Ejemplo n.º 1
0
void CivilianBAIState::setupEscape()
{
	int unitsSpottingMe = getSpottingUnits(_unit->getPosition());
	int currentTilePreference = 15;
	int tries = 0;
	bool coverFound = false;
	selectNearestTarget();

	int dist = _aggroTarget ? _save->getTileEngine()->distance(_unit->getPosition(), _aggroTarget->getPosition()) : 0;

	int bestTileScore = -100000;
	int score = -100000;
	Position bestTile(0, 0, 0);

	Tile *tile = 0;
	
	// weights of various factors in choosing a tile to which to withdraw
	const int EXPOSURE_PENALTY = 10;
	const int FIRE_PENALTY = 40;
	const int BASE_SYSTEMATIC_SUCCESS = 100;
	const int BASE_DESPERATE_SUCCESS = 110;
	const int FAST_PASS_THRESHOLD = 100; // a score that's good engouh to quit the while loop early; it's subjective, hand-tuned and may need tweaking

	int tu = _unit->getTimeUnits() / 2;

	std::vector<int> reachable = _save->getPathfinding()->findReachable(_unit, tu);
	std::vector<Position> randomTileSearch = _save->getTileSearch();
	RNG::shuffle(randomTileSearch);
	
	while (tries < 150 && !coverFound)
	{
		_escapeAction->target = _unit->getPosition(); // start looking in a direction away from the enemy
					
		if (!_save->getTile(_escapeAction->target))
		{
			_escapeAction->target = _unit->getPosition(); // cornered at the edge of the map perhaps? 
		}
		
		score = 0;

		if (tries < 121) 
		{
			// looking for cover
			_escapeAction->target.x += randomTileSearch[tries].x;
			_escapeAction->target.y += randomTileSearch[tries].y;
			score = BASE_SYSTEMATIC_SUCCESS;
			if (_escapeAction->target == _unit->getPosition()) 
			{
				if (unitsSpottingMe > 0)
				{
					// maybe don't stay in the same spot? move or something if there's any point to it?
					_escapeAction->target.x += RNG::generate(-20,20);
					_escapeAction->target.y += RNG::generate(-20,20);
				} else
				{
					score += currentTilePreference;
				}
			}
		}
		else
		{
			
			if (tries == 121) 
			{ 
				if (_traceAI) 
				{
					Log(LOG_INFO) << "best score after systematic search was: " << bestTileScore; 
				}
			}
						
			score = BASE_DESPERATE_SUCCESS; // ruuuuuuun
			_escapeAction->target = _unit->getPosition();
			_escapeAction->target.x += RNG::generate(-10,10);
			_escapeAction->target.y += RNG::generate(-10,10);
			_escapeAction->target.z = _unit->getPosition().z + RNG::generate(-1,1);
			if (_escapeAction->target.z < 0)
			{
				_escapeAction->target.z = 0;
			}
			else if (_escapeAction->target.z >= _save->getMapSizeZ()) 
			{
				_escapeAction->target.z = _unit->getPosition().z;
			}
		}

		tries += 10; // civilians shouldn't have any tactical sense anyway so save some CPU cycles here

		// THINK, DAMN YOU
		tile = _save->getTile(_escapeAction->target);
		int distanceFromTarget = _aggroTarget ? _save->getTileEngine()->distance(_aggroTarget->getPosition(), _escapeAction->target) : 0;
		if (dist >= distanceFromTarget)
		{
			score -= (distanceFromTarget - dist) * 10;
		}
		else
		{
			score += (distanceFromTarget - dist) * 10;
		}
		int spotters = 0;
		if (!tile) 
		{
			score = -100001; // no you can't quit the battlefield by running off the map. 
		}
		else
		{
			spotters = getSpottingUnits(_escapeAction->target);
			if (std::find(reachable.begin(), reachable.end(), _save->getTileIndex(tile->getPosition()))  == reachable.end()) continue; // just ignore unreachable tiles
					
			if (_spottingEnemies || spotters)
			{
				if (_spottingEnemies <= spotters)
				{
					score -= (1 + spotters - _spottingEnemies) * EXPOSURE_PENALTY; // that's for giving away our position
				}
				else
				{
					score += (_spottingEnemies - spotters) * EXPOSURE_PENALTY;
				}
			}
			if (tile->getFire())
			{
				score -= FIRE_PENALTY;
			}
			if (_traceAI)
			{
				tile->setMarkerColor(score < 0 ? 3 : (score < FAST_PASS_THRESHOLD/2 ? 8 : (score < FAST_PASS_THRESHOLD ? 9 : 5)));
				tile->setPreview(10);
				tile->setTUMarker(score);
			}

