Feature: setting for more flexible town spacing

src/core/math_func.hpp

@@ -365,4 +365,18 @@ static inline int DivAwayFromZero(int a, uint b)
 
 uint32 IntSqrt(uint32 num);
 
+/**
+ * Computes the smallest nonnegative number r with a = q*b + r.
+ * (remainder of integer division with rounding towards -infinity)
+ * We can't rely on % giving sane results for negative a.
+ * @param a Numerator
+ * @param b Denominator
+ * @return Remainder
+ */
+static inline uint Mod(int a, uint b)
+{
+	if (a >= 0) return ((uint)a)%b;
+	return b-(((uint)(-a-1))%b)-1;
+}
+
 #endif /* MATH_FUNC_HPP */

src/genworld.cpp

@@ -137,7 +137,7 @@ static void _GenerateWorld()
 
 			/* only generate towns, tree and industries in newgame mode. */
 			if (_game_mode != GM_EDITOR) {
-				if (!GenerateTowns(_settings_game.economy.town_layout)) {
+				if (!GenerateTowns(_settings_game.economy.town_layout, TS_RANDOM)) {
 					_cur_company.Restore();
 					HandleGeneratingWorldAbortion();
 					return;

src/lang/english.txt

@@ -1580,11 +1580,11 @@ STR_CONFIG_SETTING_CYCLE_SIGNAL_ALL                             :All
 
 STR_CONFIG_SETTING_TOWN_LAYOUT                                  :Road layout for new towns: {STRING2}
 STR_CONFIG_SETTING_TOWN_LAYOUT_HELPTEXT                         :Layout for the road network of towns
-STR_CONFIG_SETTING_TOWN_LAYOUT_DEFAULT                          :Original
-STR_CONFIG_SETTING_TOWN_LAYOUT_BETTER_ROADS                     :Better roads
-STR_CONFIG_SETTING_TOWN_LAYOUT_2X2_GRID                         :2x2 grid
-STR_CONFIG_SETTING_TOWN_LAYOUT_3X3_GRID                         :3x3 grid
+STR_CONFIG_SETTING_TOWN_LAYOUT_DEFAULT                          :natural
+STR_CONFIG_SETTING_TOWN_LAYOUT_GRID                             :grid
 STR_CONFIG_SETTING_TOWN_LAYOUT_RANDOM                           :Random
+STR_CONFIG_SETTING_MIN_TOWN_SPACING                             :Smallest minimum distance beetween parallel roads: {STRING2}
+STR_CONFIG_SETTING_MAX_TOWN_SPACING                             :Largest minimum distance beetween parallel roads: {STRING2}
 STR_CONFIG_SETTING_ALLOW_TOWN_ROADS                             :Towns are allowed to build roads: {STRING2}
 STR_CONFIG_SETTING_ALLOW_TOWN_ROADS_HELPTEXT                    :Allow towns to build roads for growth. Disable to prevent town authorities from building roads themselves
 STR_CONFIG_SETTING_ALLOW_TOWN_LEVEL_CROSSINGS                   :Towns are allowed to build level crossings: {STRING2}

src/saveload/afterload.cpp

@@ -2155,7 +2155,7 @@ bool AfterLoadGame()
 		/* allow_town_roads is added, set it if town_layout wasn't TL_NO_ROADS */
 		if (_settings_game.economy.town_layout == 0) { // was TL_NO_ROADS
 			_settings_game.economy.allow_town_roads = false;
-			_settings_game.economy.town_layout = TL_BETTER_ROADS;
+			_settings_game.economy.town_layout = TL_NATURAL;
 		} else {
 			_settings_game.economy.allow_town_roads = true;
 			_settings_game.economy.town_layout = static_cast<TownLayout>(_settings_game.economy.town_layout - 1);
@@ -3207,6 +3207,32 @@ bool AfterLoadGame()
 		FOR_ALL_STATIONS(st) UpdateStationAcceptance(st, false);
 	}
 
