inline int CurveCost(Trackdir td1, Trackdir td2)
{
assert(IsValidTrackdir(td1));
assert(IsValidTrackdir(td2));
int cost = 0;
if (TrackFollower::Allow90degTurns()
&& ((TrackdirToTrackdirBits(td2) & (TrackdirBits)TrackdirCrossesTrackdirs(td1)) != 0)) {
/* 90-deg curve penalty */
cost += Yapf().PfGetSettings().rail_curve90_penalty;
} else if (td2 != NextTrackdir(td1)) {
/* 45-deg curve penalty */
cost += Yapf().PfGetSettings().rail_curve45_penalty;
}
return cost;
}
/**
* Calculates a hash value for use in the NPF.
* @param key1 The TileIndex of the tile to hash
* @param key2 The Trackdir of the track on the tile.
*
* @todo Think of a better hash.
*/
static uint NPFHash(uint key1, uint key2)
{
/* TODO: think of a better hash? */
uint part1 = TileX(key1) & NPF_HASH_HALFMASK;
uint part2 = TileY(key1) & NPF_HASH_HALFMASK;
assert(IsValidTrackdir((Trackdir)key2));
assert(IsValidTile(key1));
return ((part1 << NPF_HASH_HALFBITS | part2) + (NPF_HASH_SIZE * key2 / TRACKDIR_END)) % NPF_HASH_SIZE;
}
static Trackdir ChooseShipTrack(const Ship *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks, bool &path_found)
{
/* handle special case - when next tile is destination tile */
if (tile == v->dest_tile) {
/* convert tracks to trackdirs */
TrackdirBits trackdirs = (TrackdirBits)(tracks | ((int)tracks << 8));
/* limit to trackdirs reachable from enterdir */
trackdirs &= DiagdirReachesTrackdirs(enterdir);
/* use vehicle's current direction if that's possible, otherwise use first usable one. */
Trackdir veh_dir = v->GetVehicleTrackdir();
return ((trackdirs & TrackdirToTrackdirBits(veh_dir)) != 0) ? veh_dir : (Trackdir)FindFirstBit2x64(trackdirs);
}
/* move back to the old tile/trackdir (where ship is coming from) */
TileIndex src_tile = TILE_ADD(tile, TileOffsByDiagDir(ReverseDiagDir(enterdir)));
Trackdir trackdir = v->GetVehicleTrackdir();
assert(IsValidTrackdir(trackdir));
/* convert origin trackdir to TrackdirBits */
TrackdirBits trackdirs = TrackdirToTrackdirBits(trackdir);
/* get available trackdirs on the destination tile */
TrackdirBits dest_trackdirs = TrackStatusToTrackdirBits(GetTileTrackStatus(v->dest_tile, TRANSPORT_WATER, 0));
/* create pathfinder instance */
Tpf pf;
/* set origin and destination nodes */
pf.SetOrigin(src_tile, trackdirs);
pf.SetDestination(v->dest_tile, dest_trackdirs);
/* find best path */
path_found = pf.FindPath(v);
Trackdir next_trackdir = INVALID_TRACKDIR; // this would mean "path not found"
Node *pNode = pf.GetBestNode();
if (pNode != NULL) {
/* walk through the path back to the origin */
Node *pPrevNode = NULL;
while (pNode->m_parent != NULL) {
pPrevNode = pNode;
pNode = pNode->m_parent;
}
/* return trackdir from the best next node (direct child of origin) */
Node& best_next_node = *pPrevNode;
assert(best_next_node.GetTile() == tile);
next_trackdir = best_next_node.GetTrackdir();
}
return next_trackdir;
}
