(svn r2136) - Fix: [ 1174313 ] terrain hotkeys nonfunctional in scenario editor (D,Q,W,E,R,T,Y,U fltr)

- Fix: 'L' no longer opens ingame terraform bar in scenario editor bar, but the land generator one
- Feature: [ 1095110 ] Create Lake and draggable Create Desert tools (initial implementation GoneWacko), also added sticky buttons to land generator and town generator
- CodeChange: moved around some of the draggable tools, demystifying them
- CodeChange: change CmdBuildCanal to allow for XANDY dragging not only X or Y (only scenario editor)
- CodeChange: add some more enums to sprites.
- TODO: merge most of the ingame and scenario editor land terraform code. This can only be done after OnClickButton function is changed so it also includes the backreference to the widget being clicked, postponed to after 0.4.0

8 files changed, 298 insertions, 203 deletions

diff --git a/dock_gui.c b/dock_gui.c
index ae7ee3b46..33de7e516 100644
--- a/dock_gui.c
+++ b/dock_gui.c
@@ -47,7 +47,7 @@ static void PlaceDocks_Buoy(uint tile)
 
 static void PlaceDocks_DemolishArea(uint tile)
 {
-	VpStartPlaceSizing(tile, VPM_X_AND_Y);
+	VpStartPlaceSizing(tile, VPM_X_AND_Y | GUI_PlaceProc_DemolishArea);
 }
 
 static void PlaceDocks_BuildCanal(uint tile)
@@ -145,9 +145,9 @@ static void BuildDocksToolbWndProc(Window *w, WindowEvent *e)
 
 	case WE_PLACE_MOUSEUP:
 		if (e->click.pt.x != -1) {
-			if (e->place.userdata == VPM_X_AND_Y)
-				DoCommandP(e->place.tile, e->place.starttile, 0, CcPlaySound10, CMD_CLEAR_AREA | CMD_MSG(STR_00B5_CAN_T_CLEAR_THIS_AREA));
-			else if(e->place.userdata == VPM_X_OR_Y)
+			if ((e->place.userdata & 0xF) == VPM_X_AND_Y) { // dragged actions
+				GUIPlaceProcDragXY(e);
+			} else if(e->place.userdata == VPM_X_OR_Y)
 				DoCommandP(e->place.tile, e->place.starttile, 0, CcBuildCanal, CMD_BUILD_CANAL | CMD_AUTO | CMD_MSG(STR_CANT_BUILD_CANALS));
 		}
 		break;
@@ -182,8 +182,8 @@ static const Widget _build_docks_toolb_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_9801_DOCK_CONSTRUCTION,	STR_018C_WINDOW_TITLE_DRAG_THIS},
 {  WWT_STICKYBOX,   RESIZE_NONE,     7,   146,   157,     0,    13, 0x0,                         STR_STICKY_BUTTON},
-{      WWT_PANEL,   RESIZE_NONE,     7,     0,    21,    14,    35, SPR_OPENTTD_BASE+65,					STR_BUILD_CANALS_TIP},
-{      WWT_PANEL,   RESIZE_NONE,     7,    22,    43,    14,    35, SPR_CANALS_BASE+69,					STR_BUILD_LOCKS_TIP},
+{      WWT_PANEL,   RESIZE_NONE,     7,     0,    21,    14,    35, SPR_IMG_BUILD_CANAL,					STR_BUILD_CANALS_TIP},
+{      WWT_PANEL,   RESIZE_NONE,     7,    22,    43,    14,    35, SPR_IMG_BUILD_LOCK,					STR_BUILD_LOCKS_TIP},
 
 {      WWT_PANEL,   RESIZE_NONE,     7,    44,    47,    14,    35, 0x0,													STR_NULL},
 
diff --git a/gui.h b/gui.h
index 868662144..03655a5ac 100644
--- a/gui.h
+++ b/gui.h
@@ -6,6 +6,8 @@
 /* main_gui.c */
 void SetupColorsAndInitialWindow(void);
 void CcPlaySound10(bool success, uint tile, uint32 p1, uint32 p2);
+void CcBuildCanal(bool success, uint tile, uint32 p1, uint32 p2);
+void CcTerraform(bool success, uint tile, uint32 p1, uint32 p2);
 
 /* settings_gui.c */
 void ShowGameOptions(void);
@@ -57,14 +59,23 @@ void ShowBuildAirToolbar(void);
 void ShowPlayerAircraft(int player, int station);
 
 /* terraform_gui.c */
+void ShowTerraformToolbar(void);
+
 void PlaceProc_DemolishArea(uint tile);
 void PlaceProc_LowerLand(uint tile);
 void PlaceProc_RaiseLand(uint tile);
 void PlaceProc_LevelLand(uint tile);
-void ShowTerraformToolbar(void);
+bool GUIPlaceProcDragXY(const WindowEvent *we);
+
+enum { // max 32 - 4 = 28 types
+	GUI_PlaceProc_DemolishArea    = 0 << 4,
+	GUI_PlaceProc_LevelArea       = 1 << 4,
+	GUI_PlaceProc_DesertArea      = 2 << 4,
+	GUI_PlaceProc_WaterArea       = 3 << 4,
+	GUI_PlaceProc_ConvertRailArea = 4 << 4
+};
 
 /* misc_gui.c */
-
 void PlaceLandBlockInfo(void);
 void ShowAboutWindow(void);
 void ShowBuildTreesToolbar(void);
diff --git a/lang/english.txt b/lang/english.txt
index d871d4583..5b309f281 100644
--- a/lang/english.txt
+++ b/lang/english.txt
@@ -694,6 +694,7 @@ STR_028C_PLACE_ROCKY_AREAS_ON_LANDSCAPE				:{BLACK}Place rocky areas on landscap
 STR_028D_PLACE_LIGHTHOUSE					:{BLACK}Place lighthouse
 STR_028E_PLACE_TRANSMITTER					:{BLACK}Place transmitter
 STR_028F_DEFINE_DESERT_AREA					:{BLACK}Define desert area
+STR_CREATE_LAKE							:{BLACK}Define water area, will flood its surroundings if at sea level
 STR_0290_DELETE							:{BLACK}Delete
 STR_0291_DELETE_THIS_TOWN_COMPLETELY				:{BLACK}Delete this town completely
 STR_0292_SAVE_SCENARIO						:Save scenario
diff --git a/main_gui.c b/main_gui.c
index 8f0a7f247..5155d8b98 100644
--- a/main_gui.c
+++ b/main_gui.c
@@ -49,8 +49,6 @@ extern void GenerateWorld(int mode, uint log_x, uint log_y);
 extern void GenerateIndustries(void);
 extern void GenerateTowns(void);
 
