new file mode 100644
--- /dev/null
+++ b/src/terraform_gui.cpp
@@ -0,0 +1,285 @@
+/* $Id$ */
+
+#include "stdafx.h"
+#include "openttd.h"
+#include "bridge_map.h"
+#include "clear_map.h"
+#include "table/sprites.h"
+#include "table/strings.h"
+#include "functions.h"
+#include "player.h"
+#include "tile.h"
+#include "window.h"
+#include "gui.h"
+#include "viewport.h"
+#include "gfx.h"
+#include "sound.h"
+#include "command.h"
+#include "vehicle.h"
+#include "signs.h"
+#include "variables.h"
+
+void CcTerraform(bool success, TileIndex tile, uint32 p1, uint32 p2)
+{
+	if (success) {
+		SndPlayTileFx(SND_1F_SPLAT, tile);
+	} else {
+		SetRedErrorSquare(_terraform_err_tile);
+	}
+}
+
+
+/** Scenario editor command that generates desert areas */
+static void GenerateDesertArea(TileIndex end, TileIndex start)
+{
+	int size_x, size_y;
+	int sx = TileX(start);
+	int sy = TileY(start);
+	int ex = TileX(end);
+	int ey = TileY(end);
+
+	if (_game_mode != GM_EDITOR) return;
+
+	if (ex < sx) intswap(ex, sx);
+	if (ey < sy) intswap(ey, sy);
+	size_x = (ex - sx) + 1;
+	size_y = (ey - sy) + 1;
+
+	_generating_world = true;
+	BEGIN_TILE_LOOP(tile, size_x, size_y, TileXY(sx, sy)) {
+		if (GetTileType(tile) != MP_WATER) {
+			SetTropicZone(tile, (_ctrl_pressed) ? TROPICZONE_INVALID : TROPICZONE_DESERT);
+			DoCommandP(tile, 0, 0, NULL, CMD_LANDSCAPE_CLEAR);
+			MarkTileDirtyByTile(tile);
+		}
+	} END_TILE_LOOP(tile, size_x, size_y, 0);
+	_generating_world = false;
+}
+
+/** Scenario editor command that generates rocky areas */
+static void GenerateRockyArea(TileIndex end, TileIndex start)
+{
+	int size_x, size_y;
+	bool success = false;
+	int sx = TileX(start);
+	int sy = TileY(start);
+	int ex = TileX(end);
+	int ey = TileY(end);
+
+	if (_game_mode != GM_EDITOR) return;
+
+	if (ex < sx) intswap(ex, sx);
+	if (ey < sy) intswap(ey, sy);
+	size_x = (ex - sx) + 1;
+	size_y = (ey - sy) + 1;
+
+	BEGIN_TILE_LOOP(tile, size_x, size_y, TileXY(sx, sy)) {
+		switch (GetTileType(tile)) {
+			case MP_CLEAR:
+			case MP_TREES:
+				MakeClear(tile, CLEAR_ROCKS, 3);
+				break;
+
+			default: continue;
+		}
+		MarkTileDirtyByTile(tile);
+		success = true;
+	} END_TILE_LOOP(tile, size_x, size_y, 0);
+
+	if (success) SndPlayTileFx(SND_1F_SPLAT, end);
+}
+
+/**
+ * A central place to handle all X_AND_Y dragged GUI functions.
