tile.h

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program 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, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *
 * Based on the original sources
 *   Faery Tale II -- The Halls of the Dead
 *   (c) 1993-1996 The Wyrmkeep Entertainment Co.
 */

#ifndef SAGA2_TILE_H
#define SAGA2_TILE_H

#include "common/memstream.h"
#include "saga2/fta.h"
#include "saga2/tileload.h"
#include "saga2/annoy.h"
#include "saga2/terrain.h"
#include "saga2/property.h"
#include "saga2/tcoords.h"

namespace Saga2 {

/* ===================================================================== *
   Tile ID's and associated functions
 * ===================================================================== */

class   TileBank;
typedef TileBank    *TileBankPtr;           // pointer to tile bank


inline TileID makeTileID(int bank, int num) {
    return (TileID)((bank << 10) | num);
}

inline void TileID2Bank(TileID t, int16 &bank, int16 &num) {
    bank = (int16)(t >> 10);
    num = (int16)(t & 0x3ff);
}

/* ===================================================================== *
   Inline functions
 * ===================================================================== */

//  Given a U between 0 and 3, and a V between 0 and 3, compute
//  a terrain mask for the subtile at (U,V)

inline int16 calcSubTileMask(int u, int v) {
    return (int16)(1 << ((u << 2) + v));
}

/* ===================================================================== *
   Tile Attributes
 * ===================================================================== */

struct TileAttrs {


    //  Height above base of tile below which terrain has effect
    uint8           terrainHeight;

    //  Visual information
    uint8           height;                 // height of tile bitmap

    //  Terrain information

    uint16          terrainMask;            // 16 terrain selector bits
    uint8           fgdTerrain,
                    bgdTerrain;

    //  Reserved bytes
    uint8           reserved0[8];         // auto-terrain data

    //  Masking information

    uint8           maskRule,               // which tile masking rule to use
                    altMask;                // for tiles with special masks

    //  Altitude information

    uint8           cornerHeight[4];

    //  Animation information

    uint8           cycleRange;             // cycle range for tile
    uint8           tileFlags;              // various flags for tile

    //  Reserved bytes
    uint16          reserved1;

    int32 testTerrain(int16 mask) {
        int32       terrain = 0;

        if (terrainMask & mask)  terrain |= (1 << fgdTerrain);
        if (~terrainMask & mask) terrain |= (1 << bgdTerrain);
        return terrain;
    }
};

enum tile_flags {
    //  This tile has been used in at least one activity group
    kTileInGroup     = (1 << 0),

    //  Indicates that an activity group should be placed in lieu
    //  of the tile.
    kTileAutoGroup   = (1 << 1),

    //  Indicates that the tile is sensitive to being walked on
    kTileWalkSense   = (1 << 2),

    //  Indicates that tile has been recently modified
    kTileModified    = (1 << 3)
};

/* ===================================================================== *
   Terrain types
 * ===================================================================== */

enum terrainTypes {
    kTerrNumNormal   = 0,
    kTerrNumEasy,
    kTerrNumRough,
    kTerrNumStone,
    kTerrNumWood,
    kTerrNumHedge,
    kTerrNumTree,
    kTerrNumWater,
    kTerrNumFall,
    kTerrNumRamp,
    kTerrNumStair,
    kTerrNumLadder,
    kTerrNumObject,
    kTerrNumActive,
    kTerrNumSlash,
    kTerrNumBash,
    kTerrNumIce,
    kTerrNumCold,
    kTerrNumHot,
    kTerrNumFurniture
};

