truelight@2381: /* $Id$ */
truelight@2381: 
truelight@2381: #include "../../stdafx.h"
truelight@2381: #include "../../openttd.h"
tron@3234: #include "../../bridge_map.h"
truelight@2381: #include "../../debug.h"
truelight@2381: #include "../../functions.h"
truelight@2381: #include "../../map.h"
truelight@2381: #include "../../tile.h"
truelight@2381: #include "../../command.h"
truelight@2381: #include "trolly.h"
truelight@2381: #include "../../depot.h"
tron@3179: #include "../../tunnel_map.h"
celestar@3359: #include "../../bridge.h"
truelight@2682: #include "../ai.h"
truelight@2381: 
truelight@2381: #define TEST_STATION_NO_DIR 0xFF
truelight@2381: 
truelight@2381: // Tests if a station can be build on the given spot
truelight@2381: // TODO: make it train compatible
truelight@2381: static bool TestCanBuildStationHere(TileIndex tile, byte dir)
truelight@2381: {
truelight@2381: 	Player *p = GetPlayer(_current_player);
truelight@2381: 
truelight@2381: 	if (dir == TEST_STATION_NO_DIR) {
truelight@2381: 		int32 ret;
truelight@2381: 		// TODO: currently we only allow spots that can be access from al 4 directions...
truelight@2381: 		//  should be fixed!!!
truelight@2381: 		for (dir = 0; dir < 4; dir++) {
truelight@2381: 			ret = AiNew_Build_Station(p, p->ainew.tbt, tile, 1, 1, dir, DC_QUERY_COST);
truelight@2381: 			if (!CmdFailed(ret)) return true;
truelight@2381: 		}
truelight@2381: 		return false;
truelight@2381: 	}
truelight@2381: 
truelight@2381: 	// return true if command succeeded, so the inverse of CmdFailed()
truelight@2381: 	return !CmdFailed(AiNew_Build_Station(p, p->ainew.tbt, tile, 1, 1, dir, DC_QUERY_COST));
truelight@2381: }
truelight@2381: 
truelight@2381: 
truelight@2381: static bool IsRoad(TileIndex tile)
truelight@2381: {
truelight@2381: 	return
truelight@2381: 		// MP_STREET, but not a road depot?
truelight@2381: 		(IsTileType(tile, MP_STREET) && !IsTileDepotType(tile, TRANSPORT_ROAD)) ||
truelight@2381: 		(IsTileType(tile, MP_TUNNELBRIDGE) && (
tron@3184: 			(IsTunnel(tile) && GetTunnelTransportType(tile) == TRANSPORT_ROAD) ||
tron@3234: 			(IsBridge(tile) && GetBridgeTransportType(tile) == TRANSPORT_ROAD)
truelight@2381: 		));
truelight@2381: }
truelight@2381: 
truelight@2381: 
truelight@2381: // Checks if a tile 'a' is between the tiles 'b' and 'c'
truelight@2381: #define TILES_BETWEEN(a, b, c) (TileX(a) >= TileX(b) && TileX(a) <= TileX(c) && TileY(a) >= TileY(b) && TileY(a) <= TileY(c))
truelight@2381: 
truelight@2381: 
truelight@2381: // Check if the current tile is in our end-area
truelight@2381: static int32 AyStar_AiPathFinder_EndNodeCheck(AyStar *aystar, OpenListNode *current)
truelight@2381: {
truelight@2381: 	Ai_PathFinderInfo *PathFinderInfo = (Ai_PathFinderInfo*)aystar->user_target;
truelight@2381: 	// It is not allowed to have a station on the end of a bridge or tunnel ;)
truelight@2381: 	if (current->path.node.user_data[0] != 0) return AYSTAR_DONE;
truelight@2381: 	if (TILES_BETWEEN(current->path.node.tile, PathFinderInfo->end_tile_tl, PathFinderInfo->end_tile_br))
truelight@2381: 		if (IsTileType(current->path.node.tile, MP_CLEAR) || IsTileType(current->path.node.tile, MP_TREES))
truelight@2381: 			if (current->path.parent == NULL || TestCanBuildStationHere(current->path.node.tile, AiNew_GetDirection(current->path.parent->node.tile, current->path.node.tile)))
truelight@2381: 				return AYSTAR_FOUND_END_NODE;
truelight@2381: 
truelight@2381: 	return AYSTAR_DONE;
truelight@2381: }
truelight@2381: 
truelight@2381: 
truelight@2381: // Calculates the hash
