Feature: Permanent rivers

- Rivers are indestructible, unless cheating or in the scenario editor.
- Added a game setting that can turn on or off this feature.
- Savegame conversion.

Other changes:
- Demolishing a canal that was built on rivers will restore the river, regardless of setting value.
- Can no longer use terraform tool to remove rivers, must demolish them first, regardless of setting value.

docs/landscape.html

@@ -998,6 +998,7 @@ <h3><a name="Landscape">Landscape</a></h3>
      <li>m7: animation frame (railway stations/waypoints, airports)</li>
      <li>m8 bits 11..6: <a href="#TramType">Tramtype</a></li>
      <li>m8 bits 5..0: <a href="#TrackType">track type</a> for railway stations/waypoints</li>
+     <li>m8 bit 15: set if a river was originally present under water based station tiles when current water class is canal (dock, buoy, oilrig)</li>
     </ul>
    </td>
   </tr>
@@ -1108,6 +1109,7 @@ <h3><a name="Landscape">Landscape</a></h3>
        </tr>
       </table>
      </li>
+     <li>m8 bit 15: set if a river was originally present at the tile when current water class is canal (canal, ship depot, lock)</li>
     </ul>
    </td>
   </tr>
@@ -1450,6 +1452,7 @@ <h3><a name="Landscape">Landscape</a></h3>
      <li>m6 bits 5..3: random triggers (NewGRF)</li>
      <li>m6 bit 2: bit 8 of type (see m5)</li>
      <li>m7: animation frame</li>
+     <li>m8 bit 15: set if a river was originally present at the tile when current water class is canal (oilrig)
     </ul>
    </td>
   </tr>
@@ -1622,6 +1625,7 @@ <h3><a name="Landscape">Landscape</a></h3>
      <li>m3: random bits</li>
      <li>m5: index into the array of objects, bits 16 to 23 (lower bits in m2)</li>
      <li>m7: animation counter</li>
+     <li>m8 bit 15: set if a river was originally present at the tile when current water class is canal</li>
     </ul>
    </td>
   </tr>