+	if (IsSavegameVersionBefore(SLV_TOWN_SPACING)) {
+		/* Town spacing parameter has been added */
+		Town *t;
+		FOR_ALL_TOWNS(t) {
+			switch (t->layout) {
+				default: NOT_REACHED();
+				case 0: /* TL_ORIGINAL */
+					t->layout = TL_NATURAL;
+					t->spacing = 1;
+					break;
+				case 1: /* TL_BETTER_ROADS */
+					t->layout = TL_NATURAL;
+					t->spacing = 2;
+					break;
+				case 2: /* TL_2x2_GRID */
+					t->layout = TL_GRID;
+					t->spacing = 2;
+					break;
+				case 3: /* TL_3x3_GRID */
+					t->layout = TL_GRID;
+					t->spacing = 3;
+					break;
+			}
+		}
+	}
+
 	/* Road stops is 'only' updating some caches */
 	AfterLoadRoadStops();
 	AfterLoadLabelMaps();

src/saveload/saveload.h

@@ -303,6 +303,8 @@ enum SaveLoadVersion : uint16 {
 	SLV_SCRIPT_MEMLIMIT,                    ///< 215  PR#7516 Limit on AI/GS memory consumption.
 	SLV_MULTITILE_DOCKS,                    ///< 216  PR#7380 Multiple docks per station.
 
+	SLV_TOWN_SPACING,
+
 	SL_MAX_VERSION,                         ///< Highest possible saveload version
 };
 

src/script/api/ai/ai_town.hpp.sq

@@ -39,10 +39,8 @@ void SQAITown_Register(Squirrel *engine)
 	SQAITown.DefSQConst(engine, ScriptTown::TOWN_RATING_EXCELLENT,        "TOWN_RATING_EXCELLENT");
 	SQAITown.DefSQConst(engine, ScriptTown::TOWN_RATING_OUTSTANDING,      "TOWN_RATING_OUTSTANDING");
 	SQAITown.DefSQConst(engine, ScriptTown::TOWN_RATING_INVALID,          "TOWN_RATING_INVALID");
-	SQAITown.DefSQConst(engine, ScriptTown::ROAD_LAYOUT_ORIGINAL,         "ROAD_LAYOUT_ORIGINAL");
-	SQAITown.DefSQConst(engine, ScriptTown::ROAD_LAYOUT_BETTER_ROADS,     "ROAD_LAYOUT_BETTER_ROADS");
-	SQAITown.DefSQConst(engine, ScriptTown::ROAD_LAYOUT_2x2,              "ROAD_LAYOUT_2x2");
-	SQAITown.DefSQConst(engine, ScriptTown::ROAD_LAYOUT_3x3,              "ROAD_LAYOUT_3x3");
+	SQAITown.DefSQConst(engine, ScriptTown::ROAD_LAYOUT_NATURAL,          "ROAD_LAYOUT_NATURAL");
+	SQAITown.DefSQConst(engine, ScriptTown::ROAD_LAYOUT_GRID,             "ROAD_LAYOUT_GRID");
 	SQAITown.DefSQConst(engine, ScriptTown::ROAD_LAYOUT_INVALID,          "ROAD_LAYOUT_INVALID");
 	SQAITown.DefSQConst(engine, ScriptTown::TOWN_SIZE_SMALL,              "TOWN_SIZE_SMALL");
 	SQAITown.DefSQConst(engine, ScriptTown::TOWN_SIZE_MEDIUM,             "TOWN_SIZE_MEDIUM");