+ * @param e @WindowEvent variable holding in its higher bits (excluding the lower
+ * 4, since that defined the X_Y drag) the type of action to be performed
+ * @return Returns true if the action was found and handled, and false otherwise. This
+ * allows for additional implements that are more local. For example X_Y drag
+ * of convertrail which belongs in rail_gui.c and not terraform_gui.c
+ **/
+bool GUIPlaceProcDragXY(const WindowEvent *e)
+{
+	TileIndex start_tile = e->we.place.starttile;
+	TileIndex end_tile = e->we.place.tile;
+
+	switch (e->we.place.userdata >> 4) {
+	case GUI_PlaceProc_DemolishArea >> 4:
+		DoCommandP(end_tile, start_tile, 0, CcPlaySound10, CMD_CLEAR_AREA | CMD_MSG(STR_00B5_CAN_T_CLEAR_THIS_AREA));
+		break;
+	case GUI_PlaceProc_LevelArea >> 4:
+		DoCommandP(end_tile, start_tile, 0, CcPlaySound10, CMD_LEVEL_LAND | CMD_AUTO);
+		break;
+	case GUI_PlaceProc_RockyArea >> 4:
+		GenerateRockyArea(end_tile, start_tile);
+		break;
+	case GUI_PlaceProc_DesertArea >> 4:
+		GenerateDesertArea(end_tile, start_tile);
+		break;
+	case GUI_PlaceProc_WaterArea >> 4:
+		DoCommandP(end_tile, start_tile, _ctrl_pressed, CcBuildCanal, CMD_BUILD_CANAL | CMD_AUTO | CMD_MSG(STR_CANT_BUILD_CANALS));
+		break;
+	default: return false;
+	}
+
+	return true;
+}
+
+typedef void OnButtonClick(Window *w);
+
+static const uint16 _terraform_keycodes[] = {
+	'Q',
+	'W',
+	'E',
+	'D',
+	'U',
+	'I',
+	'O',
+};
+
+void PlaceProc_DemolishArea(TileIndex tile)
+{
+	VpStartPlaceSizing(tile, VPM_X_AND_Y | GUI_PlaceProc_DemolishArea);
+}
+
+static void PlaceProc_RaiseLand(TileIndex tile)
+{
+	DoCommandP(
+		tile, SLOPE_N, 1, CcTerraform,
+		CMD_TERRAFORM_LAND | CMD_AUTO | CMD_MSG(STR_0808_CAN_T_RAISE_LAND_HERE)
+	);
+}
+
+static void PlaceProc_LowerLand(TileIndex tile)
+{
+	DoCommandP(
+		tile, SLOPE_N, 0, CcTerraform,
+		CMD_TERRAFORM_LAND | CMD_AUTO | CMD_MSG(STR_0809_CAN_T_LOWER_LAND_HERE)
+	);
+}
+
+void PlaceProc_LevelLand(TileIndex tile)
+{
+	VpStartPlaceSizing(tile, VPM_X_AND_Y | GUI_PlaceProc_LevelArea);
+}
+
+static void TerraformClick_Lower(Window *w)
+{
+	HandlePlacePushButton(w, 4, ANIMCURSOR_LOWERLAND, 2, PlaceProc_LowerLand);
+}
+
+static void TerraformClick_Raise(Window *w)
+{
+	HandlePlacePushButton(w, 5, ANIMCURSOR_RAISELAND, 2, PlaceProc_RaiseLand);
+}
+
+static void TerraformClick_Level(Window *w)
+{
+	HandlePlacePushButton(w, 6, SPR_CURSOR_LEVEL_LAND, 2, PlaceProc_LevelLand);
+}
+
+static void TerraformClick_Dynamite(Window *w)
+{
+	HandlePlacePushButton(w, 7, ANIMCURSOR_DEMOLISH , 1, PlaceProc_DemolishArea);
+}
+
+static void TerraformClick_BuyLand(Window *w)
+{
+	HandlePlacePushButton(w, 8, SPR_CURSOR_BUY_LAND, 1, PlaceProc_BuyLand);
+}
+
+static void TerraformClick_Trees(Window *w)
+{
+	/* This button is NOT a place-push-button, so don't treat it as such */
+	ShowBuildTreesToolbar();
+}
+
+static void TerraformClick_PlaceSign(Window *w)
+{