		}

		if (tile && score > bestTileScore)
		{
			// calculate TUs to tile; we could be getting this from findReachable() somehow but that would break something for sure...
			_save->getPathfinding()->calculate(_unit, _escapeAction->target, 0, tu);
			if (_escapeAction->target == _unit->getPosition() || _save->getPathfinding()->getStartDirection() != -1)
			{
				bestTileScore = score;
				bestTile = _escapeAction->target;
				_escapeTUs = _save->getPathfinding()->getTotalTUCost();
				if (_escapeAction->target == _unit->getPosition())
				{
					_escapeTUs = 1;
				}
				if (_traceAI)
				{
					tile->setMarkerColor(score < 0 ? 7 : (score < FAST_PASS_THRESHOLD/2 ? 10 : (score < FAST_PASS_THRESHOLD ? 4 : 5)));
					tile->setPreview(10);
					tile->setTUMarker(score);
				}
			}
			_save->getPathfinding()->abortPath();
			if (bestTileScore > FAST_PASS_THRESHOLD) coverFound = true; // good enough, gogogo
		}
	}
	_escapeAction->target = bestTile;
	if (_traceAI)
	{
		_save->getTile(_escapeAction->target)->setMarkerColor(13);
	}
				
	if (bestTileScore <= -100000) 
	{
		if (_traceAI)
		{
			Log(LOG_INFO) << "Escape estimation failed.";
		}
		_escapeAction->type = BA_RETHINK; // do something, just don't look dumbstruck :P
		return;
	}
	else
	{
		if (_traceAI)
		{
			Log(LOG_INFO) << "Escape estimation completed after " << tries << " tries, " << _save->getTileEngine()->distance(_unit->getPosition(), bestTile) << " squares or so away.";
		}
		_escapeAction->type = BA_WALK;
	}
}
Ejemplo n.º 2
0
/**
 * Runs any code the state needs to keep updating every
 * AI cycle.
 * @param action (possible) AI action to execute after thinking is done.
 */
void AggroBAIState::think(BattleAction *action)
{
	if (Options::getBool("traceAI")) { Log(LOG_INFO) << "AggroBAIState::think() #" << action->number << (charge ? " [charging]": " "); }
	
 	action->type = BA_RETHINK;
	action->actor = _unit;
	/* Aggro is mainly either shooting a target or running towards it (melee).
	   If we do no action here - we assume we lost aggro and will go back to patrol state.
	*/
	int aggression = _unit->getAggression();
	if (!charge || (_aggroTarget && (_aggroTarget->isOut() || _aggroTarget->getFaction() == _unit->getFaction()))) 
	{
		_aggroTarget = 0;
	} else
	{
		action->type = BA_WALK; // just in case
		action->target = _lastKnownPosition;
	}
	int unitsSpottingMe = _game->getSpottingUnits(_unit);


	/*	psionic targetting: pick from any of the "exposed" units.
		exposed means they have been previously spotted, and are therefore "known" to the AI,
		regardless of whether we can see them or not, because we're psychic.
	*/
	if (_unit->getStats()->psiSkill && _unit->getType() != "SOLDIER" && _game->getExposedUnits()->size() > 0 && RNG::generate(0, 100) > 66)
	{
		int psiAttackStrength = _unit->getStats()->psiSkill * _unit->getStats()->psiStrength / 50;
		int chanceToAttack = 0;
		int tries = 0;
		for (std::vector<BattleUnit*>::const_iterator i = _game->getExposedUnits()->begin(); i != _game->getExposedUnits()->end() && tries < 80; ++i)
		{
			// don't target tanks
			if ((*i)->getArmor()->getSize() != 2)
			{
				int chanceToAttackMe = psiAttackStrength
					+ ((*i)->getStats()->psiSkill * -0.4)
					- (_game->getTileEngine()->distance(_unit->getPosition(), (*i)->getPosition()) / 2)
					- ((*i)->getStats()->psiStrength)
					+ (RNG::generate(0, 50))
					+ 55;