docs/landscape_grid.html

@@ -79,8 +79,8 @@ <h3 style="font-weight: bold;">Landscape</h3>
     <tr>
       <td rowspan="2">0</td>
       <td class="caption">ground</td>
-      <td class="bits" rowspan=27><span class="used" title="Tile type">XXXX</span> <span class="used" title="Presence and direction of bridge above">XX</span> <span class="used" title="Tropic Zone: only meaningful in tropic climate. It contains the definition of the available zones">XX</span></td>
-      <td class="bits" rowspan=27><span class="used" title="Tile height">XXXX XXXX</span></td>
+      <td class="bits" rowspan=28><span class="used" title="Tile type">XXXX</span> <span class="used" title="Presence and direction of bridge above">XX</span> <span class="used" title="Tropic Zone: only meaningful in tropic climate. It contains the definition of the available zones">XX</span></td>
+      <td class="bits" rowspan=28><span class="used" title="Tile height">XXXX XXXX</span></td>
       <td class="bits" rowspan=2><span class="free">OOO</span><span class="usable" title="Owner (always OWNER_NONE)">1 OOOO</span></td>
       <td class="bits"><span class="free">OOOO OOOO OOOO OOOO</span></td>
       <td class="bits"><span class="used" title="Type of hedge on NE border">XXX</span> <span class="used" title="Snow presence">X</span><span class="free">OOOO</span></td>
@@ -211,14 +211,15 @@ <h3 style="font-weight: bold;">Landscape</h3>
       <td class="bits"><span class="free">OOOO OOOO</span></td>
       <td class="bits"><span class="used" title="Graphics index">XXXX XXXX</span></td>
       <td class="bits"><span class="used" title="Animation frame">XXXX XXXX</span></td>
-      <td class="bits" rowspan=4><span class="free">OOOO OOOO OOOO OOOO</span></td>
+      <td class="bits"><span class="free">OOOO OOOO OOOO OOOO</span></td>
     </tr>
     <tr>
       <td class="caption">dock</td>
       <td class="bits"><span class="free">OOOO OOOO</span></td>
       <td class="bits"><span class="free">OOOO OOOO</span></td>
       <td class="bits"><span class="usable" title="Graphics index">OOOO </span><span class="usable" title="Graphics index">O</span><span class="used" title="Graphics index">XXX</span></td>
       <td class="bits"><span class="free">OOOO OOOO</span></td>
+      <td class="bits" rowspan=3><span class="used" title="Canal on river presence">X</span><span class="free">OOO OOOO OOOO OOOO</span></td>
     </tr>
     <tr>
       <td class="caption">buoy</td>
@@ -235,21 +236,25 @@ <h3 style="font-weight: bold;">Landscape</h3>
       <td class="bits"><span class="free">OOOO OOOO</span></td>
     </tr>
     <tr>
-      <td rowspan=4>6</td>
+      <td rowspan=5>6</td>
       <td class="caption">sea, shore</td>
-      <td class="bits" rowspan=4><span class="used" title="Ship docking tile status">X</span> <span class="used" title="Water class">XX</span> <span class="used" title="Owner">XXXXX</span></td>
-      <td class="bits" rowspan=3><span class="free">OOOO OOOO OOOO OOOO</span></td>
-      <td class="bits" rowspan=4><span class="free">OOOO OOOO</span></td>
+      <td class="bits" rowspan=5><span class="used" title="Ship docking tile status">X</span> <span class="used" title="Water class">XX</span> <span class="used" title="Owner">XXXXX</span></td>
+      <td class="bits" rowspan=4><span class="free">OOOO OOOO OOOO OOOO</span></td>
+      <td class="bits" rowspan=5><span class="free">OOOO OOOO</span></td>
       <td class="bits"><span class="free">OOOO OOOO</span></td>
       <td class="bits"><span class="used" title="Water tile type: coast, clear, lock, depot">O<span class="usable">OO</span>O</span> <span class="free">OOO</span><span class="used" title="Sea shore flag">X</span></td>
-      <td class="bits" rowspan=4><span class="free">OOOO OOOO</span></td>
-      <td class="bits" rowspan=4><span class="free">OOOO OOOO</td>
-      <td class="bits" rowspan=4><span class="free">OOOO OOOO OOOO OOOO</span></td>
+      <td class="bits" rowspan=5><span class="free">OOOO OOOO</span></td>
+      <td class="bits" rowspan=5><span class="free">OOOO OOOO</td>
+      <td class="bits" rowspan=2><span class="free">OOOO OOOO OOOO OOOO</span></td>
+    </tr>
+    <tr>
+      <td class="caption">river</td>
+      <td class="bits" rowspan=2><span class="used" title="Canal/river random bits">XXXX XXXX</span></td>
+      <td class="bits" rowspan=2><span class="used" title="Water tile type: coast, clear, lock, depot">O<span class="usable">OO</span>O</span> <span class="free">OOOO</span></td>
     </tr>
     <tr>
-      <td class="caption">canal, river</td>
-      <td class="bits"><span class="used" title="Canal/river random bits">XXXX XXXX</span></td>
-      <td class="bits"><span class="used" title="Water tile type: coast, clear, lock, depot">O<span class="usable">OO</span>O</span> <span class="free">OOOO</span></td>
+      <td class="caption">canal</td>
+      <td class="bits" rowspan=3><span class="used" title="Canal on river presence">X</span><span class="free">OOO OOOO OOOO OOOO</span></td>
     </tr>
     <tr>
       <td class="caption">lock</td>
@@ -272,7 +277,7 @@ <h3 style="font-weight: bold;">Landscape</h3>
       <td class="bits" rowspan=2><span class="used" title="Industry graphics ID (m5 + m6[2])">XXXX XXXX</span></td>
       <td class="bits" rowspan=2><span class="free">OO</span><span class="used" title="Random triggers (NewGRF)">XXX</span> <span class="used" title="Industry graphics ID (m5 + m6[2])">X</span><span class="free">OO</span></td>
       <td class="bits" rowspan=2><span class="used" title="Animation frame">XXXX XXXX</span></td>
-      <td class="bits" rowspan=2><span class="free">OOOO OOOO OOOO OOOO</span></td>
+      <td class="bits" rowspan=2><span class="used" title="Canal on river presence">X</span><span class="free">OOO OOOO OOOO OOOO</span></td>
     </tr>
     <tr>
       <td class="caption">industry under construction</td>
@@ -305,7 +310,7 @@ <h3 style="font-weight: bold;">Landscape</h3>
       <td class="bits"><span class="pool" title="Object index on pool (m2 + m5)">XXXX XXXX</span></td>
       <td class="bits"><span class="free">OOOO OOOO</span></td>
       <td class="bits"><span class="used" title="Animation counter">XXXX XXXX</span></td>
-      <td class="bits" rowspan=1><span class="free">OOOO OOOO OOOO OOOO</span></td>
+      <td class="bits"><span class="used" title="Canal on river presence">X</span><span class="free">OOO OOOO OOOO OOOO</span></td>
     </tr>
     <tr>
       <td colspan=2 class="caption">bits</td>