enum terrainBits {
    kTerrainNormal       = (1 << kTerrNumNormal), // clear terrain
    kTerrainEasy         = (1 << kTerrNumEasy),   // easy terrain (path)
    kTerrainRough        = (1 << kTerrNumRough),  // rough terrain (shrub)
    kTerrainStone        = (1 << kTerrNumStone),  // stone obstacle
    kTerrainWood         = (1 << kTerrNumWood),   // wood obstacle
    kTerrainHedge        = (1 << kTerrNumHedge),  // penetrable obstacle
    kTerrainTree         = (1 << kTerrNumTree),   // tree obstacle
    kTerrainWater        = (1 << kTerrNumWater),  // water (depth given by height)
    kTerrainFall         = (1 << kTerrNumFall),   // does not support things
    kTerrainRamp         = (1 << kTerrNumRamp),   // low friction slope
    kTerrainStair        = (1 << kTerrNumStair),  // high friction slope
    kTerrainLadder       = (1 << kTerrNumLadder), // vertical climb
    kTerrainObject       = (1 << kTerrNumObject), // collision with other object
    kTerrainActive       = (1 << kTerrNumActive), // tile is sensitive to walking on
    kTerrainSlash        = (1 << kTerrNumSlash),  // Slide Down Slope Left
    kTerrainBash         = (1 << kTerrNumBash),   // Slide Down Slope Left
    kTerrainIce          = (1 << kTerrNumIce),
    kTerrainCold         = (1 << kTerrNumCold),
    kTerrainHot          = (1 << kTerrNumHot),
    kTerrainFurniture    = (1 << kTerrNumFurniture)
};

//  A combination mask of all the terrain types which can have
//  sloped surfaces. (Water is a negative sloped surface)

const int           kTerrainSurface  = kTerrainNormal
                                      | kTerrainEasy
                                      | kTerrainRough
                                      | kTerrainWater
                                      | kTerrainRamp
                                      | kTerrainCold
                                      | kTerrainStair;

const int           kTerrainSolidSurface
    = kTerrainNormal
      | kTerrainEasy
      | kTerrainRough
      | kTerrainRamp
      | kTerrainCold
      | kTerrainStair;

//  A combination mask of all terrain types which can have
//  raised surfaces.

const int           kTerrainRaised   = kTerrainStone
                                      | kTerrainWood
                                      | kTerrainTree
                                      | kTerrainHedge
                                      | kTerrainFurniture;

const int           kTerrainSupportingRaised = kTerrainStone
        | kTerrainWood
        | kTerrainFurniture;

const int           kTerrainImpassable = kTerrainStone
                                        | kTerrainWood
                                        | kTerrainTree
                                        | kTerrainHedge
                                        | kTerrainFurniture;

const int           kTerrainSlow     = kTerrainRough
                                      | kTerrainWater
                                      | kTerrainLadder;

const int           kTerrainAverage  = kTerrainNormal
                                      | kTerrainRamp
                                      | kTerrainStair;

const int           kTerrainInsubstantial = kTerrainFall
        | kTerrainLadder
        | kTerrainSlash
        | kTerrainBash;

const int           kTerrainTransparent = kTerrainSurface
        | kTerrainInsubstantial;


/* ===================================================================== *
   Describes an individual tile
 * ===================================================================== */

struct TileInfo {
    uint32          offset;                 // offset in tile list
    TileAttrs       attrs;                  // tile attributes

    int32 combinedTerrainMask() {
        return (1 << attrs.fgdTerrain) | (1 << attrs.bgdTerrain);
    }

    bool hasProperty(const TileProperty &tileProp) {
        return tileProp.operator()(this);
    }

    static TileInfo *tileAddress(TileID id);
    static TileInfo *tileAddress(TileID id, uint8 **imageData);
};

/* ===================================================================== *
   Describes a bank of tiles
 * ===================================================================== */

class TileBank {
public:
    uint32          _numTiles;               // number of tiles in list
    TileInfo        *_tileArray;         // variable-sized array

    TileBank() {
        _numTiles = 0;
        _tileArray = nullptr;
    }

    TileBank(Common::SeekableReadStream *stream);
    ~TileBank();

    TileInfo *tile(uint16 index) {
        return &_tileArray[index];
    }
};