				if (chanceToAttackMe > chanceToAttack)
				{
					chanceToAttack = chanceToAttackMe;
					_aggroTarget = *i;
				}
			}
			++tries;
		}

		if (!_aggroTarget)
			chanceToAttack = 0;

		if (chanceToAttack)
		{
			if (_unit->getMainHandWeapon() && _unit->getMainHandWeapon()->getAmmoItem())
			{
				if (_unit->getMainHandWeapon()->getAmmoItem()->getRules()->getPower() >= chanceToAttack)
				{
					chanceToAttack = 0;
					_aggroTarget = 0;
				}
			}
			else
			{
				if (RNG::generate(35, 155) >= chanceToAttack)
				{
					chanceToAttack = 0;
					_aggroTarget = 0;
				}
			}
			if (chanceToAttack >= 30)
			{
				int controlOrPanic = 60;
				int morale = _aggroTarget->getMorale();
				int bravery = _aggroTarget->getStats()->bravery;
				if (bravery > 60)
					controlOrPanic += 15;
				if ( bravery < 40)
					controlOrPanic -= 15;
				if (morale >= 40)
				{
					if (morale - 10 * bravery < 50)
						controlOrPanic += 15;
				}
				else
				{
					controlOrPanic -= 15;
				}
				if (!morale)
				{
					controlOrPanic = 0;
				}
				if (RNG::generate(0, 100) >= controlOrPanic)
				{
					action->type = BA_MINDCONTROL;
					action->target = _aggroTarget->getPosition();
				}
				else
				{
					action->type = BA_PANIC;
					action->target = _aggroTarget->getPosition();
				}
			}
			else if (chanceToAttack)
			{
					action->type = BA_PANIC;
					action->target = _aggroTarget->getPosition();
			}
		}
	}

	
	/*	
	*	waypoint targetting: pick from any units currently spotted by our allies.
	*/
	if (_unit->getMainHandWeapon() && _unit->getMainHandWeapon()->getAmmoItem() && _unit->getMainHandWeapon()->getRules()->isWaypoint() && _unit->getType() != "SOLDIER")
	{
		for (std::vector<BattleUnit*>::const_iterator i = _game->getUnits()->begin(); i != _game->getUnits()->end() && _aggroTarget == 0; ++i)
		{
			if ((*i)->getFaction() == _unit->getFaction())
			{
				for (std::vector<BattleUnit*>::const_iterator j = (*i)->getVisibleUnits()->begin(); j != (*i)->getVisibleUnits()->end() && _aggroTarget == 0; ++j)
				{
					_game->getPathfinding()->calculate(_unit, (*j)->getPosition(), *j);
					if (_game->getPathfinding()->getStartDirection() != -1 && explosiveEfficacy((*j)->getPosition(), _unit, (_unit->getMainHandWeapon()->getAmmoItem()->getRules()->getPower()/20)+1, action->diff))
					{
						_aggroTarget = *j;
					}
					_game->getPathfinding()->abortPath();
				}
			}
		}

		if (_aggroTarget != 0)
		{
			action->weapon = _unit->getMainHandWeapon();
			action->type = BA_LAUNCH;
			action->TU = action->actor->getActionTUs(action->type, action->weapon);
			action->waypoints.clear();

			int PathDirection;
			int CollidesWith;
			Position LastWayPoint = _unit->getPosition();
			Position LastPosition = _unit->getPosition();
			Position CurrentPosition = _unit->getPosition();
			Position DirectionVector;

			_game->getPathfinding()->calculate(_unit, _aggroTarget->getPosition(), _aggroTarget);
			PathDirection = _game->getPathfinding()->dequeuePath();
			while (PathDirection != -1)
			{
				LastPosition = CurrentPosition;
				_game->getPathfinding()->directionToVector(PathDirection, &DirectionVector);
				CurrentPosition = CurrentPosition + DirectionVector;
				Position voxelPosA ((CurrentPosition.x * 16)+8, (CurrentPosition.y * 16)+8, (CurrentPosition.z * 24)+12);
				Position voxelPosb ((LastWayPoint.x * 16)+8, (LastWayPoint.y * 16)+8, (LastWayPoint.z * 24)+12);
				CollidesWith = _game->getTileEngine()->calculateLine(voxelPosA, voxelPosb, false, 0, _unit, true);
				if (CollidesWith > -1 && CollidesWith < 4)
				{
					action->waypoints.push_back(LastPosition);
					LastWayPoint = LastPosition;
				}
				else if (CollidesWith == 4)
				{
					BattleUnit* target = _game->getTile(CurrentPosition)->getUnit();
					if (target == _aggroTarget)
					{
						action->waypoints.push_back(CurrentPosition);
						LastWayPoint = CurrentPosition;
					}
				}

