screen.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 KYRA_SCREEN_H
#define KYRA_SCREEN_H

#include "common/util.h"
#include "common/func.h"
#include "common/list.h"
#include "common/array.h"
#include "common/rect.h"
#include "common/rendermode.h"
#include "common/stream.h"
#include "common/ptr.h"
#include "common/error.h"

class OSystem;

namespace Graphics {
class FontSJIS;
} // End of namespace Graphics

namespace Kyra {

typedef Common::Functor0<void> UpdateFunctor;

class KyraEngine_v1;
class Screen;

struct ScreenDim {
    uint16 sx;
    uint16 sy;
    uint16 w;
    uint16 h;
    uint16 col1;
    uint16 col2;
    uint16 line;
    uint16 column;
};

class Font {
public:
    /* Font types
     * Currently, we actually only care about oneByte and twoByte, but
     * naming it like this makes it easier to extend if the need arises.
     */
    enum Type {
        kASCII = 0,
        kJIS_X0201,
        kSJIS,
        kBIG5,
        kJohab
    };

public:
    virtual ~Font() {}

    virtual bool load(Common::SeekableReadStream &file) = 0;

    virtual bool usesOverlay() const { return false; }

    virtual Type getType() const = 0;

    virtual int getHeight() const = 0;

    virtual int getWidth() const = 0;

    virtual int getCharWidth(uint16 c) const = 0;

    virtual int getCharHeight(uint16 c) const { return getHeight(); }

    virtual void setColorMap(const uint8 *src) = 0;

    virtual void set16bitColorMap(const uint16 *src) {}

    enum FontStyle {
        kStyleNone          =   0,
        kStyleLeftShadow    =   1   <<  0,
        kStyleBorder        =   1   <<  1,
        kStyleFat           =   1   <<  2,
        kStyleNarrow1       =   1   <<  3,
        kStyleNarrow2       =   1   <<  4,
        kStyleFullWidth     =   1   <<  5,
        kStyleForceOneByte  =   1   <<  6
    };

    virtual void setStyles(int styles) {}

    virtual void drawChar(uint16 c, byte *dst, int pitch, int bpp) const = 0;

    virtual void drawChar(uint16 c, byte *dst, int pitch, int xOffs, int yOffs) const {}
};

class DOSFont : public Font {
public:
    DOSFont();
    ~DOSFont() override { unload(); }

    bool load(Common::SeekableReadStream &file) override;
    Type getType() const override { return kASCII; }
    int getHeight() const override { return _height; }
    int getWidth() const override { return _width; }
    int getCharWidth(uint16 c) const override;
    void setColorMap(const uint8 *src) override { _colorMap = src; }
    void drawChar(uint16 c, byte *dst, int pitch, int) const override;

private:
    void unload();

    const uint8 *_colorMap;

    uint8 *_data;

    int _width, _height;

    int _numGlyphs;

    uint8 *_widthTable;
    uint8 *_heightTable;
    uint16 *_bitmapOffsets;
};

class AMIGAFont : public Font {
public:
    AMIGAFont();
    ~AMIGAFont() override { unload(); }

    bool load(Common::SeekableReadStream &file) override;
    Type getType() const override { return kASCII; }
    int getHeight() const override { return _height; }
    int getWidth() const override { return _width; }
    int getCharWidth(uint16 c) const override;
    void setColorMap(const uint8 *src) override {}
    void drawChar(uint16 c, byte *dst, int pitch, int) const override;

private:
    void unload();

    int _width, _height;

    struct Character {
        uint8 yOffset, xOffset, width;

        struct Graphics {
            uint16 width, height;
            uint8 *bitmap;
        } graphics;
    };

    Character _chars[255];
};

class SJISFont : public Font {
public:
    SJISFont(Common::SharedPtr<Graphics::FontSJIS> &font, const uint8 invisColor, bool is16Color, bool drawOutline, int extraSpacing);
    ~SJISFont() override {}

    bool usesOverlay() const override { return true; }
    Type getType() const override { return kSJIS; }

    bool load(Common::SeekableReadStream &) override { return true; }
    int getHeight() const override;
    int getWidth() const override;
    int getCharWidth(uint16 c) const override;
    void setColorMap(const uint8 *src) override;
    void setStyles(int style) override { _style = style; }
    void drawChar(uint16 c, byte *dst, int pitch, int) const override;

protected:
    const uint8 *_colorMap;
    Common::SharedPtr<Graphics::FontSJIS> _font;
    const bool _drawOutline;
    int _style;

private:
    const uint8 _invisColor;
    const bool _isTextMode;
    // We use this for cases where the font width returned by getWidth() or getCharWidth() does not match the original.
    // The original Japanese game versions use hard coded sjis font widths of 8 or 9. However, this does not necessarily
    // depend on whether an outline is used or not (neither LOL/PC-9801 nor LOL/FM-TOWNS use an outline, but the first
    // version uses a font width of 8 where the latter uses a font width of 9).
    const int _sjisWidthOffset;
};

class ChineseFont : public Font {
public:
    ChineseFont(int pitch, int renderWidth, int renderHeight, int spacingWidth, int spacingHeight, int extraSpacingWidth, int extraSpacingHeight);
    ~ChineseFont() override;

    virtual Type getType() const override { return kBIG5; }

    bool load(Common::SeekableReadStream &data) override;