src/script/api/game/game_town.hpp.sq

@@ -39,10 +39,8 @@ void SQGSTown_Register(Squirrel *engine)
 	SQGSTown.DefSQConst(engine, ScriptTown::TOWN_RATING_EXCELLENT,        "TOWN_RATING_EXCELLENT");
 	SQGSTown.DefSQConst(engine, ScriptTown::TOWN_RATING_OUTSTANDING,      "TOWN_RATING_OUTSTANDING");
 	SQGSTown.DefSQConst(engine, ScriptTown::TOWN_RATING_INVALID,          "TOWN_RATING_INVALID");
-	SQGSTown.DefSQConst(engine, ScriptTown::ROAD_LAYOUT_ORIGINAL,         "ROAD_LAYOUT_ORIGINAL");
-	SQGSTown.DefSQConst(engine, ScriptTown::ROAD_LAYOUT_BETTER_ROADS,     "ROAD_LAYOUT_BETTER_ROADS");
-	SQGSTown.DefSQConst(engine, ScriptTown::ROAD_LAYOUT_2x2,              "ROAD_LAYOUT_2x2");
-	SQGSTown.DefSQConst(engine, ScriptTown::ROAD_LAYOUT_3x3,              "ROAD_LAYOUT_3x3");
+	SQGSTown.DefSQConst(engine, ScriptTown::ROAD_LAYOUT_NATURAL,          "ROAD_LAYOUT_NATURAL");
+	SQGSTown.DefSQConst(engine, ScriptTown::ROAD_LAYOUT_GRID,             "ROAD_LAYOUT_GRID");
 	SQGSTown.DefSQConst(engine, ScriptTown::ROAD_LAYOUT_INVALID,          "ROAD_LAYOUT_INVALID");
 	SQGSTown.DefSQConst(engine, ScriptTown::TOWN_SIZE_SMALL,              "TOWN_SIZE_SMALL");
 	SQGSTown.DefSQConst(engine, ScriptTown::TOWN_SIZE_MEDIUM,             "TOWN_SIZE_MEDIUM");

src/script/api/script_town.cpp

@@ -287,7 +287,7 @@
 	EnforcePrecondition(false, size == TOWN_SIZE_SMALL || size == TOWN_SIZE_MEDIUM || size == TOWN_SIZE_LARGE)
 	EnforcePrecondition(false, size != TOWN_SIZE_LARGE || ScriptObject::GetCompany() == OWNER_DEITY);
 	if (ScriptObject::GetCompany() == OWNER_DEITY || _settings_game.economy.found_town == TF_CUSTOM_LAYOUT) {
-		EnforcePrecondition(false, layout == ROAD_LAYOUT_ORIGINAL || layout == ROAD_LAYOUT_BETTER_ROADS || layout == ROAD_LAYOUT_2x2 || layout == ROAD_LAYOUT_3x3);
+		EnforcePrecondition(false, layout == ROAD_LAYOUT_NATURAL || layout == ROAD_LAYOUT_GRID);
 	} else {
 		/* The layout parameter is ignored for AIs when custom layouts is disabled. */
 		layout = (RoadLayout) (byte)_settings_game.economy.town_layout;

src/script/api/script_town.hpp

@@ -96,10 +96,8 @@ class ScriptTown : public ScriptObject {
 	 */
 	enum RoadLayout {
 		/* Note: these values represent part of the in-game TownLayout enum */
-		ROAD_LAYOUT_ORIGINAL      = ::TL_ORIGINAL,     ///< Original algorithm (min. 1 distance between roads).
-		ROAD_LAYOUT_BETTER_ROADS  = ::TL_BETTER_ROADS, ///< Extended original algorithm (min. 2 distance between roads).
-		ROAD_LAYOUT_2x2           = ::TL_2X2_GRID,     ///< Geometric 2x2 grid algorithm
-		ROAD_LAYOUT_3x3           = ::TL_3X3_GRID,     ///< Geometric 3x3 grid algorithm
+		ROAD_LAYOUT_NATURAL       = ::TL_NATURAL,     ///TODO: compatibility
+		ROAD_LAYOUT_GRID          = ::TL_GRID,
 
 		/* Custom added value, only valid for this API */
 		ROAD_LAYOUT_INVALID       = -1,                ///< The layout for invalid towns.