src/industry_cmd.cpp

@@ -1884,10 +1884,12 @@ static void DoCreateNewIndustry(Industry *i, TileIndex tile, IndustryType type,
 			i->location.Add(cur_tile);
 
 			WaterClass wc = (IsWaterTile(cur_tile) ? GetWaterClass(cur_tile) : WATER_CLASS_INVALID);
+			bool river = HasTileCanalOnRiver(cur_tile);
 
 			Command<CMD_LANDSCAPE_CLEAR>::Do(DC_EXEC | DC_NO_TEST_TOWN_RATING | DC_NO_MODIFY_TOWN_RATING, cur_tile);
 
 			MakeIndustry(cur_tile, i->index, it.gfx, Random(), wc);
+			if (river) SetCanalOnRiver(cur_tile);
 
 			if (_generating_world) {
 				SetIndustryConstructionCounter(cur_tile, 3);

src/lang/english.txt

@@ -1280,6 +1280,9 @@ STR_CONFIG_SETTING_SERVE_NEUTRAL_INDUSTRIES_HELPTEXT            :When enabled, i
 STR_CONFIG_SETTING_EXTRADYNAMITE                                :Allow removal of more town-owned roads, bridges and tunnels: {STRING2}
 STR_CONFIG_SETTING_EXTRADYNAMITE_HELPTEXT                       :Make it easier to remove town-owned infrastructure and buildings
 
+STR_CONFIG_SETTING_DYNAMITE_RIVER                               :Allow removal of rivers: {STRING2}
+STR_CONFIG_SETTING_DYNAMITE_RIVER_HELPTEXT                      :If disabled, rivers are indestructible and become a permanent part of the landscape
+
 STR_CONFIG_SETTING_TRAIN_LENGTH                                 :Maximum length of trains: {STRING2}
 STR_CONFIG_SETTING_TRAIN_LENGTH_HELPTEXT                        :Set the maximum length of trains
 STR_CONFIG_SETTING_TILE_LENGTH                                  :{COMMA} tile{P 0 "" s}
@@ -3005,6 +3008,7 @@ STR_LAI_STATION_DESCRIPTION_WAYPOINT                            :Waypoint
 