truelight@2381: //   Currently it is a 10 bit hash, so the hash array has a max depth of 6 bits (so 64)
truelight@2381: static uint AiPathFinder_Hash(uint key1, uint key2)
truelight@2381: {
truelight@2381: 	return (TileX(key1) & 0x1F) + ((TileY(key1) & 0x1F) << 5);
truelight@2381: }
truelight@2381: 
truelight@2381: 
truelight@2381: // Clear the memory of all the things
truelight@2381: static void AyStar_AiPathFinder_Free(AyStar *aystar)
truelight@2381: {
truelight@2381: 	AyStarMain_Free(aystar);
truelight@2381: 	free(aystar);
truelight@2381: }
truelight@2381: 
truelight@2381: 
truelight@2381: static int32 AyStar_AiPathFinder_CalculateG(AyStar *aystar, AyStarNode *current, OpenListNode *parent);
truelight@2381: static int32 AyStar_AiPathFinder_CalculateH(AyStar *aystar, AyStarNode *current, OpenListNode *parent);
truelight@2381: static void AyStar_AiPathFinder_FoundEndNode(AyStar *aystar, OpenListNode *current);
truelight@2381: static void AyStar_AiPathFinder_GetNeighbours(AyStar *aystar, OpenListNode *current);
truelight@2381: 
truelight@2381: 
truelight@2381: // This creates the AiPathFinder
truelight@2381: AyStar *new_AyStar_AiPathFinder(int max_tiles_around, Ai_PathFinderInfo *PathFinderInfo)
truelight@2381: {
truelight@2381: 	PathNode start_node;
truelight@2381: 	uint x;
truelight@2381: 	uint y;
truelight@2381: 	// Create AyStar
truelight@2381: 	AyStar *result = malloc(sizeof(AyStar));
truelight@2381: 	init_AyStar(result, AiPathFinder_Hash, 1 << 10);
truelight@2381: 	// Set the function pointers
truelight@2381: 	result->CalculateG = AyStar_AiPathFinder_CalculateG;
truelight@2381: 	result->CalculateH = AyStar_AiPathFinder_CalculateH;
truelight@2381: 	result->EndNodeCheck = AyStar_AiPathFinder_EndNodeCheck;
truelight@2381: 	result->FoundEndNode = AyStar_AiPathFinder_FoundEndNode;
truelight@2381: 	result->GetNeighbours = AyStar_AiPathFinder_GetNeighbours;
truelight@2381: 
truelight@2381: 	result->free = AyStar_AiPathFinder_Free;
truelight@2381: 
truelight@2381: 	// Set some information
truelight@2381: 	result->loops_per_tick = AI_PATHFINDER_LOOPS_PER_TICK;
truelight@2381: 	result->max_path_cost = 0;
truelight@2381: 	result->max_search_nodes = AI_PATHFINDER_MAX_SEARCH_NODES;
truelight@2381: 
truelight@2381: 	// Set the user_data to the PathFinderInfo
truelight@2381: 	result->user_target = PathFinderInfo;
truelight@2381: 
truelight@2381: 	// Set the start node
truelight@2381: 	start_node.parent = NULL;
truelight@2381: 	start_node.node.direction = 0;
truelight@2381: 	start_node.node.user_data[0] = 0;
truelight@2381: 
truelight@2381: 	// Now we add all the starting tiles
truelight@2381: 	for (x = TileX(PathFinderInfo->start_tile_tl); x <= TileX(PathFinderInfo->start_tile_br); x++) {
truelight@2381: 		for (y = TileY(PathFinderInfo->start_tile_tl); y <= TileY(PathFinderInfo->start_tile_br); y++) {
truelight@2381: 			start_node.node.tile = TileXY(x, y);
truelight@2381: 			result->addstart(result, &start_node.node, 0);
truelight@2381: 		}
truelight@2381: 	}
truelight@2381: 
truelight@2381: 	return result;
truelight@2381: }
truelight@2381: 
truelight@2381: 
truelight@2381: // To reuse AyStar we sometimes have to clean all the memory
truelight@2381: void clean_AyStar_AiPathFinder(AyStar *aystar, Ai_PathFinderInfo *PathFinderInfo)
truelight@2381: {
truelight@2381: 	PathNode start_node;
truelight@2381: 	uint x;
truelight@2381: 	uint y;
truelight@2381: 
truelight@2381: 	aystar->clear(aystar);
truelight@2381: 
truelight@2381: 	// Set the user_data to the PathFinderInfo
truelight@2381: 	aystar->user_target = PathFinderInfo;
