Rescale town cargo adj setting by 10x, for finer adjustment.

Use DECIMAL1 instead of an integer.

src/lang/english.txt

@@ -1666,6 +1666,7 @@ STR_CONFIG_SETTING_TOWN_FOUNDING_FORBIDDEN                      :Forbidden
 STR_CONFIG_SETTING_TOWN_FOUNDING_ALLOWED                        :Allowed
 STR_CONFIG_SETTING_TOWN_FOUNDING_ALLOWED_CUSTOM_LAYOUT          :Allowed, custom town layout
 STR_CONFIG_SETTING_TOWN_CARGO_FACTOR                            :Town cargo generation factor (less < 0 < more): {STRING2}
+STR_CONFIG_SETTING_TOWN_CARGO_FACTOR_HELPTEXT                   :Passenger, mail, and other town cargo production is scaled by approximately 2^factor (exponential)
 
 STR_CONFIG_SETTING_EXTRA_TREE_PLACEMENT                         :In game placement of trees: {STRING2}
 STR_CONFIG_SETTING_EXTRA_TREE_PLACEMENT_HELPTEXT                :Control random appearance of trees during the game. This might affect industries which rely on tree growth, for example lumber mills

src/saveload/afterload.cpp

@@ -3307,6 +3307,11 @@ bool AfterLoadGame()
 		FOR_ALL_VEHICLES(v) SB(v->vehicle_flags, VF_TIMETABLE_SEPARATION, 1, _settings_game.order.old_timetable_separation);
 	}
 
+	/* Set lifetime vehicle profit to 0 if lifetime profit feature is missing */
+	if (!SlXvIsFeaturePresent(XSLFI_TOWN_CARGO_ADJ, 2)) {
+		_settings_game.economy.town_cargo_scale_factor = _settings_game.economy.old_town_cargo_factor * 10;
+	}
+
 	/* Road stops is 'only' updating some caches */
 	AfterLoadRoadStops();
 	AfterLoadLabelMaps();

src/saveload/extended_ver_sl.cpp

@@ -53,7 +53,7 @@ const SlxiSubChunkInfo _sl_xv_sub_chunk_infos[] = {
 	{ XSLFI_ADJACENT_CROSSINGS,     XSCF_NULL,                1,   1, "adjacent_crossings",        NULL, NULL, NULL        },
 	{ XSLFI_DEPARTURE_BOARDS,       XSCF_IGNORABLE_UNKNOWN,   1,   1, "departure_boards",          NULL, NULL, NULL        },
 	{ XSLFI_TIMETABLES_START_TICKS, XSCF_NULL,                2,   2, "timetable_start_ticks",     NULL, NULL, NULL        },
-	{ XSLFI_TOWN_CARGO_ADJ,         XSCF_IGNORABLE_UNKNOWN,   1,   1, "town_cargo_adj",            NULL, NULL, NULL        },
+	{ XSLFI_TOWN_CARGO_ADJ,         XSCF_IGNORABLE_UNKNOWN,   2,   2, "town_cargo_adj",            NULL, NULL, NULL        },
 	{ XSLFI_SIG_TUNNEL_BRIDGE,      XSCF_NULL,                4,   4, "signal_tunnel_bridge",      NULL, NULL, "XBSS"      },
 	{ XSLFI_IMPROVED_BREAKDOWNS,    XSCF_NULL,                4,   4, "improved_breakdowns",       NULL, NULL, NULL        },
 	{ XSLFI_TT_WAIT_IN_DEPOT,       XSCF_NULL,                1,   1, "tt_wait_in_depot",          NULL, NULL, NULL        },

src/settings_gui.cpp

@@ -1765,7 +1765,7 @@ static SettingsContainer &GetSettingsTree()
 				towns->Add(new SettingEntry("economy.allow_town_roads"));
 				towns->Add(new SettingEntry("economy.allow_town_level_crossings"));
 				towns->Add(new SettingEntry("economy.found_town"));
-				towns->Add(new SettingEntry("economy.town_cargo_factor"));
+				towns->Add(new SettingEntry("economy.town_cargo_scale_factor"));
 				towns->Add(new SettingEntry("economy.random_road_reconstruction"));
 			}
 

