Merge d47951a0a6 into 7546c1acab

The snow coverage was too random, it could produce maps with snow
heights too low or too high with the exact same settings.

Now the snow line height is determined by choosing an aproxiamte level,
similar to the water level. A custom value can also be entered.

src/genworld.h

@@ -49,6 +49,8 @@ static const uint CUSTOM_SEA_LEVEL_NUMBER_DIFFICULTY = 4; ///< Value for custom
 static const uint CUSTOM_SEA_LEVEL_MIN_PERCENTAGE = 1;    ///< Minimum percentage a user can specify for custom sea level.
 static const uint CUSTOM_SEA_LEVEL_MAX_PERCENTAGE = 90;   ///< Maximum percentage a user can specify for custom sea level.
 
+static const uint CUSTOM_SNOW_LEVEL_NUMBER = 5; ///< Value for custom snow level in game creation settings
+
 static constexpr uint MAP_HEIGHT_LIMIT_ORIGINAL = 15; ///< Original map height limit.
 
 static const uint MAP_HEIGHT_LIMIT_AUTO_MINIMUM = 30; ///< When map height limit is auto, make this the lowest possible map height limit.

src/genworld_gui.cpp

@@ -124,7 +124,7 @@ static constexpr NWidgetPart _nested_generate_landscape_widgets[] = {
 					/* Labels on the left side (global column 3). */
 					NWidget(NWID_VERTICAL, NWidContainerFlag::EqualSize), SetPIP(0, WidgetDimensions::unscaled.vsep_sparse, 0),
 						NWidget(NWID_SELECTION, INVALID_COLOUR, WID_GL_CLIMATE_SEL_LABEL),
-							NWidget(WWT_TEXT, INVALID_COLOUR), SetStringTip(STR_MAPGEN_SNOW_COVERAGE, STR_CONFIG_SETTING_SNOW_COVERAGE_HELPTEXT), SetFill(1, 1),
+							NWidget(WWT_TEXT, INVALID_COLOUR), SetStringTip(STR_MAPGEN_SNOW_LINE_LEVEL, STR_CONFIG_SETTING_SNOW_LINE_LEVEL_HELPTEXT), SetFill(1, 1),
 							NWidget(WWT_TEXT, INVALID_COLOUR), SetStringTip(STR_MAPGEN_DESERT_COVERAGE, STR_CONFIG_SETTING_DESERT_COVERAGE_HELPTEXT), SetFill(1, 1),
 							NWidget(NWID_SPACER), SetFill(1, 1),
 						EndContainer(),
@@ -139,11 +139,9 @@ static constexpr NWidgetPart _nested_generate_landscape_widgets[] = {
 					NWidget(NWID_VERTICAL, NWidContainerFlag::EqualSize), SetPIP(0, WidgetDimensions::unscaled.vsep_sparse, 0),
 						/* Climate selector. */
 						NWidget(NWID_SELECTION, INVALID_COLOUR, WID_GL_CLIMATE_SEL_SELECTOR),
-							/* Snow coverage. */
+							/* Snow line level. */
 							NWidget(NWID_HORIZONTAL),
-								NWidget(WWT_IMGBTN, COLOUR_ORANGE, WID_GL_SNOW_COVERAGE_DOWN), SetSpriteTip(SPR_ARROW_DOWN, STR_MAPGEN_SNOW_COVERAGE_DOWN_TOOLTIP), SetFill(0, 1), SetAspect(WidgetDimensions::ASPECT_UP_DOWN_BUTTON),
+								NWidget(WWT_DROPDOWN, COLOUR_ORANGE, WID_GL_SNOW_LINE_LEVEL_PULLDOWN), SetToolTip(STR_CONFIG_SETTING_SNOW_LINE_LEVEL_HELPTEXT), SetFill(1, 1),
-								NWidget(WWT_TEXTBTN, COLOUR_ORANGE, WID_GL_SNOW_COVERAGE_TEXT), SetToolTip(STR_CONFIG_SETTING_SNOW_COVERAGE_HELPTEXT), SetFill(1, 1),
-								NWidget(WWT_IMGBTN, COLOUR_ORANGE, WID_GL_SNOW_COVERAGE_UP), SetSpriteTip(SPR_ARROW_UP, STR_MAPGEN_SNOW_COVERAGE_UP_TOOLTIP), SetFill(0, 1), SetAspect(WidgetDimensions::ASPECT_UP_DOWN_BUTTON),
