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/* $Id$ */

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/** @file rail.h */

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#ifndef RAIL_H

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#define RAIL_H

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#include "gfx.h"

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#include "direction.h"

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#include "tile.h"

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#include "variables.h"

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    13

/**

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 * Enumeration for all possible railtypes.

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 *

    16

 * This enumeration defines all 4 possible railtypes.

    17

 */

    18

enum RailType {

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	RAILTYPE_BEGIN    = 0,          ///< Used for iterations

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	RAILTYPE_RAIL     = 0,          ///< Standard non-electric rails

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	RAILTYPE_ELECTRIC = 1,          ///< Electric rails

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	RAILTYPE_MONO     = 2,          ///< Monorail

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	RAILTYPE_MAGLEV   = 3,          ///< Maglev

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	RAILTYPE_END,                   ///< Used for iterations

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	INVALID_RAILTYPE  = 0xFF        ///< Flag for invalid railtype

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};

    27

    28

typedef byte RailTypeMask;

    29

    30

/** Allow incrementing of Track variables */

    31

DECLARE_POSTFIX_INCREMENT(RailType);

    32

/** Define basic enum properties */

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template <> struct EnumPropsT<RailType> : MakeEnumPropsT<RailType, byte, RAILTYPE_BEGIN, RAILTYPE_END, INVALID_RAILTYPE> {};

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typedef TinyEnumT<RailType> RailTypeByte;

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    36

    37

/**

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 * These are used to specify a single track.

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 * Can be translated to a trackbit with TrackToTrackbit

    40

 */

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enum Track {

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	TRACK_BEGIN = 0,        ///< Used for iterations

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	TRACK_X     = 0,        ///< Track along the x-axis (north-east to south-west)

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	TRACK_Y     = 1,        ///< Track along the y-axis (north-west to south-east)

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	TRACK_UPPER = 2,        ///< Track in the upper corner of the tile (north)

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	TRACK_LOWER = 3,        ///< Track in the lower corner of the tile (south)

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	TRACK_LEFT  = 4,        ///< Track in the left corner of the tile (west)

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	TRACK_RIGHT = 5,        ///< Track in the right corner of the tile (east)

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	TRACK_END,              ///< Used for iterations

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	INVALID_TRACK = 0xFF    ///< Flag for an invalid track

    51

};

    52

    53

/** Allow incrementing of Track variables */

    54

DECLARE_POSTFIX_INCREMENT(Track);

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/** Define basic enum properties */

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template <> struct EnumPropsT<Track> : MakeEnumPropsT<Track, byte, TRACK_BEGIN, TRACK_END, INVALID_TRACK> {};

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typedef TinyEnumT<Track> TrackByte;

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    59

    60

/**

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 * Convert an Axis to the corresponding Track

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 * AXIS_X -> TRACK_X

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 * AXIS_Y -> TRACK_Y

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 * Uses the fact that they share the same internal encoding

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 *

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 * @param a the axis to convert

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 * @return the track corresponding to the axis

    68

 */

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static inline Track AxisToTrack(Axis a)

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{

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	return (Track)a;

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}

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    74

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/** Bitfield corresponding to Track */

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enum TrackBits {

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	TRACK_BIT_NONE    = 0U,                                                 ///< No track

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	TRACK_BIT_X       = 1U << TRACK_X,                                      ///< X-axis track

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	TRACK_BIT_Y       = 1U << TRACK_Y,                                      ///< Y-axis track

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	TRACK_BIT_UPPER   = 1U << TRACK_UPPER,                                  ///< Upper track

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	TRACK_BIT_LOWER   = 1U << TRACK_LOWER,                                  ///< Lower track

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	TRACK_BIT_LEFT    = 1U << TRACK_LEFT,                                   ///< Left track

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	TRACK_BIT_RIGHT   = 1U << TRACK_RIGHT,                                  ///< Right track

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	TRACK_BIT_CROSS   = TRACK_BIT_X     | TRACK_BIT_Y,                      ///< X-Y-axis cross

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	TRACK_BIT_HORZ    = TRACK_BIT_UPPER | TRACK_BIT_LOWER,                  ///< Upper and lower track

