openttd-ottdgrfs: comparison src/clear

equal deleted inserted replaced

-:a4ad48192617
+:7eb395287b3d
 #include "unmovable_map.h"
 #include "genworld.h"
 #include "industry.h"
 #include "water_map.h"
+/*
+* In one terraforming command all four corners of a initial tile can be raised/lowered (though this is not available to the player).
+* The maximal amount of height modifications is archieved when raising a complete flat land from sea level to MAX_TILE_HEIGHT or vice versa.
+* This affects all corners with a manhatten distance smaller than MAX_TILE_HEIGHT to one of the initial 4 corners.
+* Their maximal amount is computed to 4 * \sum_{i=1}^{h_max} i  =  2 * h_max * (h_max + 1).
+*/
+static const int TERRAFORMER_MODHEIGHT_SIZE = 2 * MAX_TILE_HEIGHT * (MAX_TILE_HEIGHT + 1);
+/*
+* The maximal amount of affected tiles (i.e. the tiles that incident with one of the corners above, is computed similiar to
+* 1 + 4 * \sum_{i=1}^{h_max} (i+1)  =  1 + 2 * h_max + (h_max + 3).
+*/
+static const int TERRAFORMER_TILE_TABLE_SIZE = 1 + 2 * MAX_TILE_HEIGHT * (MAX_TILE_HEIGHT + 3);
 struct TerraformerHeightMod {
-	TileIndex tile;
+	TileIndex tile;   ///< Referenced tile.
-	byte height;
+	byte height;      ///< New TileHeight (height of north corner) of the tile.
 };
 struct TerraformerState {
-	int height[4];
+	int modheight_count;                                         ///< amount of entries in "modheight".
-	uint32 flags;
+	int tile_table_count;                                        ///< amount of entries in "tile_table".
-	int direction;
+	TileIndex tile_table[TERRAFORMER_TILE_TABLE_SIZE];           ///< Dirty tiles, i.e. at least one corner changed.
-	int modheight_count;
+	TerraformerHeightMod modheight[TERRAFORMER_MODHEIGHT_SIZE];  ///< Height modifications.
-	int tile_table_count;
-	CommandCost cost;
-	TileIndex *tile_table;
-	TerraformerHeightMod *modheight;
 };
-static int TerraformAllowTileProcess(TerraformerState *ts, TileIndex tile)
+/**
-{
+* Gets the TileHeight (height of north corner) of a tile as of current terraforming progress.
-	TileIndex *t;
+*
-	int count;
+* @param ts TerraformerState.
+* @param tile Tile.
-	if (TileX(tile) == MapMaxX() || TileY(tile) == MapMaxY()) return -1;
+* @return TileHeight.
+*/
-	t = ts->tile_table;
-	for (count = ts->tile_table_count; count != 0; count--, t++) {
-		if (*t == tile) return 0;
-	}
-	return 1;
-}
 static int TerraformGetHeightOfTile(TerraformerState *ts, TileIndex tile)
 {
 	TerraformerHeightMod *mod = ts->modheight;
 	int count;
 	for (count = ts->modheight_count; count != 0; count--, mod++) {
 		if (mod->tile == tile) return mod->height;
 	}
+	/* TileHeight unchanged so far, read value from map. */
 	return TileHeight(tile);
 }
+/**
+* Stores the TileHeight (height of north corner) of a tile in a TerraformerState.
+*
+* @param ts TerraformerState.
+* @param tile Tile.
+* @param height New TileHeight.
+*/
+static void TerraformSetHeightOfTile(TerraformerState *ts, TileIndex tile, int height)
+{
+	/* Find tile in the "modheight" table.
+	 * Note: In a normal user-terraform command the tile will not be found in the "modheight" table.
+	 *       But during house- or industry-construction multiple corners can be terraformed at once. */
+	TerraformerHeightMod *mod = ts->modheight;
+	int count = ts->modheight_count;
+	while ((count > 0) && (mod->tile != tile)) {
+		mod++;
+		count--;
+	}
+	/* New entry? */
+	if (count == 0) {
+		assert(ts->modheight_count < TERRAFORMER_MODHEIGHT_SIZE);
+		ts->modheight_count++;
+	}
+	/* Finally store the new value */
+	mod->tile = tile;
+	mod->height = (byte)height;
+}
+/**
+* Adds a tile to the "tile_table" in a TerraformerState.
+*
+* @param ts TerraformerState.
+* @param tile Tile.