truelight@2381: 
truelight@2381: 	// Set the start node
truelight@2381: 	start_node.parent = NULL;
truelight@2381: 	start_node.node.direction = 0;
truelight@2381: 	start_node.node.user_data[0] = 0;
truelight@2381: 	start_node.node.tile = PathFinderInfo->start_tile_tl;
truelight@2381: 
truelight@2381: 	// Now we add all the starting tiles
truelight@2381: 	for (x = TileX(PathFinderInfo->start_tile_tl); x <= TileX(PathFinderInfo->start_tile_br); x++) {
truelight@2381: 		for (y = TileY(PathFinderInfo->start_tile_tl); y <= TileY(PathFinderInfo->start_tile_br); y++) {
truelight@2381: 			if (!(IsTileType(TileXY(x, y), MP_CLEAR) || IsTileType(TileXY(x, y), MP_TREES))) continue;
truelight@2381: 			if (!TestCanBuildStationHere(TileXY(x, y), TEST_STATION_NO_DIR)) continue;
truelight@2381: 			start_node.node.tile = TileXY(x, y);
truelight@2381: 			aystar->addstart(aystar, &start_node.node, 0);
truelight@2381: 		}
truelight@2381: 	}
truelight@2381: }
truelight@2381: 
truelight@2381: 
truelight@2381: // The h-value, simple calculation
truelight@2381: static int32 AyStar_AiPathFinder_CalculateH(AyStar *aystar, AyStarNode *current, OpenListNode *parent)
truelight@2381: {
truelight@2381: 	Ai_PathFinderInfo *PathFinderInfo = (Ai_PathFinderInfo*)aystar->user_target;
truelight@2381: 	int r, r2;
truelight@2381: 	if (PathFinderInfo->end_direction != AI_PATHFINDER_NO_DIRECTION) {
truelight@2381: 		// The station is pointing to a direction, add a tile towards that direction, so the H-value is more accurate
truelight@2381: 		r = DistanceManhattan(current->tile, PathFinderInfo->end_tile_tl + TileOffsByDir(PathFinderInfo->end_direction));
truelight@2381: 		r2 = DistanceManhattan(current->tile, PathFinderInfo->end_tile_br + TileOffsByDir(PathFinderInfo->end_direction));
truelight@2381: 	} else {
truelight@2381: 		// No direction, so just get the fastest route to the station
truelight@2381: 		r = DistanceManhattan(current->tile, PathFinderInfo->end_tile_tl);
truelight@2381: 		r2 = DistanceManhattan(current->tile, PathFinderInfo->end_tile_br);
truelight@2381: 	}
truelight@2381: 	// See if the bottomright is faster than the topleft..
truelight@2381: 	if (r2 < r) r = r2;
truelight@2381: 	return r * AI_PATHFINDER_H_MULTIPLER;
truelight@2381: }
truelight@2381: 
truelight@2381: 
truelight@2381: // We found the end.. let's get the route back and put it in an array
truelight@2381: static void AyStar_AiPathFinder_FoundEndNode(AyStar *aystar, OpenListNode *current)
truelight@2381: {
truelight@2381: 	Ai_PathFinderInfo *PathFinderInfo = (Ai_PathFinderInfo*)aystar->user_target;
truelight@2381: 	uint i = 0;
truelight@2381: 	PathNode *parent = &current->path;
truelight@2381: 
truelight@2381: 	do {
truelight@2381: 		PathFinderInfo->route_extra[i] = parent->node.user_data[0];
truelight@2381: 		PathFinderInfo->route[i++] = parent->node.tile;
truelight@2381: 		if (i > lengthof(PathFinderInfo->route)) {
truelight@2381: 			// We ran out of space for the PathFinder
truelight@2381: 			DEBUG(ai, 0)("[AiPathFinder] Ran out of space in the route[] array!!!");
truelight@2381: 			PathFinderInfo->route_length = -1; // -1 indicates out of space
truelight@2381: 			return;
truelight@2381: 		}
truelight@2381: 		parent = parent->parent;
truelight@2381: 	} while (parent != NULL);
truelight@2381: 	PathFinderInfo->route_length = i;
truelight@2381: 	DEBUG(ai, 1)("[Ai-PathFinding] Found route of %d nodes long in %d nodes of searching", i, Hash_Size(&aystar->ClosedListHash));
truelight@2381: }
truelight@2381: 
truelight@2381: 
truelight@2381: // What tiles are around us.
