예제 #1
0
void MainPanel::Draw() const
{
	FrameTimer loadTimer;
	glClear(GL_COLOR_BUFFER_BIT);
	
	engine.Draw();
	
	if(Preferences::Has("Show CPU / GPU load"))
	{
		string loadString = to_string(static_cast<int>(load * 100. + .5)) + "% GPU";
		Color color = *GameData::Colors().Get("medium");
		FontSet::Get(14).Draw(loadString, Point(10., Screen::Height() * -.5 + 5.), color);
	
		loadSum += loadTimer.Time();
		if(++loadCount == 60)
		{
			load = loadSum;
			loadSum = 0.;
			loadCount = 0;
		}
	}
}
예제 #2
0
void MainPanel::Draw()
{
	FrameTimer loadTimer;
	glClear(GL_COLOR_BUFFER_BIT);
	
	engine.Draw();
	
	if(isDragging)
	{
		if(canDrag)
		{
			const Color &dragColor = *GameData::Colors().Get("drag select");
			LineShader::Draw(dragSource, Point(dragSource.X(), dragPoint.Y()), .8f, dragColor);
			LineShader::Draw(Point(dragSource.X(), dragPoint.Y()), dragPoint, .8f, dragColor);
			LineShader::Draw(dragPoint, Point(dragPoint.X(), dragSource.Y()), .8f, dragColor);
			LineShader::Draw(Point(dragPoint.X(), dragSource.Y()), dragSource, .8f, dragColor);
		}
		else
			isDragging = false;
	}
	
	if(Preferences::Has("Show CPU / GPU load"))
	{
		string loadString = to_string(lround(load * 100.)) + "% GPU";
		const Color &color = *GameData::Colors().Get("medium");
		FontSet::Get(14).Draw(loadString, Point(10., Screen::Height() * -.5 + 5.), color);
	
		loadSum += loadTimer.Time();
		if(++loadCount == 60)
		{
			load = loadSum;
			loadSum = 0.;
			loadCount = 0;
		}
	}
}
예제 #3
0
void Engine::CalculateStep()
{
	FrameTimer loadTimer;
	
	// Clear the list of objects to draw.
	draw[calcTickTock].Clear(step);
	radar[calcTickTock].Clear();
	
	if(!player.GetSystem())
		return;
	
	// Now, all the ships must decide what they are doing next.
	ai.Step(ships, player);
	const Ship *flagship = player.Flagship();
	bool wasHyperspacing = (flagship && flagship->IsEnteringHyperspace());
	
	// Now, move all the ships. We must finish moving all of them before any of
	// them fire, or their turrets will be targeting where a given ship was
	// instead of where it is now. This is also where ships get deleted, and
	// where they may create explosions if they are dying.
	for(auto it = ships.begin(); it != ships.end(); )
	{
		// Give the ship the list of effects so that if it is dying, it can
		// create explosions. Eventually ships might create other effects too.
		// Note that engine flares are handled separately, so that they will be
		// drawn immediately under the ship.
		if(!(*it)->Move(effects))
			it = ships.erase(it);
		else
		{
			// Boarding:
			bool autoPlunder = !(*it)->GetGovernment()->IsPlayer();
			shared_ptr<Ship> victim = (*it)->Board(autoPlunder);
			if(victim)
				eventQueue.emplace_back(*it, victim,
					(*it)->GetGovernment()->IsEnemy(victim->GetGovernment()) ?
						ShipEvent::BOARD : ShipEvent::ASSIST);
			++it;
		}
	}
	
	if(!wasHyperspacing && flagship && flagship->IsEnteringHyperspace())
		Audio::Play(Audio::Get(flagship->Attributes().Get("jump drive") ? "jump_drive" : "hyperspace"));
	
	// If the player has entered a new system, update the asteroids, etc.
	if(wasHyperspacing && !flagship->IsEnteringHyperspace())
	{
		doFlash = true;
		EnterSystem();
	}
	else if(flagship && player.GetSystem() != flagship->GetSystem())
	{
		// Wormhole travel:
		player.ClearTravel();
		doFlash = true;
		EnterSystem();
	}
	