+*/
 static void TerraformAddDirtyTile(TerraformerState *ts, TileIndex tile)
 {
 	int count;
 	TileIndex *t;
 	count = ts->tile_table_count;
-	if (count >= 625) return;
 	for (t = ts->tile_table; count != 0; count--, t++) {
 		if (*t == tile) return;
 	}
+	assert(ts->tile_table_count < TERRAFORMER_TILE_TABLE_SIZE);
 	ts->tile_table[ts->tile_table_count++] = tile;
 }
+/**
+* Adds all tiles that incident with the north corner of a specific tile to the "tile_table" in a TerraformerState.
+*
+* @param ts TerraformerState.
+* @param tile Tile.
+*/
 static void TerraformAddDirtyTileAround(TerraformerState *ts, TileIndex tile)
 {
 	TerraformAddDirtyTile(ts, tile + TileDiffXY( 0, -1));
 	TerraformAddDirtyTile(ts, tile + TileDiffXY(-1, -1));
 	TerraformAddDirtyTile(ts, tile + TileDiffXY(-1,  0));
 	TerraformAddDirtyTile(ts, tile);
 }
-static int TerraformProc(TerraformerState *ts, TileIndex tile, int mode)
+/**
-{
+* Terraform the north corner of a tile to a specific height.
-	int r;
+*
-	CommandCost ret;
+* @param ts TerraformerState.
+* @param tile Tile.
+* @param height Aimed height.
+* @param return Error code or cost.
+*/
+static CommandCost TerraformTileHeight(TerraformerState *ts, TileIndex tile, int height)
+{
+	CommandCost total_cost = CommandCost();
 	assert(tile < MapSize());
-	r = TerraformAllowTileProcess(ts, tile);
+	/* Check range of destination height */
-	if (r <= 0) return r;
+	if (height < 0) return_cmd_error(STR_1003_ALREADY_AT_SEA_LEVEL);
+	if (height > MAX_TILE_HEIGHT) return_cmd_error(STR_1004_TOO_HIGH);
-	if (IsTileType(tile, MP_RAILWAY)) {
-		static const TrackBits safe_track[] = { TRACK_BIT_LOWER, TRACK_BIT_LEFT, TRACK_BIT_UPPER, TRACK_BIT_RIGHT };
+	/*
-		static const Slope unsafe_slope[] = { SLOPE_S, SLOPE_W, SLOPE_N, SLOPE_E };
+	 * Check if the terraforming has any effect.
+	 * This can only be true, if multiple corners of the start-tile are terraformed (i.e. the terraforming is done by towns/industries etc.).
-		Slope tileh;
+	 * In this case the terraforming should fail. (Don't know why.)
-		uint z;
+	 */
+	if (height == TerraformGetHeightOfTile(ts, tile)) return CMD_ERROR;
-		/* Nothing could be built at the steep slope - this avoids a bug
-		 * when you have a single diagonal track in one corner on a
+	/* Check "too close to edge of map" */
-		 * basement and then you raise/lower the other corner. */
+	uint x = TileX(tile);
-		tileh = GetTileSlope(tile, &z);
+	uint y = TileY(tile);
-		if (tileh == unsafe_slope[mode] ||
+	if ((x <= 1) || (y <= 1) || (x >= MapMaxX() - 1) || (y >= MapMaxY() - 1)) {
-				tileh == (SLOPE_STEEP | ComplementSlope(unsafe_slope[mode]))) {
+		/*
-			_terraform_err_tile = tile;
+		 * Determine a sensible error tile
-			_error_message = STR_1008_MUST_REMOVE_RAILROAD_TRACK;
+		 * Note: If x and y are both zero this will disable the error tile. (Tile 0 cannot be highlighted :( )
-			return -1;
+		 */
-		}
+		if ((x == 1) && (y != 0)) x = 0;
+		if ((y == 1) && (x != 0)) y = 0;
-		/* If we have a single diagonal track there, the other side of
+		_terraform_err_tile = TileXY(x, y);
-		 * tile can be terraformed. */
+		return_cmd_error(STR_0002_TOO_CLOSE_TO_EDGE_OF_MAP);
-		if (IsPlainRailTile(tile) && GetTrackBits(tile) == safe_track[mode]) {
+	}
-			/* If terraforming downwards prevent damaging a potential tunnel below.