 							EndContainer(),
 							/* Desert coverage. */
 							NWidget(NWID_HORIZONTAL),
@@ -259,7 +257,7 @@ static constexpr NWidgetPart _nested_heightmap_load_widgets[] = {
 					/* Right half labels (global column 3) */
 					NWidget(NWID_VERTICAL, NWidContainerFlag::EqualSize), SetPIP(0, WidgetDimensions::unscaled.vsep_sparse, 0),
 						NWidget(NWID_SELECTION, INVALID_COLOUR, WID_GL_CLIMATE_SEL_LABEL),
-							NWidget(WWT_TEXT, INVALID_COLOUR), SetStringTip(STR_MAPGEN_SNOW_COVERAGE, STR_CONFIG_SETTING_SNOW_COVERAGE_HELPTEXT), SetFill(1, 1),
+							NWidget(WWT_TEXT, INVALID_COLOUR), SetStringTip(STR_MAPGEN_SNOW_LINE_LEVEL, STR_CONFIG_SETTING_SNOW_LINE_LEVEL_HELPTEXT), SetFill(1, 1),
 							NWidget(WWT_TEXT, INVALID_COLOUR), SetStringTip(STR_MAPGEN_DESERT_COVERAGE, STR_CONFIG_SETTING_DESERT_COVERAGE_HELPTEXT), SetFill(1, 1),
 							NWidget(NWID_SPACER), SetFill(1, 1),
 						EndContainer(),
@@ -273,11 +271,9 @@ static constexpr NWidgetPart _nested_heightmap_load_widgets[] = {
 					NWidget(NWID_VERTICAL, NWidContainerFlag::EqualSize), SetPIP(0, WidgetDimensions::unscaled.vsep_sparse, 0),
 						/* Climate selector. */
 						NWidget(NWID_SELECTION, INVALID_COLOUR, WID_GL_CLIMATE_SEL_SELECTOR),
-							/* Snow coverage. */
+							/* Snow line level. */
 							NWidget(NWID_HORIZONTAL),
-								NWidget(WWT_IMGBTN, COLOUR_ORANGE, WID_GL_SNOW_COVERAGE_DOWN), SetSpriteTip(SPR_ARROW_DOWN, STR_MAPGEN_SNOW_COVERAGE_DOWN_TOOLTIP), SetFill(0, 1), SetAspect(WidgetDimensions::ASPECT_UP_DOWN_BUTTON),
+								NWidget(WWT_DROPDOWN, COLOUR_ORANGE, WID_GL_SNOW_LINE_LEVEL_PULLDOWN), SetToolTip(STR_CONFIG_SETTING_SNOW_LINE_LEVEL_HELPTEXT), SetFill(1, 1),
-								NWidget(WWT_TEXTBTN, COLOUR_ORANGE, WID_GL_SNOW_COVERAGE_TEXT), SetToolTip(STR_CONFIG_SETTING_SNOW_COVERAGE_HELPTEXT), SetFill(1, 1),
-								NWidget(WWT_IMGBTN, COLOUR_ORANGE, WID_GL_SNOW_COVERAGE_UP), SetSpriteTip(SPR_ARROW_UP, STR_MAPGEN_SNOW_COVERAGE_UP_TOOLTIP), SetFill(0, 1), SetAspect(WidgetDimensions::ASPECT_UP_DOWN_BUTTON),
 							EndContainer(),
 							/* Desert coverage. */
 							NWidget(NWID_HORIZONTAL),
@@ -384,6 +380,7 @@ static const StringID _rotation[]    = {STR_CONFIG_SETTING_HEIGHTMAP_ROTATION_CO
 static const StringID _num_towns[]   = {STR_NUM_VERY_LOW, STR_NUM_LOW, STR_NUM_NORMAL, STR_NUM_HIGH, STR_NUM_CUSTOM};
 static const StringID _num_inds[]    = {STR_FUNDING_ONLY, STR_MINIMAL, STR_NUM_VERY_LOW, STR_NUM_LOW, STR_NUM_NORMAL, STR_NUM_HIGH, STR_NUM_CUSTOM};
 static const StringID _variety[]     = {STR_VARIETY_NONE, STR_VARIETY_VERY_LOW, STR_VARIETY_LOW, STR_VARIETY_MEDIUM, STR_VARIETY_HIGH, STR_VARIETY_VERY_HIGH};
+static const StringID _snow_levels[] = {STR_SNOW_LINE_LEVEL_VERY_LOW, STR_SNOW_LINE_LEVEL_LOW, STR_SNOW_LINE_LEVEL_MEDIUM, STR_SNOW_LINE_LEVEL_HIGH, STR_SNOW_LINE_LEVEL_VERY_HIGH, STR_SNOW_LINE_LEVEL_CUSTOM};
 