truelight@2381: static void AyStar_AiPathFinder_GetNeighbours(AyStar *aystar, OpenListNode *current)
truelight@2381: {
truelight@2381: 	uint i;
truelight@2381: 	int ret;
truelight@2381: 	int dir;
truelight@2381: 
truelight@2381: 	Ai_PathFinderInfo *PathFinderInfo = (Ai_PathFinderInfo*)aystar->user_target;
truelight@2381: 
truelight@2381: 	aystar->num_neighbours = 0;
truelight@2381: 
truelight@2381: 	// Go through all surrounding tiles and check if they are within the limits
truelight@2381: 	for (i = 0; i < 4; i++) {
truelight@2381: 		TileIndex ctile = current->path.node.tile; // Current tile
truelight@2381: 		TileIndex atile = ctile + TileOffsByDir(i); // Adjacent tile
truelight@2381: 
truelight@2381: 		if (TileX(atile) > 1 && TileX(atile) < MapMaxX() - 1 &&
truelight@2381: 				TileY(atile) > 1 && TileY(atile) < MapMaxY() - 1) {
truelight@2381: 			// We also directly test if the current tile can connect to this tile..
truelight@2381: 			//  We do this simply by just building the tile!
truelight@2381: 
truelight@2381: 			// If the next step is a bridge, we have to enter it the right way
truelight@2381: 			if (!PathFinderInfo->rail_or_road && IsRoad(atile)) {
truelight@2381: 				if (IsTileType(atile, MP_TUNNELBRIDGE)) {
tron@3184: 					if (IsTunnel(atile)) {
tron@3179: 						if (GetTunnelDirection(atile) != i) continue;
tron@3184: 					} else {
tron@3484: 						if ((_m[atile].m5 & 1U) != DiagDirToAxis(i)) continue;
truelight@2381: 					}
truelight@2381: 				}
truelight@2381: 			}
truelight@2381: 			// But also if we are on a bridge, we can only move a certain direction
truelight@2381: 			if (!PathFinderInfo->rail_or_road && IsRoad(ctile)) {
truelight@2381: 				if (IsTileType(ctile, MP_TUNNELBRIDGE)) {
truelight@2381: 					// An existing bridge/tunnel... let's test the direction ;)
truelight@2381: 					if ((_m[ctile].m5 & 1U) != (i & 1)) continue;
truelight@2381: 				}
truelight@2381: 			}
truelight@2381: 
truelight@2381: 			if ((AI_PATHFINDER_FLAG_BRIDGE & current->path.node.user_data[0]) != 0 ||
truelight@2381: 					(AI_PATHFINDER_FLAG_TUNNEL & current->path.node.user_data[0]) != 0) {
truelight@2381: 				// We are a bridge/tunnel, how cool!!
truelight@2381: 				//  This means we can only point forward.. get the direction from the user_data
truelight@2381: 				if (i != (current->path.node.user_data[0] >> 8)) continue;
truelight@2381: 			}
truelight@2381: 			dir = 0;
truelight@2381: 
truelight@2381: 			// First, check if we have a parent
truelight@2381: 			if (current->path.parent == NULL && current->path.node.user_data[0] == 0) {
truelight@2381: 				// If not, this means we are at the starting station
truelight@2381: 				if (PathFinderInfo->start_direction != AI_PATHFINDER_NO_DIRECTION) {
truelight@2381: 					// We do need a direction?
