(svn r1963) - Add: [NPF] Penalty for a red signal that is the last signal on the path.

- Add: [NPF] NPFGetFlag() and NPFSetFlag() to wrap NPF node flag handling

8 files changed, 97 insertions, 29 deletions

diff --git a/ai_pathfinder.c b/ai_pathfinder.c
index 76471a123..fe8c4d5ca 100644
--- a/ai_pathfinder.c
+++ b/ai_pathfinder.c
@@ -50,14 +50,19 @@ static bool IsRoad(TileIndex tile)
 #define TILES_BETWEEN(a, b, c) (TileX(a) >= TileX(b) && TileX(a) <= TileX(c) && TileY(a) >= TileY(b) && TileY(a) <= TileY(c))
 
 // Check if the current tile is in our end-area
-static int32 AyStar_AiPathFinder_EndNodeCheck(AyStar *aystar, OpenListNode *current)
+static int32 AyStar_AiPathFinder_EndNodeCheck(AyStar *aystar, AyStarNode *node)
 {
 	Ai_PathFinderInfo *PathFinderInfo = (Ai_PathFinderInfo*)aystar->user_target;
 	// It is not allowed to have a station on the end of a bridge or tunnel ;)
-	if (current->path.node.user_data[0] != 0) return AYSTAR_DONE;
-	if (TILES_BETWEEN(current->path.node.tile, PathFinderInfo->end_tile_tl, PathFinderInfo->end_tile_br))
-		if (IsTileType(current->path.node.tile, MP_CLEAR) || IsTileType(current->path.node.tile, MP_TREES))
-			if (current->path.parent == NULL || TestCanBuildStationHere(current->path.node.tile,AiNew_GetDirection(current->path.parent->node.tile, current->path.node.tile)))
+	if (node->user_data[0] != 0) return AYSTAR_DONE;
+	if (TILES_BETWEEN(node->tile, PathFinderInfo->end_tile_tl, PathFinderInfo->end_tile_br))
+		if (IsTileType(node->tile, MP_CLEAR) || IsTileType(node->tile, MP_TREES))
+			/* XXX: The next line used to be here, but the argument to this function
+			 * changed to an AyStarNode* instead of an OpenListNode*, so we don't
+			 * have the parent available here anymore. Still, if we can build a
+			 * station in anyone direction, we can build it in any direction, right?*/
+			// if (current->path.parent == NULL || TestCanBuildStationHere(node->tile,AiNew_GetDirection(current->path.parent->node.tile, node->tile)))
+			if ( TestCanBuildStationHere(node->tile,0))
     			return AYSTAR_FOUND_END_NODE;
 
 	return AYSTAR_DONE;
diff --git a/aystar.c b/aystar.c
index 22d4ba813..4ed9058b8 100644
--- a/aystar.c
+++ b/aystar.c
@@ -146,7 +146,7 @@ int AyStarMain_Loop(AyStar *aystar) {
 	if (current == NULL) return AYSTAR_EMPTY_OPENLIST;
 
 	// Check for end node and if found, return that code
-	if (aystar->EndNodeCheck(aystar, current) == AYSTAR_FOUND_END_NODE) {
+	if (aystar->EndNodeCheck(aystar, &current->path.node) == AYSTAR_FOUND_END_NODE) {
 		if (aystar->FoundEndNode != NULL)
 			aystar->FoundEndNode(aystar, current);
 		free(current);
diff --git a/aystar.h b/aystar.h
index 037954d32..dab6b81e8 100644
--- a/aystar.h
+++ b/aystar.h
@@ -56,7 +56,7 @@ typedef struct AyStar AyStar;
  *	AYSTAR_FOUND_END_NODE : indicates this is the end tile
  *	AYSTAR_DONE : indicates this is not the end tile (or direction was wrong)
  */
-typedef int32 AyStar_EndNodeCheck(AyStar *aystar, OpenListNode *current);
+typedef int32 AyStar_EndNodeCheck(AyStar *aystar, AyStarNode *node);
 