 static_assert(std::size(_num_inds) == ID_END);
 
@@ -426,7 +423,12 @@ struct GenerateLandscapeWindow : public Window {
 			case WID_GL_MAPSIZE_X_PULLDOWN:   return GetString(STR_JUST_INT, 1LL << _settings_newgame.game_creation.map_x);
 			case WID_GL_MAPSIZE_Y_PULLDOWN:   return GetString(STR_JUST_INT, 1LL << _settings_newgame.game_creation.map_y);
 			case WID_GL_HEIGHTMAP_HEIGHT_TEXT: return GetString(STR_JUST_INT, _settings_newgame.game_creation.heightmap_height);
-			case WID_GL_SNOW_COVERAGE_TEXT:   return GetString(STR_MAPGEN_SNOW_COVERAGE_TEXT, _settings_newgame.game_creation.snow_coverage);
+			case WID_GL_SNOW_LINE_LEVEL_PULLDOWN:
+				if (_settings_newgame.game_creation.snow_line_level == CUSTOM_SNOW_LEVEL_NUMBER) {
+					return GetString(STR_SNOW_LINE_LEVEL_CUSTOM_NUMBER, _settings_newgame.game_creation.snow_line_height);
+				}
+				return GetString(_snow_levels[_settings_newgame.game_creation.snow_line_level]);
+
 			case WID_GL_DESERT_COVERAGE_TEXT: return GetString(STR_MAPGEN_DESERT_COVERAGE_TEXT, _settings_newgame.game_creation.desert_coverage);
 
 			case WID_GL_TOWN_PULLDOWN:
@@ -523,7 +525,7 @@ struct GenerateLandscapeWindow : public Window {
 		}
 
 		/* Disable snowline if not arctic */
-		this->SetWidgetDisabledState(WID_GL_SNOW_COVERAGE_TEXT, _settings_newgame.game_creation.landscape != LandscapeType::Arctic);
+		this->SetWidgetDisabledState(WID_GL_SNOW_LINE_LEVEL_PULLDOWN, _settings_newgame.game_creation.landscape != LandscapeType::Arctic);
 		/* Disable desert if not tropic */
 		this->SetWidgetDisabledState(WID_GL_DESERT_COVERAGE_TEXT, _settings_newgame.game_creation.landscape != LandscapeType::Tropic);
 
@@ -545,8 +547,6 @@ struct GenerateLandscapeWindow : public Window {
 		}
 		this->SetWidgetDisabledState(WID_GL_START_DATE_DOWN, _settings_newgame.game_creation.starting_year <= CalendarTime::MIN_YEAR);
 		this->SetWidgetDisabledState(WID_GL_START_DATE_UP,   _settings_newgame.game_creation.starting_year >= CalendarTime::MAX_YEAR);
-		this->SetWidgetDisabledState(WID_GL_SNOW_COVERAGE_DOWN, _settings_newgame.game_creation.snow_coverage <= 0 || _settings_newgame.game_creation.landscape != LandscapeType::Arctic);
-		this->SetWidgetDisabledState(WID_GL_SNOW_COVERAGE_UP,   _settings_newgame.game_creation.snow_coverage >= 100 || _settings_newgame.game_creation.landscape != LandscapeType::Arctic);
 		this->SetWidgetDisabledState(WID_GL_DESERT_COVERAGE_DOWN, _settings_newgame.game_creation.desert_coverage <= 0 || _settings_newgame.game_creation.landscape != LandscapeType::Tropic);
 		this->SetWidgetDisabledState(WID_GL_DESERT_COVERAGE_UP,   _settings_newgame.game_creation.desert_coverage >= 100 || _settings_newgame.game_creation.landscape != LandscapeType::Tropic);
 