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	TRACK_BIT_VERT    = TRACK_BIT_LEFT  | TRACK_BIT_RIGHT,                  ///< Left and right track

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	TRACK_BIT_3WAY_NE = TRACK_BIT_X     | TRACK_BIT_UPPER | TRACK_BIT_RIGHT,///< "Arrow" to the north-east

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	TRACK_BIT_3WAY_SE = TRACK_BIT_Y     | TRACK_BIT_LOWER | TRACK_BIT_RIGHT,///< "Arrow" to the south-east

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	TRACK_BIT_3WAY_SW = TRACK_BIT_X     | TRACK_BIT_LOWER | TRACK_BIT_LEFT, ///< "Arrow" to the south-west

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	TRACK_BIT_3WAY_NW = TRACK_BIT_Y     | TRACK_BIT_UPPER | TRACK_BIT_LEFT, ///< "Arrow" to the north-west

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	TRACK_BIT_ALL     = TRACK_BIT_CROSS | TRACK_BIT_HORZ  | TRACK_BIT_VERT, ///< All possible tracks

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	TRACK_BIT_MASK    = 0x3FU,                                              ///< Bitmask for the first 6 bits

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	TRACK_BIT_WORMHOLE = 0x40U,                                             ///< Bitflag for a wormhole (used for tunnels)

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	TRACK_BIT_DEPOT   = 0x80U,                                              ///< Bitflag for a depot

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	INVALID_TRACK_BIT = 0xFF                                                ///< Flag for an invalid trackbits value

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};

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    98

/** Define basic enum properties */

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template <> struct EnumPropsT<TrackBits> : MakeEnumPropsT<TrackBits, byte, TRACK_BIT_NONE, TRACK_BIT_ALL, INVALID_TRACK_BIT> {};

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typedef TinyEnumT<TrackBits> TrackBitsByte;

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   102

DECLARE_ENUM_AS_BIT_SET(TrackBits);

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   104

/**

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 * Maps a Track to the corresponding TrackBits value

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 * @param track the track to convert

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 * @return the converted TrackBits value of the track

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 */

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static inline TrackBits TrackToTrackBits(Track track)

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{

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	return (TrackBits)(1 << track);

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}

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/**

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 * Maps an Axis to the corresponding TrackBits value

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 * @param a the axis to convert

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 * @return the converted TrackBits value of the axis

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 */

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static inline TrackBits AxisToTrackBits(Axis a)

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{

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	return TrackToTrackBits(AxisToTrack(a));

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}

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/**

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 * Returns a single horizontal/vertical trackbit, that is in a specific tile corner.

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 *

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 * @param corner The corner of a tile.

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 * @return The TrackBits of the track in the corner.

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 */

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static inline TrackBits CornerToTrackBits(Corner corner)

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{

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	extern const TrackBits _corner_to_trackbits[];

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	assert(IsValidCorner(corner));

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	return _corner_to_trackbits[corner];

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}

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   137

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/**

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 * Enumeration for tracks and directions.

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 *

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 * These are a combination of tracks and directions. Values are 0-5 in one

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 * direction (corresponding to the Track enum) and 8-13 in the other direction.

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 * 6, 7, 14 and 15 are used to encode the reversing of road vehicles. Those

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 * reversing track dirs are not considered to be 'valid' except in a small

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 * corner in the road vehicle controller.

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 */

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enum Trackdir {

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	TRACKDIR_BEGIN    =  0,         ///< Used for iterations

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	TRACKDIR_X_NE     =  0,         ///< X-axis and direction to north-east

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	TRACKDIR_Y_SE     =  1,         ///< Y-axis and direction to south-east

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	TRACKDIR_UPPER_E  =  2,         ///< Upper track and direction to east

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	TRACKDIR_LOWER_E  =  3,         ///< Lower track and direction to east

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	TRACKDIR_LEFT_S   =  4,         ///< Left track and direction to south

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	TRACKDIR_RIGHT_S  =  5,         ///< Right track and direction to south

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	TRACKDIR_RVREV_NE =  6,         ///< (Road vehicle) reverse direction north-east

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	TRACKDIR_RVREV_SE =  7,         ///< (Road vehicle) reverse direction south-east