-extern void CcTerraform(bool success, uint tile, uint32 p1, uint32 p2);
-
 void HandleOnEditTextCancel(void)
 {
 	switch(_rename_what) {
@@ -1145,6 +1143,15 @@ static void AskResetLandscape(uint mode)
 	AllocateWindowDescFront(&_ask_reset_landscape_desc, mode);
 }
 
+// TODO - Incorporate into game itself to allow for ingame raising/lowering of
+// larger chunks at the same time OR remove altogether, as we have 'level land' ?
+/**
+ * Raise/Lower a bigger chunk of land at the same time in the editor. When
+ * raising get the lowest point, when lowering the highest point, and set all
+ * tiles in the selection to that height.
+ * @param tile The top-left tile where the terraforming will start
+ * @param mode 1 for raising, 0 for lowering land
+ */
 static void CommonRaiseLowerBigLand(uint tile, int mode)
 {
 	int size;
@@ -1152,9 +1159,7 @@ static void CommonRaiseLowerBigLand(uint tile, int mode)
 
 	_error_message_2 = mode ? STR_0808_CAN_T_RAISE_LAND_HERE : STR_0809_CAN_T_LOWER_LAND_HERE;
 
-	_generating_world = true;
-
-//	tile = TILE_FROM_XY(TileX(tile) * 16 + _tile_fract_coords.x + 8, TileY(tile) * 16 + _tile_fract_coords.y + 8);
+	_generating_world = true; // used to create green terraformed land
 
 	if (_terraform_size == 1) {
 		DoCommandP(tile, 8, (uint32)mode, CcTerraform, CMD_TERRAFORM_LAND | CMD_AUTO | CMD_MSG(_error_message_2));
@@ -1165,7 +1170,7 @@ static void CommonRaiseLowerBigLand(uint tile, int mode)
 		assert(size != 0);
 		if (mode != 0) {
 			/* Raise land */
-			h = 15;
+			h = 15; // XXX - max height
 			BEGIN_TILE_LOOP(tile2, size, size, tile)
 				h = min(h, TileHeight(tile2));
 			END_TILE_LOOP(tile2, size, size, tile)
@@ -1197,20 +1202,6 @@ static void PlaceProc_LowerBigLand(uint tile)
 	CommonRaiseLowerBigLand(tile, 0);
 }
 
-//void CcDemolish(bool success, uint tile, uint32 p1, uint32 p2)
-//{
-//	if (success) {
-		//SndPlayTileFx(0x10, tile);
-		//CreateEffectVehicleAbove(TileX(tile) * 16 + 8, TileY(tile) * 16 + 8, 2, EV_DEMOLISH);
-//	}
-//}
-
-//void PlaceProc_Demolish(uint tile)
-//{
-//	DoCommandP(tile, 0, 0, CcDemolish, CMD_LANDSCAPE_CLEAR | CMD_MSG(STR_00B5_CAN_T_CLEAR_THIS_AREA));
-//}
-
-
 static void PlaceProc_RockyArea(uint tile)
 {
 	if (!IsTileType(tile, MP_CLEAR) && !IsTileType(tile, MP_TREES))
@@ -1244,27 +1235,34 @@ static void PlaceProc_Transmitter(uint tile)
 	SndPlayTileFx(SND_1F_SPLAT, tile);
 }
 
-static void PlaceProc_Desert(uint tile)
+static void PlaceProc_DesertArea(TileIndex tile)
 {
-	SetMapExtraBits(tile, GetMapExtraBits(tile) == 1 ? 0 : 1);
+	VpStartPlaceSizing(tile, VPM_X_AND_Y | GUI_PlaceProc_DesertArea);
+}
+
+static void PlaceProc_WaterArea(TileIndex tile)
+{
+	VpStartPlaceSizing(tile, VPM_X_AND_Y | GUI_PlaceProc_WaterArea);
 }
 