				PathDirection = _game->getPathfinding()->dequeuePath();
			}
			action->target = action->waypoints.front();
			if( action->waypoints.size() > 6 + (action->diff * 2) || LastWayPoint != _aggroTarget->getPosition())
			{
				action->type = BA_RETHINK;
			}
		}
	}


	/*
	 *	Regular targetting: we can see an enemy, or an enemy can see us (in case we need to take cover), or we're charging blindly toward an enemy we're pretty sure is there
	 */
	if (_unit->getVisibleUnits()->size() > 0 || unitsSpottingMe || charge)
	{
		for (std::vector<BattleUnit*>::iterator j = _unit->getVisibleUnits()->begin(); j != _unit->getVisibleUnits()->end(); ++j)
		{
			//pick closest living unit
			if (!_aggroTarget || _game->getTileEngine()->distance(_unit->getPosition(), (*j)->getPosition()) < _game->getTileEngine()->distance(_unit->getPosition(), _aggroTarget->getPosition()))
			{
				if(!(*j)->isOut())
					_aggroTarget = (*j);
			}
		}
	
		// if we currently see no target, we either can move to it's last seen position or lose aggro
		if (_aggroTarget == 0 && _lastKnownTarget != 0)
		{
			_timesNotSeen++;
			if (_timesNotSeen > _unit->getIntelligence() || aggression == 0)
			{
				// we lost aggro - going back to patrol state
				charge = 0;
				_unit->setCharging(0);
				return;
			}
			// lets go looking where we've last seen him
			action->type = BA_WALK;
			action->target = _lastKnownPosition;
		}
		else if (_aggroTarget != 0)
		{
			// if we see the target, we either can shoot him, or take cover.
			bool takeCover = true;
			if (!charge)
			{
				_unit->setCharging(0);
			} else
			{
				_unit->setCharging(_aggroTarget);
			}
			int number = RNG::generate(0,100);

			// extra 5% chance per unit that sees us
			number += unitsSpottingMe * 5;

			// lost health, chances to take cover get bigger
			if (_unit->getHealth() < _unit->getStats()->health)
				number += 10;

			// aggrotarget has no weapon - chances of take cover get smaller
			if (!_aggroTarget->getMainHandWeapon())
				number -= 50;
			if (aggression == 0 && number < 10)
				takeCover = false;
			if (aggression == 1 && number < 50)
				takeCover = false;
			if (aggression == 2 && number < 90)
				takeCover = false;

			// we're using melee, so CHAAAAAAAARGE!!!!!
			if (_unit->getMainHandWeapon() && _unit->getMainHandWeapon()->getRules()->getBattleType() == BT_MELEE)
			{
				_unit->lookAt(_aggroTarget->getPosition() + Position(_unit->getArmor()->getSize()-1, _unit->getArmor()->getSize()-1, 0), false);
				while (_unit->getStatus() == STATUS_TURNING)
					_unit->turn();
				if (_game->getTileEngine()->validMeleeRange(_unit, _aggroTarget))
				{
					if (Options::getBool("traceAI")) { Log(LOG_INFO) << "Rawr!"; }
					action->target = _aggroTarget->getPosition();
					action->weapon = action->actor->getMainHandWeapon();
					action->type = BA_HIT;
					charge = true;
				}
				else
				{
					takeCover = true;
					bool targetFound = false;
					int distance = 200;
					int size = action->actor->getArmor()->getSize(); //-1;
					int targetsize = _aggroTarget->getArmor()->getSize(); //-1;
					for (int x = 0 - size; x <= targetsize; ++x)
					{
						for (int y = 0 - size; y <= targetsize; ++y)
						{
							if (!(x == 0 && y == 0))
							{
								Position checkPath = _aggroTarget->getPosition() + Position (x, y, 0);
								_game->getPathfinding()->calculate(action->actor, checkPath, 0);
								int newDistance = _game->getTileEngine()->distance(action->actor->getPosition(), checkPath);
								bool valid = _game->getTileEngine()->validMeleeRange(checkPath, -1, action->actor->getArmor()->getSize(), action->actor->getHeight(), _aggroTarget);
								if (_game->getPathfinding()->getStartDirection() != -1  &&  valid  &&
									newDistance < distance)
								{
									// CHAAAAAAARGE!
									if (Options::getBool("traceAI")) { Log(LOG_INFO) << "CHAAAAAAARGE!"; }
									action->target = checkPath;
									action->type = BA_WALK;
									charge = true;
									_unit->setCharging(_aggroTarget);
									distance = newDistance;
								}
								_game->getPathfinding()->abortPath();
							}
						}
					}
				}
			}