/* ===================================================================== *
   TileRef: This structure is used whenever a tile is positioned on a
   map or TAG. It contains the tile, the tile height, and various flags.
 * ===================================================================== */

struct TileRef {
    TileID tile;        // which tile
    uint8 flags;        // tile flags
    uint8 tileHeight;   // height of tile above platform
};

enum tileRefFlags {
    kTrTileTAG = (1 << 0),      // this tile part of a TAG
    kTrTileHidden = (1 << 1),   // tile hidden when covered
    kTrTileFlipped = (1 << 2),  // draw tile flipped horizontal
    kTrTileSensitive = (1 << 3) // tile is triggerable (TAG only)
};

typedef TileRef *TileRefPtr, **TileRefHandle;

void drawMainDisplay();

/* ===================================================================== *
   TileCycleData: This structure is used to define continuously cycling
   tiles such as waves on the ocean or a flickering torch.
 * ===================================================================== */

class TileCycleData {
public:
    int32           _counter;                // cycling counter
    uint8           _pad;                    // odd-byte pad
    uint8           _numStates,              // number of animated states
                    _currentState,           // current state of animation
                    _cycleSpeed;             // speed of cycling (0=none)

    TileID          _cycleList[16];        // array of tiles

    void load(Common::SeekableReadStream *stream) {
        _counter = stream->readSint32LE();
        _pad = stream->readByte();
        _numStates = stream->readByte();
        _currentState = stream->readByte();
        _cycleSpeed = stream->readByte();

        for (int i = 0; i < 16; ++i)
            _cycleList[i] = stream->readUint16LE();
    }
};

typedef TileCycleData *CyclePtr,            // pointer to cycle data
                     **CycleHandle;         // handle to cycle data

const int kMaxCycleRanges = 128;             // 128 should do for now...

/* ===================================================================== *
   ActiveTileItem: This is the base class for all of the behavioral
   objects which can be placed on a tilemap.
 * ===================================================================== */

enum ActiveItemTypes {
    kActiveTypeGroup = 0,
    kActiveTypeInstance
};

//  A pointer to the array of active item state arrays
extern byte **stateArray;

class ActiveItemList;

class ActiveItem;

#include "common/pack-start.h"

struct ActiveItemData {
    uint32 nextHashDummy;   // next item in hash chain
    uint16 scriptClassID;          // associated script object
    uint16 associationOffset;      // offset into association table
    uint8 numAssociations;        // number of associated items
    uint8 itemType;               // item type code.

    union {
        struct {
            uint16  grDataOffset;           // offset to group data
            uint8   numStates,              // number of animated states
                    uSize,                  // dimensions of group
                    vSize,
                    animArea,               // uSize * vSize
                    triggerWeight,          // sensitivity
                    pad;
            uint16  reserved0;
            uint16  reserved1;
        } group;

        struct {
            int16   groupID;                // id of defining group
            int16   u, v, h;
            uint16  stateIndex;             // for state-based anims.
            uint16  scriptFlags;
            uint16  targetU,                // U-coord of target
                    targetV;                // V-coord of target
            uint8   targetZ,                // Z-coord of target
                    worldNum;               // Add 0xf000 to get world Object ID
        } instance;
    };

    ActiveItem *aItem; // active item this ActiveItemData is a part of
} PACKED_STRUCT;

#include "common/pack-end.h"

class ActiveItem {
public:
    ActiveItem *_nextHash;      // next item in hash chain
    int _index;
    ActiveItemList *_parent;
    ActiveItemData _data;

    enum {
        kActiveItemLocked    = (1 << 8),     // The door is locked
        kActiveItemOpen      = (1 << 9),     // The door is open (not used)
        kActiveItemExclusive = (1 << 10)     // Script semaphore
    };

    ActiveItem(ActiveItemList *parent, int ind, Common::SeekableReadStream *stream);

    //  Return the map number of this active item
    int16 getMapNum();

    //  Return the address of an active item, given its ID
    static ActiveItem *activeItemAddress(ActiveItemID id);

    //  Return this active items ID
    ActiveItemID thisID();