 static const Widget _scen_edit_land_gen_widgets[] = {
-{    WWT_TEXTBTN,   RESIZE_NONE,     7,     0,    10,     0,    13, STR_00C5,	STR_018B_CLOSE_WINDOW},
-{    WWT_CAPTION,   RESIZE_NONE,     7,    11,   153,     0,    13, STR_0223_LAND_GENERATION,STR_018C_WINDOW_TITLE_DRAG_THIS},
-{     WWT_IMGBTN,   RESIZE_NONE,     7,     0,   153,    14,    99, 0x0,				STR_NULL},
-{     WWT_IMGBTN,   RESIZE_NONE,    14,    22,    43,    14,    35, 0x2B6,			STR_018F_RAISE_A_CORNER_OF_LAND},
-{     WWT_IMGBTN,   RESIZE_NONE,    14,    44,    65,    14,    35, 0x2B7,			STR_018E_LOWER_A_CORNER_OF_LAND},
-{     WWT_IMGBTN,   RESIZE_NONE,    14,     0,    21,    14,    35, 0x2BF,			STR_018D_DEMOLISH_BUILDINGS_ETC},
-{    WWT_TEXTBTN,   RESIZE_NONE,    14,   125,   135,    43,    54, STR_0224,	STR_0228_INCREASE_SIZE_OF_LAND_AREA},
-{    WWT_TEXTBTN,   RESIZE_NONE,    14,   125,   135,    56,    67, STR_0225,	STR_0229_DECREASE_SIZE_OF_LAND_AREA},
-{    WWT_TEXTBTN,   RESIZE_NONE,    14,    20,   135,    75,    86, STR_0226_RANDOM_LAND,		STR_022A_GENERATE_RANDOM_LAND},
-{    WWT_TEXTBTN,   RESIZE_NONE,    14,    20,   135,    88,    99, STR_0227_RESET_LAND,			STR_022B_RESET_LANDSCAPE},
-
-{     WWT_IMGBTN,   RESIZE_NONE,    14,    88,   109,    14,    35, 0xFF4,			STR_028C_PLACE_ROCKY_AREAS_ON_LANDSCAPE},
-{     WWT_IMGBTN,   RESIZE_NONE,    14,   110,   131,    14,    35, 0xFF5,			STR_028D_PLACE_LIGHTHOUSE},
-{     WWT_IMGBTN,   RESIZE_NONE,    14,   132,   153,    14,    35, 0xFF6,			STR_028E_PLACE_TRANSMITTER},
-{     WWT_IMGBTN,   RESIZE_NONE,    14,    66,    87,    14,    35, SPR_OPENTTD_BASE+68,			STR_LEVEL_LAND_TOOLTIP},
+{   WWT_TEXTBTN,   RESIZE_NONE,     7,     0,    10,     0,    13, STR_00C5,                  STR_018B_CLOSE_WINDOW},
+{   WWT_CAPTION,   RESIZE_NONE,     7,    11,   169,     0,    13, STR_0223_LAND_GENERATION,  STR_018C_WINDOW_TITLE_DRAG_THIS},
+{ WWT_STICKYBOX,   RESIZE_NONE,     7,   170,   181,     0,    13, STR_NULL,                  STR_STICKY_BUTTON},
+{    WWT_IMGBTN,   RESIZE_NONE,     7,     0,   181,    14,   101, STR_NULL,                  STR_NULL},
+
+{    WWT_IMGBTN,   RESIZE_NONE,    14,     2,    23,    14,    35, SPR_IMG_DYNAMITE,          STR_018D_DEMOLISH_BUILDINGS_ETC},
+{    WWT_IMGBTN,   RESIZE_NONE,    14,    24,    45,    14,    35, SPR_IMG_TERRAFORM_UP,      STR_018F_RAISE_A_CORNER_OF_LAND},
+{    WWT_IMGBTN,   RESIZE_NONE,    14,    46,    67,    14,    35, SPR_IMG_TERRAFORM_DOWN,    STR_018E_LOWER_A_CORNER_OF_LAND},
+{    WWT_IMGBTN,   RESIZE_NONE,    14,    68,    89,    14,    35, SPR_IMG_LEVEL_LAND,        STR_LEVEL_LAND_TOOLTIP},
+{    WWT_IMGBTN,   RESIZE_NONE,    14,    90,   111,    14,    35, SPR_IMG_BUILD_CANAL,       STR_CREATE_LAKE},
+{    WWT_IMGBTN,   RESIZE_NONE,    14,   112,   134,    14,    35, SPR_IMG_ROCKS,             STR_028C_PLACE_ROCKY_AREAS_ON_LANDSCAPE},
+{    WWT_IMGBTN,   RESIZE_NONE,    14,   135,   157,    14,    35, SPR_IMG_LIGHTHOUSE_DESERT, STR_NULL}, // XXX - dynamic
+{    WWT_IMGBTN,   RESIZE_NONE,    14,   158,   179,    14,    35, SPR_IMG_TRANSMITTER,       STR_028E_PLACE_TRANSMITTER},
+{   WWT_TEXTBTN,   RESIZE_NONE,    14,   139,   149,    43,    54, STR_0224,                  STR_0228_INCREASE_SIZE_OF_LAND_AREA},
+{   WWT_TEXTBTN,   RESIZE_NONE,    14,   139,   149,    56,    67, STR_0225,                  STR_0229_DECREASE_SIZE_OF_LAND_AREA},
+{   WWT_TEXTBTN,   RESIZE_NONE,    14,    34,   149,    75,    86, STR_0226_RANDOM_LAND,      STR_022A_GENERATE_RANDOM_LAND},
+{   WWT_TEXTBTN,   RESIZE_NONE,    14,    34,   149,    88,    99, STR_0227_RESET_LAND,       STR_022B_RESET_LANDSCAPE},
 {   WIDGETS_END},
 };
 
@@ -1279,12 +1277,80 @@ static const int8 _multi_terraform_coords[][2] = {
 	{-28,  0},{-24, -2},{-20, -4},{-16, -6},{-12, -8},{ -8,-10},{ -4,-12},{  0,-14},{  4,-12},{  8,-10},{ 12, -8},{ 16, -6},{ 20, -4},{ 24, -2},{ 28,  0},
 };
 
+// TODO - Merge with terraform_gui.c (move there) after I have cooled down at its braindeadness
+// and changed OnButtonClick to include the widget as well in the function decleration. Post 0.4.0 - Darkvater
+static void EditorTerraformClick_Dynamite(Window *w)
+{
+	HandlePlacePushButton(w, 4, ANIMCURSOR_DEMOLISH, 1, PlaceProc_DemolishArea);
+}
+
+static void EditorTerraformClick_LowerBigLand(Window *w)
+{
+	HandlePlacePushButton(w, 5, ANIMCURSOR_LOWERLAND, 2, PlaceProc_LowerBigLand);
+}
+
+static void EditorTerraformClick_RaiseBigLand(Window *w)
+{
+	HandlePlacePushButton(w, 6, ANIMCURSOR_RAISELAND, 2, PlaceProc_RaiseBigLand);
+}
+
+static void EditorTerraformClick_LevelLand(Window *w)
+{
+	HandlePlacePushButton(w, 7, SPR_CURSOR_LEVEL_LAND, 2, PlaceProc_LevelLand);
+}
+
+static void EditorTerraformClick_WaterArea(Window *w)
+{
+	HandlePlacePushButton(w, 8, SPR_CURSOR_CANAL, 1, PlaceProc_WaterArea);
+}
+
+static void EditorTerraformClick_RockyArea(Window *w)
+{
+	HandlePlacePushButton(w, 9, SPR_CURSOR_ROCKY_AREA, 1, PlaceProc_RockyArea);
+}
+
+static void EditorTerraformClick_DesertLightHouse(Window *w)
+{
+	HandlePlacePushButton(w, 10, SPR_CURSOR_LIGHTHOUSE, 1, (_opt.landscape == LT_DESERT) ? PlaceProc_DesertArea : PlaceProc_LightHouse);
+}
+
+static void EditorTerraformClick_Transmitter(Window *w)
+{
+	HandlePlacePushButton(w, 11, SPR_CURSOR_TRANSMITTER, 1, PlaceProc_Transmitter);
+}
+
+static const uint16 _editor_terraform_keycodes[] = {
+	'D',
+	'Q',
+	'W',
+	'E',
+	'R',
+	'T',
+	'Y',
+	'U'
+};
+
+typedef void OnButtonClick(Window *w);
+static OnButtonClick * const _editor_terraform_button_proc[] = {
+	EditorTerraformClick_Dynamite,
+	EditorTerraformClick_LowerBigLand,
+	EditorTerraformClick_RaiseBigLand,
+	EditorTerraformClick_LevelLand,
+	EditorTerraformClick_WaterArea,
+	EditorTerraformClick_RockyArea,
+	EditorTerraformClick_DesertLightHouse,
+	EditorTerraformClick_Transmitter
+};
+
 static void ScenEditLandGenWndProc(Window *w, WindowEvent *e)
 {
-	switch(e->event) {
+	switch (e->event) {
+	case WE_CREATE:
+		// XXX - lighthouse button is widget 10!! Don't forget when changing
+		w->widget[10].tooltips = (_opt.landscape == LT_DESERT) ? STR_028F_DEFINE_DESERT_AREA : STR_028D_PLACE_LIGHTHOUSE;
+		break;
+
 	case WE_PAINT:
-		// XXX - lighthouse button is widget 11!! Don't forget when changing
-		w->widget[11].tooltips = (_opt.landscape == LT_DESERT) ? STR_028F_DEFINE_DESERT_AREA : STR_028D_PLACE_LIGHTHOUSE;
 		DrawWindowWidgets(w);
 