 STR_LAI_WATER_DESCRIPTION_WATER                                 :Water
 STR_LAI_WATER_DESCRIPTION_CANAL                                 :Canal
+STR_LAI_WATER_DESCRIPTION_CANALISED_RIVER                       :Canalised river
 STR_LAI_WATER_DESCRIPTION_LOCK                                  :Lock
 STR_LAI_WATER_DESCRIPTION_RIVER                                 :River
 STR_LAI_WATER_DESCRIPTION_COAST_OR_RIVERBANK                    :Coast or riverbank
@@ -4890,6 +4894,7 @@ STR_ERROR_CAN_T_BUILD_ON_CANAL                                  :{WHITE}... can'
 STR_ERROR_CAN_T_BUILD_ON_RIVER                                  :{WHITE}... can't build on river
 STR_ERROR_MUST_DEMOLISH_CANAL_FIRST                             :{WHITE}Must demolish canal first
 STR_ERROR_CAN_T_BUILD_AQUEDUCT_HERE                             :{WHITE}Can't build aqueduct here...
+STR_ERROR_MUST_CLEAR_RIVER_FIRST                                :{WHITE}Must clear river first
 
 # Tree related errors
 STR_ERROR_TREE_ALREADY_HERE                                     :{WHITE}... tree already here

src/saveload/afterload.cpp

@@ -3148,6 +3148,11 @@ bool AfterLoadGame()
 		}
 	}
 
+	if (IsSavegameVersionBefore(SLV_PERMANENT_RIVERS)) {
+		/* When loading an older savegame version, treat 'dynamite river' as enabled. */
+		_settings_game.construction.dynamite_river = true;
+	}
+
 	/* Compute station catchment areas. This is needed here in case UpdateStationAcceptance is called below. */
 	Station::RecomputeCatchmentForAll();
 

src/saveload/saveload.h

@@ -341,6 +341,8 @@ enum SaveLoadVersion : uint16 {
 	SLV_DOCK_DOCKINGTILES,                  ///< 298  PR#9578 All tiles around docks may be docking tiles.
 	SLV_REPAIR_OBJECT_DOCKING_TILES,        ///< 299  PR#9594 v12.0  Fixing issue with docking tiles overlapping objects.
 
+	SLV_PERMANENT_RIVERS,                   ///< 300  PR#8461 Permanent rivers.
+
 	SL_MAX_VERSION,                         ///< Highest possible saveload version
 };
 

src/settings_gui.cpp

@@ -1737,6 +1737,7 @@ static SettingsContainer &GetSettingsTree()
 			limitations->Add(new SettingEntry("construction.command_pause_level"));
 			limitations->Add(new SettingEntry("construction.autoslope"));
 			limitations->Add(new SettingEntry("construction.extra_dynamite"));
+			limitations->Add(new SettingEntry("construction.dynamite_river"));
 			limitations->Add(new SettingEntry("construction.map_height_limit"));
 			limitations->Add(new SettingEntry("construction.max_bridge_length"));
 			limitations->Add(new SettingEntry("construction.max_bridge_height"));

src/settings_type.h

@@ -343,6 +343,7 @@ struct ConstructionSettings {
 	bool   extra_dynamite;                   ///< extra dynamite
 	bool   road_stop_on_town_road;           ///< allow building of drive-through road stops on town owned roads
 	bool   road_stop_on_competitor_road;     ///< allow building of drive-through road stops on roads owned by competitors
+	bool   dynamite_river;                   ///< allow removal of rivers
 	uint8  raw_industry_construction;        ///< type of (raw) industry construction (none, "normal", prospecting)
 	uint8  industry_platform;                ///< the amount of flat land around an industry
 	bool   freeform_edges;                   ///< allow terraforming the tiles at the map edges

src/station_cmd.cpp

@@ -2511,6 +2511,7 @@ CommandCost CmdBuildDock(DoCommandFlag flags, TileIndex tile, StationID station_
 
 	/* Get the water class of the water tile before it is cleared.*/
 	WaterClass wc = GetWaterClass(tile_cur);
+	bool river = HasTileCanalOnRiver(tile_cur);
 
 	ret = Command<CMD_LANDSCAPE_CLEAR>::Do(flags, tile_cur);
 	if (ret.Failed()) return ret;
@@ -2549,6 +2550,7 @@ CommandCost CmdBuildDock(DoCommandFlag flags, TileIndex tile, StationID station_
 		Company::Get(st->owner)->infrastructure.station += 2;
 