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	TRACKDIR_X_SW     =  8,         ///< X-axis and direction to south-west

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	TRACKDIR_Y_NW     =  9,         ///< Y-axis and direction to north-west

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	TRACKDIR_UPPER_W  = 10,         ///< Upper track and direction to west

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	TRACKDIR_LOWER_W  = 11,         ///< Lower track and direction to west

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	TRACKDIR_LEFT_N   = 12,         ///< Left track and direction to north

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	TRACKDIR_RIGHT_N  = 13,         ///< Right track and direction to north

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	TRACKDIR_RVREV_SW = 14,         ///< (Road vehicle) reverse direction south-west

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	TRACKDIR_RVREV_NW = 15,         ///< (Road vehicle) reverse direction north-west

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	TRACKDIR_END,                   ///< Used for iterations

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	INVALID_TRACKDIR  = 0xFF,       ///< Flag for an invalid trackdir

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};

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/** Define basic enum properties */

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template <> struct EnumPropsT<Trackdir> : MakeEnumPropsT<Trackdir, byte, TRACKDIR_BEGIN, TRACKDIR_END, INVALID_TRACKDIR> {};

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typedef TinyEnumT<Trackdir> TrackdirByte;

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   173

/**

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 * Enumeration of bitmasks for the TrackDirs

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 *

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 * These are a combination of tracks and directions. Values are 0-5 in one

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 * direction (corresponding to the Track enum) and 8-13 in the other direction.

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 */

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enum TrackdirBits {

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	TRACKDIR_BIT_NONE     = 0x0000, ///< No track build

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	TRACKDIR_BIT_X_NE     = 0x0001, ///< Track x-axis, direction north-east

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	TRACKDIR_BIT_Y_SE     = 0x0002, ///< Track y-axis, direction south-east

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	TRACKDIR_BIT_UPPER_E  = 0x0004, ///< Track upper, direction east

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	TRACKDIR_BIT_LOWER_E  = 0x0008, ///< Track lower, direction east

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	TRACKDIR_BIT_LEFT_S   = 0x0010, ///< Track left, direction south

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	TRACKDIR_BIT_RIGHT_S  = 0x0020, ///< Track right, direction south

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	/* Again, note the two missing values here. This enables trackdir -> track conversion by doing (trackdir & 0xFF) */

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	TRACKDIR_BIT_X_SW     = 0x0100, ///< Track x-axis, direction south-west

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	TRACKDIR_BIT_Y_NW     = 0x0200, ///< Track y-axis, direction north-west

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	TRACKDIR_BIT_UPPER_W  = 0x0400, ///< Track upper, direction west

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	TRACKDIR_BIT_LOWER_W  = 0x0800, ///< Track lower, direction west

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	TRACKDIR_BIT_LEFT_N   = 0x1000, ///< Track left, direction north

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	TRACKDIR_BIT_RIGHT_N  = 0x2000, ///< Track right, direction north

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	TRACKDIR_BIT_MASK     = 0x3F3F, ///< Bitmask for bit-operations

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	INVALID_TRACKDIR_BIT  = 0xFFFF, ///< Flag for an invalid trackdirbit value

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};

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/** Define basic enum properties */

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template <> struct EnumPropsT<TrackdirBits> : MakeEnumPropsT<TrackdirBits, uint16, TRACKDIR_BIT_NONE, TRACKDIR_BIT_MASK, INVALID_TRACKDIR_BIT> {};

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typedef TinyEnumT<TrackdirBits> TrackdirBitsShort;

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DECLARE_ENUM_AS_BIT_SET(TrackdirBits);

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/** This struct contains all the info that is needed to draw and construct tracks.