 		{
@@ -1293,93 +1359,71 @@ static void ScenEditLandGenWndProc(Window *w, WindowEvent *e)
 
 			assert(n != 0);
 			do {
-				DrawSprite(0xFEF, 77 + coords[0], 55 + coords[1]);
+				DrawSprite(SPR_WHITE_POINT, 77 + coords[0], 55 + coords[1]);
 				coords += 2;
 			} while (--n);
 		}
 
-		if (_thd.window_class == WC_SCEN_LAND_GEN && (w->click_state&(1<<3|1<<4))) {
+		if (w->click_state & ( 1 << 5 | 1 << 6)) // change area-size if raise/lower corner is selected
 			SetTileSelectSize(_terraform_size, _terraform_size);
-		}
+
 		break;
+
+	case WE_KEYPRESS: {
+		int i;
+
+		for (i = 0; i != lengthof(_editor_terraform_keycodes); i++) {
+			if (e->keypress.keycode == _editor_terraform_keycodes[i]) {
+				e->keypress.cont = false;
+				_editor_terraform_button_proc[i](w);
+				break;
+			}
+		}
+	} break;
+
 	case WE_CLICK:
 		switch (e->click.widget) {
-		case 3: /* raise corner */
-			HandlePlacePushButton(w, 3, ANIMCURSOR_RAISELAND, 2, PlaceProc_RaiseBigLand);
+		case 4: case 5: case 6: case 7: case 8: case 9: case 10: case 11:
+			_editor_terraform_button_proc[e->click.widget - 4](w);
 			break;
-		case 4: /* lower corner */
-			HandlePlacePushButton(w, 4, ANIMCURSOR_LOWERLAND, 2, PlaceProc_LowerBigLand);
-			break;
-		case 5: /* demolish */
-			HandlePlacePushButton(w, 5, ANIMCURSOR_DEMOLISH, 1, PlaceProc_DemolishArea);
-			break;
-		{
-			int size;
-		case 6: /* increase terraform size */
-			HandleButtonClick(w, 6);
-			size = 1;
-			goto terraform_size_common;
-		case 7: /* decrease terraform size */
-			HandleButtonClick(w, 7);
-			size = -1;
-terraform_size_common:;
+		case 12: case 13: { /* Increase/Decrease terraform size */
+			int size = (e->click.widget == 12) ? 1 : -1;
+			HandleButtonClick(w, e->click.widget);
 			size += _terraform_size;
-			if (!IS_INT_INSIDE(size, 1, 8+1))
-				return;
+
+			if (!IS_INT_INSIDE(size, 1, 8 + 1))	return;
 			_terraform_size = size;
+
 			SndPlayFx(SND_15_BEEP);
 			SetWindowDirty(w);
-			break;
-		}
-
-		case 8: /* gen random land */
-			HandleButtonClick(w, 8);
+		} break;
+		case 14: /* gen random land */
+			HandleButtonClick(w, 14);
 			AskResetLandscape(0);
 			break;
-
-		case 9: /* reset landscape */
-			HandleButtonClick(w,9);
+		case 15: /* reset landscape */
+			HandleButtonClick(w,15);
 			AskResetLandscape(1);
 			break;
-
-		case 10: /* place rocky areas */
-			HandlePlacePushButton(w, 10, 0xFF7, 1, PlaceProc_RockyArea);
-			break;
-
-		case 11: /* place lighthouse */
-			HandlePlacePushButton(w, 11, 0xFF8, 1, _opt.landscape == LT_DESERT ? PlaceProc_Desert : PlaceProc_LightHouse);
-			break;
-
-		case 12: /* place transmitter */
-			HandlePlacePushButton(w, 12, 0xFF9, 1, PlaceProc_Transmitter);
-			break;
-
-		case 13: /* level Land */
-			HandlePlacePushButton(w, 13, SPR_OPENTTD_BASE+69, 2, PlaceProc_LevelLand);
-			break;
 		}
 		break;
+
 	case WE_TIMEOUT:
-		UnclickSomeWindowButtons(w, ~(1<<3 | 1<<4 | 1<<5 | 1<<10 | 1<<11 | 1<<12));
+		UnclickSomeWindowButtons(w, ~(1<<4 | 1<<5 | 1<<6 | 1<<7 | 1<<8 | 1<<9 | 1<<10 | 1<<11));
 		break;
 	case WE_PLACE_OBJ:
 		_place_proc(e->place.tile);
 		break;
-	case WE_PLACE_DRAG: {
+	case WE_PLACE_DRAG:
 		VpSelectTilesWithMethod(e->place.pt.x, e->place.pt.y, e->place.userdata & 0xF);
-		return;
-	}
+		break;
+
 	case WE_PLACE_MOUSEUP:
 		if (e->click.pt.x != -1) {
-			uint start_tile = e->place.starttile;
-			uint end_tile = e->place.tile;
-			if (e->place.userdata == VPM_X_AND_Y) {
-				DoCommandP(end_tile, start_tile, 0, CcPlaySound10, CMD_CLEAR_AREA | CMD_MSG(STR_00B5_CAN_T_CLEAR_THIS_AREA));
-			} else if (e->place.userdata == (VPM_X_AND_Y | (2<<4))) {
-				DoCommandP(end_tile, start_tile, 0, CcPlaySound10, CMD_LEVEL_LAND | CMD_AUTO);
-			}
+			if ((e->place.userdata & 0xF) == VPM_X_AND_Y) // dragged actions
+				GUIPlaceProcDragXY(e);
 		}
-	break;
+		break;
 
