From c1b371b510f668e2d6e5e25f7ffc619a095d8c2e Mon Sep 17 00:00:00 2001
From: zaxcav <daveanti@gmail.com>
Date: Wed, 28 Sep 2016 21:45:49 +0200
Subject: [PATCH] Pathfinding now only treats wide path tiles as continuing
 tiles (and therefore a valid search result) when the current path tile is
 also wide.

Wide tiles are consequently only traversed to reach thin path tiles when in an area of wide path tiles. This fixes peeps getting stuck when the path search limits are all further away from the destination than wide tiles.
---
 src/peep/peep.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/src/peep/peep.c b/src/peep/peep.c
index a5a6a06a87..c38fcb9946 100644
--- a/src/peep/peep.c
+++ b/src/peep/peep.c
@@ -8748,7 +8748,7 @@ static bool path_is_thin_junction(rct_map_element *path, sint16 x, sint16 y, uin
  *
  *  rct2: 0x0069A997
  */
-static uint8 peep_pathfind_heuristic_search(sint16 x, sint16 y, uint8 z, uint8 counter, uint16 *endScore, int test_edge, uint8 *endJunctions, rct_xyz8 junctionList[16], uint8 directionList[16], rct_xyz8 *endXYZ, uint8 *endSteps) {
+static uint8 peep_pathfind_heuristic_search(sint16 x, sint16 y, uint8 z, rct_map_element *currentMapElement, uint8 counter, uint16 *endScore, int test_edge, uint8 *endJunctions, rct_xyz8 junctionList[16], uint8 directionList[16], rct_xyz8 *endXYZ, uint8 *endSteps) {
 	uint searchResult = PATH_SEARCH_FAILED;
 
 	x += TileDirectionDelta[test_edge].x;
@@ -8956,14 +8956,16 @@ static uint8 peep_pathfind_heuristic_search(sint16 x, sint16 y, uint8 z, uint8 c
 
 	/* At this point the map element is a path. */
 
-	/* If this is a wide path the search ends here but the goal
-	 * could still be reachable from here.
-	 * Return the searchResult with the new score. */
+	/* If this is a wide path the search ends here. */
 	if (searchResult == PATH_SEARCH_WIDE) {
 		/* Ignore Wide paths as continuing paths UNLESS the current path is also Wide.
 		 * i.e. search across wide paths from a wide path to get onto a thin path,
 		 * thereafter stay on thin paths. */
-		if (false) { // TODO: Check that the current tile is also Wide.
+		/* So, if the current path is also wide the goal could still
+		 * be reachable from here.
+		 * Return the searchResult with the new score.
+		 * Otherwise, return the original score. */
+		if (footpath_element_is_wide(currentMapElement)) {
 			*endScore = new_score;
 			*endSteps = counter;
 			// Update the end x,y,z
@@ -9143,7 +9145,7 @@ static uint8 peep_pathfind_heuristic_search(sint16 x, sint16 y, uint8 z, uint8 c
 		memset(directionList, 0x00, sizeof(directionList[16]));
 		memset(endXYZ, 0x00, sizeof(*endXYZ));
 
-		uint8 continueResult = peep_pathfind_heuristic_search(x, y, height, counter, endScore, test_edge, endJunctions, junctionList, directionList, endXYZ, endSteps);
+		uint8 continueResult = peep_pathfind_heuristic_search(x, y, height, mapElement, counter, endScore, test_edge, endJunctions, junctionList, directionList, endXYZ, endSteps);
 		_peepPathFindNumJunctions = savedNumJunctions;
 
 		if (continueResult == PATH_SEARCH_LIMIT_REACHED) {
@@ -9409,7 +9411,7 @@ int peep_pathfind_choose_direction(sint16 x, sint16 y, uint8 z, rct_peep *peep)
 			uint8 endDirectionList[16];
 			memset(endDirectionList, 0x0, sizeof(endDirectionList));
 
-			uint8 searchResult = peep_pathfind_heuristic_search(x, y, height, 0, &score, test_edge, &endJunctions, endJunctionList, endDirectionList, &endXYZ, &endSteps);
+			uint8 searchResult = peep_pathfind_heuristic_search(x, y, height, dest_map_element, 0, &score, test_edge, &endJunctions, endJunctionList, endDirectionList, &endXYZ, &endSteps);
 			#if defined(DEBUG_LEVEL_1) && DEBUG_LEVEL_1
 			if (gPathFindDebug) {
 				log_verbose("Pathfind test edge: %d score: %d steps: %d searchResult: %s end: %d,%d,%d junctions: %d", test_edge, score, endSteps, gPathFindSearchText[searchResult], endXYZ.x, endXYZ.y, endXYZ.z, endJunctions);
@@ -9422,7 +9424,7 @@ int peep_pathfind_choose_direction(sint16 x, sint16 y, uint8 z, rct_peep *peep)
 			if (score == 0 ||
 				searchResult == PATH_SEARCH_THIN ||
 				searchResult == PATH_SEARCH_JUNCTION ||
-				(searchResult == PATH_SEARCH_WIDE && false)) { // TODO: Here check that the current tile is also Wide
+				searchResult == PATH_SEARCH_WIDE) {
 				if (score < best_score || (score == best_score && endSteps < best_sub)) {
 					chosen_edge = test_edge;
 					best_score = score;