@@ -586,8 +586,8 @@ struct GenerateLandscapeWindow : public Window {
 				d = GetStringBoundingBox(GetString(STR_JUST_INT, GetParamMaxValue(MAX_MAP_SIZE)));
 				break;
 
-			case WID_GL_SNOW_COVERAGE_TEXT:
+			case WID_GL_SNOW_LINE_LEVEL_PULLDOWN:
-				d = GetStringBoundingBox(GetString(STR_MAPGEN_SNOW_COVERAGE_TEXT, GetParamMaxValue(MAX_TILE_HEIGHT)));
+				d = GetStringBoundingBox(GetString(STR_JUST_INT, GetParamMaxValue(MAX_SNOWLINE_HEIGHT)));
 				break;
 
 			case WID_GL_DESERT_COVERAGE_TEXT:
@@ -738,21 +738,8 @@ struct GenerateLandscapeWindow : public Window {
 				ShowQueryString(GetString(STR_JUST_INT, _settings_newgame.game_creation.starting_year), STR_MAPGEN_START_DATE_QUERY_CAPT, 8, this, CS_NUMERAL, QueryStringFlag::EnableDefault);
 				break;
 
-			case WID_GL_SNOW_COVERAGE_DOWN:
+			case WID_GL_SNOW_LINE_LEVEL_PULLDOWN: // Snow line level
-			case WID_GL_SNOW_COVERAGE_UP: // Snow coverage buttons
+				ShowDropDownMenu(this, _snow_levels, _settings_newgame.game_creation.snow_line_level, WID_GL_SNOW_LINE_LEVEL_PULLDOWN, 0, 0);
-				/* Don't allow too fast scrolling */
-				if (!this->flags.Test(WindowFlag::Timeout) || this->timeout_timer <= 1) {
-					this->HandleButtonClick(widget);
-
-					_settings_newgame.game_creation.snow_coverage = Clamp(_settings_newgame.game_creation.snow_coverage + (widget - WID_GL_SNOW_COVERAGE_TEXT) * 10, 0, 100);
-					this->InvalidateData();
-				}
-				_left_button_clicked = false;
-				break;
-
-			case WID_GL_SNOW_COVERAGE_TEXT: // Snow coverage text
-				this->widget_id = WID_GL_SNOW_COVERAGE_TEXT;
-				ShowQueryString(GetString(STR_JUST_INT, _settings_newgame.game_creation.snow_coverage), STR_MAPGEN_SNOW_COVERAGE_QUERY_CAPT, 4, this, CS_NUMERAL, QueryStringFlag::EnableDefault);
 				break;
 
 			case WID_GL_DESERT_COVERAGE_DOWN:
@@ -846,9 +833,9 @@ struct GenerateLandscapeWindow : public Window {
 	void OnTimeout() override
 	{
 		if (mode == GLWM_HEIGHTMAP) {
-			this->RaiseWidgetsWhenLowered(WID_GL_HEIGHTMAP_HEIGHT_DOWN, WID_GL_HEIGHTMAP_HEIGHT_UP, WID_GL_START_DATE_DOWN, WID_GL_START_DATE_UP, WID_GL_SNOW_COVERAGE_UP, WID_GL_SNOW_COVERAGE_DOWN, WID_GL_DESERT_COVERAGE_UP, WID_GL_DESERT_COVERAGE_DOWN);
+			this->RaiseWidgetsWhenLowered(WID_GL_HEIGHTMAP_HEIGHT_DOWN, WID_GL_HEIGHTMAP_HEIGHT_UP, WID_GL_START_DATE_DOWN, WID_GL_START_DATE_UP, WID_GL_DESERT_COVERAGE_UP, WID_GL_DESERT_COVERAGE_DOWN);
 		} else {
-			this->RaiseWidgetsWhenLowered(WID_GL_START_DATE_DOWN, WID_GL_START_DATE_UP, WID_GL_SNOW_COVERAGE_UP, WID_GL_SNOW_COVERAGE_DOWN, WID_GL_DESERT_COVERAGE_UP, WID_GL_DESERT_COVERAGE_DOWN);
+			this->RaiseWidgetsWhenLowered(WID_GL_START_DATE_DOWN, WID_GL_START_DATE_UP, WID_GL_DESERT_COVERAGE_UP, WID_GL_DESERT_COVERAGE_DOWN);
 		}
 	}
 