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 */

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struct RailtypeInfo {

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	/** Struct containing the main sprites. @note not all sprites are listed, but only

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	 *  the ones used directly in the code */

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	struct {

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		SpriteID track_y;      ///< single piece of rail in Y direction, with ground

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		SpriteID track_ns;     ///< two pieces of rail in North and South corner (East-West direction)

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		SpriteID ground;       ///< ground sprite for a 3-way switch

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		SpriteID single_y;     ///< single piece of rail in Y direction, without ground

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		SpriteID single_x;     ///< single piece of rail in X direction

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		SpriteID single_n;     ///< single piece of rail in the northern corner

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		SpriteID single_s;     ///< single piece of rail in the southern corner

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		SpriteID single_e;     ///< single piece of rail in the eastern corner

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		SpriteID single_w;     ///< single piece of rail in the western corner

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		SpriteID crossing;     ///< level crossing, rail in X direction

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		SpriteID tunnel;       ///< tunnel sprites base

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	} base_sprites;

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	/** struct containing the sprites for the rail GUI. @note only sprites referred to

   223

	 * directly in the code are listed */

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	struct {

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		SpriteID build_ns_rail;      ///< button for building single rail in N-S direction

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		SpriteID build_x_rail;       ///< button for building single rail in X direction

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		SpriteID build_ew_rail;      ///< button for building single rail in E-W direction

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		SpriteID build_y_rail;       ///< button for building single rail in Y direction

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		SpriteID auto_rail;          ///< button for the autorail construction

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		SpriteID build_depot;        ///< button for building depots

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		SpriteID build_tunnel;       ///< button for building a tunnel

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		SpriteID convert_rail;       ///< button for converting rail

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	} gui_sprites;

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	struct {

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		CursorID rail_ns;    ///< Cursor for building rail in N-S direction

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		CursorID rail_swne;  ///< Cursor for building rail in X direction

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		CursorID rail_ew;    ///< Cursor for building rail in E-W direction

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		CursorID rail_nwse;  ///< Cursor for building rail in Y direction

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		CursorID autorail;   ///< Cursor for autorail tool

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		CursorID depot;      ///< Cursor for building a depot

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		CursorID tunnel;     ///< Cursor for building a tunnel

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		CursorID convert;    ///< Cursor for converting track

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	} cursor;

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	struct {

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		StringID toolbar_caption;

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	} strings;

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	/** sprite number difference between a piece of track on a snowy ground and the corresponding one on normal ground */

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	SpriteID snow_offset;

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   253

	/** bitmask to the OTHER railtypes on which an engine of THIS railtype generates power */

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	RailTypeMask powered_railtypes;

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   256

	/** bitmask to the OTHER railtypes on which an engine of THIS railtype can physically travel */

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	RailTypeMask compatible_railtypes;

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	/**

   260

	 * Offset between the current railtype and normal rail. This means that:<p>

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	 * 1) All the sprites in a railset MUST be in the same order. This order

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	 *    is determined by normal rail. Check sprites 1005 and following for this order<p>

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	 * 2) The position where the railtype is loaded must always be the same, otherwise

   264

	 *    the offset will fail.

   265

	 * @note: Something more flexible might be desirable in the future.

   266

	 */

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	SpriteID total_offset;

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   269

	/**

   270

	 * Bridge offset

   271

	 */

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	SpriteID bridge_offset;

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   274

	/**

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	 * Offset to add to ground sprite when drawing custom waypoints / stations

   276

	 */

   277

	byte custom_ground_offset;

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};

   279

   280

   281

/** these are the maximums used for updating signal blocks, and checking if a depot is in a pbs block */

   282

enum {

   283

	NUM_SSD_ENTRY = 256, ///< max amount of blocks

   284

	NUM_SSD_STACK =  32, ///< max amount of blocks to check recursively

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};

   286

   287

/**

   288

 * Maps a Trackdir to the corresponding TrackdirBits value

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 * @param trackdir the track direction to convert

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 * @return the converted TrackdirBits value

   291

 */

   292

static inline TrackdirBits TrackdirToTrackdirBits(Trackdir trackdir)

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{

   294

	return (TrackdirBits)(1 << trackdir);

   295

}

   296

   297

/**

   298

 * Removes first Track from TrackBits and returns it

   299

 *

   300

 * This function searchs for the first bit in the TrackBits,

   301

 * remove this bit from the parameter and returns the found

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 * bit as Track value. It returns INVALID_TRACK if the

   303

 * parameter was TRACK_BIT_NONE or INVALID_TRACK_BIT. This

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 * is basically used in while-loops to get up to 6 possible

   305

 * tracks on a tile until the parameter becomes TRACK_BIT_NONE.

