diff options
Diffstat (limited to 'src/town_cmd.cpp')
| -rw-r--r-- | src/town_cmd.cpp | 35 |
1 files changed, 19 insertions, 16 deletions
diff --git a/src/town_cmd.cpp b/src/town_cmd.cpp index f243228f7..e04fccadb 100644 --- a/src/town_cmd.cpp +++ b/src/town_cmd.cpp @@ -895,26 +895,26 @@ static bool GrowTownWithRoad(const Town *t, TileIndex tile, RoadBits rcmd) * * @param t The current town * @param tile The current tile - * @param rcmd The RoadBits which are possible on this tile + * @param bridge_dir The valid direction in which to grow a bridge * @return true if a bridge has been build else false */ -static bool GrowTownWithBridge(const Town *t, TileIndex tile, RoadBits rcmd) +static bool GrowTownWithBridge(const Town *t, TileIndex tile, DiagDirection bridge_dir) { - DiagDirection bridge_dir; // The direction of a bridge we maybe want to build + assert(bridge_dir < DIAGDIR_END); - /* Determine direction of slope, - * and build a road if not a special slope. */ - switch (GetTileSlope(tile, NULL)) { - case SLOPE_SW: bridge_dir = DIAGDIR_NE; break; - case SLOPE_SE: bridge_dir = DIAGDIR_NW; break; - case SLOPE_NW: bridge_dir = DIAGDIR_SE; break; - case SLOPE_NE: bridge_dir = DIAGDIR_SW; break; - - default: return false; - } + const Slope slope = GetTileSlope(tile, NULL); + if (slope == SLOPE_FLAT) return false; // no slope, no bridge - /* Check if the bridge will be compatible to the RoadBits */ - if (!(rcmd & DiagDirToRoadBits(ReverseDiagDir(bridge_dir)))) return false; + /* Make sure the direction is compatible with the slope. + * If any of the following bits match, the slope is forbidden for + * that diagdir. Total of 5 slopes per direction. + * 0 -> 0b1100 + * 1 -> 0b0110 + * 2 -> 0b0011 + * 3 -> 0b1001 + * 0xCC is 0b11001100, so we just shift it right with + * the direction to get the forbidden slope mask. */ + if (HASBITS(slope & 0x0F, 0xCC >> bridge_dir)) return false; /* We are in the right direction */ uint32 bridge_length = 0; // This value stores the length of the possible bridge @@ -1120,7 +1120,10 @@ static void GrowTownInTile(TileIndex *tile_ptr, RoadBits cur_rb, DiagDirection t rcmd = CleanUpRoadBits(tile, rcmd); if (rcmd == ROAD_NONE) return; - if (GrowTownWithBridge(t1, tile, rcmd)) return; + /* Only use the target direction for bridges to ensure they're connected. + * The target_dir is as computed previously according to town layout, so + * it will match it perfectly. */ + if (GrowTownWithBridge(t1, tile, target_dir)) return; GrowTownWithRoad(t1, tile, rcmd); } |