			if (action->number >= 3 && !charge)
			{
				if (_unit->_hidingForTurn)
				{
					// already tried to get to cover; stay still
					action->target = _unit->getPosition();
					action->TU = 0;
					return;
				}
				
                takeCover = true; // always seek cover as last action (unless melee... charge, stupid reapers!)
                action->reckless = true;
			}

			if (!takeCover && !charge)
			{
				_timesNotSeen = 0;
				_lastKnownPosition = _aggroTarget->getPosition();
				action->target = _aggroTarget->getPosition();
				action->type = BA_NONE;

				// lets' evaluate if we could throw a grenade
				int tu = 4; // 4TUs for picking up the grenade

				// do we have a grenade on our belt?
				BattleItem *grenade = _unit->getGrenadeFromBelt();
				// distance must be more than X tiles, otherwise it's too dangerous to play with explosives
				if (grenade && explosiveEfficacy(_aggroTarget->getPosition(), _unit, (grenade->getRules()->getPower()/10)+1, action->diff))
				{
					if((_unit->getFaction() == FACTION_NEUTRAL && _aggroTarget->getFaction() == FACTION_HOSTILE) || _unit->getFaction() == FACTION_HOSTILE)
					{
						action->weapon = grenade;
						tu += _unit->getActionTUs(BA_PRIME, grenade);
						tu += _unit->getActionTUs(BA_THROW, grenade);
						// do we have enough TUs to prime and throw the grenade?
						if (tu <= _unit->getStats()->tu)
						{
							// are we within range?
							if (ProjectileFlyBState::validThrowRange(action))
							{
								grenade->setExplodeTurn(_game->getTurn());
								_unit->spendTimeUnits(_unit->getActionTUs(BA_PRIME, grenade));
								action->type = BA_THROW;
							}
						}
					}
				}

				if (action->type == BA_NONE)
				{
					action->weapon = action->actor->getMainHandWeapon();
					// out of ammo or no weapon or ammo at all, we have to take cover
					if (!action->weapon)
					{
						takeCover = true;
					}
					else
					{
						if(action->weapon->getAmmoItem() && ((_unit->getFaction() == FACTION_NEUTRAL && _aggroTarget->getFaction() == FACTION_HOSTILE) || _unit->getFaction() == FACTION_HOSTILE))
						{
							if (action->weapon->getAmmoItem()->getRules()->getDamageType() != DT_HE || explosiveEfficacy(_aggroTarget->getPosition(), _unit, (action->weapon->getAmmoItem()->getRules()->getPower() / 10) +1, action->diff))
							{
								if (RNG::generate(1,10) < 5 && action->weapon->getAmmoQuantity() > 2)
								{
									action->type = BA_AUTOSHOT;
								}
								else
								{
									action->type = BA_SNAPSHOT;
								}
							}
							tu = action->actor->getActionTUs(action->type, action->weapon);
							// enough time units to shoot?
							if (tu > _unit->getTimeUnits())
							{
								takeCover = true;
							}
						}
						else
							takeCover = true;
					}
				}
			}


			if (takeCover && !charge)
			{
				// the idea is to check within a 11x11 tile square for a tile which is not seen by our aggroTarget
				// if there is no such tile, we run away from the target.
				action->type = BA_WALK;
				_unit->_hidingForTurn = true;
				int tries = 0;
				bool coverFound = false;
				int x_search_sign = RNG::generate(0, 1) ? 1 : -1; // randomize the direction of the search for lack of a better heuristic
				int y_search_sign = RNG::generate(0, 1) ? 1 : -1;
				int dx = _unit->getPosition().x - _aggroTarget->getPosition().x; // 2d vector in the direction away from the aggro target
				int dy = _unit->getPosition().y - _aggroTarget->getPosition().y;
				int dist = _game->getTileEngine()->distance(_unit->getPosition(), _aggroTarget->getPosition());
                Vector3i run;
				run.x = (dx * 5) / dist;
				run.y = (dy * 5) / dist;
                run.z = 0;
				
				int bestTileScore = -100000;
				int score = -100000;
				Position bestTile(0, 0, 0);
                ++_randomTileSearchAge;
				if (action->number > 1) action->desperate = true;
				