	// Now we know the player's current position. Draw the planets.
	Point center;
	Point centerVelocity;
	if(flagship)
	{
		center = flagship->Position();
		centerVelocity = flagship->Velocity();
	}
	else if(player.GetPlanet())
	{
		for(const StellarObject &object : player.GetSystem()->Objects())
			if(object.GetPlanet() == player.GetPlanet())
				center = object.Position();
	}
	if(!flagship)
		doClick = false;
	
	for(const StellarObject &object : player.GetSystem()->Objects())
		if(!object.GetSprite().IsEmpty())
		{
			Point position = object.Position();
			Point unit = object.Unit();
			position -= center;
			
			int type = object.IsStar() ? Radar::SPECIAL :
				!object.GetPlanet() ? Radar::INACTIVE :
				object.GetPlanet()->IsWormhole() ? Radar::ANOMALOUS :
				object.GetPlanet()->CanLand() ? Radar::FRIENDLY : Radar::HOSTILE;
			double r = max(2., object.Radius() * .03 + .5);
			
			// Don't apply motion blur to very large planets and stars.
			bool isBig = (object.GetSprite().Width() >= 280);
			draw[calcTickTock].Add(object.GetSprite(), position, unit, isBig ? Point() : -centerVelocity);
			radar[calcTickTock].Add(type, position, r, r - 1.);
			
			if(doClick && object.GetPlanet() && (clickPoint - position).Length() < object.Radius())
				player.Flagship()->SetTargetPlanet(&object);
		}
	
	// Add all neighboring systems to the radar.
	const System *targetSystem = flagship ? flagship->GetTargetSystem() : nullptr;
	for(const System *system : player.GetSystem()->Links())
		radar[calcTickTock].AddPointer(
			(system == targetSystem) ? Radar::SPECIAL : Radar::INACTIVE,
			system->Position() - player.GetSystem()->Position());
	
	// Now that the planets have been drawn, we can draw the asteroids on top
	// of them. This could be done later, as long as it is done before the
	// collision detection.
	asteroids.Step();
	asteroids.Draw(draw[calcTickTock], center, centerVelocity);
	
	// Move existing projectiles. Do this before ships fire, which will create
	// new projectiles, since those should just stay where they are created for
	// this turn. This is also where projectiles get deleted, which may also
	// result in a "die" effect or a sub-munition being created. We could not
	// move the projectiles before this because some of them are homing and need
	// to know the current positions of the ships.
	list<Projectile> newProjectiles;
	for(auto it = projectiles.begin(); it != projectiles.end(); )
	{
		if(!it->Move(effects))
		{
			it->MakeSubmunitions(newProjectiles);
			it = projectiles.erase(it);
		}
		else
			++it;
	}
	projectiles.splice(projectiles.end(), newProjectiles);
	
	// Keep track of the relative strength of each government in this system. Do
	// not add more ships to make a winning team even stronger. This is mostly
	// to avoid having the player get mobbed by pirates, say, if they hang out
	// in one system for too long.
	map<const Government *, int64_t> strength;
	// Now, ships fire new projectiles, which includes launching fighters. If an
	// anti-missile system is ready to fire, it does not actually fire unless a
	// missile is detected in range during collision detection, below.
	vector<Ship *> hasAntiMissile;
	for(shared_ptr<Ship> &ship : ships)
		if(ship->GetSystem() == player.GetSystem())
		{
			strength[ship->GetGovernment()] += ship->Cost();
			
			// Note: if a ship "fires" a fighter, that fighter was already in
			// existence and under the control of the same AI as the ship, but
			// its system was null to mark that it was not active.
			ship->Launch(ships);
			if(ship->Fire(projectiles, effects))
				hasAntiMissile.push_back(ship.get());
			
			int scan = ship->Scan();
			if(scan)
			{
				shared_ptr<Ship> target = ship->GetTargetShip();
				if(target && target->IsTargetable())
					eventQueue.emplace_back(ship, target, scan);
			}
			
			// This is a good opportunity to draw all the ships in system.
			if(ship->GetSprite().IsEmpty())
				continue;
			
			Point position = ship->Position() - center;
			
			if(ship->IsThrusting())
			{
				for(const Point &point : ship->EnginePoints())
				{
					Point pos = ship->Facing().Rotate(point) * .5 * ship->Zoom() + position;
					for(const auto &it : ship->Attributes().FlareSprites())
						for(int i = 0; i < it.second; ++i)
						{
							if(ship->Cloaking())
							{
								draw[calcTickTock].Add(
									it.first.GetSprite(),
									pos,
									ship->Unit(),
									ship->Velocity() - centerVelocity,
									ship->Cloaking());
							}
							else
							{
								draw[calcTickTock].Add(
									it.first,
									pos,
									ship->Unit(),
									ship->Velocity() - centerVelocity);
							}
						}
				}
				if(ship.get() == flagship)
				{
					for(const auto &it : ship->Attributes().FlareSounds())
						if(it.second > 0)
							Audio::Play(it.first);
				}
			}
			
