Add: Command to build an individual house on a specific tile.

src/command_type.h

@@ -283,6 +283,7 @@ enum Commands : uint16_t {
 	CMD_TOWN_SET_TEXT,                ///< set the custom text of a town
 	CMD_EXPAND_TOWN,                  ///< expand a town
 	CMD_DELETE_TOWN,                  ///< delete a town
+	CMD_PLACE_HOUSE,                  ///< place a house
 
 	CMD_ORDER_REFIT,                  ///< change the refit information of an order (for "goto depot" )
 	CMD_CLONE_ORDER,                  ///< clone (and share) an order

src/town_cmd.cpp

@@ -2665,6 +2665,39 @@ static bool CheckTownBuild2x2House(TileIndex *tile, Town *t, int maxz, bool nosl
 	return false;
 }
 
+/**
+ * Build a house at this tile.
+ * @param t The town the house will belong to.
+ * @param tile The tile to try building on.
+ * @param hs The @a HouseSpec of the house.
+ * @param house The @a HouseID of the house.
+ * @param random_bits The random data to be associated with the house.
+ */
+static void BuildTownHouse(Town *t, TileIndex tile, const HouseSpec *hs, HouseID house, uint8_t random_bits)
+{
+	/* build the house */
+	t->cache.num_houses++;
+
+	uint8_t construction_counter = 0;
+	uint8_t construction_stage = 0;
+
+	if (_generating_world || _game_mode == GM_EDITOR) {
+		uint32_t construction_random = Random();
+
+		construction_stage = TOWN_HOUSE_COMPLETED;
+		if (Chance16(1, 7)) construction_stage = GB(construction_random, 0, 2);
+
+		if (construction_stage == TOWN_HOUSE_COMPLETED) {
+			ChangePopulation(t, hs->population);
+		} else {
+			construction_counter = GB(construction_random, 2, 2);
+		}
+	}
+
+	MakeTownHouse(tile, t, construction_counter, construction_stage, house, random_bits);
+	UpdateTownRadius(t);
+	UpdateTownGrowthRate(t);
+}
 
 /**
  * Tries to build a house at this tile.
@@ -2784,31 +2817,10 @@ static bool TryBuildTownHouse(Town *t, TileIndex tile)
 			if (callback_res != CALLBACK_FAILED && !Convert8bitBooleanCallback(hs->grf_prop.grffile, CBID_HOUSE_ALLOW_CONSTRUCTION, callback_res)) continue;
 		}
 
-		/* build the house */
-		t->cache.num_houses++;
-
 		/* Special houses that there can be only one of. */
 		t->flags |= oneof;
 
-		uint8_t construction_counter = 0;
+		BuildTownHouse(t, tile, hs, house, random_bits);
-		uint8_t construction_stage = 0;
-
-		if (_generating_world || _game_mode == GM_EDITOR) {
-			uint32_t construction_random = Random();
-
-			construction_stage = TOWN_HOUSE_COMPLETED;
-			if (Chance16(1, 7)) construction_stage = GB(construction_random, 0, 2);
-
-			if (construction_stage == TOWN_HOUSE_COMPLETED) {
-				ChangePopulation(t, hs->population);
-			} else {
-				construction_counter = GB(construction_random, 2, 2);
-			}
-		}
-
-		MakeTownHouse(tile, t, construction_counter, construction_stage, house, random_bits);
-		UpdateTownRadius(t);
-		UpdateTownGrowthRate(t);
 
 		return true;
 	}
@@ -2816,6 +2828,56 @@ static bool TryBuildTownHouse(Town *t, TileIndex tile)
 	return false;
 }
 