 		MakeDock(tile, st->owner, st->index, direction, wc);
+		if (river) SetCanalOnRiver(tile + TileOffsByDiagDir(direction));
 		UpdateStationDockingTiles(st);
 
 		st->AfterStationTileSetChange(true, STATION_DOCK);

src/station_map.h

@@ -542,7 +542,7 @@ static inline void MakeStation(TileIndex t, Owner o, StationID sid, StationType
 	SB(_me[t].m6, 2, 1, 0);
 	SB(_me[t].m6, 3, 3, st);
 	_me[t].m7 = 0;
-	_me[t].m8 = 0;
+	SB(_me[t].m8, 0, 15, 0);
 }
 
 /**

src/table/settings/world_settings.ini

@@ -429,6 +429,14 @@ def      = true
 str      = STR_CONFIG_SETTING_EXTRADYNAMITE
 strhelp  = STR_CONFIG_SETTING_EXTRADYNAMITE_HELPTEXT
 
+[SDT_BOOL]
+var      = construction.dynamite_river
+from     = SLV_PERMANENT_RIVERS
+def      = true
+str      = STR_CONFIG_SETTING_DYNAMITE_RIVER
+strhelp  = STR_CONFIG_SETTING_DYNAMITE_RIVER_HELPTEXT
+cat      = SC_BASIC
+
 [SDT_VAR]
 var      = construction.max_bridge_length
 type     = SLE_UINT16

src/water_cmd.cpp

@@ -37,6 +37,7 @@
 #include "company_gui.h"
 #include "newgrf_generic.h"
 #include "industry.h"
+#include "cheat_type.h"
 #include "water_cmd.h"
 #include "landscape_cmd.h"
 
@@ -238,15 +239,27 @@ void MakeWaterKeepingClass(TileIndex tile, Owner o)
 		wc = WATER_CLASS_CANAL;
 	}
 
+	bool river = HasTileCanalOnRiver(tile);
 	/* Zero map array and terminate animation */
 	DoClearSquare(tile);
 
 	/* Maybe change to water */
 	switch (wc) {
-		case WATER_CLASS_SEA:   MakeSea(tile);                break;
-		case WATER_CLASS_CANAL: MakeCanal(tile, o, Random()); break;
-		case WATER_CLASS_RIVER: MakeRiver(tile, Random());    break;
-		default: break;
+		case WATER_CLASS_SEA:
+			MakeSea(tile);
+			break;
+
+		case WATER_CLASS_CANAL:
+			MakeCanal(tile, o, Random());
+			if (river) SetCanalOnRiver(tile);
+			break;
+
+		case WATER_CLASS_RIVER:
+			MakeRiver(tile, Random());
+			break;
+
+		default:
+			break;
 	}
 
 	if (wc != WATER_CLASS_INVALID) CheckForDockingTile(tile);
@@ -472,6 +485,7 @@ CommandCost CmdBuildCanal(DoCommandFlag flags, TileIndex tile, TileIndex start_t
 		/* Outside the editor, prevent building canals over your own or OWNER_NONE owned canals */
 		if (water && IsCanal(current_tile) && _game_mode != GM_EDITOR && (IsTileOwner(current_tile, _current_company) || IsTileOwner(current_tile, OWNER_NONE))) continue;
 
+		bool river = (HasTileCanalOnRiver(current_tile) && wc == WATER_CLASS_CANAL) || (HasTileWaterClass(current_tile) && GetWaterClass(current_tile) == WATER_CLASS_RIVER);
 		ret = Command<CMD_LANDSCAPE_CLEAR>::Do(flags, current_tile);
 		if (ret.Failed()) return ret;
 
@@ -503,6 +517,7 @@ CommandCost CmdBuildCanal(DoCommandFlag flags, TileIndex tile, TileIndex start_t
 					}
 