			bool isPlayer = ship->GetGovernment()->IsPlayer();
			if(ship->Cloaking())
			{
				if(isPlayer)
				{
					Animation animation = ship->GetSprite();
					animation.SetSwizzle(7);
					draw[calcTickTock].Add(
						animation,
						position,
						ship->Unit(),
						ship->Velocity() - centerVelocity);
				}
				draw[calcTickTock].Add(
					ship->GetSprite().GetSprite(),
					position,
					ship->Unit(),
					ship->Velocity() - centerVelocity,
					ship->Cloaking(),
					ship->GetSprite().GetSwizzle());
			}
			else
			{
				draw[calcTickTock].Add(
					ship->GetSprite(),
					position,
					ship->Unit(),
					ship->Velocity() - centerVelocity);
			}
			
			// Do not show cloaked ships on the radar, except the player's ships.
			if(ship->Cloaking() == 1. && !isPlayer)
				continue;
			
			if(doClick && &*ship != player.Flagship())
			{
				const Mask &mask = ship->GetSprite().GetMask(step);
				if(mask.WithinRange(clickPoint - position, ship->Facing(), 50.))
				{
					player.Flagship()->SetTargetShip(ship);
					// If we've found an enemy within the click zone, favor
					// targeting it rather than any other ship. Otherwise, keep
					// checking for hits because another ship might be an enemy.
					if(ship->GetGovernment()->IsEnemy())
						doClick = false;
				}
			}
			
			auto target = ship->GetTargetShip();
			radar[calcTickTock].Add(
				(ship->GetGovernment()->IsPlayer() || ship->GetPersonality().IsEscort()) ? Radar::PLAYER :
					(ship->IsDisabled() || ship->IsOverheated()) ? Radar::INACTIVE :
					!ship->GetGovernment()->IsEnemy() ? Radar::FRIENDLY :
					(target && target->GetGovernment()->IsPlayer()) ?
						Radar::HOSTILE : Radar::UNFRIENDLY,
				position,
				sqrt(ship->GetSprite().Width() + ship->GetSprite().Height()) * .1 + .5);
		}
	
	// Collision detection:
	for(Projectile &projectile : projectiles)
	{
		// The asteroids can collide with projectiles, the same as any other
		// object. If the asteroid turns out to be closer than the ship, it
		// shields the ship (unless the projectile has  blast radius).
		Point hitVelocity;
		double closestHit = 0.;
		shared_ptr<Ship> hit;
		const Government *gov = projectile.GetGovernment();
		
		// If this "projectile" is a ship explosion, it always explodes.
		if(gov)
		{
			closestHit = asteroids.Collide(projectile, step, &hitVelocity);
			// Projectiles can only collide with ships that are in the current
			// system and are not landing, and that are hostile to this projectile.
			for(shared_ptr<Ship> &ship : ships)
				if(ship->GetSystem() == player.GetSystem() && !ship->IsLanding() && ship->Cloaking() < 1.)
				{
					if(ship.get() != projectile.Target() && !gov->IsEnemy(ship->GetGovernment()))
						continue;
					
					// This returns a value of 0 if the projectile has a trigger
					// radius and the ship is within it.
					double range = projectile.CheckCollision(*ship, step);
					if(range < closestHit)
					{
						closestHit = range;
						hit = ship;
						hitVelocity = ship->Velocity();
					}
				}
		}
		
		if(closestHit < 1.)
		{
			// Create the explosion the given distance along the projectile's
			// motion path for this step.
			projectile.Explode(effects, closestHit, hitVelocity);
			
			// If this projectile has a blast radius, find all ships within its
			// radius. Otherwise, only one is damaged.
			if(projectile.HasBlastRadius())
			{
				// Even friendly ships can be hit by the blast.
				for(shared_ptr<Ship> &ship : ships)
					if(ship->GetSystem() == player.GetSystem() && ship->Zoom() == 1.)
						if(projectile.InBlastRadius(*ship, step))
						{
							int eventType = ship->TakeDamage(projectile, ship != hit);
							if(eventType)
								eventQueue.emplace_back(
									projectile.GetGovernment(), ship, eventType);
						}
			}
			else if(hit)
			{
				int eventType = hit->TakeDamage(projectile);
				if(eventType)
					eventQueue.emplace_back(
						projectile.GetGovernment(), hit, eventType);
			}
			
			if(hit)
				DoGrudge(hit, projectile.GetGovernment());
		}
		else if(projectile.MissileStrength())
		{
			radar[calcTickTock].Add(
				Radar::SPECIAL, projectile.Position() - center, 1.);
			