 /*
  * This function is called to calculate the G-value for AyStar Algorithm.
diff --git a/npf.c b/npf.c
index 3ca44c102..ab7cdb5a9 100644
--- a/npf.c
+++ b/npf.c
@@ -341,19 +341,30 @@ int32 NPFRailPathCost(AyStar* as, AyStarNode* current, OpenListNode* parent) {
 
 	/* Determine extra costs */
 
-	/* Ordinary track with signals */
+	/* Check for signals */
 	if (IsTileType(tile, MP_RAILWAY) && (_map5[tile] & 0xC0) == 0x40) {
+		/* Ordinary track with signals */
 		if ((_map2[tile] & _signal_along_trackdir[trackdir]) == 0) {
 			/* Signal facing us is red */
-			if (!(current->user_data[NPF_NODE_FLAGS] & NPF_FLAG_SEEN_SIGNAL)) {
+			if (!NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {
 				/* Penalize the first signal we
 				 * encounter, if it is red */
 				cost += _patches.npf_rail_firstred_penalty;
 			}
+			/* Record the state of this signal */
+			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, true);
+		} else {
+			/* Record the state of this signal */
+			NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, false);
 		}
-		current->user_data[NPF_NODE_FLAGS] |= NPF_FLAG_SEEN_SIGNAL;
+		NPFSetFlag(current, NPF_FLAG_SEEN_SIGNAL, true);
 	}
 
+	/* Penalise the tile if it is a target tile and the last signal was
+	 * red */
+	if (as->EndNodeCheck(as, current) && NPFGetFlag(current, NPF_FLAG_LAST_SIGNAL_RED))
+		cost += _patches.npf_rail_lastred_penalty;
+
 	/* Check for slope */
 	cost += NPFSlopeCost(current);
 
@@ -385,8 +396,8 @@ int32 NPFRailPathCost(AyStar* as, AyStarNode* current, OpenListNode* parent) {
 }
 
 /* Will find any depot */
-int32 NPFFindDepot(AyStar* as, OpenListNode *current) {
-	TileIndex tile = current->path.node.tile;
+int32 NPFFindDepot(AyStar* as, AyStarNode *node) {
+	TileIndex tile = node->tile;
 	if (IsTileDepotType(tile, as->user_data[NPF_TYPE]))
 		return AYSTAR_FOUND_END_NODE;
 	else
@@ -394,17 +405,28 @@ int32 NPFFindDepot(AyStar* as, OpenListNode *current) {
 }
 
 /* Will find a station identified using the NPFFindStationOrTileData */
-int32 NPFFindStationOrTile(AyStar* as, OpenListNode *current) {
+int32 NPFFindStationOrTile(AyStar* as, AyStarNode *node) {
+
+	/* See if we checked this before */
+	if (NPFGetFlag(node, NPF_FLAG_TARGET_CHECKED))
+		return NPFGetFlag(node, NPF_FLAG_IS_TARGET);
+	/* We're gonna check this now and store the result, let's mark that */
+	NPFSetFlag(node, NPF_FLAG_TARGET_CHECKED, true);
+
 	/* If GetNeighbours said we could get here, we assume the station type
 	 * is correct */
 	NPFFindStationOrTileData* fstd = (NPFFindStationOrTileData*)as->user_target;
-	TileIndex tile = current->path.node.tile;
-	if (	(fstd->station_index == -1 && tile == fstd->dest_coords) || /* We've found the tile, or */
+	TileIndex tile = node->tile;
+	if (
+		(fstd->station_index == -1 && tile == fstd->dest_coords) || /* We've found the tile, or */
 		(IsTileType(tile, MP_STATION) && _map2[tile] == fstd->station_index) /* the station */
-	   )
-			return AYSTAR_FOUND_END_NODE;
-	else
+	) {
+		NPFSetFlag(node, NPF_FLAG_TARGET_CHECKED, true);
+		return AYSTAR_FOUND_END_NODE;
+	} else {
+		NPFSetFlag(node, NPF_FLAG_TARGET_CHECKED, false);
 		return AYSTAR_DONE;
+	}
 }
 