   306

 *

   307

 * @param tracks The value with the TrackBits

   308

 * @return The first Track from the TrackBits value

   309

 * @see FindFirstTrack

   310

 */

   311

static inline Track RemoveFirstTrack(TrackBits *tracks)

   312

{

   313

	if (*tracks != TRACK_BIT_NONE && *tracks != INVALID_TRACK_BIT) {

   314

		Track first = (Track)FIND_FIRST_BIT(*tracks);

   315

		ClrBit(*tracks, first);

   316

		return first;

   317

	}

   318

	return INVALID_TRACK;

   319

}

   320

   321

/**

   322

 * Removes first Trackdir from TrackdirBits and returns it

   323

 *

   324

 * This function searchs for the first bit in the TrackdirBits parameter,

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 * remove this bit from the parameter and returns the fnound bit as

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 * Trackdir value. It returns INVALID_TRACKDIR if the trackdirs is

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 * TRACKDIR_BIT_NONE or INVALID_TRACKDIR_BIT. This is basically used in a

   328

 * while-loop to get all track-directions step by step until the value

   329

 * reaches TRACKDIR_BIT_NONE.

   330

 *

   331

 * @param trackdirs The value with the TrackdirBits

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 * @return The first Trackdir from the TrackdirBits value

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 * @see FindFirstTrackdir

   334

 */

   335

static inline Trackdir RemoveFirstTrackdir(TrackdirBits *trackdirs)

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{

   337

	if (*trackdirs != TRACKDIR_BIT_NONE && *trackdirs != INVALID_TRACKDIR_BIT) {

   338

		Trackdir first = (Trackdir)FindFirstBit2x64(*trackdirs);

   339

		ClrBit(*trackdirs, first);

   340

		return first;

   341

	}

   342

	return INVALID_TRACKDIR;

   343

}

   344

   345

/**

   346

 * Returns first Track from TrackBits or INVALID_TRACK

   347

 *

   348

 * This function returns the first Track found in the TrackBits value as Track-value.

   349

 * It returns INVALID_TRACK if the parameter is TRACK_BIT_NONE or INVALID_TRACK_BIT.

   350

 *

   351

 * @param tracks The TrackBits value

   352

 * @return The first Track found or INVALID_TRACK

   353

 * @see RemoveFirstTrack

   354

 */

   355

static inline Track FindFirstTrack(TrackBits tracks)

   356

{

   357

	return (tracks != TRACK_BIT_NONE && tracks != INVALID_TRACK_BIT) ? (Track)FIND_FIRST_BIT(tracks) : INVALID_TRACK;

   358

}

   359

   360

/**

   361

 * Converts TrackBits to Track.

   362

 *

   363

 * This function converts a TrackBits value to a Track value. As it

   364

 * is not possible to convert two or more tracks to one track the

   365

 * parameter must contain only one track or be the INVALID_TRACK_BIT value.

   366

 *

   367

 * @param tracks The TrackBits value to convert

   368

 * @return The Track from the value or INVALID_TRACK

   369

 * @pre tracks must contains only one Track or be INVALID_TRACK_BIT

   370

 */

   371

static inline Track TrackBitsToTrack(TrackBits tracks)

   372

{

   373

	assert(tracks == INVALID_TRACK_BIT || (tracks != TRACK_BIT_NONE && KillFirstBit(tracks & TRACK_BIT_MASK) == TRACK_BIT_NONE));

   374

	return tracks != INVALID_TRACK_BIT ? (Track)FIND_FIRST_BIT(tracks & TRACK_BIT_MASK) : INVALID_TRACK;

   375

}

   376

   377

/**

   378

 * Returns first Trackdir from TrackdirBits or INVALID_TRACKDIR

   379

 *

   380

 * This function returns the first Trackdir in the given TrackdirBits value or

   381

 * INVALID_TRACKDIR if the value is TRACKDIR_BIT_NONE. The TrackdirBits must

   382

 * not be INVALID_TRACKDIR_BIT.

