Merge branch 'save_ext' into jgrpp

Conflicts:
	src/pathfinder/follow_track.hpp

src/aircraft_cmd.cpp

@@ -820,7 +820,7 @@ static byte AircraftGetEntryPoint(const Aircraft *v, const AirportFTAClass *apc,
 		/* We are northwest or southeast of the airport */
 		dir = delta_y < 0 ? DIAGDIR_NW : DIAGDIR_SE;
 	}
-	dir = ChangeDiagDir(dir, (DiagDirDiff)ReverseDiagDir(DirToDiagDir(rotation)));
+	dir = ChangeDiagDir(dir, DiagDirDifference(DIAGDIR_NE, DirToDiagDir(rotation)));
 	return apc->entry_points[dir];
 }
 

src/company_gui.cpp

@@ -1768,7 +1768,8 @@ struct CompanyInfrastructureWindow : Window
 
 				if (this->railtypes != RAILTYPES_NONE) {
 					/* Draw name of each valid railtype. */
-					for (RailType rt = RAILTYPE_BEGIN; rt != RAILTYPE_END; rt++) {
+					RailType rt;
+					FOR_ALL_SORTED_RAILTYPES(rt) {
 						if (HasBit(this->railtypes, rt)) {
 							SetDParam(0, GetRailTypeInfo(rt)->strings.name);
 							DrawString(r.left + offs_left, r.right - offs_right, y += FONT_HEIGHT_NORMAL, STR_WHITE_STRING);
@@ -1785,7 +1786,8 @@ struct CompanyInfrastructureWindow : Window
 			case WID_CI_RAIL_COUNT: {
 				/* Draw infrastructure count for each valid railtype. */
 				uint32 rail_total = c->infrastructure.GetRailTotal();
-				for (RailType rt = RAILTYPE_BEGIN; rt != RAILTYPE_END; rt++) {
+				RailType rt;
+				FOR_ALL_SORTED_RAILTYPES(rt) {
 					if (HasBit(this->railtypes, rt)) {
 						this->DrawCountLine(r, y, c->infrastructure.rail[rt], RailMaintenanceCost(rt, c->infrastructure.rail[rt], rail_total));
 					}

src/direction_func.h

@@ -61,11 +61,11 @@ static inline Direction ReverseDir(Direction d)
 
 
 /**
- * Calculate the difference between to directions
+ * Calculate the difference between two directions
  *
  * @param d0 The first direction as the base
  * @param d1 The second direction as the offset from the base
- * @return The difference how the second directions drifts of the first one.
+ * @return The difference how the second direction drifts of the first one.
  */
 static inline DirDiff DirDifference(Direction d0, Direction d1)
 {
@@ -79,7 +79,7 @@ static inline DirDiff DirDifference(Direction d0, Direction d1)
 /**
  * Applies two differences together
  *
- * This function adds two differences together and return the resulting
+ * This function adds two differences together and returns the resulting
  * difference. So adding two DIRDIFF_REVERSE together results in the
  * DIRDIFF_SAME difference.
  *
@@ -123,6 +123,20 @@ static inline DiagDirection ReverseDiagDir(DiagDirection d)
 	return (DiagDirection)(2 ^ d);
 }
 
+/**
+ * Calculate the difference between two DiagDirection values
+ *
+ * @param d0 The first direction as the base
+ * @param d1 The second direction as the offset from the base
+ * @return The difference how the second direction drifts of the first one.
+ */
+static inline DiagDirDiff DiagDirDifference(DiagDirection d0, DiagDirection d1)
+{
+	assert(IsValidDiagDirection(d0));
+	assert(IsValidDiagDirection(d1));
+	/* Cast to uint so compiler can use bitmask. Result can never be negative. */
+	return (DiagDirDiff)((uint)(d0 - d1) % 4);
+}
 