-			 * This check is only necessary for flat tiles, because if the tile is
+	/* Mark incident tiles, that are involved in the terraforming */
-			 * non-flat, then the corner opposing the rail is raised. Only this corner
+	TerraformAddDirtyTileAround(ts, tile);
-			 * can be lowered and this is a safe action
-			 */
+	/* Store the height modification */
-			if (tileh == SLOPE_FLAT &&
+	TerraformSetHeightOfTile(ts, tile, height);
-					ts->direction == -1 &&
-					IsTunnelInWay(tile, z - TILE_HEIGHT)) {
+	/* Increment cost */
-				_terraform_err_tile = tile;
+	total_cost.AddCost(_price.terraform);
-				_error_message = STR_1002_EXCAVATION_WOULD_DAMAGE;
-				return -1;
+	/* Recurse to neighboured corners if height difference is larger than 1 */
-			}
-			return 0;
-		}
-	}
-	/* Canals can't be terraformed */
-	if (IsClearWaterTile(tile) && IsCanal(tile)) {
-		_terraform_err_tile = tile;
-		_error_message = STR_MUST_DEMOLISH_CANAL_FIRST;
-		return -1;
-	}
-	ret = DoCommand(tile, 0, 0, ts->flags & ~DC_EXEC, CMD_LANDSCAPE_CLEAR);
-	if (CmdFailed(ret)) {
-		_terraform_err_tile = tile;
-		return -1;
-	}
-	ts->cost.AddCost(ret.GetCost());
-	if (ts->tile_table_count >= 625) return -1;
-	ts->tile_table[ts->tile_table_count++] = tile;
-	return 0;
-}
-static bool TerraformTileHeight(TerraformerState *ts, TileIndex tile, int height)
-{
-	int nh;
-	TerraformerHeightMod *mod;
-	int count;
-	assert(tile < MapSize());
-	if (height < 0) {
-		_error_message = STR_1003_ALREADY_AT_SEA_LEVEL;
-		return false;
-	}
-	_error_message = STR_1004_TOO_HIGH;
-	if (height > MAX_TILE_HEIGHT) return false;
-	nh = TerraformGetHeightOfTile(ts, tile);
-	if (nh < 0 || height == nh) return false;
-	if (TerraformProc(ts, tile, 0) < 0) return false;
-	if (TerraformProc(ts, tile + TileDiffXY( 0, -1), 1) < 0) return false;
-	if (TerraformProc(ts, tile + TileDiffXY(-1, -1), 2) < 0) return false;
-	if (TerraformProc(ts, tile + TileDiffXY(-1,  0), 3) < 0) return false;
-	mod = ts->modheight;
-	count = ts->modheight_count;
-	for (;;) {
-		if (count == 0) {
-			if (ts->modheight_count >= 576) return false;
-			ts->modheight_count++;
-			break;
-		}
-		if (mod->tile == tile) break;
-		mod++;
-		count--;
-	}
-	mod->tile = tile;
-	mod->height = (byte)height;
-	ts->cost.AddCost(_price.terraform);
 	{
-		int direction = ts->direction, r;
 		const TileIndexDiffC *ttm;
 		static const TileIndexDiffC _terraform_tilepos[] = {
-			{ 1,  0},
+			{ 1,  0}, // move to tile in SE
-			{-2,  0},
+			{-2,  0}, // undo last move, and move to tile in NW
-			{ 1,  1},
+			{ 1,  1}, // undo last move, and move to tile in SW
-			{ 0, -2}
+			{ 0, -2}  // undo last move, and move to tile in NE
 		};
 		for (ttm = _terraform_tilepos; ttm != endof(_terraform_tilepos); ttm++) {
 			tile += ToTileIndexDiff(*ttm);
-			r = TerraformGetHeightOfTile(ts, tile);
+			/* Get TileHeight of neighboured tile as of current terraform progress */
-			if (r != height && r - direction != height && r + direction != height) {
+			int r = TerraformGetHeightOfTile(ts, tile);
-				if (!TerraformTileHeight(ts, tile, r + direction))
+			int height_diff = height - r;
-					return false;
-			}
+			/* Is the height difference to the neighboured corner greater than 1? */
-		}
+			if (abs(height_diff) > 1) {
-	}
+				/* Terraform the neighboured corner. The resulting height difference should be 1. */
+				height_diff += (height_diff < 0 ? 1 : -1);
-	return true;
+				CommandCost cost = TerraformTileHeight(ts, tile, r + height_diff);
+				if (CmdFailed(cost)) return cost;
+				total_cost.AddCost(cost);
+			}
+		}
+	}
+	return total_cost;
 }
 /** Terraform land
 * @param tile tile to terraform
 * @param flags for this command type
-* @param p1 corners to terraform.
