target_dist &&
                                (!current_ship_target || c_ship->Class() <= current_ship_target->Class())) {
                            current_ship_target = c_ship;
                            target_dist = dist;
                        }
                    }
                }

                else if (c_shot) {
                    // found an enemy shot, is there enough time to engage?
                    if (c_shot->GetEta() < 3)
                    continue;

                    // found an enemy shot, check distance:
                    double dist = (ship->Location() - c_shot->Location()).length();

                    if (!current_shot_target) {
                        current_shot_target = c_shot;
                        target_dist = dist;
                    }

                    // is this shot a better target than the one we've found?
                    else {
                        Ship* ward = ship_ai->GetWard();

                        if ((c_shot->IsTracking(ward) || c_shot->IsTracking(ship)) &&
                                (!current_shot_target->IsTracking(ward) || 
                                    !current_shot_target->IsTracking(ship))) {
                            current_shot_target = c_shot;
                            target_dist = dist;
                        }
                        else if (dist < target_dist) {
                            current_shot_target = c_shot;
                            target_dist = dist;
                        }
                    }
                }
            }
        }

        if (current_shot_target)
        potential_target = current_shot_target;
        else
        potential_target = current_ship_target;
    }

    // ALL OTHER SHIP CLASSES ignore fighters and only engage
    // other starships:

    else {
        List<Ship> ward_threats;

        ListIter<Contact> contact = ship->ContactList();
        while (++contact) {
            Ship* c_ship = contact->GetShip();

            if (!c_ship)
            continue;

            int   c_iff  = contact->GetIFF(ship);
            bool  rogue  = c_ship->IsRogue();
            bool  tgt_ok = c_ship != ship          && 
            c_iff > 0               && 
            c_iff != ship->GetIFF() && 
            !c_ship->InTransition();

            if (rogue || tgt_ok) {
                if (c_ship->IsStarship() || c_ship->IsStatic()) {
                    // found an enemy, check distance:
                    double dist = (ship->Location() - c_ship->Location()).length();

                    if (dist < 0.75 * target_dist) {
                        potential_target = c_ship;
                        target_dist = dist;
                    }

                    if (ward && c_ship->IsTracking(ward)) {
                        ward_threats.append(c_ship);
                    }
                }
            }
        }

        // if this ship is protecting a ward,
        // prefer targets that are threatening that ward:
        if (potential_target && ward_threats.size() && !ward_threats.contains((Ship*)potential_target)) {
            target_dist *= 2;
            
            ListIter<Ship> iter = ward_threats;
            while (++iter) {
                Ship* threat = iter.value();

                double dist = (ward->Location() - threat->Location()).length();

                if (dist < target_dist) {
                    potential_target = threat;
                    target_dist = dist;
                }
            }
        }
    }

    if (ship->Class() != Ship::CARRIER && ship->Class() != Ship::SWACS)
    ship_ai->SetTarget(potential_target);
}
Example #2
0
void
TacticalAI::SelectTarget()
{
    if (!ship) {
        roe = NONE;
        return;
    }

    // unarmed vessels should never engage an enemy:
    if (ship->Weapons().size() < 1)
    roe = NONE;

    SimObject* target = ship_ai->GetTarget();
    SimObject* ward   = ship_ai->GetWard();

    // if not allowed to engage, drop and return:
    if (roe == NONE) {
        if (target)
        ship_ai->DropTarget();
        return;
    }

    // if we have abandoned our ward, drop and return:
    if (ward && roe != AGRESSIVE) {
        double d = (ward->Location() - ship->Location()).length();
        double safe_zone = 50e3;

        if (target) {
            if (ship->IsStarship())
            safe_zone = 100e3;

            if (d > safe_zone) {
                ship_ai->DropTarget();
                return;
            }
        }
        else {
            if (d > safe_zone) {
                return;
            }
        }
    }

    // already have a target, keep it:
    if (target) {
        if (target->Life()) {
            CheckTarget();

            // frigates need to be ready to abandon ship-type targets
            // in favor of drone-type targets, others should just go
            // with what they have:
            if (ship->Class() != Ship::CORVETTE && ship->Class() != Ship::FRIGATE)
            return;

            // in case the check decided to drop the target:
            target = ship_ai->GetTarget();
        }

        // if the old target is dead, forget it:
        else {
            ship_ai->DropTarget();
            target = 0;
        }
    }

    // if not allowed to acquire, forget it:
    if (ship_ai->DropTime() > 0)
    return;

    if (roe == DIRECTED) {
        if (target && target->Type() == SimObject::SIM_SHIP)
        SelectTargetDirected((Ship*) target);
        else if (navpt && navpt->GetTarget() && navpt->GetTarget()->Type() == SimObject::SIM_SHIP)
        SelectTargetDirected((Ship*) navpt->GetTarget());
        else
        SelectTargetDirected();
    }

    else {
        SelectTargetOpportunity();

        // don't switch one ship target for another...
        if (ship->Class() == Ship::CORVETTE || ship->Class() == Ship::FRIGATE) {
            SimObject* potential_target = ship_ai->GetTarget();
            if (target && potential_target && target != potential_target) {
                if (target->Type()           == SimObject::SIM_SHIP &&
                        potential_target->Type() == SimObject::SIM_SHIP) {

                    ship_ai->SetTarget(target);
                }
            }
        }
    }
}