(svn r11773) -Codechange: move some non-clear-land functions from clear_cmd.cpp to a more correct location.

1 files changed, 411 insertions, 0 deletions

diff --git a/src/terraform_cmd.cpp b/src/terraform_cmd.cpp
new file mode 100644
index 000000000..138506231
--- /dev/null
+++ b/src/terraform_cmd.cpp
@@ -0,0 +1,411 @@
+/* $Id$ */
+
+/** @file terraform_cmd.cpp Commands related to terraforming. */
+
+#include "stdafx.h"
+#include "openttd.h"
+#include "strings_type.h"
+#include "table/strings.h"
+#include "command_func.h"
+#include "tile_map.h"
+#include "tunnel_map.h"
+#include "bridge_map.h"
+#include "variables.h"
+#include "functions.h"
+#include "economy_func.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;   ///< Referenced tile.
+	byte height;      ///< New TileHeight (height of north corner) of the tile.
+};
+
+struct TerraformerState {
+	int modheight_count;                                         ///< amount of entries in "modheight".
+	int tile_table_count;                                        ///< amount of entries in "tile_table".
+
+	/**
+	 * Dirty tiles, i.e.\ at least one corner changed.
+	 *
+	 * This array contains the tiles which are or will be marked as dirty.
+	 *
+	 * @ingroup dirty
+	 */
+	TileIndex tile_table[TERRAFORMER_TILE_TABLE_SIZE];
+	TerraformerHeightMod modheight[TERRAFORMER_MODHEIGHT_SIZE];  ///< Height modifications.
+};
+
+TileIndex _terraform_err_tile;
+
+/**
+ * Gets the TileHeight (height of north corner) of a tile as of current terraforming progress.
+ *
+ * @param ts TerraformerState.
+ * @param tile Tile.
+ * @return TileHeight.
+ */
+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.
+ * @ingroup dirty
+ */
+static void TerraformAddDirtyTile(TerraformerState *ts, TileIndex tile)
+{
+	int count;
+	TileIndex *t;
+
+	count = ts->tile_table_count;
+
+	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.
+ * @ingroup dirty
+ */
+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);
+}
+
+/**
+ * Terraform the north corner of a tile to a specific height.
+ *
+ * @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());
+
+	/* Check range of destination height */
+	if (height < 0) return_cmd_error(STR_1003_ALREADY_AT_SEA_LEVEL);
+	if (height > MAX_TILE_HEIGHT) return_cmd_error(STR_1004_TOO_HIGH);
+
+	/*
+	 * 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.).
+	 * In this case the terraforming should fail. (Don't know why.)
+	 */
+	if (height == TerraformGetHeightOfTile(ts, tile)) return CMD_ERROR;
+
+	/* Check "too close to edge of map" */
+	uint x = TileX(tile);
+	uint y = TileY(tile);
+	if ((x <= 1) || (y <= 1) || (x >= MapMaxX() - 1) || (y >= MapMaxY() - 1)) {
+		/*
+		 * Determine a sensible error tile
+		 * Note: If x and y are both zero this will disable the error tile. (Tile 0 cannot be highlighted :( )
+		 */
+		if ((x == 1) && (y != 0)) x = 0;
+		if ((y == 1) && (x != 0)) y = 0;
+		_terraform_err_tile = TileXY(x, y);
+		return_cmd_error(STR_0002_TOO_CLOSE_TO_EDGE_OF_MAP);
+	}
+
+	/* Mark incident tiles, that are involved in the terraforming */
+	TerraformAddDirtyTileAround(ts, tile);
+
+	/* Store the height modification */
+	TerraformSetHeightOfTile(ts, tile, height);
+
+	/* Increment cost */
+	total_cost.AddCost(_price.terraform);
+
+	/* Recurse to neighboured corners if height difference is larger than 1 */
+	{
+		const TileIndexDiffC *ttm;
+
+		static const TileIndexDiffC _terraform_tilepos[] = {
+			{ 1,  0}, // move to tile in SE
+			{-2,  0}, // undo last move, and move to tile in NW
+			{ 1,  1}, // undo last move, and move to tile in SW
+			{ 0, -2}  // undo last move, and move to tile in NE
+		};
+
+		for (ttm = _terraform_tilepos; ttm != endof(_terraform_tilepos); ttm++) {
+			tile += ToTileIndexDiff(*ttm);
+
+			/* Get TileHeight of neighboured tile as of current terraform progress */
+			int r = TerraformGetHeightOfTile(ts, tile);
+			int height_diff = height - r;
+
+			/* 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);
+				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 (SLOPE_xxx)