   383

 *

   384

 * @param trackdirs The TrackdirBits value

   385

 * @return The first Trackdir from the TrackdirBits or INVALID_TRACKDIR on TRACKDIR_BIT_NONE.

   386

 * @pre trackdirs must not be INVALID_TRACKDIR_BIT

   387

 * @see RemoveFirstTrackdir

   388

 */

   389

static inline Trackdir FindFirstTrackdir(TrackdirBits trackdirs)

   390

{

   391

	assert((trackdirs & ~TRACKDIR_BIT_MASK) == TRACKDIR_BIT_NONE);

   392

	return (trackdirs != TRACKDIR_BIT_NONE) ? (Trackdir)FindFirstBit2x64(trackdirs) : INVALID_TRACKDIR;

   393

}

   394

   395

/**

   396

 * Checks if a Track is valid.

   397

 *

   398

 * @param track The value to check

   399

 * @return true if the given value is a valid track.

   400

 * @note Use this in an assert()

   401

 */

   402

static inline bool IsValidTrack(Track track)

   403

{

   404

	return track < TRACK_END;

   405

}

   406

   407

/**

   408

 * Checks if a Trackdir is valid.

   409

 *

   410

 * @param trackdir The value to check

   411

 * @return true if the given valie is a valid Trackdir

   412

 * @note Use this in an assert()

   413

 */

   414

static inline bool IsValidTrackdir(Trackdir trackdir)

   415

{

   416

	return (TrackdirToTrackdirBits(trackdir) & TRACKDIR_BIT_MASK) != 0;

   417

}

   418

   419

/*

   420

 * Functions to map tracks to the corresponding bits in the signal

   421

 * presence/status bytes in the map. You should not use these directly, but

   422

 * wrapper functions below instead. XXX: Which are these?

   423

 */

   424

   425

/**

   426

 * Maps a trackdir to the bit that stores its status in the map arrays, in the

   427

 * direction along with the trackdir.

   428

 */

   429

static inline byte SignalAlongTrackdir(Trackdir trackdir)

   430

{

   431

	extern const byte _signal_along_trackdir[TRACKDIR_END];

   432

	return _signal_along_trackdir[trackdir];

   433

}

   434

   435

/**

   436

 * Maps a trackdir to the bit that stores its status in the map arrays, in the

   437

 * direction against the trackdir.

   438

 */

   439

static inline byte SignalAgainstTrackdir(Trackdir trackdir)

   440

{

   441

	extern const byte _signal_against_trackdir[TRACKDIR_END];

   442

	return _signal_against_trackdir[trackdir];

   443

}

   444

   445

/**

   446

 * Maps a Track to the bits that store the status of the two signals that can

   447

 * be present on the given track.

   448

 */

   449

static inline byte SignalOnTrack(Track track)

   450

{

   451

	extern const byte _signal_on_track[TRACK_END];

   452

	return _signal_on_track[track];

   453

}

   454

   455

   456

/*

   457

 * Functions describing logical relations between Tracks, TrackBits, Trackdirs

   458

 * TrackdirBits, Direction and DiagDirections.

   459

 */

   460

   461

/**

   462

 * Maps a trackdir to the reverse trackdir.

   463

 *

   464

 * Returns the reverse trackdir of a Trackdir value. The reverse trackdir

   465

 * is the same track with the other direction on it.

   466

 *

   467

 * @param trackdir The Trackdir value

   468

 * @return The reverse trackdir

   469

 * @pre trackdir must not be INVALID_TRACKDIR

   470

 */

   471

static inline Trackdir ReverseTrackdir(Trackdir trackdir)

   472

{

   473

	assert(trackdir != INVALID_TRACKDIR);

   474

	return (Trackdir)(trackdir ^ 8);

   475

}

   476

   477

/**

   478

 * Returns the Track that a given Trackdir represents

   479

 *

   480

 * This function filters the Track which is used in the Trackdir value and

   481

 * returns it as a Track value.

   482

 *

   483

 * @param trackdir The trackdir value

   484

 * @return The Track which is used in the value

   485

 */

   486

static inline Track TrackdirToTrack(Trackdir trackdir)

   487

{

   488

	return (Track)(trackdir & 0x7);

   489

}

   490