 	case WE_ABORT_PLACE_OBJ:
 		w->click_state = 0;
@@ -1389,19 +1433,24 @@ terraform_size_common:;
 }
 
 static const WindowDesc _scen_edit_land_gen_desc = {
-	-1,-1, 154, 100,
+	-1,-1, 182, 102,
 	WC_SCEN_LAND_GEN,0,
-	WDF_STD_TOOLTIPS | WDF_STD_BTN | WDF_DEF_WIDGET,
+	WDF_STD_TOOLTIPS | WDF_STD_BTN | WDF_DEF_WIDGET | WDF_STICKY_BUTTON,
 	_scen_edit_land_gen_widgets,
 	ScenEditLandGenWndProc,
 };
 
+static inline void ShowEditorTerraformToolBar(void)
+{
+	AllocateWindowDescFront(&_scen_edit_land_gen_desc, 0);
+}
+
 static void ToolbarScenGenLand(Window *w)
 {
 	HandleButtonClick(w, 11);
 	SndPlayFx(SND_15_BEEP);
 
-	AllocateWindowDescFront(&_scen_edit_land_gen_desc, 0);
+	ShowEditorTerraformToolBar();
 }
 
 void CcBuildTown(bool success, uint tile, uint32 p1, uint32 p2)
@@ -1419,15 +1468,16 @@ static void PlaceProc_Town(uint tile)
 
 
 static const Widget _scen_edit_town_gen_widgets[] = {
-{    WWT_TEXTBTN,   RESIZE_NONE,     7,     0,    10,     0,    13, STR_00C5,									STR_018B_CLOSE_WINDOW},
-{    WWT_CAPTION,   RESIZE_NONE,     7,    11,   159,     0,    13, STR_0233_TOWN_GENERATION,	STR_018C_WINDOW_TITLE_DRAG_THIS},
-{     WWT_IMGBTN,   RESIZE_NONE,     7,     0,   159,    14,    81, 0x0,												STR_NULL},
-{    WWT_TEXTBTN,   RESIZE_NONE,    14,     2,   157,    16,    27, STR_0234_NEW_TOWN,					STR_0235_CONSTRUCT_NEW_TOWN},
-{    WWT_TEXTBTN,   RESIZE_NONE,    14,     2,   157,    29,    40, STR_023D_RANDOM_TOWN,			STR_023E_BUILD_TOWN_IN_RANDOM_LOCATION},
-{    WWT_TEXTBTN,   RESIZE_NONE,    14,     2,   157,    42,    53, STR_MANY_RANDOM_TOWNS,			STR_RANDOM_TOWNS_TIP},
-{    WWT_TEXTBTN,   RESIZE_NONE,    14,     2,    53,    68,    79, STR_02A1_SMALL,						STR_02A4_SELECT_TOWN_SIZE},
-{    WWT_TEXTBTN,   RESIZE_NONE,    14,    54,   105,    68,    79, STR_02A2_MEDIUM,						STR_02A4_SELECT_TOWN_SIZE},
-{    WWT_TEXTBTN,   RESIZE_NONE,    14,   106,   157,    68,    79, STR_02A3_LARGE,						STR_02A4_SELECT_TOWN_SIZE},
+{    WWT_TEXTBTN,   RESIZE_NONE,     7,     0,    10,     0,    13, STR_00C5,                 STR_018B_CLOSE_WINDOW},
+{    WWT_CAPTION,   RESIZE_NONE,     7,    11,   147,     0,    13, STR_0233_TOWN_GENERATION, STR_018C_WINDOW_TITLE_DRAG_THIS},
+{  WWT_STICKYBOX,   RESIZE_NONE,     7,   148,   159,     0,    13, 0x0,                      STR_STICKY_BUTTON},
+{     WWT_IMGBTN,   RESIZE_NONE,     7,     0,   159,    14,    81, 0x0,                      STR_NULL},
+{    WWT_TEXTBTN,   RESIZE_NONE,    14,     2,   157,    16,    27, STR_0234_NEW_TOWN,        STR_0235_CONSTRUCT_NEW_TOWN},
+{    WWT_TEXTBTN,   RESIZE_NONE,    14,     2,   157,    29,    40, STR_023D_RANDOM_TOWN,     STR_023E_BUILD_TOWN_IN_RANDOM_LOCATION},
+{    WWT_TEXTBTN,   RESIZE_NONE,    14,     2,   157,    42,    53, STR_MANY_RANDOM_TOWNS,    STR_RANDOM_TOWNS_TIP},
+{    WWT_TEXTBTN,   RESIZE_NONE,    14,     2,    53,    68,    79, STR_02A1_SMALL,           STR_02A4_SELECT_TOWN_SIZE},
+{    WWT_TEXTBTN,   RESIZE_NONE,    14,    54,   105,    68,    79, STR_02A2_MEDIUM,          STR_02A4_SELECT_TOWN_SIZE},
+{    WWT_TEXTBTN,   RESIZE_NONE,    14,   106,   157,    68,    79, STR_02A3_LARGE,           STR_02A4_SELECT_TOWN_SIZE},
 {   WIDGETS_END},
 };
 