+	HandlePlacePushButton(w, 10, SPR_CURSOR_SIGN, 1, PlaceProc_Sign);
+}
+
+static OnButtonClick * const _terraform_button_proc[] = {
+	TerraformClick_Lower,
+	TerraformClick_Raise,
+	TerraformClick_Level,
+	TerraformClick_Dynamite,
+	TerraformClick_BuyLand,
+	TerraformClick_Trees,
+	TerraformClick_PlaceSign,
+};
+
+static void TerraformToolbWndProc(Window *w, WindowEvent *e)
+{
+	switch (e->event) {
+	case WE_PAINT:
+		DrawWindowWidgets(w);
+		break;
+
+	case WE_CLICK:
+		if (e->we.click.widget >= 4) _terraform_button_proc[e->we.click.widget - 4](w);
+		break;
+
+	case WE_KEYPRESS: {
+		uint i;
+
+		for (i = 0; i != lengthof(_terraform_keycodes); i++) {
+			if (e->we.keypress.keycode == _terraform_keycodes[i]) {
+				e->we.keypress.cont = false;
+				_terraform_button_proc[i](w);
+				break;
+			}
+		}
+		break;
+	}
+
+	case WE_PLACE_OBJ:
+		_place_proc(e->we.place.tile);
+		return;
+
+	case WE_PLACE_DRAG:
+		VpSelectTilesWithMethod(e->we.place.pt.x, e->we.place.pt.y, e->we.place.userdata & 0xF);
+		break;
+
+	case WE_PLACE_MOUSEUP:
+		if (e->we.place.pt.x != -1 &&
+				(e->we.place.userdata & 0xF) == VPM_X_AND_Y) { // dragged actions
+			GUIPlaceProcDragXY(e);
+		}
+		break;
+
+	case WE_ABORT_PLACE_OBJ:
+		RaiseWindowButtons(w);
+		break;
+	}
+}
+
+static const Widget _terraform_widgets[] = {
+{ WWT_CLOSEBOX,   RESIZE_NONE,     7,   0,  10,   0,  13, STR_00C5,                STR_018B_CLOSE_WINDOW},
+{  WWT_CAPTION,   RESIZE_NONE,     7,  11, 145,   0,  13, STR_LANDSCAPING_TOOLBAR, STR_018C_WINDOW_TITLE_DRAG_THIS},
+{WWT_STICKYBOX,   RESIZE_NONE,     7, 146, 157,   0,  13, STR_NULL,                STR_STICKY_BUTTON},
+
+{    WWT_PANEL,   RESIZE_NONE,     7,  66,  69,  14,  35, 0x0,                    STR_NULL},
+{   WWT_IMGBTN,   RESIZE_NONE,     7,   0,  21,  14,  35, SPR_IMG_TERRAFORM_DOWN,  STR_018E_LOWER_A_CORNER_OF_LAND},
+{   WWT_IMGBTN,   RESIZE_NONE,     7,  22,  43,  14,  35, SPR_IMG_TERRAFORM_UP,    STR_018F_RAISE_A_CORNER_OF_LAND},
+{   WWT_IMGBTN,   RESIZE_NONE,     7,  44,  65,  14,  35, SPR_IMG_LEVEL_LAND,      STR_LEVEL_LAND_TOOLTIP},
+{   WWT_IMGBTN,   RESIZE_NONE,     7,  70,  91,  14,  35, SPR_IMG_DYNAMITE,        STR_018D_DEMOLISH_BUILDINGS_ETC},
+{   WWT_IMGBTN,   RESIZE_NONE,     7,  92, 113,  14,  35, SPR_IMG_BUY_LAND,        STR_0329_PURCHASE_LAND_FOR_FUTURE},
+{   WWT_IMGBTN,   RESIZE_NONE,     7, 114, 135,  14,  35, SPR_IMG_PLANTTREES,      STR_0185_PLANT_TREES_PLACE_SIGNS},
+{   WWT_IMGBTN,   RESIZE_NONE,     7, 136, 157,  14,  35, SPR_IMG_PLACE_SIGN,      STR_0289_PLACE_SIGN},
+
+{   WIDGETS_END},
+};
+
+static const WindowDesc _terraform_desc = {
+	WDP_ALIGN_TBR, 22+36, 158, 36,
+	WC_SCEN_LAND_GEN, 0,
+	WDF_STD_TOOLTIPS | WDF_STD_BTN | WDF_DEF_WIDGET | WDF_STICKY_BUTTON,
+	_terraform_widgets,
+	TerraformToolbWndProc
+};
+
+void ShowTerraformToolbar(void)
+{
+	if (!IsValidPlayer(_current_player)) return;
+	AllocateWindowDescFront(&_terraform_desc, 0);
+}