 /**
  * Applies a difference on a DiagDirection

src/lang/welsh.txt

@@ -284,8 +284,8 @@ STR_SORT_BY_PRODUCTION                                          :Cynyrch
 STR_SORT_BY_TYPE                                                :Math
 STR_SORT_BY_TRANSPORTED                                         :Wedi'i gludo
 STR_SORT_BY_NUMBER                                              :Rhif
-STR_SORT_BY_PROFIT_LAST_YEAR                                    :Elw eleni
-STR_SORT_BY_PROFIT_THIS_YEAR                                    :Elw llynedd
+STR_SORT_BY_PROFIT_LAST_YEAR                                    :Elw llynedd
+STR_SORT_BY_PROFIT_THIS_YEAR                                    :Elw eleni
 STR_SORT_BY_AGE                                                 :Oed
 STR_SORT_BY_RELIABILITY                                         :Dibynadwyedd
 STR_SORT_BY_TOTAL_CAPACITY_PER_CARGOTYPE                        :Cyfanswm Gallu Cludo fesul y math o lwyth

src/network/network_gui.cpp

@@ -1869,7 +1869,9 @@ struct NetworkClientListWindow : Window {
 	int selected_item;
 
 	uint server_client_width;
-	uint company_icon_width;
+	uint line_height;
+
+	Dimension icon_size;
 
 	NetworkClientListWindow(WindowDesc *desc, WindowNumber window_number) :
 			Window(desc),
@@ -1891,7 +1893,7 @@ struct NetworkClientListWindow : Window {
 			if (ci->client_playas != COMPANY_INACTIVE_CLIENT) num++;
 		}
 
-		num *= FONT_HEIGHT_NORMAL;
+		num *= this->line_height;
 
 		int diff = (num + WD_FRAMERECT_TOP + WD_FRAMERECT_BOTTOM) - (this->GetWidget<NWidgetBase>(WID_CL_PANEL)->current_y);
 		/* If height is changed */
@@ -1907,7 +1909,8 @@ struct NetworkClientListWindow : Window {
 		if (widget != WID_CL_PANEL) return;
 
 		this->server_client_width = max(GetStringBoundingBox(STR_NETWORK_SERVER).width, GetStringBoundingBox(STR_NETWORK_CLIENT).width) + WD_FRAMERECT_RIGHT;
-		this->company_icon_width = GetSpriteSize(SPR_COMPANY_ICON).width + WD_FRAMERECT_LEFT;
+		this->icon_size = GetSpriteSize(SPR_COMPANY_ICON);
+		this->line_height = max(this->icon_size.height + 2U, (uint)FONT_HEIGHT_NORMAL);
 
 		uint width = 100; // Default width
 		const NetworkClientInfo *ci;
@@ -1915,7 +1918,7 @@ struct NetworkClientListWindow : Window {
 			width = max(width, GetStringBoundingBox(ci->client_name).width);
 		}
 
-		size->width = WD_FRAMERECT_LEFT + this->server_client_width + this->company_icon_width + width + WD_FRAMERECT_RIGHT;
+		size->width = WD_FRAMERECT_LEFT + this->server_client_width + this->icon_size.width + WD_FRAMERECT_LEFT + width + WD_FRAMERECT_RIGHT;
 	}
 
 	virtual void OnPaint()
@@ -1931,11 +1934,13 @@ struct NetworkClientListWindow : Window {
 		if (widget != WID_CL_PANEL) return;
 
 		bool rtl = _current_text_dir == TD_RTL;
-		int icon_y_offset = 1 + (FONT_HEIGHT_NORMAL - 10) / 2;
+		int icon_offset = (this->line_height - icon_size.height) / 2;
+		int text_offset = (this->line_height - FONT_HEIGHT_NORMAL) / 2;
+
 		uint y = r.top + WD_FRAMERECT_TOP;
 		uint left = r.left + WD_FRAMERECT_LEFT;
 		uint right = r.right - WD_FRAMERECT_RIGHT;
-		uint type_icon_width = this->server_client_width + this->company_icon_width;
+		uint type_icon_width = this->server_client_width + this->icon_size.width + WD_FRAMERECT_LEFT;
 
 
 		uint type_left  = rtl ? right - this->server_client_width : left;
@@ -1949,24 +1954,24 @@ struct NetworkClientListWindow : Window {
 		FOR_ALL_CLIENT_INFOS(ci) {
 			TextColour colour;
 			if (this->selected_item == i++) { // Selected item, highlight it
-				GfxFillRect(r.left + 1, y, r.right - 1, y + FONT_HEIGHT_NORMAL - 1, PC_BLACK);
+				GfxFillRect(r.left + 1, y, r.right - 1, y + this->line_height - 1, PC_BLACK);
 				colour = TC_WHITE;
 			} else {
 				colour = TC_BLACK;
 			}
 
 			if (ci->client_id == CLIENT_ID_SERVER) {
-				DrawString(type_left, type_right, y, STR_NETWORK_SERVER, colour);
+				DrawString(type_left, type_right, y + text_offset, STR_NETWORK_SERVER, colour);
 			} else {
-				DrawString(type_left, type_right, y, STR_NETWORK_CLIENT, colour);
+				DrawString(type_left, type_right, y + text_offset, STR_NETWORK_CLIENT, colour);
 			}
 