@@ -863,6 +850,14 @@ struct GenerateLandscapeWindow : public Window {
 
 			case WID_GL_HEIGHTMAP_ROTATION_PULLDOWN: _settings_newgame.game_creation.heightmap_rotation = index; break;
 
+			case WID_GL_SNOW_LINE_LEVEL_PULLDOWN: // Snow line level
+				if ((uint)index == CUSTOM_SNOW_LEVEL_NUMBER) {
+					this->widget_id = widget;
+					ShowQueryString(GetString(STR_JUST_INT, _settings_newgame.game_creation.snow_line_height), STR_MAPGEN_SNOW_LINE_LEVEL_QUERY_CAPT, 4, this, CS_NUMERAL, {});
+				}
+				_settings_newgame.game_creation.snow_line_level = index;
+				break;
+
 			case WID_GL_TOWN_PULLDOWN:
 				if ((uint)index == CUSTOM_TOWN_NUMBER_DIFFICULTY) {
 					this->widget_id = widget;
@@ -922,7 +917,7 @@ struct GenerateLandscapeWindow : public Window {
 			switch (this->widget_id) {
 				case WID_GL_HEIGHTMAP_HEIGHT_TEXT: value = MAP_HEIGHT_LIMIT_AUTO_MINIMUM; break;
 				case WID_GL_START_DATE_TEXT: value = CalendarTime::DEF_START_YEAR.base(); break;
-				case WID_GL_SNOW_COVERAGE_TEXT: value = DEF_SNOW_COVERAGE; break;
+				case WID_GL_SNOW_LINE_LEVEL_PULLDOWN: value = DEF_SNOWLINE_HEIGHT; break;
 				case WID_GL_DESERT_COVERAGE_TEXT: value = DEF_DESERT_COVERAGE; break;
 				case WID_GL_TOWN_PULLDOWN: value = 1; break;
 				case WID_GL_INDUSTRY_PULLDOWN: value = 1; break;
@@ -943,9 +938,8 @@ struct GenerateLandscapeWindow : public Window {
 				_settings_newgame.game_creation.starting_year = Clamp(TimerGameCalendar::Year(value), CalendarTime::MIN_YEAR, CalendarTime::MAX_YEAR);
 				break;
 
-			case WID_GL_SNOW_COVERAGE_TEXT:
+			case WID_GL_SNOW_LINE_LEVEL_PULLDOWN:
-				this->SetWidgetDirty(WID_GL_SNOW_COVERAGE_TEXT);
+				_settings_newgame.game_creation.snow_line_height = Clamp(value, MIN_SNOWLINE_HEIGHT, MAX_SNOWLINE_HEIGHT);
-				_settings_newgame.game_creation.snow_coverage = Clamp(value, 0, 100);
 				break;
 
 			case WID_GL_DESERT_COVERAGE_TEXT:

src/landscape.cpp

@@ -1510,13 +1510,45 @@ static uint CalculateCoverageLine(uint coverage, uint edge_multiplier)
 	return best_h;
 }
 
+/**
+ * Get current maximum height of the map.
+ * @return The maximum height of the map.
+ */
+static uint GetMapMaxHeight()
+{
+	uint max_height = 0;
+
+	for (const auto tile : Map::Iterate()) {
+		uint h = TileHeight(tile);
+		if (h > max_height) {
+			max_height = h;
+		}
+	}
+
+	return max_height;
+}
+
 /**
  * Calculate the line from which snow begins.
  */
 static void CalculateSnowLine()
 {
-	/* We do not have snow sprites on coastal tiles, so never allow "1" as height. */
+	/* If snow_line_level is custom, then snow_line_height is already set
-	_settings_game.game_creation.snow_line_height = std::max(CalculateCoverageLine(_settings_game.game_creation.snow_coverage, 0), 2u);
+	 * otherwise we have to calculate it
+	 */
+	if (_settings_game.game_creation.snow_line_level != CUSTOM_SNOW_LEVEL_NUMBER) {
+		uint min_snow_line_height = 4;                              // Not too low to make room for farms
+		uint max_snow_line_height = GetMapMaxHeight() - 2;          // Not too high to make room for forests
+
+		uint max_height_diff = min_snow_line_height < max_snow_line_height
+			? max_snow_line_height - min_snow_line_height
+			: 0;
+
+		/* snow_line_level goes up to 4 so we divide by 5 to get a maximum ratio of 80% */
+		uint height_diff = RoundDivSU(max_height_diff * _settings_game.game_creation.snow_line_level, 5);
+
+		_settings_game.game_creation.snow_line_height = min_snow_line_height + height_diff;
+	}
 }
 
