Fix: Some code and comment typos

Found with codespell

src/openttd.cpp

@@ -278,7 +278,7 @@ static void ParseResolution(Dimension *res, const char *s)
 
 
 /**
- * Unitializes drivers, frees allocated memory, cleans pools, ...
+ * Uninitializes drivers, frees allocated memory, cleans pools, ...
  * Generally, prepares the game for shutting down
  */
 static void ShutdownGame()

src/station_cmd.cpp

@@ -1767,16 +1767,16 @@ CommandCost CmdBuildRoadStop(TileIndex tile, DoCommandFlag flags, uint32 p1, uin
 	bool distant_join = (station_to_join != INVALID_STATION);
 
 	uint8 width = (uint8)GB(p1, 0, 8);
-	uint8 lenght = (uint8)GB(p1, 8, 8);
+	uint8 length = (uint8)GB(p1, 8, 8);
 
 	/* Check if the requested road stop is too big */
-	if (width > _settings_game.station.station_spread || lenght > _settings_game.station.station_spread) return_cmd_error(STR_ERROR_STATION_TOO_SPREAD_OUT);
+	if (width > _settings_game.station.station_spread || length > _settings_game.station.station_spread) return_cmd_error(STR_ERROR_STATION_TOO_SPREAD_OUT);
 	/* Check for incorrect width / length. */
-	if (width == 0 || lenght == 0) return CMD_ERROR;
+	if (width == 0 || length == 0) return CMD_ERROR;
 	/* Check if the first tile and the last tile are valid */
-	if (!IsValidTile(tile) || TileAddWrap(tile, width - 1, lenght - 1) == INVALID_TILE) return CMD_ERROR;
+	if (!IsValidTile(tile) || TileAddWrap(tile, width - 1, length - 1) == INVALID_TILE) return CMD_ERROR;
 
-	TileArea roadstop_area(tile, width, lenght);
+	TileArea roadstop_area(tile, width, length);
 
 	if (distant_join && (!_settings_game.station.distant_join_stations || !Station::IsValidID(station_to_join))) return CMD_ERROR;
 
@@ -3433,7 +3433,7 @@ void RerouteCargo(Station *st, CargoID c, StationID avoid, StationID avoid2)
 	/* Reroute cargo in station. */
 	ge.cargo.Reroute(UINT_MAX, &ge.cargo, avoid, avoid2, &ge);
 
-	/* Reroute cargo staged to be transfered. */
+	/* Reroute cargo staged to be transferred. */
 	for (std::list<Vehicle *>::iterator it(st->loading_vehicles.begin()); it != st->loading_vehicles.end(); ++it) {
 		for (Vehicle *v = *it; v != NULL; v = v->Next()) {
 			if (v->cargo_type != c) continue;
@@ -3443,7 +3443,7 @@ void RerouteCargo(Station *st, CargoID c, StationID avoid, StationID avoid2)
 }
 
 /**
- * Check all next hops of cargo packets in this station for existance of a
+ * Check all next hops of cargo packets in this station for existence of a
  * a valid link they may use to travel on. Reroute any cargo not having a valid
  * link and remove timed out links found like this from the linkgraph. We're
  * not all links here as that is expensive and useless. A link no one is using
@@ -4230,7 +4230,7 @@ void FlowStat::Invalidate()
 }
 
 /**
- * Change share for specified station. By specifing INT_MIN as parameter you
+ * Change share for specified station. By specifying INT_MIN as parameter you
  * can erase a share. Newly added flows will be unrestricted.
  * @param st Next Hop to be removed.
  * @param flow Share to be added or removed.

src/station_gui.cpp

@@ -657,7 +657,7 @@ const CargoTypes CompanyStationsWindow::cargo_filter_max = ALL_CARGOTYPES;
 CargoTypes CompanyStationsWindow::cargo_filter = ALL_CARGOTYPES;
 const Station *CompanyStationsWindow::last_station = NULL;
 
-/* Availible station sorting functions */
+/* Available station sorting functions */
 GUIStationList::SortFunction * const CompanyStationsWindow::sorter_funcs[] = {
 	&StationNameSorter,
 	&StationTypeSorter,

src/tgp.cpp

@@ -47,7 +47,7 @@
  * second sets the major variations to that, ... until finally the smallest
  * bumps are added.
  *
- * Usefully, this routine is totally scaleable; so when 32bpp comes along, the
+ * Usefully, this routine is totally scalable; so when 32bpp comes along, the
  * terrain can be as bumpy as you like! It is also infinitely expandable; a
  * single random seed terrain continues in X & Y as far as you care to
  * calculate. In theory, we could use just one seed value, but randomly select
@@ -262,7 +262,7 @@ static amplitude_t GetAmplitude(int frequency)
 	 * areas with a particular gradient so that we are able to create maps without too
 	 * many steep slopes up to the wanted height level. It's definitely not perfect since
 	 * it will bring larger rectangles with similar slopes which makes the rectangular
-	 * behaviour of TGP more noticable. However, these height differentiations cannot
+	 * behaviour of TGP more noticeable. However, these height differentiations cannot
 	 * happen over much smaller areas; we basically double the "range" to give a similar
 	 * slope for every doubling of map height.
 	 */
@@ -977,7 +977,7 @@ static void TgenSetTileHeight(TileIndex tile, int height)
  * The main new land generator using Perlin noise. Desert landscape is handled
  * different to all others to give a desert valley between two high mountains.
  * Clearly if a low height terrain (flat/very flat) is chosen, then the tropic
- * areas wont be high enough, and there will be very little tropic on the map.
+ * areas won't be high enough, and there will be very little tropic on the map.
  * Thus Tropic works best on Hilly or Mountainous.
  */
 void GenerateTerrainPerlin()

src/town_cmd.cpp

@@ -2945,7 +2945,7 @@ static CommandCost TownActionFundBuildings(Town *t, DoCommandFlag flags)
 		 * Also emulate original behaviour when town was only growing in
 		 * TOWN_GROWTH_TICKS intervals, to make sure that it's not too
 		 * tick-perfect and gives player some time window where he can
-		 * spam funding with the exact same effeciency.
+		 * spam funding with the exact same efficiency.
 		 */
 		t->grow_counter = min(t->grow_counter, 2 * TOWN_GROWTH_TICKS - (t->growth_rate - t->grow_counter) % TOWN_GROWTH_TICKS);
 

src/vehicle.cpp

@@ -723,7 +723,7 @@ bool Vehicle::IsEngineCountable() const
 
 /**
  * Check whether Vehicle::engine_type has any meaning.
- * @return true if the vehicle has a useable engine type.
+ * @return true if the vehicle has a usable engine type.
  */
 bool Vehicle::HasEngineType() const
 {

src/viewport.cpp

@@ -58,7 +58,7 @@
  *
  *
  * Rows are horizontal sections of the viewport, also half a tile wide.
- * This time the nothern most tile on the map defines 0 and
+ * This time the northern most tile on the map defines 0 and
  * everything south of that has a positive number.
  */
 

src/window.cpp

@@ -655,7 +655,7 @@ static void DispatchLeftClickEvent(Window *w, int x, int y, int click_count)
 
 	/* Clicked on a widget that is not disabled.
 	 * So unless the clicked widget is the caption bar, change focus to this widget.
-	 * Exception: In the OSK we always want the editbox to stay focussed. */
+	 * Exception: In the OSK we always want the editbox to stay focused. */
 	if (widget_type != WWT_CAPTION && w->window_class != WC_OSK) {
 		/* focused_widget_changed is 'now' only true if the window this widget
 		 * is in gained focus. In that case it must remain true, also if the