@@ -1435,20 +1485,20 @@ static void ScenEditTownGenWndProc(Window *w, WindowEvent *e)
 {
 	switch(e->event) {
 	case WE_PAINT:
-		w->click_state = (w->click_state & ~(1<<6 | 1<<7 | 1<<8) ) | (1 << (_new_town_size + 6));
+		w->click_state = (w->click_state & ~(1<<7 | 1<<8 | 1<<9) ) | (1 << (_new_town_size + 7));
 		DrawWindowWidgets(w);
 		DrawStringCentered(80, 56, STR_02A5_TOWN_SIZE, 0);
 		break;
 
 	case WE_CLICK:
-		switch(e->click.widget) {
-		case 3: /* new town */
-			HandlePlacePushButton(w, 3, 0xFF0, 1, PlaceProc_Town);
+		switch (e->click.widget) {
+		case 4: /* new town */
+			HandlePlacePushButton(w, 4, SPR_CURSOR_TOWN, 1, PlaceProc_Town);
 			break;
-		case 4: {/* random town */
+		case 5: {/* random town */
 			Town *t;
 
-			HandleButtonClick(w, 4);
+			HandleButtonClick(w, 5);
 			_generating_world = true;
 			t = CreateRandomTown(20);
 			_generating_world = false;
@@ -1456,8 +1506,8 @@ static void ScenEditTownGenWndProc(Window *w, WindowEvent *e)
 				ScrollMainWindowToTile(t->xy);
 			break;
 		}
-		case 5: {/* many random towns */
-			HandleButtonClick(w, 5);
+		case 6: {/* many random towns */
+			HandleButtonClick(w, 6);
 			_generating_world = true;
 			_game_mode = GM_NORMAL; // little hack to avoid towns of the same size
 			GenerateTowns();
@@ -1466,15 +1516,15 @@ static void ScenEditTownGenWndProc(Window *w, WindowEvent *e)
 			break;
 		}
 
-		case 6: case 7: case 8:
-			_new_town_size = e->click.widget - 6;
+		case 7: case 8: case 9:
+			_new_town_size = e->click.widget - 7;
 			SetWindowDirty(w);
 			break;
 		}
 		break;
 
 	case WE_TIMEOUT:
-		UnclickSomeWindowButtons(w, 1<<4 | 1<<5);
+		UnclickSomeWindowButtons(w, 1<<5 | 1<<6);
 		break;
 	case WE_PLACE_OBJ:
 		_place_proc(e->place.tile);
@@ -1489,7 +1539,7 @@ static void ScenEditTownGenWndProc(Window *w, WindowEvent *e)
 static const WindowDesc _scen_edit_town_gen_desc = {
 	-1,-1, 160, 82,
 	WC_SCEN_TOWN_GEN,0,
-	WDF_STD_TOOLTIPS | WDF_STD_BTN | WDF_DEF_WIDGET,
+	WDF_STD_TOOLTIPS | WDF_STD_BTN | WDF_DEF_WIDGET | WDF_STICKY_BUTTON,
 	_scen_edit_town_gen_widgets,
 	ScenEditTownGenWndProc,
 };
@@ -2308,7 +2358,10 @@ static void MainWindowWndProc(Window *w, WindowEvent *e) {
 			break;
 
 		case 'L':
-			ShowTerraformToolbar();
+  		if (_game_mode == GM_EDITOR) {
+  			ShowEditorTerraformToolBar();
+  		} else
+  			ShowTerraformToolbar();
 			break;
 
 		case 'X':
diff --git a/rail_gui.c b/rail_gui.c
index f1b522958..093a2df1f 100644
--- a/rail_gui.c
+++ b/rail_gui.c
@@ -203,7 +203,7 @@ void PlaceProc_BuyLand(uint tile)
 
 static void PlaceRail_ConvertRail(uint tile)
 {
-	VpStartPlaceSizing(tile, VPM_X_AND_Y | (1<<4));
+	VpStartPlaceSizing(tile, VPM_X_AND_Y | GUI_PlaceProc_ConvertRailArea);
 }
 
 static void PlaceRail_AutoSignals(uint tile)
@@ -436,8 +436,8 @@ static void BuildRailToolbWndProc(Window *w, WindowEvent *e)
 
 	case WE_PLACE_MOUSEUP:
 		if (e->click.pt.x != -1) {
-			uint start_tile = e->place.starttile;
-			uint end_tile = e->place.tile;
+			TileIndex start_tile = e->place.starttile;
+			TileIndex end_tile = e->place.tile;
 
 			if (e->place.userdata == VPM_X_OR_Y) {
 				ResetObjectToPlace();
@@ -449,12 +449,11 @@ static void BuildRailToolbWndProc(Window *w, WindowEvent *e)
 				_remove_button_clicked = old;
 			} else if (e->place.userdata == VPM_SIGNALDIRS) {
 				HandleAutoSignalPlacement();
-			} else if (e->place.userdata == VPM_X_AND_Y) {
-				DoCommandP(end_tile, start_tile, 0, CcPlaySound10, CMD_CLEAR_AREA | CMD_MSG(STR_00B5_CAN_T_CLEAR_THIS_AREA));
-			} else if (e->place.userdata == (VPM_X_AND_Y | (1<<4))) {
-				DoCommandP(end_tile, start_tile, _cur_railtype, CcPlaySound10, CMD_CONVERT_RAIL | CMD_MSG(STR_CANT_CONVERT_RAIL));
-			} else if (e->place.userdata == (VPM_X_AND_Y | (2<<4))) {
-				DoCommandP(end_tile, start_tile, _cur_railtype, CcPlaySound10, CMD_LEVEL_LAND | CMD_AUTO);
+			} else if ((e->place.userdata & 0xF) == VPM_X_AND_Y) {
+				if (GUIPlaceProcDragXY(e)) break;
+
+				if ((e->place.userdata >> 0xF) == GUI_PlaceProc_ConvertRailArea)
+					DoCommandP(end_tile, start_tile, _cur_railtype, CcPlaySound10, CMD_CONVERT_RAIL | CMD_MSG(STR_CANT_CONVERT_RAIL));
 			} else if (e->place.userdata == VPM_X_AND_Y_LIMITED) {
 				HandleStationPlacement(start_tile, end_tile);
 			} else
diff --git a/table/sprites.h b/table/sprites.h
index 482d9ffed..13f02dcb6 100644
--- a/table/sprites.h
+++ b/table/sprites.h
@@ -677,9 +677,12 @@ enum Sprites {
 	SPR_IMG_TERRAFORM_DOWN  = 695,
 	SPR_IMG_DYNAMITE        = 703,
 	SPR_IMG_ROCKS           = 4084,
-	SPR_IMG_LIGHTHOUSE      = 4085,
+	SPR_IMG_LIGHTHOUSE_DESERT = 4085, // XXX - is Desert image on the desert-climate
 	SPR_IMG_TRANSMITTER     = 4086,
 	SPR_IMG_LEVEL_LAND      = SPR_OPENTTD_BASE + 68,
+	SPR_IMG_BUILD_CANAL     = SPR_OPENTTD_BASE + 65,
+	SPR_IMG_BUILD_LOCK      = SPR_CANALS_BASE + 69,
+	SPR_IMG_PLACE_SIGN      = SPR_OPENTTD_BASE + 70,
 	SPR_IMG_PAUSE           = 726,
 	SPR_IMG_FASTFORWARD     = SPR_OPENTTD_BASE + 57,
 	SPR_IMG_SETTINGS        = 751,
@@ -709,6 +712,7 @@ enum Sprites {
 	SPR_IMG_QUERY           = 723,
 	SPR_IMG_PLANTTREES      = 742,
 	SPR_IMG_SIGN            = 4082,
+	SPR_IMG_BUY_LAND        = 4791,
 