    //  Return this active items ID
    ActiveItemID thisID(int16 mapNum);

    //  Return a pointer to this TAI's group
    ActiveItem *getGroup() {
        assert(_data.itemType == kActiveTypeInstance);
        return  activeItemAddress(ActiveItemID(getMapNum(), _data.instance.groupID));
    }

    enum BuiltInBehaviorType {
        kBuiltInNone = 0,                    // TAG handled by SAGA
        kBuiltInLamp,                        // TAG has lamp behavior
        kBuiltInDoor,                        // TAG has door behavior
        kBuiltInTransporter                  // TAG has transporter behavior
    };

    //  Return the state number of this active item instance
    uint8 getInstanceState(int16 mapNum) {
        return stateArray[mapNum][_data.instance.stateIndex];
    }

    //  Set the state number of this active item instance
    void setInstanceState(int16 mapNum, uint8 state) {
        stateArray[mapNum][_data.instance.stateIndex] = state;
    }

    uint8 builtInBehavior() {
        return (uint8)(_data.instance.scriptFlags >> 13);
    }

    //  Access to the locked bit
    bool isLocked() {
        return (bool)(_data.instance.scriptFlags & kActiveItemLocked);
    }
    void setLocked(bool val) {
        if (val)
            _data.instance.scriptFlags |= kActiveItemLocked;
        else
            _data.instance.scriptFlags &= ~kActiveItemLocked;
    }

    //  Access to the exclusion semaphore
    bool isExclusive() {
        return (bool)(_data.instance.scriptFlags & kActiveItemExclusive);
    }
    void setExclusive(bool val) {
        if (val)
            _data.instance.scriptFlags |= kActiveItemExclusive;
        else
            _data.instance.scriptFlags &= ~kActiveItemExclusive;
    }

    uint8 lockType() {
        return (uint8)_data.instance.scriptFlags;
    }

    //  ActiveItem instance methods
    bool use(ObjectID enactor);
    bool trigger(ObjectID enactor, ObjectID objID);
    bool release(ObjectID enactor, ObjectID objID);
    bool acceptLockToggle(ObjectID enactor, uint8 keyCode);

    bool inRange(const TilePoint &loc, int16 range);

    //  ActiveItem group methods
    bool use(ActiveItem *ins, ObjectID enactor);
    bool trigger(ActiveItem *ins, ObjectID enactor, ObjectID objID);
    bool release(ActiveItem *ins, ObjectID enactor, ObjectID objID);
    bool acceptLockToggle(ActiveItem *ins, ObjectID enactor, uint8 keyCode);

    bool inRange(ActiveItem *ins, const TilePoint &loc, int16 range) {
        return      loc.u >= ins->_data.instance.u - range
                    &&  loc.v >= ins->_data.instance.v - range
                    &&  loc.u <  ins->_data.instance.u + _data.group.uSize + range
                    &&  loc.v <  ins->_data.instance.v + _data.group.vSize + range;
    }

    ObjectID getInstanceContext();
    Location getInstanceLocation();

    static void playTAGNoise(ActiveItem *ai, int16 tagNoiseID);

};

typedef ActiveItem  *ActiveItemPtr,
        *ActiveItemHandle;

struct WorldMapData;

class ActiveItemList {
public:
    int _count;
    ActiveItem **_items;
    WorldMapData *_parent;

    ActiveItemList(WorldMapData *parent, int count, Common::SeekableReadStream *stream);
    ~ActiveItemList();
};

#if 0

/* ===================================================================== *
   TileHitZone: This object represents a large region which overlays the
   tile map without affecting it's appearance. It does not contain any
   tiles or animation information, it is a behavioral region only.
   It can be much larger and more complex in shape than an activity group.
 * ===================================================================== */

class TileHitZone : public ActiveItem {
public:

    //  REM: Allow discontiguous regions??
    int16           _numVertices;
    XArray<Point16> _vertexList;

    int16 type() {
        return activeTypeHitZone;
    }
};

class ObjectClass : public ActiveItem {
public:
    // A general type of object

    int16 type() {
        return activeTypeObjectType;
    }
};

class ObjectInstance : public ActiveItem {
public:
    TileGroupID     _classID;                // ID of object class