 			/* Filter out spectators */
-			if (Company::IsValidID(ci->client_playas)) DrawCompanyIcon(ci->client_playas, icon_left, y + icon_y_offset);
+			if (Company::IsValidID(ci->client_playas)) DrawCompanyIcon(ci->client_playas, icon_left, y + icon_offset);
 
-			DrawString(name_left, name_right, y, ci->client_name, colour);
+			DrawString(name_left, name_right, y + text_offset, ci->client_name, colour);
 
-			y += FONT_HEIGHT_NORMAL;
+			y += line_height;
 		}
 	}
 
@@ -1999,7 +2004,7 @@ struct NetworkClientListWindow : Window {
 		pt.y -= this->GetWidget<NWidgetBase>(WID_CL_PANEL)->pos_y;
 		int item = -1;
 		if (IsInsideMM(pt.y, WD_FRAMERECT_TOP, this->GetWidget<NWidgetBase>(WID_CL_PANEL)->current_y - WD_FRAMERECT_BOTTOM)) {
-			item = (pt.y - WD_FRAMERECT_TOP) / FONT_HEIGHT_NORMAL;
+			item = (pt.y - WD_FRAMERECT_TOP) / this->line_height;
 		}
 
 		/* It did not change.. no update! */

src/order_gui.cpp

@@ -1966,6 +1966,12 @@ void ShowOrdersWindow(const Vehicle *v)
 	DeleteWindowById(WC_VEHICLE_TIMETABLE, v->index, false);
 	if (BringWindowToFrontById(WC_VEHICLE_ORDERS, v->index) != NULL) return;
 
+	/* Using a different WindowDescs for _local_company causes problems.
+	 * Due to this we have to close order windows in ChangeWindowOwner/DeleteCompanyWindows,
+	 * because we cannot change switch the WindowDescs and keeping the old WindowDesc results
+	 * in crashed due to missing widges.
+	 * TODO Rewrite the order GUI to not use different WindowDescs.
+	 */
 	if (v->owner != _local_company) {
 		new OrdersWindow(&_other_orders_desc, v);
 	} else {

src/pathfinder/follow_track.hpp

@@ -145,7 +145,12 @@ struct CFollowTrackT
 			 * missing road bit, or inability to connect the
 			 * different bits due to slopes. */
 			if (IsRoadTT() && !IsTram() && TryReverse()) return true;
+
+			/* CanEnterNewTile already set a reason.
+			 * Do NOT overwrite it (important for example for EC_RAIL_TYPE).
+			 * Only set a reason if CanEnterNewTile was not called */
 			if (m_new_td_bits == TRACKDIR_BIT_NONE) m_err = EC_NO_WAY;
+
 			return false;
 		}
 		if (!Allow90degTurns()) {

src/rail.h

@@ -431,4 +431,13 @@ void ResetRailTypes();
 void InitRailTypes();
 RailType AllocateRailType(RailTypeLabel label);
 
+extern RailType _sorted_railtypes[RAILTYPE_END];
+extern uint8 _sorted_railtypes_size;
+
+/**
+ * Loop header for iterating over railtypes, sorted by sortorder.
+ * @param var Railtype.
+ */
+#define FOR_ALL_SORTED_RAILTYPES(var) for (uint8 index = 0; index < _sorted_railtypes_size && (var = _sorted_railtypes[index], true) ; index++)
+
 #endif /* RAIL_H */

src/rail_cmd.cpp

@@ -46,6 +46,8 @@
 typedef SmallVector<Train *, 16> TrainList;
 