+CommandCost CmdPlaceHouse(DoCommandFlag flags, TileIndex tile, HouseID house)
+{
+	if (_game_mode != GM_EDITOR) return CMD_ERROR;
+	if (Town::GetNumItems() == 0) return_cmd_error(STR_ERROR_MUST_FOUND_TOWN_FIRST);
+
+	if (static_cast<size_t>(house) >= HouseSpec::Specs().size()) return CMD_ERROR;
+	const HouseSpec *hs = HouseSpec::Get(house);
+	if (!hs->enabled) return CMD_ERROR;
+
+	if (TimerGameCalendar::year < hs->min_year || TimerGameCalendar::year > hs->max_year) return CMD_ERROR;
+
+	Town *t = ClosestTownFromTile(tile, UINT_MAX);
+
+	/* cannot build on these slopes... */
+	Slope slope = GetTileSlope(tile);
+	if (IsSteepSlope(slope)) return_cmd_error(STR_ERROR_LAND_SLOPED_IN_WRONG_DIRECTION);
+
+	/* building under a bridge? */
+	if (IsBridgeAbove(tile)) return_cmd_error(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);
+
+	/* can we clear the land? */
+	CommandCost cost = Command<CMD_LANDSCAPE_CLEAR>::Do(DC_AUTO | DC_NO_WATER, tile);
+	if (!cost.Succeeded()) return cost;
+
+	int maxz = GetTileMaxZ(tile);
+
+	/* Make sure there is no slope? */
+	bool noslope = (hs->building_flags & TILE_NOT_SLOPED) != 0;
+	if (noslope && slope != SLOPE_FLAT) return_cmd_error(STR_ERROR_FLAT_LAND_REQUIRED);
+
+	TileArea ta = tile;
+	if (hs->building_flags & TILE_SIZE_2x2) ta.Add(TileAddXY(tile, 1, 1));
+	if (hs->building_flags & TILE_SIZE_2x1) ta.Add(TileAddByDiagDir(tile, DIAGDIR_SW));
+	if (hs->building_flags & TILE_SIZE_1x2) ta.Add(TileAddByDiagDir(tile, DIAGDIR_SE));
+
+	/* Check additonal tiles covered by this house. */
+	for (const TileIndex &subtile : ta) {
+		cost = Command<CMD_LANDSCAPE_CLEAR>::Do(DC_AUTO | DC_NO_WATER, subtile);
+		if (!cost.Succeeded()) return cost;
+
+		if (!CheckBuildHouseSameZ(subtile, maxz, noslope)) return_cmd_error(STR_ERROR_LAND_SLOPED_IN_WRONG_DIRECTION);
+	}
+
+	if (flags & DC_EXEC) {
+		BuildTownHouse(t, tile, hs, house, Random());
+	}
+
+	return CommandCost();
+}
+
 /**
  * Update data structures when a house is removed
  * @param tile  Tile of the house

src/town_cmd.h

@@ -15,6 +15,7 @@
 #include "town_type.h"
 
 enum TownAcceptanceEffect : uint8_t;
+using HouseID = uint16_t;
 
 std::tuple<CommandCost, Money, TownID> CmdFoundTown(DoCommandFlag flags, TileIndex tile, TownSize size, bool city, TownLayout layout, bool random_location, uint32_t townnameparts, const std::string &text);
 CommandCost CmdRenameTown(DoCommandFlag flags, TownID town_id, const std::string &text);
@@ -25,6 +26,7 @@ CommandCost CmdTownCargoGoal(DoCommandFlag flags, TownID town_id, TownAcceptance
 CommandCost CmdTownSetText(DoCommandFlag flags, TownID town_id, const std::string &text);
 CommandCost CmdExpandTown(DoCommandFlag flags, TownID town_id, uint32_t grow_amount);
 CommandCost CmdDeleteTown(DoCommandFlag flags, TownID town_id);
+CommandCost CmdPlaceHouse(DoCommandFlag flags, TileIndex tile, HouseID house);
 
 DEF_CMD_TRAIT(CMD_FOUND_TOWN,       CmdFoundTown,      CMD_DEITY | CMD_NO_TEST,  CMDT_LANDSCAPE_CONSTRUCTION) // founding random town can fail only in exec run
 DEF_CMD_TRAIT(CMD_RENAME_TOWN,      CmdRenameTown,     CMD_DEITY | CMD_SERVER,   CMDT_OTHER_MANAGEMENT)
@@ -35,6 +37,7 @@ DEF_CMD_TRAIT(CMD_TOWN_RATING,      CmdTownRating,     CMD_DEITY,
 DEF_CMD_TRAIT(CMD_TOWN_SET_TEXT,    CmdTownSetText,    CMD_DEITY | CMD_STR_CTRL, CMDT_OTHER_MANAGEMENT)
 DEF_CMD_TRAIT(CMD_EXPAND_TOWN,      CmdExpandTown,     CMD_DEITY,                CMDT_LANDSCAPE_CONSTRUCTION)
 DEF_CMD_TRAIT(CMD_DELETE_TOWN,      CmdDeleteTown,     CMD_OFFLINE,              CMDT_LANDSCAPE_CONSTRUCTION)
+DEF_CMD_TRAIT(CMD_PLACE_HOUSE,      CmdPlaceHouse,     CMD_DEITY,                CMDT_OTHER_MANAGEMENT)
 
 CommandCallback CcFoundTown;
 void CcFoundRandomTown(Commands cmd, const CommandCost &result, Money, TownID town_id);