    // An instance of a specific object.

    uint16          _u, _v, _h;                // where the instance lies
    uint8           _facing;                 // which direction it's facing

    int16 type() {
        return activeTypeObject;
    }
};
#endif


/* ============================================================================ *
   TileActivityTask class
 * ============================================================================ */

//  This class handles the built-in movement of active terrain items. It
//  includes things like opening/closing doors, and toggling lamps.
//
//  Since most things in the game aren't moving at a given point, the
//  variables for simulating motion don't need to always be present.

class TileActivityTask {
    friend class    TileActivityTaskList;
    friend class    ActiveItem;

    uint8           _activityType;           // open or close
    uint8           _targetState;
    ActiveItem      *_tai;                   // the tile activity instance
    ThreadID        _script;                 // script to wake up when task done

    enum activityTypes {
        kActivityTypeNone,                   // no activity

        kActivityTypeOpen,                   // open door
        kActivityTypeClose,                  // close door

        kActivityTypeScript                  // scriptable activity
    };

    void remove();                   // tile activity task is finished.

public:

    //  Functions to create a new tile activity task.
    static void openDoor(ActiveItem &activeInstance);
    static void closeDoor(ActiveItem &activeInstance);
    static void doScript(ActiveItem &activeInstance, uint8 finalState, ThreadID id);

    static void updateActiveItems();

    static void initTileActivityTasks();

    static TileActivityTask *find(ActiveItem *tai);
    static bool setWait(ActiveItem *tai, ThreadID script);
};

/* ============================================================================ *
   TileActivityTaskList class
 * ============================================================================ */

class TileActivityTaskList {
    friend class    TileActivityTask;

public:
    Common::List<TileActivityTask *> _list;

    //  Constructor -- initial construction
    TileActivityTaskList();

    //  Reconstruct the TileActivityTaskList from an archive buffer
    TileActivityTaskList(Common::SeekableReadStream *stream);

    void read(Common::InSaveFile *in);
    void write(Common::MemoryWriteStreamDynamic *out);

    //  Cleanup this list
    void cleanup();

    // get new tile activity task
    TileActivityTask    *newTask(ActiveItem *activeInstance);
};

void moveActiveTerrain(int32 deltaTime);

/* ===================================================================== *
   A structure to record special return values from tileSlopeHeight
 * ===================================================================== */

struct StandingTileInfo {
    TileInfo        *surfaceTile;
    ActiveItemPtr   surfaceTAG;
    TileRef         surfaceRef;
    int16           surfaceHeight;
};

/* ======================================================================= *
   Platform struct
 * ======================================================================= */

const int           kMaxPlatforms = 8;

struct Platform {
    uint16          height,                 // height above ground
                    highestPixel;           // tallest tile upper extent
    uint16          flags;                  // platform flags
    TileRef         tiles[kPlatformWidth][kPlatformWidth];

    void load(Common::SeekableReadStream *stream) {
        height = stream->readUint16LE();
        highestPixel = stream->readUint16LE();
        flags = stream->readUint16LE();

        for (int j = 0; j < kPlatformWidth; ++j) {
            for (int i = 0; i < kPlatformWidth; ++i) {
                tiles[j][i].tile = stream->readUint16LE();
                tiles[j][i].flags = stream->readByte();
                tiles[j][i].tileHeight = stream->readByte();
            }
        }
    }

    TileRef &getTileRef(const TilePoint p) {
        return tiles[p.u][p.v];
    }

    TileRef &getTileRef(int16 u, int16 v) {
        return tiles[u][v];
    }

    //  fetch the REAL tile terrain info
    TileInfo *fetchTile(int16           mapNum,
                        const TilePoint &pt,
                        const TilePoint &origin,
                        int16           &height,
                        int16           &trFlags);