 RailtypeInfo _railtypes[RAILTYPE_END];
+RailType _sorted_railtypes[RAILTYPE_END];
+uint8 _sorted_railtypes_size;
 
 assert_compile(sizeof(_original_railtypes) <= sizeof(_railtypes));
 
@@ -113,6 +115,17 @@ void ResolveRailTypeGUISprites(RailtypeInfo *rti)
 	}
 }
 
+/**
+ * Compare railtypes based on their sorting order.
+ * @param first  The railtype to compare to.
+ * @param second The railtype to compare.
+ * @return True iff the first should be sorted before the second.
+ */
+static int CDECL CompareRailTypes(const RailType *first, const RailType *second)
+{
+	return GetRailTypeInfo(*first)->sorting_order - GetRailTypeInfo(*second)->sorting_order;
+}
+
 /**
  * Resolve sprites of custom rail types
  */
@@ -122,6 +135,14 @@ void InitRailTypes()
 		RailtypeInfo *rti = &_railtypes[rt];
 		ResolveRailTypeGUISprites(rti);
 	}
+
+	_sorted_railtypes_size = 0;
+	for (RailType rt = RAILTYPE_BEGIN; rt != RAILTYPE_END; rt++) {
+		if (_railtypes[rt].label != 0) {
+			_sorted_railtypes[_sorted_railtypes_size++] = rt;
+		}
+	}
+	QSortT(_sorted_railtypes, _sorted_railtypes_size, CompareRailTypes);
 }
 
 /**

src/rail_gui.cpp

@@ -2052,17 +2052,6 @@ void InitializeRailGUI()
 	ResetSignalVariant();
 }
 
-/**
- * Compare railtypes based on their sorting order.
- * @param first  The railtype to compare to.
- * @param second The railtype to compare.
- * @return True iff the first should be sorted before the second.
- */
-static int CDECL CompareRailTypes(const DropDownListItem * const *first, const DropDownListItem * const *second)
-{
-	return GetRailTypeInfo((RailType)(*first)->result)->sorting_order - GetRailTypeInfo((RailType)(*second)->result)->sorting_order;
-}
-
 /**
  * Create a drop down list for all the rail types of the local company.
  * @param for_replacement Whether this list is for the replacement window.
@@ -2085,13 +2074,12 @@ DropDownList *GetRailTypeDropDownList(bool for_replacement)
 
 	const Company *c = Company::Get(_local_company);
 	DropDownList *list = new DropDownList();
-	for (RailType rt = RAILTYPE_BEGIN; rt != RAILTYPE_END; rt++) {
+	RailType rt;
+	FOR_ALL_SORTED_RAILTYPES(rt) {
 		/* If it's not used ever, don't show it to the user. */
 		if (!HasBit(used_railtypes, rt)) continue;
 
 		const RailtypeInfo *rti = GetRailTypeInfo(rt);
-		/* Skip rail type if it has no label */
-		if (rti->label == 0) continue;
 
 		StringID str = for_replacement ? rti->strings.replace_text : (rti->max_speed > 0 ? STR_TOOLBAR_RAILTYPE_VELOCITY : STR_JUST_STRING);
 		DropDownListParamStringItem *item = new DropDownListParamStringItem(str, rt, !HasBit(c->avail_railtypes, rt));
@@ -2099,6 +2087,5 @@ DropDownList *GetRailTypeDropDownList(bool for_replacement)
 		item->SetParam(1, rti->max_speed);
 		*list->Append() = item;
 	}
-	QSortT(list->Begin(), list->Length(), CompareRailTypes);
 	return list;
 }

src/road.cpp

@@ -57,41 +57,44 @@ RoadBits CleanUpRoadBits(const TileIndex tile, RoadBits org_rb)
 			bool connective = false;
 			const RoadBits mirrored_rb = MirrorRoadBits(target_rb);
 