 	/* OPEN TRANSPORT TYCOON in gamescreen */
 	SPR_OTTD_O                = 4842,
diff --git a/terraform_gui.c b/terraform_gui.c
index 0221786e8..03572a82d 100644
--- a/terraform_gui.c
+++ b/terraform_gui.c
@@ -2,6 +2,7 @@
 #include "ttd.h"
 #include "table/sprites.h"
 #include "table/strings.h"
+#include "tile.h"
 #include "window.h"
 #include "gui.h"
 #include "viewport.h"
@@ -29,6 +30,59 @@ static void GenericRaiseLowerLand(uint tile, int mode)
 	}
 }
 
+/** 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;
+
+	BEGIN_TILE_LOOP(tile, size_x, size_y, TILE_XY(sx, sy)) {
+		if (GetTileType(tile) != MP_WATER)
+			SetMapExtraBits(tile, GetMapExtraBits(tile) == 1 ? 0 : 1);
+	} END_TILE_LOOP(tile, size_x, size_y, 0);
+}
+
+/**
+ * A central place to handle all X_AND_Y dragged GUI functions.
+ * @param we @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 *we)
+{
+	TileIndex start_tile = we->place.starttile;
+	TileIndex end_tile = we->place.tile;
+
+	switch (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_DesertArea >> 4:
+		GenerateDesertArea(end_tile, start_tile);
+		break;
+	case GUI_PlaceProc_WaterArea >> 4:
+		DoCommandP(end_tile, start_tile, 0, CcBuildCanal, CMD_BUILD_CANAL | CMD_AUTO | CMD_MSG(STR_CANT_BUILD_CANALS));
+		break;
+	default: return false;
+	}
+
+	return true;
+}
 
 typedef void OnButtonClick(Window *w);
 
@@ -44,7 +98,7 @@ static const uint16 _terraform_keycodes[] = {
 
 void PlaceProc_DemolishArea(uint tile)
 {
-	VpStartPlaceSizing(tile, VPM_X_AND_Y);
+	VpStartPlaceSizing(tile, VPM_X_AND_Y | GUI_PlaceProc_DemolishArea);
 }
 
 void PlaceProc_RaiseLand(uint tile)
@@ -59,12 +113,10 @@ void PlaceProc_LowerLand(uint tile)
 
 void PlaceProc_LevelLand(uint tile)
 {
-	VpStartPlaceSizing(tile, VPM_X_AND_Y | (2<<4));
+	VpStartPlaceSizing(tile, VPM_X_AND_Y | GUI_PlaceProc_LevelArea);
 }
 
-static void PlaceProc_PlantTree(uint tile)
-{
-}
+static void PlaceProc_PlantTree(uint tile) {}
 
 static void TerraformClick_Lower(Window *w)
 {
@@ -101,7 +153,6 @@ static void TerraformClick_PlaceSign(Window *w)
 	HandlePlacePushButton(w, 10, 722, 1, PlaceProc_Sign);
 }
 
-
 static OnButtonClick * const _terraform_button_proc[] = {
 	TerraformClick_Lower,
 	TerraformClick_Raise,
@@ -112,8 +163,6 @@ static OnButtonClick * const _terraform_button_proc[] = {
 	TerraformClick_PlaceSign,
 };
 
-
-
 static void TerraformToolbWndProc(Window *w, WindowEvent *e)
 {
 	switch(e->event) {
@@ -149,20 +198,8 @@ static void TerraformToolbWndProc(Window *w, WindowEvent *e)
 
 	case WE_PLACE_MOUSEUP:
 		if (e->click.pt.x != -1) {
-			uint start_tile = e->place.starttile;
-			uint end_tile = e->place.tile;
-
-			if (e->place.userdata == VPM_X_AND_Y) {
-				DoCommandP(end_tile, start_tile, 0, CcPlaySound10, CMD_CLEAR_AREA | CMD_MSG(STR_00B5_CAN_T_CLEAR_THIS_AREA));
-			} else if (e->place.userdata == (VPM_X_AND_Y | (2<<4))) {
-				DoCommandP(end_tile, start_tile, 0, CcPlaySound10, CMD_LEVEL_LAND | CMD_AUTO);
-			} else if (e->place.userdata == VPM_X_AND_Y_LIMITED) {
-//				if (e->click.pt.x != -1) {
-//					DoCommandP(e->place.tile, _tree_to_plant, e->place.starttile, NULL,
-//						CMD_PLANT_TREE | CMD_AUTO | CMD_MSG(STR_2805_CAN_T_PLANT_TREE_HERE));
-			} else {
-				assert(true);
-			}
+			if ((e->place.userdata & 0xF) == VPM_X_AND_Y) // dragged actions
+				GUIPlaceProcDragXY(e);
 		}
 		break;
 
@@ -182,20 +219,18 @@ static void TerraformToolbWndProc(Window *w, WindowEvent *e)
 }
 