 /* To be called when current contains the (shortest route to) the target node.
@@ -422,9 +444,9 @@ void NPFSaveTargetData(AyStar* as, OpenListNode* current) {
 /* Will just follow the results of GetTileTrackStatus concerning where we can
  * go and where not. Uses AyStar.user_data[NPF_TYPE] as the transport type and
  * an argument to GetTileTrackStatus. Will skip tunnels, meaning that the
- * entry and exit are neighbours. Will fill AyStarNode.user_data[NPF_TRACKDIR_CHOICE] with an
- * appropriate value, and copy AyStarNode.user_data[NPF_NODE_FLAGS] from the
- * parent */
+ * entry and exit are neighbours. Will fill
+ * AyStarNode.user_data[NPF_TRACKDIR_CHOICE] with an appropriate value, and
+ * copy AyStarNode.user_data[NPF_NODE_FLAGS] from the parent */
 void NPFFollowTrack(AyStar* aystar, OpenListNode* current) {
 	byte src_trackdir = current->path.node.direction;
 	TileIndex src_tile = current->path.node.tile;
@@ -581,7 +603,8 @@ NPFFoundTargetData NPFRouteInternal(AyStarNode* start1, AyStarNode* start2, NPFF
 	_npf_aystar.addstart(&_npf_aystar, start1);
 	if (start2) {
 		start2->user_data[NPF_TRACKDIR_CHOICE] = 0xff;
-		start2->user_data[NPF_NODE_FLAGS] = NPF_FLAG_REVERSE;
+		start2->user_data[NPF_NODE_FLAGS] = 0;
+		NPFSetFlag(start2, NPF_FLAG_REVERSE, true);
 		_npf_aystar.addstart(&_npf_aystar, start2);
 	}
 
diff --git a/npf.h b/npf.h
index 1444cbe73..be2fb95c1 100644
--- a/npf.h
+++ b/npf.h
@@ -23,10 +23,18 @@ enum { /* Indices into AyStarNode.userdata[] */
 	NPF_TRACKDIR_CHOICE = 0, /* The trackdir chosen to get here */
 	NPF_NODE_FLAGS,
 };
-enum { /* Flags for AyStarNode.userdata[NPF_NODE_FLAGS]*/
-	NPF_FLAG_SEEN_SIGNAL = 1, /* Used to mark that a signal was seen on the way, for rail only */
-	NPF_FLAG_REVERSE = 2, /* Used to mark that this node was reached from the second start node, if applicable */
-};
+typedef enum { /* Flags for AyStarNode.userdata[NPF_NODE_FLAGS]. Use NPFGetBit() and NPFGetBit() to use them. */
+	NPF_FLAG_SEEN_SIGNAL, /* Used to mark that a signal was seen on the way, for rail only */
+	NPF_FLAG_REVERSE, /* Used to mark that this node was reached from the second start node, if applicable */
+	NPF_FLAG_LAST_SIGNAL_RED, /* Used to mark that the last signal on this path was red */
+	NPF_FLAG_TARGET_CHECKED, /* Used by end node checking function of npf to mark
+														 that they have evaluated this node. When this
+														 flag is on, NPF_FLAG_IS_TARGET is on when the
+														 node is a target, and off when it is not. Should
+														 never be used directly, only by the end node
+														 checking functions for caching of results. */
+	NPF_FLAG_IS_TARGET, /* See comment for NPF_FLAG_TARGET_CHECKED */
+} NPFNodeFlag;
 
 typedef struct NPFFoundTargetData { /* Meant to be stored in AyStar.userpath */
 	uint best_bird_dist; /* The best heuristic found. Is 0 if the target was found */
@@ -42,8 +50,8 @@ typedef struct NPFFoundTargetData { /* Meant to be stored in AyStar.userpath */
  * NPFFoundTargetData above for the meaning of the result. */
 NPFFoundTargetData NPFRouteToStationOrTile(TileIndex tile, byte trackdir, NPFFindStationOrTileData* target, TransportType type, Owner owner);
 /* Will search as above, but with two start nodes, the second being the
- * reverse. Look at the NPF_NODE_REVERSE flag in the result node to see which
- * direction was taken */
+ * reverse. Look at the NPF_FLAG_REVERSE flag in the result node to see which
+ * direction was taken (NPFGetBit(result.node, NPF_FLAG_REVERSE)) */
 NPFFoundTargetData NPFRouteToStationOrTileTwoWay(TileIndex tile1, byte trackdir1, TileIndex tile2, byte trackdir2, NPFFindStationOrTileData* target, TransportType type, Owner owner);
 
