src/bridge.h

   1 /* $Id$ */
   2
   3 /*
   4  * This file is part of OpenTTD.
   5  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
   6  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   7  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
   8  */
   9
  10 /** @file bridge.h Header file for bridges */
  11
  12 #ifndef BRIDGE_H
  13 #define BRIDGE_H
  14
  15 #include "gfx_type.h"
  16 #include "tile_cmd.h"
  17 #include "slope_func.h"
  18 #include "viewport_func.h"
  19
  20 /**
  21  * This enum is related to the definition of bridge pieces,
  22  * which is used to determine the proper sprite table to use
  23  * while drawing a given bridge part.
  24  */
  25 enum BridgePieces {
  26         BRIDGE_PIECE_NORTH = 0,
  27         BRIDGE_PIECE_SOUTH,
  28         BRIDGE_PIECE_INNER_NORTH,
  29         BRIDGE_PIECE_INNER_SOUTH,
  30         BRIDGE_PIECE_MIDDLE_ODD,
  31         BRIDGE_PIECE_MIDDLE_EVEN,
  32         BRIDGE_PIECE_HEAD,
  33         BRIDGE_PIECE_INVALID,
  34 };
  35
  36 DECLARE_POSTFIX_INCREMENT(BridgePieces)
  37
  38 static const uint MAX_BRIDGES = 13; ///< Maximal number of available bridge specs.
  39
  40 typedef uint BridgeType; ///< Bridge spec number.
  41
  42 /**
  43  * Struct containing information about a single bridge type
  44  */
  45 struct BridgeSpec {
  46         Year avail_year;             ///< the year where it becomes available
  47         byte min_length;             ///< the minimum length (not counting start and end tile)
  48         uint16 max_length;           ///< the maximum length (not counting start and end tile)
  49         uint16 price;                ///< the price multiplier
  50         uint16 speed;                ///< maximum travel speed (1 unit = 1/1.6 mph = 1 km-ish/h)
  51         SpriteID sprite;             ///< the sprite which is used in the GUI
  52         PaletteID pal;               ///< the palette which is used in the GUI
  53         StringID material;           ///< the string that contains the bridge description
  54         StringID transport_name[2];  ///< description of the bridge, when built for road or rail
  55         PalSpriteID **sprite_table;  ///< table of sprites for drawing the bridge
  56         byte flags;                  ///< bit 0 set: disable drawing of far pillars.
  57 };
  58
  59 extern BridgeSpec _bridge[MAX_BRIDGES];
  60
  61 Foundation GetBridgeFoundation(Slope tileh, Axis axis);
  62 bool HasBridgeFlatRamp(Slope tileh, Axis axis);
  63
  64 /**
  65  * Get the height increase for a bridge ramp
  66  * @param dir Bridge direction
  67  * @param x x within the tile
  68  * @param y y within the tile
  69  */
  70 static inline int GetBridgePartialPixelZ(DiagDirection dir, uint x, uint y)
  71 {
  72         assert(x < TILE_SIZE);
  73         assert(y < TILE_SIZE);
  74
  75         return DistanceFromTileEdge(ReverseDiagDir(dir), x, y) / 2 + 1;
  76 }
  77
  78 /**
  79  * Get the direction(s) to which rail/road can be connected in an extended bridgehead.
  80  * @param tileh Slope of the tile
  81  * @param dir Direction of the bridge
  82  * @return DIAGDIRDIFF_SAME for all directions allowed; DIAGDIRDIFF_REVERSE for none (invalid slope); else invalid direction as a difference from dir
  83  */
  84 static inline DiagDirDiff CheckExtendedBridgeHead(Slope tileh, DiagDirection dir)
  85 {
  86         extern const Slope bridgehead_valid_slopes[DIAGDIR_END][2];
  87
  88         if (tileh == InclinedSlope(ReverseDiagDir(dir))) {
  89                 return DIAGDIRDIFF_SAME;
  90         } else if (tileh == bridgehead_valid_slopes[dir][0]) {
  91                 return DIAGDIRDIFF_90RIGHT;
  92         } else if (tileh == bridgehead_valid_slopes[dir][1]) {
  93                 return DIAGDIRDIFF_90LEFT;
  94         } else {
  95                 return DIAGDIRDIFF_REVERSE;
  96         }
  97 }
  98
  99 /**
 100  * Get the specification of a bridge type.
 101  * @param i The type of bridge to get the specification for.
 102  * @return The specification.
 103  */
 104 static inline const BridgeSpec *GetBridgeSpec(BridgeType i)
 105 {
 106         assert(i < lengthof(_bridge));
 107         return &_bridge[i];
 108 }
 109
 110 int GetBridgeHeight(TileIndex tile);
 111 /**
 112  * Get the height ('z') of a bridge in pixels.
 113  * @param tile the bridge ramp tile to get the bridge height from
 114  * @return the height of the bridge in pixels
 115  */
 116 static inline int GetBridgePixelHeight(TileIndex tile)
 117 {
 118         return GetBridgeHeight(tile) * TILE_HEIGHT;
 119 }
 120
 121 void DrawBridgeTramBits(int x, int y, int z, int offset, bool overlay, bool head);
 122 void DrawBridgeMiddle(const TileInfo *ti);
 123 void DrawBridgeGround(TileInfo *ti);
 124 const PalSpriteID *GetBridgeRampSprite(int index, int offset, Slope slope, DiagDirection dir);
 125 void DrawAqueductRamp(TileInfo *ti);
 126
 127 CommandCost CheckBridgeAvailability(BridgeType bridge_type, uint bridge_len, DoCommandFlag flags = DC_NONE);
 128 int CalcBridgeLenCostFactor(int x);
 129
 130 void ResetBridges();
 131
 132 CommandCost CheckBridgeTiles(TileIndex tile1, TileIndex tile2, Axis *axis);
 133 CommandCost CheckBridgeBuildable(TileIndex tile1, TileIndex tile2, DoCommandFlag flags, bool clear1, bool clear2, bool restricted = false);
 134 CommandCost CheckBridgeSlope(DiagDirection dir, Slope *tileh, int *z);
 135
 136 static inline void MarkBridgeTilesDirty(TileIndex start, TileIndex end, DiagDirection dir, bool first = true)
 137 {
 138         assert(DiagdirBetweenTiles(start, end) == dir);
 139
 140         TileIndexDiff delta = TileOffsByDiagDir(dir);
 141         for (TileIndex tile = (first ? start : start + delta); tile != end; tile += delta) {
 142                 MarkTileDirtyByTile(tile);
 143         }
 144         MarkTileDirtyByTile(end);
 145 }
 146
 147 void SetBridgeMiddleTiles(TileIndex tile1, TileIndex tile2, Axis direction);
 148 void RemoveBridgeMiddleTiles(TileIndex tile1, TileIndex tile2);
 149
 150 #endif /* BRIDGE_H */