diff options
| -rw-r--r-- | npf.c | 81 |
1 files changed, 73 insertions, 8 deletions
@@ -108,16 +108,82 @@ int32 NPFCalcZero(AyStar* as, AyStarNode* current, OpenListNode* parent) { return 0; } -/* Calcs the heuristic to the target station (using NPFFindStationOrTileData). After - * will save the heuristic into NPFFoundTargetData if it is the smallest until - * now. It will then also save AyStarNode.user_data[NPF_TRACKDIR_CHOICE] in - * best_trackdir +/* Calcs the tile of given station that is closest to a given tile + * for this we assume the station is a rectangle, + * as defined by its top tile (st->train_tile) and its width/height (st->trainst_w, st->trainst_h) + */ +TileIndex CalcClosestStationTile(int station, TileIndex tile) { + const Station* st = GetStation(station); + + int x1,x2,x3,tx; + int y1,y2,y3,ty; + + x1 = TileX(st->train_tile); y1 = TileY(st->train_tile); // topmost corner of station + x2 = x1 + st->trainst_w - 1; y2 = y1 + st->trainst_h - 1; // lowermost corner of station + x3 = TileX(tile); y3 = TileY(tile); // tile we take the distance from + + // we are going the aim for the x coordinate of the closest corner + // but if we are between those coordinates, we will aim for our own x coordinate + if (x3 < x1) + tx = x1; + else if (x3 > x2) + tx = x2; + else + tx = x3; + + // same for y coordinate, see above comment + if (y3 < y1) + ty = y1; + else if (y3 > y2) + ty = y2; + else + ty = y3; + + // return the tile of our target coordinates + return TILE_XY(tx,ty); +}; + +/* Calcs the heuristic to the target tile (using NPFFindStationOrTileData). + * If the target is a station, the heuristic is probably "wrong"! Normally + * this shouldn't matter, but if it turns out to be a problem, we could use + * the heuristic below? + * Afterthis will save the heuristic into NPFFoundTargetData if it is the + * smallest until now. It will then also save + * AyStarNode.user_data[NPF_TRACKDIR_CHOICE] in best_trackdir + */ +int32 NPFCalcTileHeuristic(AyStar* as, AyStarNode* current, OpenListNode* parent) { + NPFFindStationOrTileData* fstd = (NPFFindStationOrTileData*)as->user_target; + NPFFoundTargetData* ftd = (NPFFoundTargetData*)as->user_path; + TileIndex from = current->tile; + TileIndex to = fstd->dest_coords; + uint dist = DistanceManhattan(from, to) * NPF_TILE_LENGTH; + + if (dist < ftd->best_bird_dist) { + ftd->best_bird_dist = dist; + ftd->best_trackdir = current->user_data[NPF_TRACKDIR_CHOICE]; + } + #ifdef NPF_DEBUG + debug("Calculating H for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), dist); + #endif + return dist; +} + +/* Calcs the heuristic to the target station or tile. Almost the same as above + * function, but calculates the distance to train stations with + * CalcClosestStationTile instead. So is somewhat more correct for stations + * (truly optimistic), but this added correctness is not really required we + * believe (matthijs & Hackykid) */ int32 NPFCalcStationOrTileHeuristic(AyStar* as, AyStarNode* current, OpenListNode* parent) { NPFFindStationOrTileData* fstd = (NPFFindStationOrTileData*)as->user_target; NPFFoundTargetData* ftd = (NPFFoundTargetData*)as->user_path; TileIndex from = current->tile; TileIndex to = fstd->dest_coords; + + // for train-stations, we are going to aim for the closest station tile + if ((as->user_data[NPF_TYPE] == TRANSPORT_RAIL) && (fstd->station_index != -1)) + to = CalcClosestStationTile(fstd->station_index, from); + uint dist = DistanceManhattan(from, to) * NPF_TILE_LENGTH; if (dist < ftd->best_bird_dist) { @@ -130,6 +196,7 @@ int32 NPFCalcStationOrTileHeuristic(AyStar* as, AyStarNode* current, OpenListNod return dist; } + /* Fills AyStarNode.user_data[NPF_TRACKDIRCHOICE] with the chosen direction to * get here, either getting it from the current choice or from the parent's * choice */ @@ -747,11 +814,9 @@ void NPFFillWithOrderData(NPFFindStationOrTileData* fstd, Vehicle* v) { * So only for train orders to stations we fill fstd->station_index, for all * others only dest_coords */ if ((v->current_order.type) == OT_GOTO_STATION && v->type == VEH_Train) { - const Station* st = GetStation(v->current_order.station); - TileIndexDiffC center = {st->trainst_w/2, st->trainst_h/2}; fstd->station_index = v->current_order.station; - /* Let's take the center of the station as our target tile for trains */ - fstd->dest_coords = TILE_ADD(st->train_tile, ToTileIndexDiff(center)); + /* Let's take the closest tile of the station as our target for trains */ + fstd->dest_coords = CalcClosestStationTile(v->current_order.station, v->tile); } else { fstd->dest_coords = v->dest_tile; fstd->station_index = -1; |