refactor town entrance search into cScenario function

src/game/boe.main.cpp

@@ -440,33 +440,28 @@ static void handle_scenario_args() {
 		}
 		// Try to put the party in an outdoor section from which you can enter the town --
 		// so when you leave, you'll hopefully be in the right place.
-		bool found_entrance = false;
-		for(int x = 0; x < univ.scenario.outdoors.width(); ++x){
-			for(int y = 0; y < univ.scenario.outdoors.height(); ++y){
-				for(spec_loc_t& entrance : univ.scenario.outdoors[x][y]->city_locs){
-					if(entrance.spec == *scen_arg_town){
-						// Very janky but I don't know how else to make it properly load the right sections and set i_w_c
-						while(univ.party.outdoor_corner.x > x){
-							shift_universe_left();
-						}
-						while(univ.party.outdoor_corner.x < x){
-							shift_universe_right();
-						}
-						while(univ.party.outdoor_corner.y > y){
-							shift_universe_up();
-						}
-						while(univ.party.outdoor_corner.y < y){
-							shift_universe_down();
-						}
-						outd_move_party(local_to_global(entrance), true);
-
-						found_entrance = true;
-						break;
-					}
-				}
-				if(found_entrance) break;
+		auto town_entrances = univ.scenario.find_town_entrances(*scen_arg_town);
+		if(!town_entrances.empty()){
+			// TODO a dialog could be shown to choose between multiple entrances,
+			// but maybe that would be janky, because this happens when you're trying to launch
+			// from INSIDE a town.
+			town_entrance_t first_entrance_found = town_entrances[0];
+			int x = first_entrance_found.out_sec.x;
+			int y = first_entrance_found.out_sec.y;
+			// Very janky but I don't know how else to make it properly load the right sections and set i_w_c
+			while(univ.party.outdoor_corner.x > x){
+				shift_universe_left();
 			}
-			if(found_entrance) break;
+			while(univ.party.outdoor_corner.x < x){
+				shift_universe_right();
+			}
+			while(univ.party.outdoor_corner.y > y){
+				shift_universe_up();
+			}
+			while(univ.party.outdoor_corner.y < y){
+				shift_universe_down();
+			}
+			outd_move_party(local_to_global(first_entrance_found.loc), true);
 		}
 
 		short town_entrance = 0;

src/scenario/scenario.cpp

@@ -577,3 +577,17 @@ void cScenario::readFrom(const cTagFile& file){
 		}
 	}
 }
+
+std::vector<town_entrance_t> cScenario::find_town_entrances(int town_num) {
+	std::vector<town_entrance_t> matching_entrances;
+	for(int x = 0; x < outdoors.width(); ++x){
+		for(int y = 0; y < outdoors.height(); ++y){
+			for(spec_loc_t& entrance : outdoors[x][y]->city_locs){
+				if(town_num == -1 || entrance.spec == town_num){
+					matching_entrances.push_back({{x, y}, {entrance.x, entrance.y}, static_cast<int>(entrance.spec)});
+				}
+			}
+		}
+	}
+	return matching_entrances;
+}

src/scenario/scenario.hpp

@@ -39,6 +39,13 @@ struct scenario_header_flags {
 
 enum eContentRating {G, PG, R, NC17};
 
+// Used for finding town entrances in the outdoors
+struct town_entrance_t {
+	location out_sec;
+	location loc;
+	int town;
+};
+
 class cScenario {
 public:
 	class cItemStorage {
@@ -117,6 +124,10 @@ public:
 	cItem return_treasure(int loot, bool allow_junk_treasure = false) const;
 	cItem pull_item_of_type(unsigned int loot_max,short min_val,short max_val,const std::vector<eItemType>& types,bool allow_junk_treasure=false) const;
 	
+	// Debugging/Editing helper: find town entrances in the outdoors. When town_num is specified, only return entrances
+	// to the town with that number
+	std::vector<town_entrance_t> find_town_entrances(int town_num = -1);
+
 	void reset_version();
 	explicit cScenario();
 	~cScenario();