-			switch (GetTileType(neighbor_tile)) {
-				/* Always connective ones */
-				case MP_CLEAR: case MP_TREES:
-					connective = true;
-					break;
-
-				/* The conditionally connective ones */
-				case MP_TUNNELBRIDGE:
-				case MP_STATION:
-				case MP_ROAD: {
-					const RoadBits neighbor_rb = GetAnyRoadBits(neighbor_tile, ROADTYPE_ROAD) | GetAnyRoadBits(neighbor_tile, ROADTYPE_TRAM);
-
-					/* Accept only connective tiles */
-					connective = (neighbor_rb & mirrored_rb) || // Neighbor has got the fitting RoadBit
-							HasExactlyOneBit(neighbor_rb); // Neighbor has got only one Roadbit
-
-					break;
+			if (IsValidTile(neighbor_tile)) {
+				switch (GetTileType(neighbor_tile)) {
+					/* Always connective ones */
+					case MP_CLEAR: case MP_TREES:
+						connective = true;
+						break;
+
+					/* The conditionally connective ones */
+					case MP_TUNNELBRIDGE:
+					case MP_STATION:
+					case MP_ROAD:
+						if (IsNormalRoadTile(neighbor_tile)) {
+							/* Always connective */
+							connective = true;
+						} else {
+							const RoadBits neighbor_rb = GetAnyRoadBits(neighbor_tile, ROADTYPE_ROAD) | GetAnyRoadBits(neighbor_tile, ROADTYPE_TRAM);
+
+							/* Accept only connective tiles */
+							connective = (neighbor_rb & mirrored_rb) != ROAD_NONE;
+						}
+						break;
+
+					case MP_RAILWAY:
+						connective = IsPossibleCrossing(neighbor_tile, DiagDirToAxis(dir));
+						break;
+
+					case MP_WATER:
+						/* Check for real water tile */
+						connective = !IsWater(neighbor_tile);
+						break;
+
+					/* The definitely not connective ones */
+					default: break;
 				}
-
-				case MP_RAILWAY:
-					connective = IsPossibleCrossing(neighbor_tile, DiagDirToAxis(dir));
-					break;
-
-				case MP_WATER:
-					/* Check for real water tile */
-					connective = !IsWater(neighbor_tile);
-					break;
-
-				/* The definitely not connective ones */
-				default: break;
 			}
 
 			/* If the neighbor tile is inconnective, remove the planed road connection to it */
 			if (!connective) org_rb ^= target_rb;
-
 		}
 	}
 

src/saveload/saveload.cpp

@@ -570,7 +570,7 @@ void NORETURN SlError(StringID string, const char *extra_msg, bool already_mallo
 /**
  * As SlError, except that it takes a format string and additional parameters
  */
-void CDECL NORETURN SlErrorFmt(StringID string, const char *msg, ...)
+void NORETURN CDECL SlErrorFmt(StringID string, const char *msg, ...)
 {
 	va_list va;
 	va_start(va, msg);
@@ -594,7 +594,7 @@ void NORETURN SlErrorCorrupt(const char *msg, bool already_malloced)
 /**
  * As SlErrorCorruptFmt, except that it takes a format string and additional parameters
  */
-void CDECL NORETURN SlErrorCorruptFmt(const char *msg, ...)
+void NORETURN CDECL SlErrorCorruptFmt(const char *msg, ...)
 {
 	va_list va;
 	va_start(va, msg);

src/saveload/saveload.h

@@ -631,8 +631,8 @@ void SlObject(void *object, const SaveLoad *sld);
 bool SlObjectMember(void *object, const SaveLoad *sld);
 void NORETURN SlError(StringID string, const char *extra_msg = NULL, bool already_malloced = false);
 void NORETURN SlErrorCorrupt(const char *msg, bool already_malloced = false);
-void CDECL NORETURN SlErrorFmt(StringID string, const char *msg, ...) WARN_FORMAT(2, 3);
-void CDECL NORETURN SlErrorCorruptFmt(const char *msg, ...) WARN_FORMAT(1, 2);
+void NORETURN CDECL SlErrorFmt(StringID string, const char *msg, ...) WARN_FORMAT(2, 3);
+void NORETURN CDECL SlErrorCorruptFmt(const char *msg, ...) WARN_FORMAT(1, 2);
 
 bool SaveloadCrashWithMissingNewGRFs();
 

src/town_cmd.cpp

@@ -1395,8 +1395,8 @@ static void GrowTownInTile(TileIndex *tile_ptr, RoadBits cur_rb, DiagDirection t
 					/* FALL THROUGH */
 
 				case TL_2X2_GRID:
-					rcmd = GetTownRoadGridElement(t1, house_tile, target_dir);
-					allow_house = (rcmd == ROAD_NONE);
+					rcmd = GetTownRoadGridElement(t1, tile, target_dir);
+					allow_house = (rcmd & DiagDirToRoadBits(target_dir)) == ROAD_NONE;
 					break;
 
 				case TL_BETTER_ROADS: // Use original afterwards!
@@ -1526,13 +1526,12 @@ static bool GrowTownAtRoad(Town *t, TileIndex tile)
 