truelight@2381: 					if (AiNew_GetDirection(ctile, atile) != PathFinderInfo->start_direction) {
truelight@2381: 						// We are not pointing the right way, invalid tile
truelight@2381: 						continue;
truelight@2381: 					}
truelight@2381: 				}
truelight@2381: 			} else if (current->path.node.user_data[0] == 0) {
truelight@2381: 				if (PathFinderInfo->rail_or_road) {
truelight@2381: 					// Rail check
truelight@2381: 					dir = AiNew_GetRailDirection(current->path.parent->node.tile, ctile, atile);
truelight@2682: 					ret = AI_DoCommand(ctile, 0, dir, DC_AUTO | DC_NO_WATER, CMD_BUILD_SINGLE_RAIL);
truelight@2381: 					if (CmdFailed(ret)) continue;
truelight@2381: #ifdef AI_PATHFINDER_NO_90DEGREES_TURN
truelight@2381: 					if (current->path.parent->parent != NULL) {
truelight@2381: 						// Check if we don't make a 90degree curve
truelight@2381: 						int dir1 = AiNew_GetRailDirection(current->path.parent->parent->node.tile, current->path.parent->node.tile, ctile);
truelight@2381: 						if (_illegal_curves[dir1] == dir || _illegal_curves[dir] == dir1) {
truelight@2381: 							continue;
truelight@2381: 						}
truelight@2381: 					}
truelight@2381: #endif
truelight@2381: 				} else {
truelight@2381: 					// Road check
truelight@2381: 					dir = AiNew_GetRoadDirection(current->path.parent->node.tile, ctile, atile);
truelight@2381: 					if (IsRoad(ctile)) {
truelight@2381: 						if (IsTileType(ctile, MP_TUNNELBRIDGE)) {
truelight@2381: 							// We have a bridge, how nicely! We should mark it...
truelight@2381: 							dir = 0;
truelight@2381: 						} else {
truelight@2381: 							// It already has road.. check if we miss any bits!
truelight@2381: 							if ((_m[ctile].m5 & dir) != dir) {
truelight@2381: 								// We do miss some pieces :(
truelight@2381: 								dir &= ~_m[ctile].m5;
truelight@2381: 							} else {
truelight@2381: 								dir = 0;
truelight@2381: 							}
truelight@2381: 						}
truelight@2381: 					}
truelight@2381: 					// Only destruct things if it is MP_CLEAR of MP_TREES
truelight@2381: 					if (dir != 0) {
truelight@2682: 						ret = AI_DoCommand(ctile, dir, 0, DC_AUTO | DC_NO_WATER, CMD_BUILD_ROAD);
truelight@2381: 						if (CmdFailed(ret)) continue;
truelight@2381: 					}
truelight@2381: 				}
truelight@2381: 			}
truelight@2381: 
truelight@2381: 			// The tile can be connected
truelight@2381: 			aystar->neighbours[aystar->num_neighbours].tile = atile;
truelight@2381: 			aystar->neighbours[aystar->num_neighbours].user_data[0] = 0;
truelight@2381: 			aystar->neighbours[aystar->num_neighbours++].direction = 0;
truelight@2381: 		}
truelight@2381: 	}
truelight@2381: 
truelight@2381: 	// Next step, check for bridges and tunnels
truelight@2381: 	if (current->path.parent != NULL && current->path.node.user_data[0] == 0) {
truelight@2381: 		// First we get the dir from this tile and his parent
tron@3644: 		DiagDirection dir = AiNew_GetDirection(current->path.parent->node.tile, current->path.node.tile);
truelight@2381: 		// It means we can only walk with the track, so the bridge has to be in the same direction
truelight@2381: 		TileIndex tile = current->path.node.tile;
truelight@2381: 		TileIndex new_tile = tile;
tron@3644: 		Slope tileh = GetTileSlope(tile, NULL);
truelight@2381: 
truelight@2381: 		// Bridges can only be build on land that is not flat
truelight@2381: 		//  And if there is a road or rail blocking
tron@3644: 		if (tileh != SLOPE_FLAT ||
truelight@2381: 				(PathFinderInfo->rail_or_road && IsTileType(tile + TileOffsByDir(dir), MP_STREET)) ||
truelight@2381: 				(!PathFinderInfo->rail_or_road && IsTileType(tile + TileOffsByDir(dir), MP_RAILWAY))) {
truelight@2381: 			for (;;) {
truelight@2381: 				new_tile += TileOffsByDir(dir);
truelight@2381: 
truelight@2381: 				// Precheck, is the length allowed?
truelight@2381: 				if (!CheckBridge_Stuff(0, GetBridgeLength(tile, new_tile))) break;
truelight@2381: 
truelight@2381: 				// Check if we hit the station-tile.. we don't like that!
truelight@2381: 				if (TILES_BETWEEN(new_tile, PathFinderInfo->end_tile_tl, PathFinderInfo->end_tile_br)) break;
truelight@2381: 
truelight@2381: 				// Try building the bridge..