			// If the projectile did not hit anything, give the anti-missile
			// systems a chance to shoot it down.
			for(Ship *ship : hasAntiMissile)
				if(ship == projectile.Target()
						|| gov->IsEnemy(ship->GetGovernment())
						|| ship->GetGovernment()->IsEnemy(gov))
					if(ship->FireAntiMissile(projectile, effects))
					{
						projectile.Kill();
						break;
					}
		}
		else if(projectile.HasBlastRadius())
			radar[calcTickTock].Add(
				Radar::SPECIAL, projectile.Position() - center, 1.8);
		
		// Now, we can draw the projectile. The motion blur should be reduced
		// depending on how much motion blur is in the sprite itself:
		double innateVelocity = 2. * projectile.GetWeapon().Velocity();
		Point relativeVelocity = projectile.Velocity() - centerVelocity
			- projectile.Unit() * innateVelocity;
		draw[calcTickTock].Add(
			projectile.GetSprite(),
			projectile.Position() - center + .5 * projectile.Velocity(),
			projectile.Unit(),
			relativeVelocity,
			closestHit);
	}
	
	// Finally, draw all the effects, and then move them (because their motion
	// is not dependent on anything else, and this way we do all the work on
	// them in a single place.
	for(auto it = effects.begin(); it != effects.end(); )
	{
		draw[calcTickTock].Add(
			it->GetSprite(),
			it->Position() - center,
			it->Unit());
		
		if(!it->Move())
			it = effects.erase(it);
		else
			++it;
	}
	
	// Add incoming ships.
	for(const System::FleetProbability &fleet : player.GetSystem()->Fleets())
		if(!Random::Int(fleet.Period()))
		{
			const Government *gov = fleet.Get()->GetGovernment();
			if(!gov)
				continue;
			
			int64_t enemyStrength = 0;
			for(const auto &it : strength)
				if(gov->IsEnemy(it.first))
					enemyStrength += it.second;
			if(enemyStrength && strength[gov] > 2 * enemyStrength)
				continue;
			
			fleet.Get()->Enter(*player.GetSystem(), ships);
		}
	if(!Random::Int(36000))
	{
		// Loop through all persons once to see if there are any who can enter
		// this system.
		int sum = 0;
		for(const auto &it : GameData::Persons())
			sum += it.second.Frequency(player.GetSystem());
		
		if(sum)
		{
			// Adjustment factor: special persons will appear once every ten
			// minutes, but much less frequently if the game only specifies a
			// few of them. This way, they will become more common as I add
			// more, without needing to change the 10-minute constant above.
			sum = Random::Int(sum + 1000);
			for(const auto &it : GameData::Persons())
			{
				const Person &person = it.second;
				sum -= person.Frequency(player.GetSystem());
				if(sum < 0)
				{
					shared_ptr<Ship> ship = person.GetShip();
					ship->Recharge(true);
					ship->SetName(it.first);
					ship->SetGovernment(person.GetGovernment());
					ship->SetPersonality(person.GetPersonality());
					ship->SetHail(person.GetHail());
					Fleet::Enter(*player.GetSystem(), *ship);
					
					ships.push_front(ship);
					
					break;
				}
			}
		}
	}
	
	// Occasionally have some ship hail you.
	if(!Random::Int(600) && !ships.empty())
	{
		shared_ptr<Ship> source;
		unsigned i = Random::Int(ships.size());
		for(const shared_ptr<Ship> &it : ships)
			if(!i--)
			{
				source = it;
				break;
			}
		if(source->GetGovernment() && !source->GetGovernment()->IsPlayer() && !source->IsDisabled())
		{
			string message = source->GetHail();
			if(!message.empty() && source->GetSystem() == player.GetSystem())
				Messages::Add(source->GetGovernment()->GetName() + " ship \""
					+ source->Name() + "\": " + message);
		}
	}
	
	// A mouse click should only be active for a single step.
	doClick = false;
	
	// Keep track of how much of the CPU time we are using.
	loadSum += loadTimer.Time();
	if(++loadCount == 60)
	{
		load = loadSum;
		loadSum = 0.;
		loadCount = 0;
	}
}
void Engine::CalculateStep()
{
	FrameTimer loadTimer;
	
	// Clear the list of objects to draw.
	draw[calcTickTock].Clear(step);
	radar[calcTickTock].Clear();
	
	if(!player.GetSystem())
		return;
	
	// Now, all the ships must decide what they are doing next.
	ai.Step(ships, player);
	const Ship *flagship = player.Flagship();
	bool wasHyperspacing = (flagship && flagship->IsEnteringHyperspace());
	