 		/* Try to grow the town from this point */
 		GrowTownInTile(&tile, cur_rb, target_dir, t);
+		if (_grow_town_result == GROWTH_SUCCEED) return true;
 
 		/* Exclude the source position from the bitmask
 		 * and return if no more road blocks available */
 		if (IsValidDiagDirection(target_dir)) cur_rb &= ~DiagDirToRoadBits(ReverseDiagDir(target_dir));
-		if (cur_rb == ROAD_NONE) {
-			return _grow_town_result == GROWTH_SUCCEED;
-		}
+		if (cur_rb == ROAD_NONE) return false;
 
 		if (IsTileType(tile, MP_TUNNELBRIDGE)) {
 			/* Only build in the direction away from the tunnel or bridge. */
@@ -1567,7 +1566,7 @@ static bool GrowTownAtRoad(Town *t, TileIndex tile)
 		/* Max number of times is checked. */
 	} while (--_grow_town_result >= 0);
 
-	return _grow_town_result == GROWTH_SUCCEED - 1;
+	return false;
 }
 
 /**

src/train_cmd.cpp

@@ -1439,13 +1439,15 @@ CommandCost CmdSellRailWagon(DoCommandFlag flags, Vehicle *t, uint16 data, uint3
 		return ret;
 	}
 
-	CommandCost cost(EXPENSES_NEW_VEHICLES);
-	for (Train *t = sell_head; t != NULL; t = t->Next()) cost.AddCost(-t->value);
-
 	if (first->orders.list == NULL && !OrderList::CanAllocateItem()) {
+		/* Restore the train we had. */
+		RestoreTrainBackup(original);
 		return_cmd_error(STR_ERROR_NO_MORE_SPACE_FOR_ORDERS);
 	}
 
+	CommandCost cost(EXPENSES_NEW_VEHICLES);
+	for (Train *t = sell_head; t != NULL; t = t->Next()) cost.AddCost(-t->value);
+
 	/* do it? */
 	if (flags & DC_EXEC) {
 		/* First normalise the sub types of the chain. */

src/vehicle.cpp

@@ -1611,6 +1611,9 @@ void AgeVehicle(Vehicle *v)
  * @param front The front vehicle of the consist to check.
  * @param colour The string to show depending on if we are unloading or loading
  * @return A percentage of how full the Vehicle is.
+ *         Percentages are rounded towards 50%, so that 0% and 100% are only returned
+ *         if the vehicle is completely empty or full.
+ *         This is useful for both display and conditional orders.
  */
 uint8 CalcPercentVehicleFilled(const Vehicle *front, StringID *colour)
 {
@@ -1658,7 +1661,13 @@ uint8 CalcPercentVehicleFilled(const Vehicle *front, StringID *colour)
 	if (max == 0) return 100;
 
 	/* Return the percentage */
-	return (count * 100) / max;
+	if (count * 2 < max) {
+		/* Less than 50%; round up, so that 0% means really empty. */
+		return CeilDiv(count * 100, max);
+	} else {
+		/* More than 50%; round down, so that 100% means really full. */
+		return (count * 100) / max;
+	}
 }
 
 /**

src/vehicle_cmd.cpp

@@ -386,8 +386,10 @@ static CommandCost RefitVehicle(Vehicle *v, bool only_this, uint8 num_vehicles,
 
 		bool auto_refit_allowed;
 		CommandCost refit_cost = GetRefitCost(v, v->engine_type, new_cid, actual_subtype, &auto_refit_allowed);
-		if (auto_refit && !auto_refit_allowed) {
-			/* Sorry, auto-refitting not allowed, subtract the cargo amount again from the total. */
+		if (auto_refit && (flags & DC_QUERY_COST) == 0 && !auto_refit_allowed) {
+			/* Sorry, auto-refitting not allowed, subtract the cargo amount again from the total.
+			 * When querrying cost/capacity (for example in order refit GUI), we always assume 'allowed'.
+			 * It is not predictable. */
 			total_capacity -= amount;
 			total_mail_capacity -= mail_capacity;
 