    //  Fetch the tile and the active item it came from...
    TileInfo *fetchTAGInstance(
        int16           mapNum,
        const TilePoint &pt,
        const TilePoint &origin,
        StandingTileInfo &sti);

    //  fetch the REAL tile terrain info and image data
    TileInfo *fetchTile(int16           mapNum,
                        const TilePoint &pt,
                        const TilePoint &origin,
                        uint8           **imageData,
                        int16           &height,
                        int16           &trFlags);

    //  Fetch the tile and image data and the active item it came from...
    TileInfo *fetchTAGInstance(
        int16           mapNum,
        const TilePoint &pt,
        const TilePoint &origin,
        uint8           **imageData,
        StandingTileInfo &sti);

    uint16   roofRipID() {
        return (uint16)(flags & 0x0FFF);
    }
};

typedef Platform    *PlatformPtr,
        * *PlatformHandle;

enum platformFlags {
    kPlCutaway = (1 << 0),                   // remove when player underneath

    //  Cutaway directions: When platform is cut away, also cut
    //  away any adjacent platforms in these directions.
    kPlVisible = (1 << 15),                      // platform is visible
    kPlModified = (1 << 14),                     // platform has been changed
    kPlCutUPos = (1 << 13),
    kPlCutUNeg = (1 << 13),
    kPlCutVPos = (1 << 13),
    kPlCutVNeg = (1 << 13)
};

#ifdef OLDPLATFLAAGS
enum platformFlags {
    kPlCutaway = (1 << 0),                   // remove when player underneath

    //  Cutaway directions: When platform is cut away, also cut
    //  away any adjacent platforms in these directions.

    kPlCutUPos = (1 << 1),
    kPlCutUNeg = (1 << 2),
    kPlCutVPos = (1 << 3),
    kPlCutVNeg = (1 << 4),

    kPlVisible = (1 << 5),                   // platform is visible
    kPlEnabled = (1 << 6)                    // enforce platform terrain.
};
#endif

/* ======================================================================= *
   PlatformCacheEntry struct
 * ======================================================================= */

struct PlatformCacheEntry {
    uint16          platformNum,            // original platform num
                    layerNum;               // index of this plat in mt.
    MetaTileID      metaID;                 // pointer to parent metatile
    Platform        pl;                     // actual platform data

    enum {
        kPlatformCacheSize = 256
    };
};

/* ======================================================================= *
   RipTable struct
 * ======================================================================= */

//  An object roof ripping "z-buffer" type structure

typedef int16       RipTableID;

struct RipTable {
    MetaTileID  metaID;
    uint16      ripID;
    int16       zTable[kPlatformWidth][kPlatformWidth];
    int _index;

    enum {
        kRipTableSize = 25
    };

    //  Constructor
    RipTable() : metaID(NoMetaTile), ripID(0), _index(-1) {
        for (int i = 0; i < kPlatformWidth; i++)
            for (int j = 0; j < kPlatformWidth; j++)
                zTable[i][j] = 0;
    }

    //  Return a pointer to a rip table, given the rip table's ID
    static RipTable *ripTableAddress(RipTableID id);

    //  Return the rip table's ID
    RipTableID thisID();
};

typedef RipTable    *RipTablePtr;
typedef RipTableID  *RipTableIDPtr,
                    **RipTableIDHandle;

typedef uint16 metaTileNoise;

/* ======================================================================= *
   MetaTile struct
 * ======================================================================= */

//  A "Metatile" is a larger tile made up of smaller tiles.

class MetaTileList;

class MetaTile {
public:
    uint16          _highestPixel;           // more drawing optimization
    BankBits        _banksNeeded;            // which banks are needed
    uint16          _stack[kMaxPlatforms];    // pointer to platforms
    uint32          _properties;             // more drawing optimization
    int             _index;
    MetaTileList   *_parent;

    MetaTile(MetaTileList *parent, int ind, Common::SeekableReadStream *stream);