 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, 0x0,                     STR_STICKY_BUTTON},
-
-{    WWT_PANEL,   RESIZE_NONE,     7,  66,  69,  14,  35,  0x0,										STR_NULL},
-
-{    WWT_PANEL,   RESIZE_NONE,     7,   0,  21,  14,  35,  695,										STR_018E_LOWER_A_CORNER_OF_LAND},
-{    WWT_PANEL,   RESIZE_NONE,     7,  22,  43,  14,  35,  694,										STR_018F_RAISE_A_CORNER_OF_LAND},
-{    WWT_PANEL,   RESIZE_NONE,     7,  44,  65,  14,  35,  SPR_OPENTTD_BASE+68,		STR_LEVEL_LAND_TOOLTIP},
-{    WWT_PANEL,   RESIZE_NONE,     7,  70,  91,  14,  35,  SPR_IMG_DYNAMITE,			STR_018D_DEMOLISH_BUILDINGS_ETC},
-{    WWT_PANEL,   RESIZE_NONE,     7,  92, 113,  14,  35,  4791,									STR_0329_PURCHASE_LAND_FOR_FUTURE},
-{    WWT_PANEL,   RESIZE_NONE,     7, 114, 135,  14,  35,  742,										STR_0185_PLANT_TREES_PLACE_SIGNS},
-{    WWT_PANEL,   RESIZE_NONE,     7, 136, 157,  14,  35,  SPR_OPENTTD_BASE+70,		STR_0289_PLACE_SIGN},
-
+{ 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, STR_NULL,                STR_NULL},
+{    WWT_PANEL,   RESIZE_NONE,     7,   0,  21,  14,  35, SPR_IMG_TERRAFORM_DOWN,  STR_018E_LOWER_A_CORNER_OF_LAND},
+{    WWT_PANEL,   RESIZE_NONE,     7,  22,  43,  14,  35, SPR_IMG_TERRAFORM_UP,    STR_018F_RAISE_A_CORNER_OF_LAND},
+{    WWT_PANEL,   RESIZE_NONE,     7,  44,  65,  14,  35, SPR_IMG_LEVEL_LAND,      STR_LEVEL_LAND_TOOLTIP},
+{    WWT_PANEL,   RESIZE_NONE,     7,  70,  91,  14,  35, SPR_IMG_DYNAMITE,        STR_018D_DEMOLISH_BUILDINGS_ETC},
+{    WWT_PANEL,   RESIZE_NONE,     7,  92, 113,  14,  35, SPR_IMG_BUY_LAND,        STR_0329_PURCHASE_LAND_FOR_FUTURE},
+{    WWT_PANEL,   RESIZE_NONE,     7, 114, 135,  14,  35, SPR_IMG_PLANTTREES,      STR_0185_PLANT_TREES_PLACE_SIGNS},
+{    WWT_PANEL,   RESIZE_NONE,     7, 136, 157,  14,  35, SPR_IMG_PLACE_SIGN,      STR_0289_PLACE_SIGN},
 
 {   WIDGETS_END},
 };
@@ -208,8 +243,6 @@ static const WindowDesc _terraform_desc = {
 	TerraformToolbWndProc
 };
 
-
-
 void ShowTerraformToolbar(void)
 {
 	if (_current_player == OWNER_SPECTATOR) return;
diff --git a/water_cmd.c b/water_cmd.c
index 64278cc0e..6a55e131e 100644
--- a/water_cmd.c
+++ b/water_cmd.c
@@ -179,33 +179,32 @@ int32 CmdBuildLock(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 
 int32 CmdBuildCanal(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 {
-	uint tile = TILE_FROM_XY(x,y);
-	int32 ret;
-	uint th;
-	uint endtile = (uint)p1;
-	int delta;
-	int32 cost;
+	int32 ret, cost;
+	int size_x, size_y;
+	int sx = TileX((TileIndex)p1);
+	int sy = TileY((TileIndex)p1);
+	x >>= 4; y >>= 4;
+
 	SET_EXPENSES_TYPE(EXPENSES_CONSTRUCTION);
 
-	// move in which direction?
-	delta = (TileX(tile) == TileX(endtile)) ? TILE_XY(0,1) : TILE_XY(1,0);
-	if (endtile < tile) delta = -delta;
+	if (x < sx) intswap(x, sx);
+	if (y < sy) intswap(y, sy);
+	size_x = (x - sx) + 1;
+	size_y = (y - sy) + 1;
 
 	cost = 0;
-	for(;;) {
+	BEGIN_TILE_LOOP(tile, size_x, size_y, TILE_XY(sx, sy)) {
 		ret = 0;
-		th = GetTileSlope(tile, NULL);
-		if(th!=0)
+		if (GetTileSlope(tile, NULL) != 0)
 			return_cmd_error(STR_0007_FLAT_LAND_REQUIRED);
 
 			// can't make water of water!
 			if (IsTileType(tile, MP_WATER)) {
 				_error_message = STR_1007_ALREADY_BUILT;
 			} else {
-
 				/* is middle piece of a bridge? */
 				if (IsTileType(tile, MP_TUNNELBRIDGE) && _map5[tile] & 0x40) { /* build under bridge */
-					if(_map5[tile] & 0x20) { // transport route under bridge
+					if (_map5[tile] & 0x20) { // transport route under bridge
 						_error_message = STR_5800_OBJECT_IN_THE_WAY;
 						ret = CMD_ERROR;
 					}
@@ -213,11 +212,10 @@ int32 CmdBuildCanal(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 						_error_message = STR_1007_ALREADY_BUILT;
 						ret = CMD_ERROR;
 					}
-
 				/* no bridge? then try to clear it. */
-				} else  {
+				} else
 					ret = DoCommandByTile(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
-				}
+
 				if (ret == CMD_ERROR) return ret;
 				cost += ret;
 
@@ -235,13 +233,9 @@ int32 CmdBuildCanal(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 
 				cost += _price.clear_water;
 			}
-		if (tile == endtile)
-			break;
-		tile += delta;
-	}
-	if (cost == 0) return CMD_ERROR;
+	} END_TILE_LOOP(tile, size_x, size_y, 0);
 
-	return cost;
+	return (cost == 0) ? CMD_ERROR : cost;
 }
 
 static int32 ClearTile_Water(uint tile, byte flags) {