+* @param p1 corners to terraform (SLOPE_xxx)
-* @param p2 direction; eg up or down
+* @param p2 direction; eg up (non-zero) or down (zero)
 * @return error or cost of terraforming
 */
 CommandCost CmdTerraformLand(TileIndex tile, uint32 flags, uint32 p1, uint32 p2)
 {
 	TerraformerState ts;
-	TileIndex t;
+	CommandCost total_cost = CommandCost();
-	int direction;
+	int direction = (p2 != 0 ? 1 : -1);
-	TerraformerHeightMod modheight_data[576];
-	TileIndex tile_table_data[625];
 	SET_EXPENSES_TYPE(EXPENSES_CONSTRUCTION);
 	_terraform_err_tile = 0;
-	ts.direction = direction = p2 ? 1 : -1;
-	ts.flags = flags;
 	ts.modheight_count = ts.tile_table_count = 0;
-	ts.cost = CommandCost();
-	ts.modheight = modheight_data;
-	ts.tile_table = tile_table_data;
 	/* Make an extra check for map-bounds cause we add tiles to the originating tile */
 	if (tile + TileDiffXY(1, 1) >= MapSize()) return CMD_ERROR;
-	if (p1 & 1) {
+	/* Compute the costs and the terraforming result in a model of the landscape */
-		t = tile + TileDiffXY(1, 0);
+	if ((p1 & SLOPE_W) != 0) {
-		if (!TerraformTileHeight(&ts, t, TileHeight(t) + direction)) {
+		TileIndex t = tile + TileDiffXY(1, 0);
-			return CMD_ERROR;
+		CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
-		}
+		if (CmdFailed(cost)) return cost;
-	}
+		total_cost.AddCost(cost);
+	}
-	if (p1 & 2) {
-		t = tile + TileDiffXY(1, 1);
+	if ((p1 & SLOPE_S) != 0) {
-		if (!TerraformTileHeight(&ts, t, TileHeight(t) + direction)) {
+		TileIndex t = tile + TileDiffXY(1, 1);
-			return CMD_ERROR;
+		CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
-		}
+		if (CmdFailed(cost)) return cost;
-	}
+		total_cost.AddCost(cost);
+	}
-	if (p1 & 4) {
-		t = tile + TileDiffXY(0, 1);
+	if ((p1 & SLOPE_E) != 0) {
-		if (!TerraformTileHeight(&ts, t, TileHeight(t) + direction)) {
+		TileIndex t = tile + TileDiffXY(0, 1);
-			return CMD_ERROR;
+		CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
-		}
+		if (CmdFailed(cost)) return cost;
-	}
+		total_cost.AddCost(cost);
+	}
-	if (p1 & 8) {
-		t = tile + TileDiffXY(0, 0);
+	if ((p1 & SLOPE_N) != 0) {
-		if (!TerraformTileHeight(&ts, t, TileHeight(t) + direction)) {
+		TileIndex t = tile + TileDiffXY(0, 0);
-			return CMD_ERROR;
+		CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
-		}
+		if (CmdFailed(cost)) return cost;
-	}
+		total_cost.AddCost(cost);
+	}
+	/* Check if the terraforming is valid wrt. tunnels, bridges and objects on the surface */
 	{
-		/* Check if tunnel would take damage */
 		int count;
 		TileIndex *ti = ts.tile_table;
 		for (count = ts.tile_table_count; count != 0; count--, ti++) {
 			TileIndex tile = *ti;
-			uint z_min = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(0, 0));
+			/* Find new heights of tile corners */
-			uint z_max = z_min;
+			uint z_N = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(0, 0));
-			uint t = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(1, 0));
+			uint z_W = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(1, 0));
-			z_min = min(z_min, t);
+			uint z_S = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(1, 1));
-			z_max = max(z_max, t);
+			uint z_E = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(0, 1));
-			t = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(1, 1));
-			z_min = min(z_min, t);
+			/* Find min and max height of tile */
-			z_max = max(z_max, t);
+			uint z_min = min(min(z_N, z_W), min(z_S, z_E));
-			t = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(0, 1));
+			uint z_max = max(max(z_N, z_W), max(z_S, z_E));
-			z_min = min(z_min, t);
-			z_max = max(z_max, t);
+			/* Compute tile slope */
+			uint tileh = (z_max > z_min + 1 ? SLOPE_STEEP : SLOPE_FLAT);
+			if (z_W > z_min) tileh += SLOPE_W;
+			if (z_S > z_min) tileh += SLOPE_S;