 /**

src/lang/english.txt

@@ -1217,6 +1217,15 @@ STR_TERRAIN_TYPE_ALPINIST                                       :Alpinist
 STR_TERRAIN_TYPE_CUSTOM                                         :Custom height
 STR_TERRAIN_TYPE_CUSTOM_VALUE                                   :Custom height ({NUM})
 
+###length 7
+STR_SNOW_LINE_LEVEL_VERY_LOW                                    :Very Low
+STR_SNOW_LINE_LEVEL_LOW                                         :Low
+STR_SNOW_LINE_LEVEL_MEDIUM                                      :Medium
+STR_SNOW_LINE_LEVEL_HIGH                                        :High
+STR_SNOW_LINE_LEVEL_VERY_HIGH                                   :Very high
+STR_SNOW_LINE_LEVEL_CUSTOM                                      :Custom
+STR_SNOW_LINE_LEVEL_CUSTOM_NUMBER                               :Custom ({NUM})
+
 ###length 4
 STR_CITY_APPROVAL_LENIENT                                       :Lenient
 STR_CITY_APPROVAL_TOLERANT                                      :Tolerant
@@ -1593,9 +1602,8 @@ STR_CONFIG_SETTING_OIL_REF_EDGE_DISTANCE_HELPTEXT               :Limit for how f
 STR_CONFIG_SETTING_SNOWLINE_HEIGHT                              :Snow line height: {STRING2}
 STR_CONFIG_SETTING_SNOWLINE_HEIGHT_HELPTEXT                     :Choose at what height snow starts in sub-arctic landscape. Snow also affects industry generation and town growth requirements. Can only be modified via Scenario Editor or is otherwise calculated via "snow coverage"
 
-STR_CONFIG_SETTING_SNOW_COVERAGE                                :Snow coverage: {STRING2}
+STR_CONFIG_SETTING_SNOW_LINE_LEVEL                              :Snow line level: {STRING2}
-STR_CONFIG_SETTING_SNOW_COVERAGE_HELPTEXT                       :Choose the approximate amount of snow on the sub-arctic landscape. Snow also affects industry generation and town growth requirements. Only used during map generation. Sea level and coast tiles never have snow
+STR_CONFIG_SETTING_SNOW_LINE_LEVEL_HELPTEXT                     :Choose the approximate height above which all tiles will be covered by snow in sub-arctic landscape. Snow also affects industry generation and town growth requirements.
-STR_CONFIG_SETTING_SNOW_COVERAGE_VALUE                          :{NUM}%
 