src/settings_type.h

@@ -544,7 +544,8 @@ struct EconomySettings {
 	uint   sharing_fee[4];                   ///< fees for infrastructure sharing for rail/road/water/air
 	bool   sharing_payment_in_debt;          ///< allow fee payment for companies with more loan than money (switch off to prevent MP exploits)
 	bool   allow_town_level_crossings;       ///< towns are allowed to build level crossings
-	int8   town_cargo_factor;                ///< power-of-two multiplier for town (passenger, mail) generation. May be negative.
+	int8   old_town_cargo_factor;            ///< old power-of-two multiplier for town (passenger, mail) generation. May be negative.
+	int16  town_cargo_scale_factor;          ///< scaled power-of-two multiplier for town (passenger, mail) generation. May be negative.
 	bool   infrastructure_maintenance;       ///< enable monthly maintenance fee for owner infrastructure
 	uint8  day_length_factor;                ///< factor which the length of day is multiplied
 	uint16 random_road_reconstruction;       ///< chance out of 1000 per tile loop for towns to start random road re-construction

src/table/settings.ini

@@ -677,7 +677,7 @@ str      = STR_CONFIG_SETTING_ALLOW_TOWN_ROADS
 strhelp  = STR_CONFIG_SETTING_ALLOW_TOWN_ROADS_HELPTEXT
 
 [SDT_XREF]
-xref     = ""economy.town_cargo_factor""
+xref     = ""economy.old_town_cargo_factor""
 extver   = SlXvFeatureTest(XSLFTO_AND, XSLFI_SPRINGPP)
 
 [SDT_VAR]
@@ -852,17 +852,31 @@ strhelp  = STR_CONFIG_SETTING_SHORT_PATH_SATURATION_HELPTEXT
 
 [SDT_VAR]
 base     = GameSettings
-var      = economy.town_cargo_factor
+var      = economy.old_town_cargo_factor
 type     = SLE_INT8
-from     = 160
 def      = 0
 min      = -16
 max      = +8
 interval = 1
 str      = STR_CONFIG_SETTING_TOWN_CARGO_FACTOR
-strval	 = STR_JUST_INT
+strval   = STR_JUST_INT
+extver   = SlXvFeatureTest(XSLFTO_AND, XSLFI_TOWN_CARGO_ADJ, 1, 1)
 patxname = ""town_cargo_adj.economy.town_cargo_factor""
 
+[SDT_VAR]
+base     = GameSettings
+var      = economy.town_cargo_scale_factor
+type     = SLE_INT16
+guiflags = SGF_DECIMAL1
+def      = 0
+min      = -160
+max      = +80
+interval = 1
+str      = STR_CONFIG_SETTING_TOWN_CARGO_FACTOR
+strval   = STR_JUST_DECIMAL1
+strhelp  = STR_CONFIG_SETTING_TOWN_CARGO_FACTOR_HELPTEXT
+patxname = ""town_cargo_adj.economy.town_cargo_scale_factor""
+
 ; Vehicles
 
 [SDT_VAR]

src/town_cmd.cpp

@@ -574,13 +574,24 @@ static void MakeTownHouseBigger(TileIndex tile)
 static void TownGenerateCargo (Town *t, CargoID ct, uint amount, StationFinder &stations, bool economy_adjust)
 {
 	// custom cargo generation factor
-	int cf = _settings_game.economy.town_cargo_factor;
+	int factor = _settings_game.economy.town_cargo_scale_factor;
 
 	// when the economy flunctuates, everyone wants to stay at home
 	if (economy_adjust && EconomyIsInRecession()) {
 		amount = (amount + 1) >> 1;
 	}
 
+	factor += 200; // ensure factor is positive
+	assert(factor >= 0);
+	int cf = (factor / 10) - 20;
+	int fine = factor % 10;
+	if (fine != 0) {
+		// 2^0.1 << 16 to 2^0.9 << 16
+		const uint32 adj[9] = {70239, 75281, 80684, 86475, 92681, 99334, 106463, 114104, 122294};
+		uint64 scaled_amount = ((uint64) amount) * ((uint64) adj[fine - 1]);
+		amount = scaled_amount >> 16;
+	}
+
 	// apply custom factor?
 	if (cf < 0) {
 		// approx (amount / 2^cf)