	// Now, move all the ships. We must finish moving all of them before any of
	// them fire, or their turrets will be targeting where a given ship was
	// instead of where it is now. This is also where ships get deleted, and
	// where they may create explosions if they are dying.
	for(auto it = ships.begin(); it != ships.end(); )
	{
		int hyperspaceType = (*it)->HyperspaceType();
		bool wasHere = (flagship && (*it)->GetSystem() == flagship->GetSystem());
		bool wasHyperspacing = (*it)->IsHyperspacing();
		// Give the ship the list of effects so that it can draw explosions,
		// ion sparks, jump drive flashes, etc.
		if(!(*it)->Move(effects, flotsam))
		{
			// If Move() returns false, it means the ship should be removed from
			// play. That may be because it was destroyed, because it is an
			// ordinary ship that has been out of system for long enough to be
			// "forgotten," or because it is a fighter that just docked with its
			// mothership. Report it destroyed if that's really what happened:
			if((*it)->IsDestroyed())
				eventQueue.emplace_back(nullptr, *it, ShipEvent::DESTROY);
			it = ships.erase(it);
		}
		else
		{
			if(&**it != flagship)
			{
				// Did this ship just begin hyperspacing?
				if(wasHere && !wasHyperspacing && (*it)->IsHyperspacing())
					Audio::Play(
						Audio::Get(hyperspaceType >= 200 ? "jump out" : "hyperdrive out"),
						(*it)->Position());
				
				// Did this ship just jump into the player's system?
				if(!wasHere && flagship && (*it)->GetSystem() == flagship->GetSystem())
					Audio::Play(
						Audio::Get(hyperspaceType >= 200 ? "jump in" : "hyperdrive in"),
						(*it)->Position());
			}
			
			// Boarding:
			bool autoPlunder = !(*it)->GetGovernment()->IsPlayer();
			shared_ptr<Ship> victim = (*it)->Board(autoPlunder);
			if(victim)
				eventQueue.emplace_back(*it, victim,
					(*it)->GetGovernment()->IsEnemy(victim->GetGovernment()) ?
						ShipEvent::BOARD : ShipEvent::ASSIST);
			++it;
		}
	}
	
	if(!wasHyperspacing && flagship && flagship->IsEnteringHyperspace())
		Audio::Play(Audio::Get(flagship->HyperspaceType() >= 200 ? "jump drive" : "hyperdrive"));
	
	if(flagship && player.GetSystem() != flagship->GetSystem())
	{
		// Wormhole travel:
		if(!wasHyperspacing)
			for(const auto &it : player.GetSystem()->Objects())
				if(it.GetPlanet() && it.GetPlanet()->IsWormhole() &&
						it.GetPlanet()->WormholeDestination(player.GetSystem()) == flagship->GetSystem())
					player.Visit(it.GetPlanet());
		
		doFlash = Preferences::Has("Show hyperspace flash");
		player.SetSystem(flagship->GetSystem());
		EnterSystem();
	}
	
	// Draw the planets.
	Point newCenter = center;
	Point newCenterVelocity;
	if(flagship)
	{
		newCenter = flagship->Position();
		newCenterVelocity = flagship->Velocity();
	}
	else
		doClick = false;
	draw[calcTickTock].SetCenter(newCenter, newCenterVelocity);
	radar[calcTickTock].SetCenter(newCenter);
	
	for(const StellarObject &object : player.GetSystem()->Objects())
		if(object.HasSprite())
		{
			// Don't apply motion blur to very large planets and stars.
			if(object.Width() >= 280.)
				draw[calcTickTock].AddUnblurred(object);
			else
				draw[calcTickTock].Add(object);
			
			double r = max(2., object.Radius() * .03 + .5);
			radar[calcTickTock].Add(RadarType(object), object.Position(), r, r - 1.);
			
			if(object.GetPlanet())
				object.GetPlanet()->DeployDefense(ships);
			
			Point position = object.Position() - newCenter;
			if(doClick && object.GetPlanet() && (clickPoint - position).Length() < object.Radius())
			{
				if(&object == player.Flagship()->GetTargetPlanet())
				{
					if(!object.GetPlanet()->CanLand())
						Messages::Add("The authorities on " + object.GetPlanet()->Name() +
							" refuse to let you land.");
					else
					{
						clickCommands |= Command::LAND;
						Messages::Add("Landing on " + object.GetPlanet()->Name() + ".");
					}
				}
				else
					player.Flagship()->SetTargetPlanet(&object);
			}
		}
	