    //  Return a pointer to a meta tile given its ID
    static MetaTile *metaTileAddress(MetaTileID id);

    //  Return this meta tile's ID
    MetaTileID thisID(int16 mapNum);

    //  Return a pointer to the specified platform
    Platform *fetchPlatform(int16 mapNum, int16 index);

    //  Return a pointer to this metatile's current object ripping
    //  table
    RipTable *ripTable(int16 mapNum);

    //  Return a reference to this meta tile's rip table ID
    RipTableID &ripTableID(int16 mapNum);

    metaTileNoise HeavyMetaMusic();

    bool hasProperty(
        const MetaTileProperty &metaTileProp,
        int16 mapNum,
        const TilePoint &mCoords) {
        return metaTileProp(this, mapNum, mCoords);
    }
};

typedef MetaTile    *MetaTilePtr,
        * *MetaTileHandle;

class MetaTileList {
public:
    int _count;
    MetaTile **_tiles;

    MetaTileList(int count, Common::SeekableReadStream *stream);
    ~MetaTileList();
};

/* ===================================================================== *
   MapHeader struct
 * ===================================================================== */

struct MapHeader {
    int16           size;                   // size of map
    int16           edgeType;               // edge type of map
    uint16          *mapData;           // start of map array

    MapHeader(Common::SeekableReadStream *stream);
    ~MapHeader();
};

enum mapEdgeTypes {
    kEdgeTypeBlack = 0,
    kEdgeTypeFill0,
    kEdgeTypeFill1,
    kEdgeTypeRepeat,
    kEdgeTypeWrap
};

typedef MapHeader   *MapPtr,
        * *MapHandle;

/* ===================================================================== *
   WorldMapData struct
 * ===================================================================== */

const uint16            kMetaTileVisited = (1 << 15);

struct WorldMapData {
    ObjectID            worldID;            //  The number of this map

    MapPtr              map;                //  Map data
    MetaTileList        *metaList;          //  MetaTile list
    TileRefPtr          activeItemData;     //  ActiveItem tileRefs
    ActiveItemList      *activeItemList;    //  ActiveItem list
    uint16              *assocList;          //  Associations
    RipTableIDPtr       ripTableIDList;     //  MetaTile object ripping

    ActiveItem          *instHash[513];   //  ActiveItem hash table

    int16               metaCount,          //  Number of MetaTiles
                        activeCount;        //  Number of ActiveItems
    int16               mapSize;            //  Size of map in meta tiles
    int32               mapHeight;          //  Height of map in Y


    //  Lookup metatile on map.
    MetaTilePtr lookupMeta(TilePoint coords);

    //  Build active item instance hash table
    void buildInstanceHash();

    //  Return a pointer to an active item instance based upon the
    //  group ID and the MetaTile's coordinates
    ActiveItem *findHashedInstance(TilePoint &tp, int16 group);
};

/* ===================================================================== *
   MetaTileIterator class
 * ===================================================================== */

class MetaTileIterator {
    TilePoint   _mCoords;
    TileRegion  _region;

    int16       _mapNum;

    bool iterate();

public:
    MetaTileIterator(int16 map, const TileRegion &reg) : _mapNum(map) {
        _region.min.u = reg.min.u >> kPlatShift;
        _region.max.u = (reg.max.u + kPlatMask) >> kPlatShift;
        _region.min.v = reg.min.v >> kPlatShift;
        _region.max.v = (reg.max.v + kPlatMask) >> kPlatShift;
        _region.min.z = _region.max.z = 0;
    }

    MetaTile *first(TilePoint *loc = NULL);
    MetaTile *next(TilePoint *loc = NULL);

    int16 getMapNum() {
        return _mapNum;
    }
};