				Tile *tile = 0;
				
				bool traceSpammed = false;
				
				// weights of various factors in choosing a tile to which to withdraw
				const int EXPOSURE_PENALTY = 20;
				const int WINDOW_PENALTY = 30;
				const int WALL_BONUS = 1;
				const int FIRE_PENALTY = 40;
				const int FRIEND_BONUS = 10;
				const int SMOKE_PENALTY = 5;
				const int OVERREACH_PENALTY = EXPOSURE_PENALTY*3;
				const int MELEE_TUNNELVISION_BONUS = 1000;
				const int DIRECT_PATH_PENALTY = 10;
				const int DIRECT_PATH_TO_TARGET_PENALTY = 30;
				const int BASE_SYSTEMATIC_SUCCESS = 100;
				const int BASE_DESPERATE_SUCCESS = 110;
				const int FAST_PASS_THRESHOLD = 120; // a score that's good engouh to quit the while loop early; it's subjective, hand-tuned and may need tweaking
				const int MAX_ALLY_DISTANCE = 25; // distance^2 actually
				const int MIN_ALLY_DISTANCE = 4; // don't clump up too much and get grenaded, OK?
				const int ALLY_BONUS = 4;
				
				while (tries < 150 && !coverFound)
				{
					tries++;
					action->target = _unit->getPosition() + run; // start looking in a direction away from the enemy
					
					if (!_game->getTile(action->target))
					{
						action->target = _unit->getPosition(); // cornered at the edge of the map perhaps? 
					}
					
					if (tries < 121) 
					{
						// looking for cover
						action->target.x += _randomTileSearch[tries].x;
						action->target.y += _randomTileSearch[tries].y;
						if (action->target == _unit->getPosition() && action->number == 1 &&  unitsSpottingMe > 0)
						{
							// don't even think about staying in the same spot. Move!
							action->target.x += RNG::generate(-20,20);
							action->target.y += RNG::generate(-20,20);
						}
						//score = _game->getTileEngine()->visible(_aggroTarget, _game->getTile(action->target)) ? 0 : 100;
						score = BASE_SYSTEMATIC_SUCCESS; // no need for visible here, the TileEngine code will take care of it
					}
					else
					{
                        if (tries == 121) 
						{ 
							action->reckless = true; 
							if (Options::getBool("traceAI")) 
							{
								Log(LOG_INFO) << _unit->getId() << " best score after systematic search was: " << bestTileScore; 
							}
						}
						
						score = BASE_DESPERATE_SUCCESS; // ruuuuuuun
                        action->target = _unit->getPosition() + run*3;
						action->target.x += RNG::generate(-10,10);
						action->target.y += RNG::generate(-10,10);
						action->target.z = _unit->getPosition().z + RNG::generate(-1,1);
						if (action->target.z < 0)
                        {
                            action->target.z = 0;
                        }
                        else if (action->target.z >= _game->getMapSizeZ()) 
                        {
                            action->target.z = _unit->getPosition().z;
                        }
					}

					// THINK, DAMN YOU
					tile = _game->getTile(action->target);
					if (!tile) 
					{
						score = -100000; // no you can't quit the battlefield by running off the map. 
					}
					else
					{
						_game->getTileEngine()->surveyXComThreatToTile(tile, action->target, _unit);
						
						if (tile->soldiersVisible == -1) continue; // you can't go there.
						
						if (tile->soldiersVisible && tile->closestSoldierDSqr <= 100 && tile->closestSoldierDSqr > 0) 
						{
							score -= (100/tile->closestSoldierDSqr);
						}
						
						if (tile->soldiersVisible && tile->meanSoldierDSqr <= 200 && tile->meanSoldierDSqr > 0) 
						{
							score -= (50/tile->meanSoldierDSqr); // less important than above
						}
						
