(svn r18404) -Codechange: link drive through stops better together

-Feature: make penalty for road stop occupancy user configurable
-Fix [FS#1944]: road vehicles would not pick an empty drive through stop. Now they will *if* the penalty for driving around is less than the occupancy penalty
-Fix [FS#1495]: long (articulated) road vehicles could block loading of others when the following road vehicle already got 'permission' to go to the next bay even when it could not reach it
-Change: improve the throughput of the drive through road stops by letting them stop closer together

1 files changed, 65 insertions, 0 deletions

diff --git a/src/roadstop_base.h b/src/roadstop_base.h
index c3cd359bd..5c73d233f 100644
--- a/src/roadstop_base.h
+++ b/src/roadstop_base.h
@@ -25,9 +25,46 @@ struct RoadStop : RoadStopPool::PoolItem<&_roadstop_pool> {
 		RSSFB_BAY0_FREE  = 0, ///< Non-zero when bay 0 is free
 		RSSFB_BAY1_FREE  = 1, ///< Non-zero when bay 1 is free
 		RSSFB_BAY_COUNT  = 2, ///< Max. number of bays
+		RSSFB_BASE_ENTRY = 6, ///< Non-zero when the entries on this road stop are the primary, i.e. the ones to delete
 		RSSFB_ENTRY_BUSY = 7, ///< Non-zero when roadstop entry is busy
 	};
 
+	/** Container for each entry point of a drive through road stop */
+	struct Entry {
+	private:
+		int length;      ///< The length of the stop in tile 'units'
+		int occupied;    ///< The amount of occupied stop in tile 'units'
+
+	public:
+		friend class RoadStop; ///< Oh yeah, the road stop may play with me.
+
+		/** Create an entry */
+		Entry() : length(0), occupied(0) {}
+
+		/**
+		 * Get the length of this drive through stop.
+		 * @return the length in tile units.
+		 */
+		FORCEINLINE int GetLength() const
+		{
+			return this->length;
+		}
+
+		/**
+		 * Get the amount of occupied space in this drive through stop.
+		 * @return the occupied space in tile units.
+		 */
+		FORCEINLINE int GetOccupied() const
+		{
+			return this->occupied;
+		}
+
+		void Leave(const RoadVehicle *rv);
+		void Enter(const RoadVehicle *rv);
+		void CheckIntegrity(const RoadStop *rs) const;
+		void Rebuild(const RoadStop *rs, int side = -1);
+	};
+
 	static const uint LIMIT           = 16;  ///< The maximum amount of roadstops that are allowed at a single station
 
 	TileIndex        xy;                    ///< Position on the map
@@ -80,6 +117,29 @@ struct RoadStop : RoadStopPool::PoolItem<&_roadstop_pool> {
 		SB(this->status, RSSFB_ENTRY_BUSY, 1, busy);
 	}
 
+	/**
+	 * Get the drive through road stop entry struct for the given direction.
+	 * @param direction the direciton to get the entry for
+	 * @return the entry
+	 */
+	FORCEINLINE const Entry *GetEntry(DiagDirection dir) const
+	{
+		return HasBit((int)dir, 1) ? this->west : this->east;
+	}
+
+	/**
+	 * Get the drive through road stop entry struct for the given direction.
+	 * @param direction the direciton to get the entry for
+	 * @return the entry
+	 */
+	FORCEINLINE Entry *GetEntry(DiagDirection dir)
+	{
+		return HasBit((int)dir, 1) ? this->west : this->east;
+	}
+
+	void MakeDriveThrough();
+	void ClearDriveThrough();
+
 	void Leave(RoadVehicle *rv);
 	bool Enter(RoadVehicle *rv);
 
@@ -87,7 +147,12 @@ struct RoadStop : RoadStopPool::PoolItem<&_roadstop_pool> {
 
 	static RoadStop *GetByTile(TileIndex tile, RoadStopType type);
 
+	static bool IsDriveThroughRoadStopContinuation(TileIndex rs, TileIndex next);
+
 private:
+	Entry *east; ///< The vehicles that entered from the east
+	Entry *west; ///< The vehicles that entered from the west
+
 	/**
 	 * Allocates a bay
 	 * @return the allocated bay number