 STR_CONFIG_SETTING_DESERT_COVERAGE                              :Desert coverage: {STRING2}
 STR_CONFIG_SETTING_DESERT_COVERAGE_HELPTEXT                     :Choose the approximate amount of desert on the tropical landscape. Desert also affects industry generation and town growth requirements. Only used during map generation
@@ -3352,10 +3360,7 @@ STR_MAPGEN_HEIGHTMAP_HEIGHT                                     :{BLACK}Highest
 STR_MAPGEN_HEIGHTMAP_HEIGHT_TOOLTIP                             :{BLACK}Choose the highest peak that the game will attempt to create, measured in elevation above sea level
 STR_MAPGEN_HEIGHTMAP_HEIGHT_UP_TOOLTIP                          :{BLACK}Increase the maximum height of highest peak on the map by one
 STR_MAPGEN_HEIGHTMAP_HEIGHT_DOWN_TOOLTIP                        :{BLACK}Decrease the maximum height of highest peak on the map by one
-STR_MAPGEN_SNOW_COVERAGE                                        :{BLACK}Snow coverage:
+STR_MAPGEN_SNOW_LINE_LEVEL                                      :{BLACK}Snow line level:
-STR_MAPGEN_SNOW_COVERAGE_UP_TOOLTIP                             :{BLACK}Increase snow coverage by ten percent
-STR_MAPGEN_SNOW_COVERAGE_DOWN_TOOLTIP                           :{BLACK}Decrease snow coverage by ten percent
-STR_MAPGEN_SNOW_COVERAGE_TEXT                                   :{BLACK}{NUM}%
 STR_MAPGEN_DESERT_COVERAGE                                      :{BLACK}Desert coverage:
 STR_MAPGEN_DESERT_COVERAGE_UP_TOOLTIP                           :{BLACK}Increase desert coverage by ten percent
 STR_MAPGEN_DESERT_COVERAGE_DOWN_TOOLTIP                         :{BLACK}Decrease desert coverage by ten percent
@@ -3420,7 +3425,7 @@ STR_MAPGEN_HEIGHTMAP_SIZE                                       :{ORANGE}{NUM} x
 
 STR_MAPGEN_TERRAIN_TYPE_QUERY_CAPT                              :{WHITE}Target peak height
 STR_MAPGEN_HEIGHTMAP_HEIGHT_QUERY_CAPT                          :{WHITE}Highest peak
-STR_MAPGEN_SNOW_COVERAGE_QUERY_CAPT                             :{WHITE}Snow coverage (in %)
+STR_MAPGEN_SNOW_LINE_LEVEL_QUERY_CAPT                           :{WHITE}Snow line height
 STR_MAPGEN_DESERT_COVERAGE_QUERY_CAPT                           :{WHITE}Desert coverage (in %)
 STR_MAPGEN_START_DATE_QUERY_CAPT                                :{WHITE}Change starting year
 

src/saveload/afterload.cpp

@@ -66,6 +66,7 @@
 #include "../timer/timer_game_economy.h"
 #include "../timer/timer_game_tick.h"
 #include "../picker_func.h"
+#include "../genworld.h"
 
 #include "saveload_internal.h"
 
@@ -3397,6 +3398,11 @@ bool AfterLoadGame()
 		}
 	}
 
+	if (IsSavegameVersionBefore(SLV_SNOW_LINE_LEVEL)) {
+		/* The snow line level replaces the snow coverage but the two do not map very well. */
+		_settings_game.game_creation.snow_line_level = CUSTOM_SNOW_LEVEL_NUMBER;
+	}
+
 	AfterLoadLabelMaps();
 	AfterLoadCompanyStats();
 	AfterLoadStoryBook();

src/saveload/compat/settings_sl_compat.h

@@ -143,7 +143,7 @@ const SaveLoadCompat _settings_sl_compat[] = {
 	SLC_VAR("economy.fund_roads"),
 	SLC_VAR("economy.give_money"),
 	SLC_VAR("game_creation.snow_line_height"),
-	SLC_VAR("game_creation.snow_coverage"),
+	SLC_NULL(1, SLV_MAPGEN_SETTINGS_REVAMP, SLV_TABLE_CHUNKS),
 	SLC_VAR("game_creation.desert_coverage"),
 	SLC_NULL(4, SL_MIN_VERSION, SLV_144),
 	SLC_VAR("game_creation.starting_year"),

src/saveload/saveload.h

@@ -405,6 +405,7 @@ enum SaveLoadVersion : uint16_t {
 
 	SLV_FACE_STYLES,                        ///< 355  PR#14319 Addition of face styles, replacing gender and ethnicity.
 	SLV_INDUSTRY_NUM_VALID_HISTORY,         ///< 356  PR#14416 Store number of valid history records for industries.
+	SLV_SNOW_LINE_LEVEL,                    ///< 357  PR#14428 Replacement of snow coverage setting with snow line level setting
 