	// Add all neighboring systems to the radar.
	const System *targetSystem = flagship ? flagship->GetTargetSystem() : nullptr;
	const vector<const System *> &links = (flagship && flagship->Attributes().Get("jump drive")) ?
		player.GetSystem()->Neighbors() : player.GetSystem()->Links();
	for(const System *system : links)
		radar[calcTickTock].AddPointer(
			(system == targetSystem) ? Radar::SPECIAL : Radar::INACTIVE,
			system->Position() - player.GetSystem()->Position());
	
	// Now that the planets have been drawn, we can draw the asteroids on top
	// of them. This could be done later, as long as it is done before the
	// collision detection.
	asteroids.Step();
	asteroids.Draw(draw[calcTickTock], newCenter);
	
	// Move existing projectiles. Do this before ships fire, which will create
	// new projectiles, since those should just stay where they are created for
	// this turn. This is also where projectiles get deleted, which may also
	// result in a "die" effect or a sub-munition being created. We could not
	// move the projectiles before this because some of them are homing and need
	// to know the current positions of the ships.
	list<Projectile> newProjectiles;
	for(auto it = projectiles.begin(); it != projectiles.end(); )
	{
		if(!it->Move(effects))
		{
			it->MakeSubmunitions(newProjectiles);
			it = projectiles.erase(it);
		}
		else
			++it;
	}
	projectiles.splice(projectiles.end(), newProjectiles);
	
	// Move the flotsam, which should be drawn underneath the ships.
	for(auto it = flotsam.begin(); it != flotsam.end(); )
	{
		if(!it->Move(effects))
		{
			it = flotsam.erase(it);
			continue;
		}
		
		Ship *collector = nullptr;
		for(const shared_ptr<Ship> &ship : ships)
		{
			if(ship->GetSystem() != player.GetSystem() || ship->CannotAct())
				continue;
			if(ship.get() == it->Source() || ship->Cargo().Free() < it->UnitSize())
				continue;
			
			const Mask &mask = ship->GetMask(step);
			if(mask.Contains(it->Position() - ship->Position(), ship->Facing()))
			{
				collector = ship.get();
				break;
			}
		}
		if(collector)
		{
			string name;
			if(collector->IsYours())
			{
				if(collector->GetParent())
					name = "Your ship \"" + collector->Name() + "\" picked up ";
				else
					name = "You picked up ";
			}
			string commodity;
			int amount = 0;
			if(it->OutfitType())
			{
				amount = collector->Cargo().Add(it->OutfitType(), it->Count());
				if(!name.empty())
				{
					if(it->OutfitType()->Get("installable") < 0.)
						commodity = it->OutfitType()->Name();
					else
						Messages::Add(name + Format::Number(amount) + " " + it->OutfitType()->Name()
							+ (amount == 1 ? "." : "s."));
				}
			}
			else
			{
				amount = collector->Cargo().Add(it->CommodityType(), it->Count());
				if(!name.empty())
					commodity = it->CommodityType();
					
			}
			if(!commodity.empty())
				Messages::Add(name + (amount == 1 ? "a ton" : Format::Number(amount) + " tons")
					+ " of " + Format::LowerCase(commodity) + ".");
			
			it = flotsam.erase(it);
			continue;
		}
		
		// Draw this flotsam.
		draw[calcTickTock].Add(*it);
		++it;
	}
	
	// Keep track of the relative strength of each government in this system. Do
	// not add more ships to make a winning team even stronger. This is mostly
	// to avoid having the player get mobbed by pirates, say, if they hang out
	// in one system for too long.
	map<const Government *, int64_t> strength;
	// Now, ships fire new projectiles, which includes launching fighters. If an
	// anti-missile system is ready to fire, it does not actually fire unless a
	// missile is detected in range during collision detection, below.
	vector<Ship *> hasAntiMissile;
	double clickRange = 50.;
	const Ship *previousTarget = nullptr;
	const Ship *clickTarget = nullptr;
	if(player.Flagship() && player.Flagship()->GetTargetShip())
		previousTarget = &*player.Flagship()->GetTargetShip();
	
	bool showFlagship = false;
	bool hasHostiles = false;
	for(shared_ptr<Ship> &ship : ships)
		if(ship->GetSystem() == player.GetSystem())
		{
			strength[ship->GetGovernment()] += ship->Cost();
			
			// Note: if a ship "fires" a fighter, that fighter was already in
			// existence and under the control of the same AI as the ship, but
			// its system was null to mark that it was not active.
			ship->Launch(ships);
			if(ship->Fire(projectiles, effects))
				hasAntiMissile.push_back(ship.get());
			
			int scan = ship->Scan();
			if(scan)
			{
				shared_ptr<Ship> target = ship->GetTargetShip();
				if(target && target->IsTargetable())
					eventQueue.emplace_back(ship, target, scan);
			}
			