						//if (!tile->_soldiersVisible) { Log(LOG_WARNING) << "No soldiers visible? Really?"; }
						
						if (!tile->soldiersVisible)
						{
							score += dist*4; // hooray! (4 because it's about 4 TUs to walk a tile?)
						} else
						{						
							score -= tile->soldiersVisible * EXPOSURE_PENALTY;
							score += (dist > 9) ? 4 : dist; 
						}
						
						if (_unit->getMainHandWeapon() && _unit->getMainHandWeapon()->getRules()->getBattleType() == BT_MELEE
							 && _unit->getUnitRules() && _unit->getHealth() > _unit->getStats()->health/2)
						{
							// did you say "not charge?" KOMPRESSOR BREAK YOUR GLOWSTICK AND KOMPRESSOR EAT YOUR CANDY
							score -= (dist-1) * MELEE_TUNNELVISION_BONUS;
							if (score < -90000) score = -90000;
							charge = true;
							if (Options::getBool("traceAI") && !traceSpammed) { Log(LOG_INFO) << "Trying to get melee unit to do something."; traceSpammed = true; }
						}
						
						// strength in numbers but not in "grenade us!" huddles:
						if (tile->closestAlienDSqr < MAX_ALLY_DISTANCE && tile->closestAlienDSqr > MIN_ALLY_DISTANCE) score += ALLY_BONUS;
						if (tile->closestAlienDSqr <= MIN_ALLY_DISTANCE) score -= ALLY_BONUS;
						
						_game->getPathfinding()->setUnit(_unit); // because we can't just pass this around as a paramater, can we... no, that would be too simple
						
						if (tile->soldiersVisible && _game->getPathfinding()->bresenhamPath(tile->_closestSoldierPos, action->target, 0, false))
						{
							score -= DIRECT_PATH_TO_TARGET_PENALTY; // not even partial cover?
						}
						_game->getPathfinding()->abortPath(); // clean up hypothetical path data
						
						if (_game->getPathfinding()->bresenhamPath(_aggroTarget->getPosition(), action->target, 0, false)) score -= DIRECT_PATH_PENALTY; // come on partial cover?
						_game->getPathfinding()->abortPath();						
						
						if (tile->getFire()) score -= FIRE_PENALTY; // maybe stop, drop, and roll?
						
						if (tile->getSmoke()) score -= SMOKE_PENALTY; // *cough* *cough*
						
						if (tile->getMapData(MapData::O_NORTHWALL) || tile->getMapData(MapData::O_WESTWALL)) score += WALL_BONUS; // hug the walls
						
						if (_game->getTileEngine()->faceWindow(action->target) != -1) score -= WINDOW_PENALTY; // a window is not cover.
					}


					if (score > bestTileScore)
					{
						// check if we can reach this tile
						_game->getPathfinding()->calculate(_unit, action->target);
						if (_game->getPathfinding()->getTotalTUCost() > _unit->getTimeUnits())
						{
							score -= OVERREACH_PENALTY; // not gonna make it
						} else
						{
							if (tile->soldiersVisible == 0) score += _unit->getTimeUnits() - _game->getPathfinding()->getTotalTUCost(); // conserve TU if possible
						}
						if (score > bestTileScore && _game->getPathfinding()->getStartDirection() != -1)
						{
							// yay, we can get there and the overreach penalty didn't kill the score
							bestTileScore = score;
							bestTile = action->target;
						}
						_game->getPathfinding()->abortPath();
						if (bestTileScore > FAST_PASS_THRESHOLD) coverFound = true; // good enough, gogogo
					}
				}
				if (Options::getBool("traceAI"))
				{
					Log(LOG_INFO) << _unit->getId() << " Taking cover with score " << bestTileScore << " after " << tries << " tries, at a tile spotted by " << ((tile=_game->getTile(bestTile)) ? tile->soldiersVisible : -666) << ". Action #" << action->number;
					//Log(LOG_INFO) << "Walking " << _game->getTileEngine()->distance(_unit->getPosition(), bestTile) << " squares or so.";

				}
				action->target = bestTile;
				
				if (_aggroTarget != 0)
					setAggroTarget(_aggroTarget);

				
				if (score <= -100000) 
				{
					coverFound = false;
					action->type = BA_NONE;
					action->TU = 0;
					return;
				}
			}
		}
		if (action->type != BA_RETHINK && action->type != BA_WALK)
			action->TU = action->actor->getActionTUs(action->type, action->weapon);
	}
	if (_aggroTarget != 0)
		setAggroTarget(_aggroTarget);
	if (charge)
		action->desperate = true;
}