diff options
| -rw-r--r-- | tunnelbridge_cmd.c | 72 |
1 files changed, 32 insertions, 40 deletions
diff --git a/tunnelbridge_cmd.c b/tunnelbridge_cmd.c index bddc02d2d..f4aeeaeeb 100644 --- a/tunnelbridge_cmd.c +++ b/tunnelbridge_cmd.c @@ -103,51 +103,44 @@ static inline const PalSpriteID *GetBridgeSpriteTable(int index, byte table) static inline byte GetBridgeFlags(int index) { return _bridge[index].flags;} -/** check if bridge can be built on slope - * direction 0 = X-axis, direction 1 = Y-axis - * is_start_tile = false <-- end tile - * is_start_tile = true <-- start tile + +/** Check the slope at the bridge ramps in three easy steps: + * - valid slopes without foundation + * - valid slopes with foundation + * - rest is invalid */ -static uint32 CheckBridgeSlope(Axis direction, Slope tileh, bool is_start_tile) +#define M(x) (1 << (x)) +static int32 CheckBridgeSlopeNorth(Axis axis, Slope tileh) { - if (IsSteepSlope(tileh)) return CMD_ERROR; + uint32 valid; - if (is_start_tile) { - /* check slope at start tile - - no extra cost - */ -#define M(x) (1 << (x)) - if (HASBIT(M(SLOPE_FLAT) | (direction == AXIS_X ? M(SLOPE_NE) : M(SLOPE_NW)), tileh)) return 0; + valid = M(SLOPE_FLAT) | (axis == AXIS_X ? M(SLOPE_NE) : M(SLOPE_NW)); + if (HASBIT(valid, tileh)) return 0; - // disallow certain start tiles to avoid certain crooked bridges - if (tileh == SLOPE_S) return CMD_ERROR; - } else { - /* check slope at end tile - - no extra cost - */ - if (HASBIT(M(SLOPE_FLAT) | (direction == AXIS_X ? M(SLOPE_SW) : M(SLOPE_SE)), tileh)) return 0; -#undef M + valid = + BRIDGE_FULL_LEVELED_FOUNDATION | M(SLOPE_N) | + (axis == AXIS_X ? M(SLOPE_E) : M(SLOPE_W)); + if (HASBIT(valid, tileh)) return _price.terraform; - // disallow certain end tiles to avoid certain crooked bridges - if (tileh == SLOPE_N) return CMD_ERROR; - } + return CMD_ERROR; +} - /* disallow common start/end tiles to avoid certain crooked bridges e.g. - * start-tile: X 2,1 Y 2,4 (2 was disabled before) - * end-tile: X 8,4 Y 8,1 (8 was disabled before) - */ - if ((tileh == SLOPE_W && is_start_tile != (direction != AXIS_X)) || - (tileh == SLOPE_E && is_start_tile == (direction != AXIS_X))) { - return CMD_ERROR; - } +static int32 CheckBridgeSlopeSouth(Axis axis, Slope tileh) +{ + uint32 valid; - // slope foundations - if (HASBIT(BRIDGE_FULL_LEVELED_FOUNDATION | BRIDGE_PARTLY_LEVELED_FOUNDATION, tileh)) { - return _price.terraform; - } + valid = M(SLOPE_FLAT) | (axis == AXIS_X ? M(SLOPE_SW) : M(SLOPE_SE)); + if (HASBIT(valid, tileh)) return 0; + + valid = + BRIDGE_FULL_LEVELED_FOUNDATION | M(SLOPE_S) | + (axis == AXIS_X ? M(SLOPE_W) : M(SLOPE_E)); + if (HASBIT(valid, tileh)) return _price.terraform; return CMD_ERROR; } +#undef M + uint32 GetBridgeLength(TileIndex begin, TileIndex end) { @@ -274,9 +267,8 @@ int32 CmdBuildBridge(TileIndex end_tile, uint32 flags, uint32 p1, uint32 p2) if (CmdFailed(ret)) return ret; cost = ret; - // true - bridge-start-tile, false - bridge-end-tile - terraformcost = CheckBridgeSlope(direction, tileh_start, true); - if (CmdFailed(terraformcost) || (terraformcost && !allow_on_slopes)) + terraformcost = CheckBridgeSlopeNorth(direction, tileh_start); + if (CmdFailed(terraformcost) || (terraformcost != 0 && !allow_on_slopes)) return_cmd_error(STR_1000_LAND_SLOPED_IN_WRONG_DIRECTION); cost += terraformcost; @@ -287,8 +279,8 @@ int32 CmdBuildBridge(TileIndex end_tile, uint32 flags, uint32 p1, uint32 p2) cost += ret; // false - end tile slope check - terraformcost = CheckBridgeSlope(direction, tileh_end, false); - if (CmdFailed(terraformcost) || (terraformcost && !allow_on_slopes)) + terraformcost = CheckBridgeSlopeSouth(direction, tileh_end); + if (CmdFailed(terraformcost) || (terraformcost != 0 && !allow_on_slopes)) return_cmd_error(STR_1000_LAND_SLOPED_IN_WRONG_DIRECTION); cost += terraformcost; |