			// This is a good opportunity to draw all the ships in system.
			if(!ship->HasSprite())
				continue;
			
			// Draw the flagship separately, on top of everything else.
			if(ship.get() != flagship)
			{
				AddSprites(*ship);
				if(ship->IsThrusting())
				{
					for(const auto &it : ship->Attributes().FlareSounds())
						if(it.second > 0)
							Audio::Play(it.first, ship->Position());
				}
			}
			else
				showFlagship = true;
			
			// Do not show cloaked ships on the radar, except the player's ships.
			bool isPlayer = ship->GetGovernment()->IsPlayer();
			if(ship->Cloaking() == 1. && !isPlayer)
				continue;
			
			if(doClick && &*ship != player.Flagship() && ship->IsTargetable())
			{
				Point position = ship->Position() - newCenter;
				const Mask &mask = ship->GetMask(step);
				double range = mask.Range(clickPoint - position, ship->Facing());
				if(range <= clickRange)
				{
					clickRange = range;
					clickTarget = ship.get();
					player.Flagship()->SetTargetShip(ship);
					// If we've found an enemy within the click zone, favor
					// targeting it rather than any other ship. Otherwise, keep
					// checking for hits because another ship might be an enemy.
					if(!range && ship->GetGovernment()->IsEnemy())
						doClick = false;
				}
			}
			
			double size = sqrt(ship->Width() + ship->Height()) * .14 + .5;
			bool isYourTarget = (flagship && ship == flagship->GetTargetShip());
			int type = RadarType(*ship);
			hasHostiles |= (type == Radar::HOSTILE);
			radar[calcTickTock].Add(isYourTarget ? Radar::SPECIAL : type, ship->Position(), size);
		}
	if(flagship && showFlagship)
	{
		AddSprites(*flagship);
		if(flagship->IsThrusting())
		{
			for(const auto &it : flagship->Attributes().FlareSounds())
				if(it.second > 0)
					Audio::Play(it.first);
		}
	}
	if(clickTarget && clickTarget == previousTarget)
		clickCommands |= Command::BOARD;
	if(alarmTime)
		--alarmTime;
	else if(hasHostiles && !hadHostiles)
	{
		if(Preferences::Has("Warning siren"))
			Audio::Play(Audio::Get("alarm"));
		alarmTime = 180;
		hadHostiles = true;
	}
	else if(!hasHostiles)
		hadHostiles = false;
	
	// Collision detection:
	if(grudgeTime)
		--grudgeTime;
	for(Projectile &projectile : projectiles)
	{
		// The asteroids can collide with projectiles, the same as any other
		// object. If the asteroid turns out to be closer than the ship, it
		// shields the ship (unless the projectile has a blast radius).
		Point hitVelocity;
		double closestHit = 0.;
		shared_ptr<Ship> hit;
		const Government *gov = projectile.GetGovernment();
		
		// If this "projectile" is a ship explosion, it always explodes.
		if(gov)
		{
			closestHit = asteroids.Collide(projectile, step, &hitVelocity);
			// Projectiles can only collide with ships that are in the current
			// system and are not landing, and that are hostile to this projectile.
			for(shared_ptr<Ship> &ship : ships)
				if(ship->GetSystem() == player.GetSystem() && !ship->IsLanding() && ship->Cloaking() < 1.)
				{
					if(ship.get() != projectile.Target() && !gov->IsEnemy(ship->GetGovernment()))
						continue;
					
					// This returns a value of 0 if the projectile has a trigger
					// radius and the ship is within it.
					double range = projectile.CheckCollision(*ship, step);
					if(range < closestHit)
					{
						closestHit = range;
						hit = ship;
						hitVelocity = ship->Velocity();
					}
				}
		}
		
		if(closestHit < 1.)
		{
			// Create the explosion the given distance along the projectile's
			// motion path for this step.
			projectile.Explode(effects, closestHit, hitVelocity);
			
