(svn r25097) -Feature[FS#5288]: Add sorting on rating for the town directory window (based on work by sbr).

src/lang/english.txt

@@ -289,6 +289,7 @@ STR_SORT_BY_POWER_VS_RUNNING_COST                               :Power/Running C
 STR_SORT_BY_CARGO_CAPACITY                                      :Cargo Capacity
 STR_SORT_BY_RANGE                                               :Range
 STR_SORT_BY_POPULATION                                          :Population
+STR_SORT_BY_RATING                                              :Rating
 
 # Tooltips for the main toolbar
 STR_TOOLBAR_TOOLTIP_PAUSE_GAME                                  :{BLACK}Pause game

src/town_gui.cpp

@@ -691,6 +691,25 @@ private:
 		return (a_population > b_population) ? -1 : 1;
 	}
 
+	/** Sort by town rating */
+	static int CDECL TownRatingSorter(const Town * const *a, const Town * const *b)
+	{
+		int before = TownDirectoryWindow::last_sorting.order ? 1 : -1; // Value to get 'a' before 'b'.
+
+		/* Towns without rating are always after towns with rating. */
+		if (HasBit((*a)->have_ratings, _local_company)) {
+			if (HasBit((*b)->have_ratings, _local_company)) {
+				int16 a_rating = (*a)->ratings[_local_company];
+				int16 b_rating = (*b)->ratings[_local_company];
+				if (a_rating == b_rating) return TownDirectoryWindow::TownNameSorter(a, b);
+				return (a_rating > b_rating) ? -1 : 1;
+			}
+			return before;
+		}
+		if (HasBit((*b)->have_ratings, _local_company)) return -before;
+		return -before * TownDirectoryWindow::TownNameSorter(a, b); // Sort unrated towns always on ascending town name.
+	}
+
 public:
 	TownDirectoryWindow(const WindowDesc *desc) : Window()
 	{
@@ -823,8 +842,16 @@ public:
 	{
 		switch (widget) {
 			case WID_TD_SORT_ORDER: // Click on sort order button
-				this->towns.ToggleSortOrder();
-				this->last_sorting = this->towns.GetListing(); // Store new sorting order.
+				if (this->towns.SortType() != 2) { // A different sort than by rating.
+					this->towns.ToggleSortOrder();
+					this->last_sorting = this->towns.GetListing(); // Store new sorting order.
+				} else {
+					/* Some parts are always sorted ascending on name. */
+					this->last_sorting.order = !this->last_sorting.order;
+					this->towns.SetListing(this->last_sorting);
+					this->towns.ForceResort();
+					this->towns.Sort();
+				}
 				this->SetDirty();
 				break;
 
@@ -899,6 +926,7 @@ const Town *TownDirectoryWindow::last_town = NULL;
 const StringID TownDirectoryWindow::sorter_names[] = {
 	STR_SORT_BY_NAME,
 	STR_SORT_BY_POPULATION,
+	STR_SORT_BY_RATING,
 	INVALID_STRING_ID
 };
 
@@ -906,6 +934,7 @@ const StringID TownDirectoryWindow::sorter_names[] = {
 GUITownList::SortFunction * const TownDirectoryWindow::sorter_funcs[] = {
 	&TownNameSorter,
 	&TownPopulationSorter,
+	&TownRatingSorter,
 };
 
 static const WindowDesc _town_directory_desc(