truelight@2682: 				ret = AI_DoCommand(tile, new_tile, (0 << 8) + (MAX_BRIDGES / 2), DC_AUTO, CMD_BUILD_BRIDGE);
truelight@2381: 				if (CmdFailed(ret)) continue;
truelight@2381: 				// We can build a bridge here.. add him to the neighbours
truelight@2381: 				aystar->neighbours[aystar->num_neighbours].tile = new_tile;
truelight@2381: 				aystar->neighbours[aystar->num_neighbours].user_data[0] = AI_PATHFINDER_FLAG_BRIDGE + (dir << 8);
truelight@2381: 				aystar->neighbours[aystar->num_neighbours++].direction = 0;
truelight@2381: 				// We can only have 12 neighbours, and we need 1 left for tunnels
truelight@2381: 				if (aystar->num_neighbours == 11) break;
truelight@2381: 			}
truelight@2381: 		}
truelight@2381: 
truelight@2381: 		// Next, check for tunnels!
tron@3644: 		// Tunnels can only be built on slopes corresponding to the direction
truelight@2381: 		//  For now, we check both sides for this tile.. terraforming gives fuzzy result
tron@3644: 		if ((dir == DIAGDIR_NE && tileh == SLOPE_NE) ||
tron@3644: 				(dir == DIAGDIR_SE && tileh == SLOPE_SE) ||
tron@3644: 				(dir == DIAGDIR_SW && tileh == SLOPE_SW) ||
tron@3644: 				(dir == DIAGDIR_NW && tileh == SLOPE_NW)) {
truelight@2381: 			// Now simply check if a tunnel can be build
truelight@2682: 			ret = AI_DoCommand(tile, (PathFinderInfo->rail_or_road?0:0x200), 0, DC_AUTO, CMD_BUILD_TUNNEL);
tron@3055: 			tileh = GetTileSlope(_build_tunnel_endtile, NULL);
tron@3644: 			if (!CmdFailed(ret) && (tileh == SLOPE_SW || tileh == SLOPE_SE || tileh == SLOPE_NW || tileh == SLOPE_NE)) {
truelight@2381: 				aystar->neighbours[aystar->num_neighbours].tile = _build_tunnel_endtile;
truelight@2381: 				aystar->neighbours[aystar->num_neighbours].user_data[0] = AI_PATHFINDER_FLAG_TUNNEL + (dir << 8);
truelight@2381: 				aystar->neighbours[aystar->num_neighbours++].direction = 0;
truelight@2381: 			}
truelight@2381: 		}
truelight@2381: 	}
truelight@2381: }
truelight@2381: 
truelight@2381: 
tron@3644: extern uint GetRailFoundation(Slope tileh, TrackBits bits); // XXX function declaration in .c
tron@3644: extern uint GetRoadFoundation(Slope tileh, uint bits); // XXX function declaration in .c
tron@3644: extern uint GetBridgeFoundation(Slope tileh, Axis); // XXX function declaration in .c
truelight@2381: enum {
truelight@2381: 	BRIDGE_NO_FOUNDATION = 1 << 0 | 1 << 3 | 1 << 6 | 1 << 9 | 1 << 12,
truelight@2381: };
truelight@2381: 
truelight@2381: // The most important function: it calculates the g-value
truelight@2381: static int32 AyStar_AiPathFinder_CalculateG(AyStar *aystar, AyStarNode *current, OpenListNode *parent)
truelight@2381: {
truelight@2381: 	Ai_PathFinderInfo *PathFinderInfo = (Ai_PathFinderInfo*)aystar->user_target;
truelight@2381: 	int r, res = 0;
tron@3644: 	Slope tileh = GetTileSlope(current->tile, NULL);
tron@3644: 	Slope parent_tileh = GetTileSlope(parent->path.node.tile, NULL);
truelight@2381: 
truelight@2381: 	// Check if we hit the end-tile
truelight@2381: 	if (TILES_BETWEEN(current->tile, PathFinderInfo->end_tile_tl, PathFinderInfo->end_tile_br)) {
truelight@2381: 		// We are at the end-tile, check if we had a direction or something...