@@ -474,8 +476,15 @@ CommandCost CmdRefitVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint
 
 	/* Don't allow shadows and such to be refitted. */
 	if (v != front && (v->type == VEH_SHIP || v->type == VEH_AIRCRAFT)) return CMD_ERROR;
+
 	/* Allow auto-refitting only during loading and normal refitting only in a depot. */
-	if (!free_wagon && (!auto_refit || !front->current_order.IsType(OT_LOADING)) && !front->IsStoppedInDepot()) return_cmd_error(STR_ERROR_TRAIN_MUST_BE_STOPPED_INSIDE_DEPOT + front->type);
+	if ((flags & DC_QUERY_COST) == 0 && // used by the refit GUI, including the order refit GUI.
+			!free_wagon && // used by autoreplace/renew
+			(!auto_refit || !front->current_order.IsType(OT_LOADING)) && // refit inside stations
+			!front->IsStoppedInDepot()) { // refit inside depots
+		return_cmd_error(STR_ERROR_TRAIN_MUST_BE_STOPPED_INSIDE_DEPOT + front->type);
+	}
+
 	if (front->vehstatus & VS_CRASHED) return_cmd_error(STR_ERROR_VEHICLE_IS_DESTROYED);
 
 	/* Check cargo */

src/vehicle_gui.cpp

@@ -754,7 +754,10 @@ struct RefitWindow : public Window {
 		if (_returned_mail_refit_capacity > 0) {
 			SetDParam(2, CT_MAIL);
 			SetDParam(3, _returned_mail_refit_capacity);
-			if (money <= 0) {
+			if (this->order != INVALID_VEH_ORDER_ID) {
+				/* No predictable cost */
+				return STR_PURCHASE_INFO_AIRCRAFT_CAPACITY;
+			} else if (money <= 0) {
 				SetDParam(4, -money);
 				return STR_REFIT_NEW_CAPACITY_INCOME_FROM_AIRCRAFT_REFIT;
 			} else {
@@ -762,7 +765,11 @@ struct RefitWindow : public Window {
 				return STR_REFIT_NEW_CAPACITY_COST_OF_AIRCRAFT_REFIT;
 			}
 		} else {
-			if (money <= 0) {
+			if (this->order != INVALID_VEH_ORDER_ID) {
+				/* No predictable cost */
+				SetDParam(2, STR_EMPTY);
+				return STR_PURCHASE_INFO_CAPACITY;
+			} else if (money <= 0) {
 				SetDParam(2, -money);
 				return STR_REFIT_NEW_CAPACITY_INCOME_FROM_REFIT;
 			} else {

src/window.cpp

@@ -1207,6 +1207,7 @@ void ChangeWindowOwner(Owner old_owner, Owner new_owner)
 			case WC_BUY_COMPANY:
 			case WC_COMPANY:
 			case WC_COMPANY_INFRASTRUCTURE:
+			case WC_VEHICLE_ORDERS: // Changing owner would also require changing WindowDesc, which is not possible; however keeping the old one crashes because of missing widgets etc.. See ShowOrdersWindow().
 				continue;
 
 			default:

src/zoom_func.h

@@ -67,7 +67,7 @@ static inline int UnScaleByZoomLower(int value, ZoomLevel zoom)
 /**
  * Short-hand to apply GUI zoom level.
  * @param value Pixel amount at #ZOOM_LVL_BEGIN (full zoom in).
- * @return value Pixel amount at #ZOOM_LVL_GUI.
+ * @return Pixel amount at #ZOOM_LVL_GUI (current interface size).
  */
 static inline int UnScaleGUI(int value)
 {
@@ -76,8 +76,8 @@ static inline int UnScaleGUI(int value)
 
 /**
  * Scale traditional pixel dimensions to GUI zoom level.
- * @param value Pixel amount at 1x zoom level.
- * @return value Pixel amount at #ZOOM_LVL_GUI.
+ * @param value Pixel amount at #ZOOM_LVL_BASE (traditional "normal" interface size).
+ * @return Pixel amount at #ZOOM_LVL_GUI (current interface size).
  */
 static inline int ScaleGUITrad(int value)
 {