+ * @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;
+	CommandCost total_cost = CommandCost();
+	int direction = (p2 != 0 ? 1 : -1);
+
+	SET_EXPENSES_TYPE(EXPENSES_CONSTRUCTION);
+
+	_terraform_err_tile = 0;
+
+	ts.modheight_count = ts.tile_table_count = 0;
+
+	/* Make an extra check for map-bounds cause we add tiles to the originating tile */
+	if (tile + TileDiffXY(1, 1) >= MapSize()) return CMD_ERROR;
+
+	/* Compute the costs and the terraforming result in a model of the landscape */
+	if ((p1 & SLOPE_W) != 0) {
+		TileIndex t = tile + TileDiffXY(1, 0);
+		CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
+		if (CmdFailed(cost)) return cost;
+		total_cost.AddCost(cost);
+	}
+
+	if ((p1 & SLOPE_S) != 0) {
+		TileIndex t = tile + TileDiffXY(1, 1);
+		CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
+		if (CmdFailed(cost)) return cost;
+		total_cost.AddCost(cost);
+	}
+
+	if ((p1 & SLOPE_E) != 0) {
+		TileIndex t = tile + TileDiffXY(0, 1);
+		CommandCost cost = TerraformTileHeight(&ts, t, TileHeight(t) + direction);
+		if (CmdFailed(cost)) return cost;
+		total_cost.AddCost(cost);
+	}
+
+	if ((p1 & SLOPE_N) != 0) {
+		TileIndex t = tile + TileDiffXY(0, 0);
+		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 */
+	{
+		int count;
+		TileIndex *ti = ts.tile_table;
+
+		for (count = ts.tile_table_count; count != 0; count--, ti++) {
+			TileIndex tile = *ti;
+
+			/* Find new heights of tile corners */
+			uint z_N = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(0, 0));
+			uint z_W = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(1, 0));
+			uint z_S = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(1, 1));
+			uint z_E = TerraformGetHeightOfTile(&ts, tile + TileDiffXY(0, 1));
+
+			/* Find min and max height of tile */
+			uint z_min = min(min(z_N, z_W), min(z_S, z_E));
+			uint z_max = max(max(z_N, z_W), max(z_S, z_E));
+
+			/* 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 | DC_AUTO, z_min * TILE_HEIGHT, (Slope) tileh);
+			if (CmdFailed(cost)) {
+				_terraform_err_tile = tile;
+				return cost;
+			}
+			total_cost.AddCost(cost);
+		}
+	}
+
+	if (flags & DC_EXEC) {
+		/* 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);
+			}
+		}
+
+		/* finally mark the dirty tiles dirty */
+		{
+			int count;
+			TileIndex *ti = ts.tile_table;
+			for (count = ts.tile_table_count; count != 0; count--, ti++) {
+				MarkTileDirtyByTile(*ti);
+			}
+		}
+	}
+	return total_cost;
+}
+
+
+/** Levels a selected (rectangle) area of land
+ * @param tile end tile of area-drag
+ * @param flags for this command type
+ * @param p1 start tile of area drag
+ * @param p2 height difference; eg raise (+1), lower (-1) or level (0)
+ * @return  error or cost of terraforming
+ */
+CommandCost CmdLevelLand(TileIndex tile, uint32 flags, uint32 p1, uint32 p2)
+{
+	int size_x, size_y;
+	int ex;
+	int ey;
+	int sx, sy;
+	uint h, oldh, curh;
+	CommandCost money;
+	CommandCost ret;
+	CommandCost cost;
+
+	if (p1 >= MapSize()) return CMD_ERROR;
+
+	SET_EXPENSES_TYPE(EXPENSES_CONSTRUCTION);
+
+	/* remember level height */
+	oldh = TileHeight(p1);
+
+	/* compute new height */
+	h = oldh + p2;
+
+	/* Check range of destination height */
+	if (h > MAX_TILE_HEIGHT) return_cmd_error((oldh == 0) ? STR_1003_ALREADY_AT_SEA_LEVEL : STR_1004_TOO_HIGH);
+
+	/* make sure sx,sy are smaller than ex,ey */
+	ex = TileX(tile);
+	ey = TileY(tile);
+	sx = TileX(p1);
+	sy = TileY(p1);
+	if (ex < sx) Swap(ex, sx);
+	if (ey < sy) Swap(ey, sy);
+	tile = TileXY(sx, sy);
+
+	size_x = ex - sx + 1;
+	size_y = ey - sy + 1;
+
+	money.AddCost(GetAvailableMoneyForCommand());
+
+	BEGIN_TILE_LOOP(tile2, size_x, size_y, tile) {
+		curh = TileHeight(tile2);
+		while (curh != h) {
+			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, SLOPE_N, (curh > h) ? 0 : 1, flags, CMD_TERRAFORM_LAND);
+			}
+
+			cost.AddCost(ret);
+			curh += (curh > h) ? -1 : 1;
+		}
+	} END_TILE_LOOP(tile2, size_x, size_y, tile)
+
+	return (cost.GetCost() == 0) ? CMD_ERROR : cost;
+}