truelight@2381: 		if (PathFinderInfo->end_direction != AI_PATHFINDER_NO_DIRECTION && AiNew_GetDirection(current->tile, parent->path.node.tile) != PathFinderInfo->end_direction) {
truelight@2381: 			// We are not pointing the right way, invalid tile
truelight@2381: 			return AYSTAR_INVALID_NODE;
truelight@2381: 		}
truelight@2381: 		// If it was valid, drop out.. we don't build on the endtile
truelight@2381: 		return 0;
truelight@2381: 	}
truelight@2381: 
truelight@2381: 	// Give everything a small penalty
truelight@2381: 	res += AI_PATHFINDER_PENALTY;
truelight@2381: 
truelight@2381: 	if (!PathFinderInfo->rail_or_road) {
truelight@2381: 		// Road has the lovely advantage it can use other road... check if
truelight@2381: 		//  the current tile is road, and if so, give a good bonus
truelight@2381: 		if (IsRoad(current->tile)) {
truelight@2381: 			res -= AI_PATHFINDER_ROAD_ALREADY_EXISTS_BONUS;
truelight@2381: 		}
truelight@2381: 	}
truelight@2381: 
truelight@2381: 	// We should give a penalty when the tile is going up or down.. this is one way to do so!
truelight@2381: 	//  Too bad we have to count it from the parent.. but that is not so bad.
truelight@2381: 	// We also dislike long routes on slopes, since they do not look too realistic
truelight@2381: 	//  when there is a flat land all around, they are more expensive to build, and
truelight@2381: 	//  especially they essentially block the ability to connect or cross the road
truelight@2381: 	//  from one side.
tron@3644: 	if (parent_tileh != SLOPE_FLAT && parent->path.parent != NULL) {
truelight@2381: 		// Skip if the tile was from a bridge or tunnel
truelight@2381: 		if (parent->path.node.user_data[0] == 0 && current->user_data[0] == 0) {
truelight@2381: 			if (PathFinderInfo->rail_or_road) {
tron@3055: 				r = GetRailFoundation(parent_tileh, 1 << AiNew_GetRailDirection(parent->path.parent->node.tile, parent->path.node.tile, current->tile));
truelight@2381: 				// Maybe is BRIDGE_NO_FOUNDATION a bit strange here, but it contains just the right information..
tron@3644: 				if (r >= 15 || (r == 0 && HASBIT(BRIDGE_NO_FOUNDATION, tileh))) {
truelight@2381: 					res += AI_PATHFINDER_TILE_GOES_UP_PENALTY;
truelight@2381: 				} else {
truelight@2381: 					res += AI_PATHFINDER_FOUNDATION_PENALTY;
truelight@2381: 				}
truelight@2381: 			} else {
truelight@2381: 				if (!(IsRoad(parent->path.node.tile) && IsTileType(parent->path.node.tile, MP_TUNNELBRIDGE))) {
tron@3055: 					r = GetRoadFoundation(parent_tileh, AiNew_GetRoadDirection(parent->path.parent->node.tile, parent->path.node.tile, current->tile));
truelight@2381: 					if (r >= 15 || r == 0)
truelight@2381: 						res += AI_PATHFINDER_TILE_GOES_UP_PENALTY;
truelight@2381: 					else
truelight@2381: 						res += AI_PATHFINDER_FOUNDATION_PENALTY;
truelight@2381: 				}
truelight@2381: 			}
truelight@2381: 		}
truelight@2381: 	}
truelight@2381: 
truelight@2381: 	// Are we part of a tunnel?
truelight@2381: 	if ((AI_PATHFINDER_FLAG_TUNNEL & current->user_data[0]) != 0) {
truelight@2381: 		// Tunnels are very expensive when build on long routes..
truelight@2381: 		// Ironicly, we are using BridgeCode here ;)
truelight@2381: 		r = AI_PATHFINDER_TUNNEL_PENALTY * GetBridgeLength(current->tile, parent->path.node.tile);
truelight@2381: 		res += r + (r >> 8);
truelight@2381: 	}
truelight@2381: 
truelight@2381: 	// Are we part of a bridge?