 					MakeCanal(current_tile, _current_company, Random());
+					if (river) SetCanalOnRiver(current_tile);
 					break;
 			}
 			MarkTileDirtyByTile(current_tile);
@@ -543,15 +558,24 @@ static CommandCost ClearTile_Water(TileIndex tile, DoCommandFlag flags)
 				if (ret.Failed()) return ret;
 			}
 
+			if (IsRiver(tile) && _game_mode == GM_NORMAL && !_settings_game.construction.dynamite_river && !_cheats.magic_bulldozer.value) {
+				return CommandCost();
+			}
+
 			if (flags & DC_EXEC) {
 				if (IsCanal(tile) && Company::IsValidID(owner)) {
 					Company::Get(owner)->infrastructure.water--;
 					DirtyCompanyInfrastructureWindows(owner);
 				}
 				bool remove = IsDockingTile(tile);
+				bool river = HasTileCanalOnRiver(tile);
 				DoClearSquare(tile);
+				if (river) {
+					MakeRiver(tile, Random());
+				} else if (remove) {
+					RemoveDockingTile(tile);
+				}
 				MarkCanalsAndRiversAroundDirty(tile);
-				if (remove) RemoveDockingTile(tile);
 			}
 
 			return CommandCost(EXPENSES_CONSTRUCTION, base_cost);
@@ -955,10 +979,24 @@ static void GetTileDesc_Water(TileIndex tile, TileDesc *td)
 	switch (GetWaterTileType(tile)) {
 		case WATER_TILE_CLEAR:
 			switch (GetWaterClass(tile)) {
-				case WATER_CLASS_SEA:   td->str = STR_LAI_WATER_DESCRIPTION_WATER; break;
-				case WATER_CLASS_CANAL: td->str = STR_LAI_WATER_DESCRIPTION_CANAL; break;
-				case WATER_CLASS_RIVER: td->str = STR_LAI_WATER_DESCRIPTION_RIVER; break;
-				default: NOT_REACHED();
+				case WATER_CLASS_SEA:
+					td->str = STR_LAI_WATER_DESCRIPTION_WATER;
+					break;
+
+				case WATER_CLASS_CANAL:
+					if (HasTileCanalOnRiver(tile)) {
+						td->str = STR_LAI_WATER_DESCRIPTION_CANALISED_RIVER;
+					} else {
+						td->str = STR_LAI_WATER_DESCRIPTION_CANAL;
+					}
+					break;
+
+				case WATER_CLASS_RIVER:
+					td->str = STR_LAI_WATER_DESCRIPTION_RIVER;
+					break;
+
+				default:
+					NOT_REACHED();
 			}
 			break;
 		case WATER_TILE_COAST: td->str = STR_LAI_WATER_DESCRIPTION_COAST_OR_RIVERBANK; break;
@@ -1373,8 +1411,23 @@ static VehicleEnterTileStatus VehicleEnter_Water(Vehicle *v, TileIndex tile, int
 
 static CommandCost TerraformTile_Water(TileIndex tile, DoCommandFlag flags, int z_new, Slope tileh_new)
 {
+	bool no_err_message = _game_mode == GM_NORMAL && !_settings_game.construction.dynamite_river && !_cheats.magic_bulldozer.value;
+
 	/* Canals can't be terraformed */
-	if (IsWaterTile(tile) && IsCanal(tile)) return_cmd_error(STR_ERROR_MUST_DEMOLISH_CANAL_FIRST);
+	if (IsCanal(tile)) {
+		if (HasTileCanalOnRiver(tile) && no_err_message) {
+			return CMD_ERROR;
+		}
+		return_cmd_error(STR_ERROR_MUST_DEMOLISH_CANAL_FIRST);
+	}
+
+	/* Rivers can't be terraformed */
+	if (IsRiver(tile)) {
+		if (no_err_message) {
+			return CMD_ERROR;
+		}
+		return_cmd_error(STR_ERROR_MUST_CLEAR_RIVER_FIRST);
+	}
 
 	return Command<CMD_LANDSCAPE_CLEAR>::Do(flags, tile);
 }