 /* Will search a route to the closest depot. */
@@ -57,6 +65,30 @@ NPFFoundTargetData NPFRouteToDepotTrialError(TileIndex tile, byte trackdir, Tran
 
 void NPFFillWithOrderData(NPFFindStationOrTileData* fstd, Vehicle* v);
 
+
+/*
+ * Functions to manipulate the various NPF related flags on an AyStarNode.
+ */
+
+/**
+ * Returns the current value of the given flag on the given AyStarNode.
+ */
+static inline bool NPFGetFlag(const AyStarNode* node, NPFNodeFlag flag)
+{
+	return HASBIT(node->user_data[NPF_NODE_FLAGS], flag);
+}
+
+/**
+ * Sets the given flag on the given AyStarNode to the given value.
+ */
+static inline void NPFSetFlag(AyStarNode* node, NPFNodeFlag flag, bool value)
+{
+	if (value)
+		SETBIT(node->user_data[NPF_NODE_FLAGS], flag);
+	else
+		CLRBIT(node->user_data[NPF_NODE_FLAGS], flag);
+}
+
 /*
  * Some tables considering tracks, directions and signals.
  * XXX: Better place to but these?
diff --git a/settings.c b/settings.c
index f82508440..ebd2eea3c 100644
--- a/settings.c
+++ b/settings.c
@@ -933,6 +933,13 @@ const SettingDesc patch_settings[] = {
 	* sure), so we set the default penalty at 10 (the station tile
 	* penalty will further prevent this */
 	{"npf_rail_firstred_penalty",		SDT_UINT32, (void*)(10 * NPF_TILE_LENGTH),	&_patches.npf_rail_firstred_penalty,		NULL},
+	/* This penalty is for when the last signal before the target is red.
+	 * This is useful for train stations, where there are multiple
+	 * platforms to choose from, which lie in different signal blocks.
+	 * Every target in a occupied signal block (ie an occupied platform)
+	 * will get this penalty.
+	 */
+	{"npf_rail_lastred_penalty",		SDT_UINT32, (void*)(10 * NPF_TILE_LENGTH),	&_patches.npf_rail_lastred_penalty,		NULL},
 	/* When a train plans a route over a station tile, this penalty is
 	* applied. We want that trains plan a route around a typical, 4x5
 	* station, which means two tiles to the right, and two tiles back to
diff --git a/train_cmd.c b/train_cmd.c
index 683022538..99a499765 100644
--- a/train_cmd.c
+++ b/train_cmd.c
@@ -1143,7 +1143,7 @@ static void ReverseTrainDirection(Vehicle *v)
 	{
 		TileIndex tile = v->tile;
 		int t;
-		/* Determine the non-diagonal direction in which we will exit this tile */
+		/* Determine the diagonal direction in which we will exit this tile */
 		t = v->direction >> 1;
 		if (!(v->direction & 1) && v->u.rail.track != _state_dir_table[t]) {
 			t = (t - 1) & 3;
diff --git a/variables.h b/variables.h
index 1f7dbf587..ecc525749 100644
--- a/variables.h
+++ b/variables.h
@@ -193,6 +193,7 @@ typedef struct Patches {
 	bool new_pathfinding_all; /* Use the newest pathfinding algorithm for all */
 
 	uint32 npf_rail_firstred_penalty; /* The penalty for when the first signal is red */
+	uint32 npf_rail_lastred_penalty; /* The penalty for when the last signal is red */
 	uint32 npf_rail_station_penalty; /* The penalty for station tiles */
 	uint32 npf_rail_slope_penalty; /* The penalty for sloping upwards */