truelight@2381: 	if ((AI_PATHFINDER_FLAG_BRIDGE & current->user_data[0]) != 0) {
truelight@2381: 		// That means for every length a penalty
truelight@2381: 		res += AI_PATHFINDER_BRIDGE_PENALTY * GetBridgeLength(current->tile, parent->path.node.tile);
truelight@2381: 		// Check if we are going up or down, first for the starting point
truelight@2381: 		// In user_data[0] is at the 8th bit the direction
tron@3644: 		if (!HASBIT(BRIDGE_NO_FOUNDATION, parent_tileh)) {
tron@3055: 			if (GetBridgeFoundation(parent_tileh, (current->user_data[0] >> 8) & 1) < 15)
truelight@2381: 				res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;
truelight@2381: 		}
truelight@2381: 		// Second for the end point
tron@3644: 		if (!HASBIT(BRIDGE_NO_FOUNDATION, tileh)) {
tron@3055: 			if (GetBridgeFoundation(tileh, (current->user_data[0] >> 8) & 1) < 15)
truelight@2381: 				res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;
truelight@2381: 		}
tron@3644: 		if (parent_tileh == SLOPE_FLAT) res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;
tron@3644: 		if (tileh == SLOPE_FLAT) res += AI_PATHFINDER_BRIDGE_GOES_UP_PENALTY;
truelight@2381: 	}
truelight@2381: 
truelight@2381: 	//  To prevent the AI from taking the fastest way in tiles, but not the fastest way
truelight@2381: 	//    in speed, we have to give a good penalty to direction changing
truelight@2381: 	//  This way, we get almost the fastest way in tiles, and a very good speed on the track
truelight@2381: 	if (!PathFinderInfo->rail_or_road) {
truelight@2381: 		if (parent->path.parent != NULL &&
truelight@2381: 				AiNew_GetDirection(current->tile, parent->path.node.tile) != AiNew_GetDirection(parent->path.node.tile, parent->path.parent->node.tile)) {
truelight@2381: 			// When road exists, we don't like turning, but its free, so don't be to piggy about it
truelight@2381: 			if (IsRoad(parent->path.node.tile))
truelight@2381: 				res += AI_PATHFINDER_DIRECTION_CHANGE_ON_EXISTING_ROAD_PENALTY;
truelight@2381: 			else
truelight@2381: 				res += AI_PATHFINDER_DIRECTION_CHANGE_PENALTY;
truelight@2381: 		}
truelight@2381: 	} else {
truelight@2381: 		// For rail we have 1 exeption: diagonal rail..
truelight@2381: 		// So we fetch 2 raildirection. That of the current one, and of the one before that
truelight@2381: 		if (parent->path.parent != NULL && parent->path.parent->parent != NULL) {
truelight@2381: 			int dir1 = AiNew_GetRailDirection(parent->path.parent->node.tile, parent->path.node.tile, current->tile);
truelight@2381: 			int dir2 = AiNew_GetRailDirection(parent->path.parent->parent->node.tile, parent->path.parent->node.tile, parent->path.node.tile);
truelight@2381: 			// First, see if we are on diagonal path, that is better than straight path
tron@3033: 			if (dir1 > 1) res -= AI_PATHFINDER_DIAGONAL_BONUS;
truelight@2381: 
truelight@2381: 			// First see if they are different
truelight@2381: 			if (dir1 != dir2) {
truelight@2381: 				// dir 2 and 3 are 1 diagonal track, and 4 and 5.
truelight@2381: 				if (!(((dir1 == 2 || dir1 == 3) && (dir2 == 2 || dir2 == 3)) || ((dir1 == 4 || dir1 == 5) && (dir2 == 4 || dir2 == 5)))) {
truelight@2381: 					// It is not, so we changed of direction
truelight@2381: 					res += AI_PATHFINDER_DIRECTION_CHANGE_PENALTY;
truelight@2381: 				}
truelight@2381: 				if (parent->path.parent->parent->parent != NULL) {
truelight@2381: 					int dir3 = AiNew_GetRailDirection(parent->path.parent->parent->parent->node.tile, parent->path.parent->parent->node.tile, parent->path.parent->node.tile);
truelight@2381: 					// Check if we changed 3 tiles of direction in 3 tiles.. bad!!!
truelight@2381: 					if ((dir1 == 0 || dir1 == 1) && dir2 > 1 && (dir3 == 0 || dir3 == 1)) {
truelight@2381: 						res += AI_PATHFINDER_CURVE_PENALTY;
truelight@2381: 					}
truelight@2381: 				}
truelight@2381: 			}
truelight@2381: 		}
truelight@2381: 	}
truelight@2381: 
tron@2549: 	return (res < 0) ? 0 : res;
truelight@2381: }