src/settings_gui.cpp

@@ -1698,6 +1698,8 @@ static SettingsContainer &GetSettingsTree()
 			genworld->Add(new SettingEntry("economy.larger_towns"));
 			genworld->Add(new SettingEntry("economy.initial_city_size"));
 			genworld->Add(new SettingEntry("economy.town_layout"));
+			genworld->Add(new SettingEntry("economy.town_min_spacing"));
+			genworld->Add(new SettingEntry("economy.town_max_spacing"));
 			genworld->Add(new SettingEntry("difficulty.industry_density"));
 			genworld->Add(new SettingEntry("gui.pause_on_newgame"));
 		}

src/settings_type.h

@@ -484,6 +484,8 @@ struct EconomySettings {
 	uint8  larger_towns;                     ///< the number of cities to build. These start off larger and grow twice as fast
 	uint8  initial_city_size;                ///< multiplier for the initial size of the cities compared to towns
 	TownLayout town_layout;                  ///< select town layout, @see TownLayout
+	TownSpacing town_min_spacing;            ///< smallest minimal distance between parallel roads for towns
+	TownSpacing town_max_spacing;            ///< largest minimal distance between parallel roads for towns
 	TownCargoGenMode town_cargogen_mode;     ///< algorithm for generating cargo from houses, @see TownCargoGenMode
 	bool   allow_town_roads;                 ///< towns are allowed to build roads (always allowed when generating world / in SE)
 	TownFounding found_town;                 ///< town founding.

src/table/settings.ini

@@ -574,7 +574,7 @@ var      = economy.town_layout
 type     = SLE_UINT8
 from     = SLV_59
 guiflags = SGF_MULTISTRING
-def      = TL_ORIGINAL
+def      = TL_NATURAL
 min      = TL_BEGIN
 max      = NUM_TLS - 1
 interval = 1
@@ -583,6 +583,31 @@ strhelp  = STR_CONFIG_SETTING_TOWN_LAYOUT_HELPTEXT
 strval   = STR_CONFIG_SETTING_TOWN_LAYOUT_DEFAULT
 proc     = TownFoundingChanged
 
+[SDT_VAR]
+base     = GameSettings
+var      = economy.town_min_spacing
+type     = SLE_UINT8
+from     = SLV_TOWN_SPACING
+def      = 2
+min      = 1
+max      = MAX_TOWN_SPACING
+interval = 1
+str      = STR_CONFIG_SETTING_MIN_TOWN_SPACING
+strval   = STR_JUST_COMMA
+
+[SDT_VAR]
+base     = GameSettings
+var      = economy.town_max_spacing
+type     = SLE_UINT8
+from     = SLV_TOWN_SPACING
+def      = 2
+min      = 1
+max      = MAX_TOWN_SPACING
+interval = 1
+str      = STR_CONFIG_SETTING_MAX_TOWN_SPACING
+strval   = STR_JUST_COMMA
+#proc = check max >= min
+
 [SDT_BOOL]
 base     = GameSettings
 var      = economy.allow_town_roads

src/town.h

@@ -100,6 +100,7 @@ struct Town : TownPool::PoolItem<&_town_pool> {
 
 	bool larger_town;                ///< if this is a larger town and should grow more quickly
 	TownLayout layout;               ///< town specific road layout
+	TownSpacing spacing;             ///< minimum distance between parallel roads
 
 	bool show_zone;                  ///< NOSAVE: mark town to show the local authority zone in the viewports
 
@@ -114,7 +115,7 @@ struct Town : TownPool::PoolItem<&_town_pool> {
 	/** Destroy the town. */
 	~Town();
 
-	void InitializeLayout(TownLayout layout);
+	void InitializeLayout(TownLayout layout, TownSpacing spacing);
 
 	/**
 	 * Calculate the max town noise.
@@ -204,7 +205,7 @@ void ChangeTownRating(Town *t, int add, int max, DoCommandFlag flags);
 HouseZonesBits GetTownRadiusGroup(const Town *t, TileIndex tile);
 void SetTownRatingTestMode(bool mode);
 uint GetMaskOfTownActions(int *nump, CompanyID cid, const Town *t);
-bool GenerateTowns(TownLayout layout);
+bool GenerateTowns(TownLayout layout, TownSpacing spacing);
 const CargoSpec *FindFirstCargoWithTownEffect(TownEffect effect);
 
 /** Town actions of a company. */