			// If this projectile has a blast radius, find all ships within its
			// radius. Otherwise, only one is damaged.
			if(projectile.HasBlastRadius())
			{
				// Even friendly ships can be hit by the blast.
				for(shared_ptr<Ship> &ship : ships)
					if(ship->GetSystem() == player.GetSystem() && ship->Zoom() == 1.)
						if(projectile.InBlastRadius(*ship, step, closestHit))
						{
							int eventType = ship->TakeDamage(projectile, ship != hit);
							if(eventType)
								eventQueue.emplace_back(
									projectile.GetGovernment(), ship, eventType);
						}
			}
			else if(hit)
			{
				int eventType = hit->TakeDamage(projectile);
				if(eventType)
					eventQueue.emplace_back(
						projectile.GetGovernment(), hit, eventType);
			}
			
			if(hit)
				DoGrudge(hit, projectile.GetGovernment());
		}
		else if(projectile.MissileStrength())
		{
			bool isEnemy = projectile.GetGovernment() && projectile.GetGovernment()->IsEnemy();
			radar[calcTickTock].Add(
				isEnemy ? Radar::SPECIAL : Radar::INACTIVE, projectile.Position(), 1.);
			
			// If the projectile did not hit anything, give the anti-missile
			// systems a chance to shoot it down.
			for(Ship *ship : hasAntiMissile)
				if(ship == projectile.Target()
						|| gov->IsEnemy(ship->GetGovernment())
						|| ship->GetGovernment()->IsEnemy(gov))
					if(ship->FireAntiMissile(projectile, effects))
					{
						projectile.Kill();
						break;
					}
		}
		else if(projectile.HasBlastRadius())
			radar[calcTickTock].Add(Radar::SPECIAL, projectile.Position(), 1.8);
		
		// Now, we can draw the projectile. The motion blur should be reduced
		// depending on how much motion blur is in the sprite itself:
		double innateVelocity = 2. * projectile.GetWeapon().Velocity();
		Point relativeVelocity = projectile.Velocity() - projectile.Unit() * innateVelocity;
		draw[calcTickTock].AddProjectile(projectile, relativeVelocity, closestHit);
	}
	
	// Finally, draw all the effects, and then move them (because their motion
	// is not dependent on anything else, and this way we do all the work on
	// them in a single place.
	for(auto it = effects.begin(); it != effects.end(); )
	{
		draw[calcTickTock].AddUnblurred(*it);
		
		if(!it->Move())
			it = effects.erase(it);
		else
			++it;
	}
	
	// Add incoming ships.
	for(const System::FleetProbability &fleet : player.GetSystem()->Fleets())
		if(!Random::Int(fleet.Period()))
		{
			const Government *gov = fleet.Get()->GetGovernment();
			if(!gov)
				continue;
			
			int64_t enemyStrength = 0;
			for(const auto &it : strength)
				if(gov->IsEnemy(it.first))
					enemyStrength += it.second;
			if(enemyStrength && strength[gov] > 2 * enemyStrength)
				continue;
			
			fleet.Get()->Enter(*player.GetSystem(), ships);
		}
	if(!Random::Int(36000) && !player.GetSystem()->Links().empty())
	{
		// Loop through all persons once to see if there are any who can enter
		// this system.
		int sum = 0;
		for(const auto &it : GameData::Persons())
			sum += it.second.Frequency(player.GetSystem());
		
		if(sum)
		{
			// Adjustment factor: special persons will appear once every ten
			// minutes, but much less frequently if the game only specifies a
			// few of them. This way, they will become more common as I add
			// more, without needing to change the 10-minute constant above.
			sum = Random::Int(sum + 1000);
			for(const auto &it : GameData::Persons())
			{
				const Person &person = it.second;
				sum -= person.Frequency(player.GetSystem());
				if(sum < 0)
				{
					shared_ptr<Ship> ship = person.GetShip();
					ship->Recharge();
					ship->SetName(it.first);
					ship->SetGovernment(person.GetGovernment());
					ship->SetPersonality(person.GetPersonality());
					ship->SetHail(person.GetHail());
					Fleet::Enter(*player.GetSystem(), *ship);
					
					ships.push_front(ship);
					
					break;
				}
			}
		}
	}
	
	// Occasionally have some ship hail you.
	if(!Random::Int(600) && !ships.empty())
	{
		shared_ptr<Ship> source;
		unsigned i = Random::Int(ships.size());
		for(const shared_ptr<Ship> &it : ships)
			if(!i--)
			{
				source = it;
				break;
			}
		if(source->GetGovernment() && !source->GetGovernment()->IsPlayer()
				&& !source->IsDisabled() && source->Crew())
		{
			string message = source->GetHail();
			if(!message.empty() && source->GetSystem() == player.GetSystem())
				Messages::Add(source->GetGovernment()->GetName() + " ship \""
					+ source->Name() + "\": " + message);
		}
	}
	
	// A mouse click should only be active for a single step.
	doClick = false;
	
	// Keep track of how much of the CPU time we are using.
	loadSum += loadTimer.Time();
	if(++loadCount == 60)
	{
		load = loadSum;
		loadSum = 0.;
		loadCount = 0;
	}
}