openmw-tes3mp/components/esm/loadland.hpp

#ifndef OPENMW_ESM_LAND_H
#define OPENMW_ESM_LAND_H

#include <stdint.h>

#include "esmcommon.hpp"

namespace ESM
{

class ESMReader;
class ESMWriter;

/*
 * Landscape data.
 */

struct Land
{
    static unsigned int sRecordId;

    Land();
    ~Land();

    int mFlags; // Only first four bits seem to be used, don't know what
    // they mean.
    int mX, mY; // Map coordinates.
    int mPlugin; // Plugin index, used to reference the correct material palette.

    // File context. This allows the ESM reader to be 'reset' to this
    // location later when we are ready to load the full data set.
    ESMReader* mEsm;
    ESM_Context mContext;

    bool mHasData;
    int mDataTypes;
    int mDataLoaded;

    enum
    {
        DATA_VNML = 1,
        DATA_VHGT = 2,
        DATA_WNAM = 4,
        DATA_VCLR = 8,
        DATA_VTEX = 16
    };

    // number of vertices per side
    static const int LAND_SIZE = 65;

    // cell terrain size in world coords
    static const int REAL_SIZE = 8192;

    // total number of vertices
    static const int LAND_NUM_VERTS = LAND_SIZE * LAND_SIZE;

    static const int HEIGHT_SCALE = 8;

    //number of textures per side of land
    static const int LAND_TEXTURE_SIZE = 16;

    //total number of textures per land
    static const int LAND_NUM_TEXTURES = LAND_TEXTURE_SIZE * LAND_TEXTURE_SIZE;

#pragma pack(push,1)
    struct VHGT
    {
        float mHeightOffset;
        int8_t mHeightData[LAND_NUM_VERTS];
        short mUnk1;
        char mUnk2;
    };
#pragma pack(pop)

    typedef signed char VNML;

    struct LandData
    {
        float mHeightOffset;
        float mHeights[LAND_NUM_VERTS];
        VNML mNormals[LAND_NUM_VERTS * 3];
        uint16_t mTextures[LAND_NUM_TEXTURES];

        bool mUsingColours;
        char mColours[3 * LAND_NUM_VERTS];
        int mDataTypes;

        // WNAM appears to contain the global map image for this cell. Probably a palette-based format,
        // since there's only 1 byte for each pixel.
        // Currently unused (global map is drawn on the fly in OpenMW, takes ~1/2 second at startup for Morrowind.esm).
        // The problem with using the original data is that we would need to exactly replicate the TES CS's algorithm
        // for drawing the global map in OpenCS, in order to get seamless edges when creating landmass mods.
        uint8_t mWnam[81];
        short mUnk1;
        uint8_t mUnk2;

        void save(ESMWriter &esm);
        static void transposeTextureData(uint16_t *in, uint16_t *out);
    };

    LandData *mLandData;

    void load(ESMReader &esm);
    void save(ESMWriter &esm) const;

    void blank() {}

    /**
     * Actually loads data
     */
    void loadData(int flags);

    /**
     * Frees memory allocated for land data
     */
    void unloadData();

    /// Check if given data type is loaded
    /// \todo reimplement this
    bool isDataLoaded(int flags) {
        return (mDataLoaded & flags) == flags;
    }

    private:
        Land(const Land& land);
        Land& operator=(const Land& land);

        /// Loads data and marks it as loaded
        /// \return true if data is actually loaded from file, false otherwise
        /// including the case when data is already loaded
        bool condLoad(int flags, int dataFlag, void *ptr, unsigned int size);
};

}
#endif