/* ===================================================================== *
   TileIterator class
 * ===================================================================== */

class TileIterator {
    MetaTileIterator    _metaIter;
    MetaTile            *_mt;
    int16               _platIndex;
    Platform            *_platform;
    TilePoint           _tCoords,
                        _origin;
    TileRegion          _region,
                        _tCoordsReg;

    bool iterate();

public:
    TileIterator(int16 mapNum, const TileRegion &reg) :
        _metaIter(mapNum, reg),
        _region(reg) {
            _mt = nullptr;
            _platIndex = 0;
            _platform = nullptr;
    }

    TileInfo *first(TilePoint *loc, StandingTileInfo *stiResult = NULL);
    TileInfo *next(TilePoint *loc, StandingTileInfo *stiResult = NULL);
};

/* ===================================================================== *
   Exports
 * ===================================================================== */

extern StaticTilePoint viewCenter;             // coordinates of view on map

//  These two variables define which sectors overlap the view rect.

extern uint16       rippedRoofID;

/* ===================================================================== *
   Prototypes
 * ===================================================================== */

//  Initialize map data
void initMaps();

//  Cleanup map data
void cleanupMaps();

void setCurrentMap(int mapNum);              // set which map is current

//  Initialize the platform cache
void initPlatformCache();

//  Initialize the tile activity task list
void initTileTasks();

void saveTileTasks(Common::OutSaveFile *outS);
void loadTileTasks(Common::InSaveFile *in, int32 chunkSize);

//  Cleanup the tile activity task list
void cleanupTileTasks();

TilePoint getClosestPointOnTAI(ActiveItem *TAI, GameObject *obj);

void initActiveItemStates();
void saveActiveItemStates(Common::OutSaveFile *outS);
void loadActiveItemStates(Common::InSaveFile *in);
void cleanupActiveItemStates();

void initTileCyclingStates();
void saveTileCyclingStates(Common::OutSaveFile *outS);
void loadTileCyclingStates(Common::InSaveFile *in);
void cleanupTileCyclingStates();

void initAutoMap();
void saveAutoMap(Common::OutSaveFile *outS);
void loadAutoMap(Common::InSaveFile *in, int32 chunkSize);
inline void cleanupAutoMap() { /* nothing to do */ }

//  Determine if a platform is ripped
inline bool platformRipped(Platform *pl) {
    if (rippedRoofID != 0)
        return pl->roofRipID() == rippedRoofID;

    return false;
}

//  Compute visible area in U/V coords
TilePoint XYToUV(const Point32 &pt);
void TileToScreenCoords(const TilePoint &tp, Point16 &p);
void TileToScreenCoords(const TilePoint &tp, StaticPoint16 &p);

//  Determine height of point on a tile based on four corner heights
int16 ptHeight(const TilePoint &tp, uint8 *cornerHeight);


/* --------------------------------------------------------------------- *
   Prototypes for TERRAIN.CPP moved to terrain.h
 * --------------------------------------------------------------------- */


//  Determine which roof is above object
uint16 objRoofID(GameObject *obj);
uint16 objRoofID(GameObject *obj, int16 objMapNum, const TilePoint &objCoords);

//  Determine if roof over an object is ripped
bool objRoofRipped(GameObject *obj);

//  Determine if two objects are both under the same roof
bool underSameRoof(GameObject *obj1, GameObject *obj2);

//  Determine the distance between a point and a line
uint16 lineDist(
    const TilePoint &p1,
    const TilePoint &p2,
    const TilePoint &m);

/* ============================================================================ *
   Misc prototypes
 * ============================================================================ */

//  Converts Local XY to UV coordinates
StaticTilePoint pickTilePos(Point32 pos, const TilePoint &protagPos);
StaticTilePoint pickTile(Point32 pos,
                   const TilePoint &protagPos,
                   StaticTilePoint *floor = NULL,
                   ActiveItemPtr *pickTAI = NULL);

//  Function to select a nearby site
TilePoint selectNearbySite(
    ObjectID        worldID,
    const TilePoint &startingCoords,
    int32           minDist,
    int32           maxDist,
    bool            offScreenOnly = false);     // true if we want it off-screen

void drawMetaTiles(gPixelMap &drawMap);

} // end of namespace Saga2

#endif