Forward-port suokko's improvements to AI recruitment,

...previously reverted as an emergency fix, from 2008-09-16T18:14:54Z!paniemin@cc.hut.fi and
2008-09-16T19:26:36Z!paniemin@cc.hut.fi.

src/ai.cpp

@@ -175,18 +175,20 @@ protected:
 		}
 	}
 
-	void do_recruitment() {
+	bool do_recruitment() {
 		const std::set<std::string>& options = current_team().recruits();
-	if (!options.empty()) {
+		if (!options.empty()) {
 			const int choice = (rand()%options.size());
 		        std::set<std::string>::const_iterator i = options.begin();
 		        std::advance(i,choice);
 
 			const bool res = recruit(*i);
 			if(res) {
-				do_recruitment();
+				return do_recruitment();
 			}
+			return true;
 		}
+		return false;
 	}
 };
 
@@ -296,7 +298,7 @@ ai::ai(ai_interface::info& info) :
 	avoid_(),
 	unit_stats_cache_(),
 	attack_depth_(0),
-	recruiting_prefered_(false)
+	recruiting_preferred_(0)
 {}
 
 void ai::new_turn()
@@ -971,10 +973,31 @@ void ai::play_turn()
 
 void ai::evaluate_recruiting_value(unit_map::iterator leader)
 {
-	const int gold = current_team().gold();
-//	const int unit_price = current_team().average_recruit_price();
-//	recruiting_prefered_ = (gold/unit_price) > min_recruiting_value_to_force_recruit && !map_.is_keep();
-	recruiting_prefered_ = gold > min_recruiting_value_to_force_recruit && !map_.is_keep(leader->first);
+	if (recruiting_preferred_ == 2)
+	{
+		recruiting_preferred_ = 0;
+		return;
+	}
+	if (current_team().num_pos_recruits_to_force()< 0.01f)
+	{
+		return;
+	}
+
+	float free_slots = 0.0f;
+	if (map_.is_keep(leader->first))
+	{
+		std::set<location> checked_hexes;
+		checked_hexes.insert(leader->first);
+		free_slots = count_free_hexes_in_castle(leader->first, checked_hexes);
+	}
+	const float gold = current_team().gold();
+	const float unit_price = current_team().average_recruit_price();
+	recruiting_preferred_ = (gold/unit_price) - free_slots > current_team().num_pos_recruits_to_force();
+	DBG_AI << "recruiting preferred: " << (recruiting_preferred_?"yes":"no") << 
+		" units to recruit: " << (gold/unit_price) << 
+		" unit_price: " << unit_price <<
+		" free slots: " << free_slots <<
+		" limit: " << current_team().num_pos_recruits_to_force() << "\n";
 }
 
 void ai::do_move()
@@ -1157,7 +1180,7 @@ bool ai::do_combat(std::map<map_location,paths>& possible_moves, const move_map&
 		LOG_AI << "attack option rated at " << rating << " ("
 			<< current_team().aggression() << ")\n";
 
-		if (recruiting_prefered_)
+		if (recruiting_preferred_)
 		{
 			unit_map::unit_iterator u = units_.find(it->movements[0].first);
 			if (u != units_.end()
@@ -1814,11 +1837,11 @@ void ai::analyze_potential_recruit_movements()
 	}
 }
 
-void ai::do_recruitment()
+bool ai::do_recruitment()
 {
 	const unit_map::const_iterator leader = find_leader(units_,team_num_);
 	if(leader == units_.end()) {
-		return;
+		return false;
 	}
 
 	const location& start_pos = nearest_keep(leader->first);
@@ -1892,12 +1915,16 @@ void ai::do_recruitment()
 		options.push_back("");
 	}
 	// Buy units as long as we have room and can afford it.
+        bool ret = false;
 	while (recruit_usage(options[rand()%options.size()])) {
+		ret = true;
 		options = current_team().recruitment_pattern();
 		if (options.empty()) {
 			options.push_back("");
 		}
 	}
+
+	return ret;
 }
 
 void ai::move_leader_to_goals( const move_map& enemy_dstsrc)

src/ai.hpp

@@ -91,7 +91,7 @@ protected:
 			const unit_map::const_iterator un, const move_map& srcdst,
 			const move_map& dstsrc, const move_map& enemy_dstsrc, double caution);
 
-	virtual void do_recruitment();
+	virtual bool do_recruitment();
 
 	virtual void move_leader_to_keep(const move_map& enemy_dstsrc);
 	virtual void move_leader_after_recruit(const move_map& srcdst,
@@ -377,7 +377,7 @@ private:
 		const std::map<map_location,paths>& possible_moves,
 		const std::multimap<map_location,map_location>& enemy_dstsrc) const;
 	
-	bool recruiting_prefered_;
+	int recruiting_preferred_;
 	static const int min_recruiting_value_to_force_recruit = 28;
 };
 

src/ai_move.cpp

@@ -853,7 +853,7 @@ void ai::move_leader_to_keep(const move_map& enemy_dstsrc)
 					:0);
 				const int enemy = (power_projection(*i, enemy_dstsrc) * 8 * leader->second.total_movement())/leader->second.hitpoints();
 				int multiturn_move_penalty = 0;
-				if (recruiting_prefered_)
+				if (recruiting_preferred_)
 					multiturn_move_penalty = 2;
 
 				const int distance_value = (distance > leader->second.movement_left()? 

src/ai_village.cpp

@@ -262,7 +262,7 @@ void ai::find_villages(
 {
 	std::map<location, double> vulnerability;
 
-	const bool passive_leader = recruiting_prefered_ ||  
+	const bool passive_leader = recruiting_preferred_ ||  
 		utils::string_bool(current_team().ai_parameters()["passive_leader"]);
 
 	size_t min_distance = 100000;

src/formula_ai.cpp

@@ -1771,10 +1771,10 @@ bool formula_ai::execute_variant(const variant& var, bool commandline)
 }
 
 
-void formula_ai::do_recruitment()
+bool formula_ai::do_recruitment()
 {
 	if(!recruit_formula_) {
-		return;
+		return false;
 	}
 
 	variant var = recruit_formula_->execute(*this);
@@ -1787,17 +1787,19 @@ void formula_ai::do_recruitment()
 		vars.push_back(var);
 	}
 
+	bool ret = false;
 	for(std::vector<variant>::const_iterator i = vars.begin(); i != vars.end(); ++i) {
 		if(!i->is_string()) {
-			return;
+			return false;
 		}
 
 		if(!recruit(i->as_string())) {
-			return;
+			return ret;
 		}
+		ret = true;
 	}
 
-	do_recruitment();
+	return do_recruitment();
 }
 
 namespace {

src/formula_ai.hpp

@@ -153,7 +153,7 @@ private:
 	void handle_exception(game_logic::formula_error& e);
 	void handle_exception(game_logic::formula_error& e, const std::string& failed_operation);
 	void display_message(const std::string& msg);
-	void do_recruitment();
+	bool do_recruitment();
 	bool make_move(game_logic::const_formula_ptr formula_, const game_logic::formula_callable& variables);
 	bool execute_variant(const variant& var, bool commandline=false);
 	virtual variant get_value(const std::string& key) const;