made AI know the basics of backstab

data/translations/english.cfg

@@ -383,6 +383,8 @@ message="Message"
 describe_unit="Describe Unit"
 rename_unit="Rename Unit"
 scenario_objectives="Scenario Objectives"
+mp_objectives="Victory
+@Defeat enemy leader(s)"
 recruit="Recruit"
 recall="Recall"
 recall_disallowed="You are seperated from your soldiers and may not recall them"

src/ai_attack.cpp

@@ -73,6 +73,17 @@ void ai::do_attack_analysis(
 		const unit_map::const_iterator unit_itor = units_.find(current_unit);
 		assert(unit_itor != units_.end());
 
+		//see if the unit has the backstab ability -- units with backstab
+		//will want to try to have a friendly unit opposite the position they move to
+		bool backstab = false;
+		const std::vector<attack_type>& attacks = unit_itor->second.attacks();
+		for(std::vector<attack_type>::const_iterator a = attacks.begin(); a != attacks.end(); ++a) {
+			if(a->backstab()) {
+				backstab = true;
+				break;
+			}
+		}
+
 		double best_vulnerability = 0.0, best_support = 0.0;
 		int best_rating = 0;
 		int cur_position = -1;
@@ -99,8 +110,24 @@ void ai::do_attack_analysis(
 				continue;
 			}
 
+			//check to see whether this move would be a backstab
+			int backstab_bonus = 1;
+
+			if(backstab && tiles[(j+3)%6] != current_unit) {
+				const unit_map::const_iterator itor = units_.find(tiles[(j+3)%6]);
+
+				//note that we *could* also check if a unit plans to move there before we're
+				//at this stage, but we don't because, since the attack calculations don't
+				//actually take backstab into account (too complicated), this could actually
+				//make our analysis look *worse* instead of better.
+				//so we only check for 'concrete' backstab opportunities.
+				if(itor != units_.end() && itor->second.side() == unit_itor->second.side()) {
+					backstab_bonus = 2;
+				}
+			}
+
 			//see if this position is the best rated we've seen so far
-			const int rating = rate_terrain(unit_itor->second,tiles[j]);
+			const int rating = rate_terrain(unit_itor->second,tiles[j]) * backstab_bonus;
 			if(cur_position >= 0 && rating < best_rating) {
 				continue;
 			}

src/game_events.cpp

@@ -732,8 +732,8 @@ bool event_handler::handle_event_command(const queued_event& event_info, const s
 		const int size = lexical_cast_default<int>(cfg["size"],12);
 		const int lifetime = lexical_cast_default<int>(cfg["duration"],20);
 		const int red = lexical_cast_default<int>(cfg["red"],0);
-		const int green = lexical_cast_default<int>(cfg["red"],0);
-		const int blue = lexical_cast_default<int>(cfg["red"],0);
+		const int green = lexical_cast_default<int>(cfg["green"],0);
+		const int blue = lexical_cast_default<int>(cfg["blue"],0);
 
 		SDL_Color colour = {red,green,blue,255};
 

src/multiplayer.cpp

@@ -72,7 +72,7 @@ int play_multiplayer(display& disp, game_data& units_data, const config& cfg,
 	int cur_xpmod = 100;
 
 	// Dialog width and height
-	int width = 640;
+	int width = 740;
 	int height = 440;
 	const int left = (disp.x()-width)/2;
 	const int top = (disp.y()-height)/2;

src/multiplayer_connect.cpp

@@ -239,7 +239,7 @@ int mp_connect::load_map(const std::string& era, int map, int num_turns, int vil
 
 	if ((*level_)["objectives"] == "")
 	{
-		(*level_)["objectives"] = "Victory:\n@Defeat enemy leader(s)\n";
+		(*level_)["objectives"] = string_table["mp_objectives"];
 	}
 
 	(*level_)["experience_modifier"] = lexical_cast<std::string>(xpmodifier);

src/replay.cpp

@@ -623,6 +623,12 @@ bool do_replay(display& disp, const gamemap& map, const game_data& gameinfo,
 				throw replay::error();
 			}
 
+			if(u_type->second.cost() > current_team.gold()) {
+				std::cerr << "unit '" << u_type->second.name() << "' is too expensive to recruit: "
+				          << u_type->second.cost() << "/" << current_team.gold() << "\n";
+				throw replay::error();
+			}
+
 			statistics::recruit_unit(new_unit);
 
 			current_team.spend_gold(u_type->second.cost());

src/unit_types.cpp

@@ -33,6 +33,7 @@ attack_type::attack_type(const config& cfg)
 	name_ = cfg["name"];
 	type_ = cfg["type"];
 	special_ = cfg["special"];
+	backstab_ = special_ == "backstab";
 	icon_ = cfg["icon"];
 	if(icon_.empty())
 		icon_ = "misc/" + name_ + ".png";
@@ -139,6 +140,11 @@ double attack_type::defense_weight() const
 	return defense_weight_;
 }
 
+bool attack_type::backstab() const
+{
+	return backstab_;
+}
+
 int attack_type::get_first_frame(attack_type::FRAME_TYPE type) const
 {
 	if(frames_[type].empty())

src/unit_types.hpp

@@ -40,6 +40,8 @@ public:
 	double attack_weight() const;
 	double defense_weight() const;
 
+	bool backstab() const;
+
 	enum FRAME_TYPE { UNIT_FRAME, MISSILE_FRAME };
 	enum FRAME_DIRECTION { VERTICAL, DIAGONAL };
 
@@ -74,6 +76,10 @@ private:
 	double attack_weight_;
 	double defense_weight_;
 
+	//caches whether the unit can backstab. This is important
+	//because the AI queries it alot.
+	bool backstab_;
+
 	struct frame {
 		frame(int i1, int i2, const std::string& img, int offset)
 		      : start(i1), end(i2), xoffset(offset), image(img)