(svn r20748) -Fix: overbuilding an object tile with sea under it with a canal didn't take the cost for clearing the sea into account

src/command_type.h

@@ -293,6 +293,7 @@ enum DoCommandFlag {
 	DC_AUTOREPLACE           = 0x080, ///< autoreplace/autorenew is in progress, this shall disable vehicle limits when building, and ignore certain restrictions when undoing things (like vehicle attach callback)
 	DC_ALL_TILES             = 0x100, ///< allow this command also on MP_VOID tiles
 	DC_NO_MODIFY_TOWN_RATING = 0x200, ///< do not change town rating
+	DC_FORCE_CLEAR_TILE      = 0x400, ///< do not only remove the object on the tile, but also clear any water left on it
 };
 DECLARE_ENUM_AS_BIT_SET(DoCommandFlag)
 

src/landscape.cpp

@@ -31,6 +31,7 @@
 #include "core/random_func.hpp"
 #include "object_base.h"
 #include "water_map.h"
+#include "economy_func.h"
 
 #include "table/strings.h"
 #include "table/sprites.h"
@@ -606,6 +607,13 @@ void ClearSnowLine()
  */
 CommandCost CmdLandscapeClear(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
+	CommandCost cost(EXPENSES_CONSTRUCTION);
+	bool do_clear = false;
+	if ((flags & DC_FORCE_CLEAR_TILE) && HasTileWaterClass(tile) && IsTileOnWater(tile)) {
+		if ((flags & DC_AUTO) && GetWaterClass(tile) == WATER_CLASS_CANAL) return_cmd_error(STR_ERROR_MUST_DEMOLISH_CANAL_FIRST);
+		do_clear = true;
+		cost.AddCost(GetWaterClass(tile) == WATER_CLASS_CANAL ? _price[PR_CLEAR_CANAL] : _price[PR_CLEAR_WATER]);
+	}
 	for (uint i = 0; i < _cleared_object_areas.Length(); i++) {
 		/* If this tile was the first tile which caused object destruction, always
 		 * pass it on to the tile_type_proc. That way multiple test runs and the exec run stay consistent. */
@@ -619,10 +627,12 @@ CommandCost CmdLandscapeClear(TileIndex tile, DoCommandFlag flags, uint32 p1, ui
 			if ((flags & DC_NO_WATER) && HasTileWaterClass(tile) && IsTileOnWater(tile)) {
 				return_cmd_error(STR_ERROR_CAN_T_BUILD_ON_WATER);
 			}
-			return CommandCost();
+			return cost;
 		}
 	}
-	return _tile_type_procs[GetTileType(tile)]->clear_tile_proc(tile, flags);
+	cost.AddCost(_tile_type_procs[GetTileType(tile)]->clear_tile_proc(tile, flags));
+	if (do_clear && (flags & DC_EXEC)) DoClearSquare(tile);
+	return cost;
 }
 
 /**

src/object_cmd.cpp

@@ -640,8 +640,6 @@ static CommandCost TerraformTile_Object(TileIndex tile, DoCommandFlag flags, uin
 {
 	ObjectType type = GetObjectType(tile);
 
-	if (GetWaterClass(tile) == WATER_CLASS_CANAL) return_cmd_error(STR_ERROR_MUST_DEMOLISH_CANAL_FIRST);
-
 	if (type == OBJECT_OWNED_LAND) {
 		/* Owned land remains unsold */
 		CommandCost ret = CheckTileOwnership(tile);

src/terraform_cmd.cpp

@@ -318,7 +318,7 @@ CommandCost CmdTerraformLand(TileIndex tile, DoCommandFlag flags, uint32 p1, uin
 			/* Check tiletype-specific things, and add extra-cost */
 			const bool curr_gen = _generating_world;
 			if (_game_mode == GM_EDITOR) _generating_world = true; // used to create green terraformed land
-			CommandCost cost = _tile_type_procs[GetTileType(tile)]->terraform_tile_proc(tile, flags | DC_AUTO, z_min * TILE_HEIGHT, tileh);
+			CommandCost cost = _tile_type_procs[GetTileType(tile)]->terraform_tile_proc(tile, flags | DC_AUTO | DC_FORCE_CLEAR_TILE, z_min * TILE_HEIGHT, tileh);
 			_generating_world = curr_gen;
 			if (cost.Failed()) {
 				_terraform_err_tile = tile;

src/water_cmd.cpp

@@ -332,7 +332,7 @@ CommandCost CmdBuildCanal(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32
 		/* can't make water of water! */
 		if (IsTileType(tile, MP_WATER) && (!IsTileOwner(tile, OWNER_WATER) || wc == WATER_CLASS_SEA)) continue;
 
-		ret = DoCommand(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
+		ret = DoCommand(tile, 0, 0, flags | DC_FORCE_CLEAR_TILE, CMD_LANDSCAPE_CLEAR);
 		if (ret.Failed()) return ret;
 		cost.AddCost(ret);