palette.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/>.
 *
 */

#ifndef MADS_PALETTE_H
#define MADS_PALETTE_H

#include "common/scummsys.h"
#include "common/stream.h"

namespace MADS {
namespace Nebular {

class RexNebularEngine;

#define PALETTE_USAGE_COUNT 4

#define PALETTE_RESERVED_LOW_COUNT 18
#define PALETTE_RESERVED_HIGH_COUNT 10

constexpr int PALETTE_COUNT = 256;
constexpr int RGB_SIZE = 3;
constexpr int PALETTE_SIZE = (256 * 3);

enum {
    PALFLAG_BACKGROUND = 0x8000,  // Loading initial background
    PALFLAG_RESERVED = 0x4000,  // Enable mapping reserved colors
    PALFLAG_ANY_TO_CLOSEST = 0x2000,  // Any color can map to closest
    PALFLAG_ALL_TO_CLOSEST = 0x1000,  // Any colors that can map must map
    PALFLAG_TOP_COLORS = 0x0800,  // Allow mapping to high four colors
    PALFLAG_DEFINE_RESERVED = 0x0400,  // Define initial reserved color
    PALFLAG_MASK = 0xfc00   // Mask for all the palette flags
};

struct PaletteCycle {
    byte _colorCount;
    byte _firstListColor;
    byte _firstColorIndex;
    byte _ticks;

    PaletteCycle() {
        _colorCount = _firstListColor = _firstColorIndex = _ticks = 0;
    }
};

struct RGB6 {
    byte r;
    byte g;
    byte b;
    byte _palIndex;
    byte _u2;
    byte _flags;

    void load(Common::SeekableReadStream *f);
};

class PaletteUsage {
public:
    struct UsageEntry {
        uint16 _palIndex;
        int _sortValue;

        UsageEntry(int palIndex) {
            _palIndex = palIndex; _sortValue = -1;
        }
        UsageEntry() {
            _palIndex = 0; _sortValue = 0;
        }
    };
    struct UsageRange {
        byte _v1, _v2;

        UsageRange(byte v1, byte v2) {
            _v1 = v1; _v2 = v2;
        }
    };
private:
    RexNebularEngine *_vm;
    Common::Array<UsageEntry> *_data;

    int getGamePalFreeIndex(int *palIndex);

    int rgbFactor(byte *palEntry, RGB6 &pal6);

    Common::Array<UsageEntry> _nullUsage;
public:
    PaletteUsage(RexNebularEngine *vm);

    void load(Common::Array<UsageEntry> *data);

    bool empty() const {
        return _data == nullptr;
    }

    uint16 &operator[](int index) {
        return (*_data)[index]._palIndex;
    }

    void setEmpty() {
        _data = &_nullUsage;
    }

    void getKeyEntries(Common::Array<RGB6> &palette);

    void prioritize(Common::Array<RGB6> &palette);

    int process(Common::Array<RGB6> &palette, uint flags);

    void transform(Common::Array<RGB6> &palette);

    void updateUsage(Common::Array<int> &usageList, int sceneUsageIndex);

    void resetPalFlags(int idx);

    int checkRGB(const byte *rgb, int palStart, bool flag, int *palIndex);
};

class RGBList {
private:
    bool _data[32];
public:
    RGBList() {
        clear();
    }

    void clear();

    void reset();

    void copy(RGBList &src);

    int scan();

    bool &operator[](int idx) {
        return _data[idx];
    }
};

class Fader {
public:
    struct GreyEntry {
        byte _intensity;
        byte _mapColor;
        uint16 _accum[3];
    };
private:
    void mapToGreyRamp(byte palette[PALETTE_SIZE], int baseColor, int numColors,
        int baseGrey, int numGreys, GreyEntry *map);

    void getGreyValues(const byte palette[PALETTE_SIZE], byte greyList[PALETTE_COUNT],
        int baseColor, int numColors);

    void greyPopularity(const byte greyList[PALETTE_COUNT], byte greyTable[64], int numColors);

    void insertionSort(int size, byte *id, byte *value);
protected:
    RexNebularEngine *_vm;
    byte _rgb64Map[PALETTE_COUNT];
public:
    bool _colorFlags[4];
    int _colorValues[4];
public:
    Fader(RexNebularEngine *vm);

    void setPalette(const byte *colors, uint start, uint num);

    void grabPalette(byte *colors, uint start, uint num);

    void getFullPalette(byte palette[PALETTE_SIZE]);

    void setFullPalette(byte palette[PALETTE_SIZE]);

    int rgbMerge(byte r, byte g, byte b);

    int rgbMerge(RGB6 &palEntry);

    void fadeOut(byte palette[PALETTE_SIZE], byte *paletteMap,
        int baseColor, int numColors, int baseGrey, int numGreys,
        int tickDelay, int steps);

    void fadeIn(byte palette[PALETTE_SIZE], byte destPalette[PALETTE_SIZE],
        int baseColor, int numColors, int baseGrey, int numGreys,
        int tickDelay, int steps);
};

class Palette : public Fader {
private:
    void initVGAPalette(byte *palette);
public:
    byte _mainPalette[PALETTE_SIZE];
    byte _cyclingPalette[PALETTE_SIZE];
    uint32 _palFlags[PALETTE_COUNT];
    PaletteUsage _paletteUsage;
    RGBList _rgbList;
    bool _lockFl;
    int _lowRange;
    int _highRange;
public:
    Palette(RexNebularEngine *vm);

    virtual ~Palette() {
    }

    void setEntry(byte palIndex, byte r, byte g, byte b);

    uint8 palIndexFromRgb(byte r, byte g, byte b, byte *paletteData = nullptr);

    void setSystemPalette();

    static void setGradient(byte *palette, int start, int count, int rgbValue1, int rgbValue2);

    void resetGamePalette(int lowRange, int highRange);

    void initPalette();

    void setLowRange();

    void setColorFlags(byte r, byte g, byte b);
    void setColorValues(byte r, byte g, byte b);

    void lock();
    void unlock();

    void refreshSceneColors();

    static int closestColor(const byte *matchColor, const byte *refPalette,
        int paletteInc, int count);
};

} // namespace Nebular
} // namespace MADS

#endif