+			if (z_E > z_min) tileh += SLOPE_E;
+			if (z_N > z_min) tileh += SLOPE_N;
+			/* Check if bridge would take damage */
 			if (direction == 1 && MayHaveBridgeAbove(tile) && IsBridgeAbove(tile) &&
 					GetBridgeHeight(GetSouthernBridgeEnd(tile)) <= z_max * TILE_HEIGHT) {
+				_terraform_err_tile = tile; // highlight the tile under the bridge
 				return_cmd_error(STR_5007_MUST_DEMOLISH_BRIDGE_FIRST);
 			}
+			/* Check if tunnel would take damage */
 			if (direction == -1 && IsTunnelInWay(tile, z_min * TILE_HEIGHT)) {
+				_terraform_err_tile = tile; // highlight the tile above the tunnel
 				return_cmd_error(STR_1002_EXCAVATION_WOULD_DAMAGE);
 			}
+			/* Check tiletype-specific things, and add extra-cost */
+			CommandCost cost = _tile_type_procs[GetTileType(tile)]->terraform_tile_proc(tile, flags, z_min * TILE_HEIGHT, (Slope) tileh);
+			if (CmdFailed(cost)) {
+				_terraform_err_tile = tile;
+				return cost;
+			}
+			total_cost.AddCost(cost);
 		}
 	}
 	if (flags & DC_EXEC) {
-		/* Clear the landscape at the tiles */
-		{
-			int count;
-			TileIndex *ti = ts.tile_table;
-			for (count = ts.tile_table_count; count != 0; count--, ti++) {
-				DoCommand(*ti, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
-			}
-		}
 		/* change the height */
 		{
 			int count;
 			TerraformerHeightMod *mod;
 			mod = ts.modheight;
 			for (count = ts.modheight_count; count != 0; count--, mod++) {
 				TileIndex til = mod->tile;
 				SetTileHeight(til, mod->height);
-				TerraformAddDirtyTileAround(&ts, til);
 			}
 		}
 		/* finally mark the dirty tiles dirty */
 		{
 			for (count = ts.tile_table_count; count != 0; count--, ti++) {
 				MarkTileDirtyByTile(*ti);
 			}
 		}
 	}
-	return ts.cost;
+	return total_cost;
 }
 /** Levels a selected (rectangle) area of land
 * @param tile end tile of area-drag
 	money.AddCost(GetAvailableMoneyForCommand());
 	BEGIN_TILE_LOOP(tile2, size_x, size_y, tile) {
 		curh = TileHeight(tile2);
 		while (curh != h) {
-			ret = DoCommand(tile2, 8, (curh > h) ? 0 : 1, flags & ~DC_EXEC, CMD_TERRAFORM_LAND);
+			ret = DoCommand(tile2, SLOPE_N, (curh > h) ? 0 : 1, flags & ~DC_EXEC, CMD_TERRAFORM_LAND);
 			if (CmdFailed(ret)) break;
 			if (flags & DC_EXEC) {
 				money.AddCost(-ret.GetCost());
 				if (money.GetCost() < 0) {
 					_additional_cash_required = ret.GetCost();
 					return cost;
 				}
-				DoCommand(tile2, 8, (curh > h) ? 0 : 1, flags, CMD_TERRAFORM_LAND);
+				DoCommand(tile2, SLOPE_N, (curh > h) ? 0 : 1, flags, CMD_TERRAFORM_LAND);
 			}
 			cost.AddCost(ret);
 			curh += (curh > h) ? -1 : 1;
 		}
 CommandCost CmdPurchaseLandArea(TileIndex tile, uint32 flags, uint32 p1, uint32 p2)
 {
 	CommandCost cost;
 	SET_EXPENSES_TYPE(EXPENSES_CONSTRUCTION);
-	if (!EnsureNoVehicle(tile)) return CMD_ERROR;
 	if (IsOwnedLandTile(tile) && IsTileOwner(tile, _current_player)) {
 		return_cmd_error(STR_5807_YOU_ALREADY_OWN_IT);
 	}
 }
 void InitializeClearLand()
 {
 	_opt.snow_line = _patches.snow_line_height * TILE_HEIGHT;
+}
+static CommandCost TerraformTile_Clear(TileIndex tile, uint32 flags, uint z_new, Slope tileh_new)
+{
+	return DoCommand(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
 }
 extern const TileTypeProcs _tile_type_clear_procs = {
 	DrawTile_Clear,           ///< draw_tile_proc
 	GetSlopeZ_Clear,          ///< get_slope_z_proc
 	TileLoop_Clear,           ///< tile_loop_clear
 	ChangeTileOwner_Clear,    ///< change_tile_owner_clear
 	NULL,                     ///< get_produced_cargo_proc
 	NULL,                     ///< vehicle_enter_tile_proc
 	GetFoundation_Clear,      ///< get_foundation_proc
+	TerraformTile_Clear,      ///< terraform_tile_proc
 };

branch	NewGRF_ports
changeset 6868	7eb395287b3d
parent 6743	cabfaa4a0295
child 6870	ca3fd1fbe311