 	SL_MAX_VERSION,                         ///< Highest possible saveload version
 };

src/settingentry_gui.cpp

@@ -842,7 +842,7 @@ SettingsContainer &GetSettingsTree()
 			genworld->Add(new SettingEntry("difficulty.terrain_type"));
 			genworld->Add(new SettingEntry("game_creation.tgen_smoothness"));
 			genworld->Add(new SettingEntry("game_creation.variety"));
-			genworld->Add(new SettingEntry("game_creation.snow_coverage"));
+			genworld->Add(new SettingEntry("game_creation.snow_line_level"));
 			genworld->Add(new SettingEntry("game_creation.snow_line_height"));
 			genworld->Add(new SettingEntry("game_creation.desert_coverage"));
 			genworld->Add(new SettingEntry("game_creation.amount_of_rivers"));

src/settings_type.h

@@ -363,8 +363,8 @@ struct GameCreationSettings {
 	uint8_t  map_y;                            ///< Y size of map
 	uint8_t land_generator;                   ///< the landscape generator
 	uint8_t oil_refinery_limit;               ///< distance oil refineries allowed from map edge
-	uint8_t snow_line_height;                 ///< the configured snow line height (deduced from "snow_coverage")
+	uint8_t snow_line_height;                 ///< the configured snow line height (deduced from "snow_line_level" unless it is set on "custom")
-	uint8_t snow_coverage;                    ///< the amount of snow coverage on the map
+	uint8_t snow_line_level;                  ///< the approximate snow line level on the map
 	uint8_t desert_coverage;                  ///< the amount of desert coverage on the map
 	uint8_t heightmap_height;                 ///< highest mountain for heightmap (towards what it scales)
 	uint8_t tgen_smoothness;                  ///< how rough is the terrain from 0-3

src/table/settings/world_settings.ini

@@ -97,17 +97,17 @@ strval   = STR_JUST_COMMA
 cat      = SC_BASIC
 
 [SDT_VAR]
-var      = game_creation.snow_coverage
+var      = game_creation.snow_line_level
 type     = SLE_UINT8
-from     = SLV_MAPGEN_SETTINGS_REVAMP
+from     = SLV_SNOW_LINE_LEVEL
-flags    = SettingFlag::NewgameOnly
+flags    = SettingFlag::GuiDropdown, SettingFlag::NewgameOnly
-def      = DEF_SNOW_COVERAGE
+def      = 1
 min      = 0
-max      = 100
+max      = 5
-interval = 10
+interval = 1
-str      = STR_CONFIG_SETTING_SNOW_COVERAGE
+str      = STR_CONFIG_SETTING_SNOW_LINE_LEVEL
-strhelp  = STR_CONFIG_SETTING_SNOW_COVERAGE_HELPTEXT
+strhelp  = STR_CONFIG_SETTING_SNOW_LINE_LEVEL_HELPTEXT
-strval   = STR_CONFIG_SETTING_SNOW_COVERAGE_VALUE
+strval   = STR_SNOW_LINE_LEVEL_VERY_LOW
 cat      = SC_BASIC
 
 [SDT_VAR]

src/tile_type.h

@@ -33,7 +33,6 @@ static const uint MIN_SNOWLINE_HEIGHT = 2;                     ///< Minimum snow
 static const uint DEF_SNOWLINE_HEIGHT = 10;                    ///< Default snowline height
 static const uint MAX_SNOWLINE_HEIGHT = (MAX_TILE_HEIGHT - 2); ///< Maximum allowed snowline height
 
-static const uint DEF_SNOW_COVERAGE = 40;                      ///< Default snow coverage.
 static const uint DEF_DESERT_COVERAGE = 50;                    ///< Default desert coverage.
 
 

src/widgets/genworld_widget.h

@@ -34,9 +34,7 @@ enum GenerateLandscapeWidgets : WidgetID {
 	WID_GL_START_DATE_TEXT,             ///< Start year.
 	WID_GL_START_DATE_UP,               ///< Increase start year.
 
-	WID_GL_SNOW_COVERAGE_DOWN,          ///< Decrease snow coverage.
+	WID_GL_SNOW_LINE_LEVEL_PULLDOWN,    ///< Snow line level.
-	WID_GL_SNOW_COVERAGE_TEXT,          ///< Snow coverage.
-	WID_GL_SNOW_COVERAGE_UP,            ///< Increase snow coverage.
 
 	WID_GL_DESERT_COVERAGE_DOWN,        ///< Decrease desert coverage.
 	WID_GL_DESERT_COVERAGE_TEXT,        ///< Desert coverage.