    void setStyles(int styles) override { _border = (styles & kStyleBorder); }
    int getHeight() const override { return _spacingHeight + (_border ? _borderExtraSpacingHeight : 0); }
    int getWidth() const override { return _spacingWidth + (_border ? _borderExtraSpacingWidth : 0); }
    int getCharWidth(uint16 c) const override { return hasGlyphForCharacter(c) ? getWidth() : -1; }
    int getCharHeight(uint16 c) const override { return hasGlyphForCharacter(c) ? _renderHeight + (_border ? _borderExtraSpacingHeight : 0) : -1; }
    void setColorMap(const uint8 *src) override;
    void drawChar(uint16 c, byte *dst, int pitch, int) const override;

protected:
    uint32 getGlyphDataSize() const { return _glyphDataSize; }
    uint16 _textColor[2];
    bool _pixelColorShading;
    const uint8 *_colorMap;
    bool _border;

private:
    virtual bool hasGlyphForCharacter(uint16 c) const = 0;
    virtual uint32 getFontOffset(uint16 c) const = 0;
    virtual void processColorMap() = 0;

    const int _spacingWidth, _spacingHeight;
    const int _borderExtraSpacingWidth, _borderExtraSpacingHeight;
    const int _renderWidth, _renderHeight;

    const uint8 *_glyphData;
    uint32 _glyphDataSize;
    const uint16 _pitch;
};

class JohabFontLoK final : public Font {
public:
    JohabFontLoK(Font *&font8fat, const uint16 *lookupTable, uint32 lookupTableSize);
    ~JohabFontLoK() override;

    enum {
        kNumJongseong = 191,
        kNumJungseong = 85,
        kNumChoseong = 109
    };

    bool load(Common::SeekableReadStream &data) override;
    Type getType() const override { return kJohab; }
    int getHeight() const override { return _height; }
    int getWidth() const override { return _width; }
    int getCharWidth(uint16 c) const override;
    int getCharHeight(uint16 c) const override;
    void setColorMap(const uint8 *src) override;
    void drawChar(uint16 c, byte *dst, int pitch, int) const override;

private:
    const uint8 *createGlyph(uint16 chr) const;
    void processColorMap();
    void renderGlyph(byte *dst, const uint8 *glyph, uint8 col, int pitch) const;

    int _width, _height;
    const uint8 *_colorMap;

    Font *&_font8fat;
    const uint8 *_fileData;
    const uint8 *_glyphData[3];
    const uint16 *_2byteTables[7];
    uint8 *_glyphTemp;
};

class ChineseOneByteFontLoK final : public ChineseFont {
public:
    ChineseOneByteFontLoK(int pitch);
private:
    bool hasGlyphForCharacter(uint16 c) const override { return !(c & 0x80); }
    uint32 getFontOffset(uint16 c) const override { return (c & 0x7F) * 14; }
    void processColorMap() override;
};

class ChineseTwoByteFontLoK final : public ChineseFont {
public:
    ChineseTwoByteFontLoK(int pitch, const uint16 *lookupTable, uint32 lookupTableSize);
private:
    bool hasGlyphForCharacter(uint16 c) const override;
    uint32 getFontOffset(uint16 c) const override;
    void processColorMap() override;

    const uint16 *_lookupTable;
    uint32 _lookupTableSize;
};

class ChineseOneByteFontMR final : public ChineseFont {
public:
    ChineseOneByteFontMR(int pitch) : ChineseFont(pitch, 7, 14, 9, 14, 0, 2) {}
private:
    bool hasGlyphForCharacter(uint16 c) const override { return (c == 0x6187) || !(c & 0x80); }
    uint32 getFontOffset(uint16 c) const override { return ((c == 0x6187) ? 128 : (c & 0x7F)) * 14; }
    void processColorMap() override;
};

class ChineseTwoByteFontMR final : public ChineseFont {
public:
    ChineseTwoByteFontMR(int pitch) : ChineseFont(pitch, 15, 14, 18, 14, 0, 2) {}
private:
    bool hasGlyphForCharacter(uint16 c) const override { return (c != 0x6187) && (c & 0x80); }
    uint32 getFontOffset(uint16 c) const override;
    void processColorMap() override;
};

#ifdef ENABLE_LOL

class ChineseOneByteFontLoL final : public ChineseFont {
public:
    ChineseOneByteFontLoL(int pitch) : ChineseFont(pitch, 8, 14, 8, 16, 0, 0) { _pixelColorShading = false; }
    void setStyles(int styles) override {}

private:
    bool hasGlyphForCharacter(uint16 c) const override { return !(c & 0x80); }
    uint32 getFontOffset(uint16 c) const override { return (c & 0x7F) * 14; }
    void processColorMap() override;
};

class ChineseTwoByteFontLoL final : public ChineseFont {
public:
    ChineseTwoByteFontLoL(int pitch) : ChineseFont(pitch, 16, 14, 16, 16, 0, 0) { _pixelColorShading = false; }
    void setStyles(int styles) override {}

private:
    bool hasGlyphForCharacter(uint16 c) const override { return (c & 0x80) && getFontOffset(c) < getGlyphDataSize(); }
    uint32 getFontOffset(uint16 c) const override;
    void processColorMap() override;
};

#endif

class ChineseOneByteFontHOF final : public ChineseFont {
public:
    ChineseOneByteFontHOF(int pitch) : ChineseFont(pitch, 8, 14, 9, 15, 0, 0) {}
private:
    bool hasGlyphForCharacter(uint16 c) const override { return !(c & 0x80); }
    uint32 getFontOffset(uint16 c) const override { return (c & 0x7F) * 14; }
    void processColorMap() override;
};

class ChineseTwoByteFontHOF final : public ChineseFont {
public:
    ChineseTwoByteFontHOF(int pitch) : ChineseFont(pitch, 16, 14, 18, 15, 0, 0) {}
private:
    bool hasGlyphForCharacter(uint16 c) const override { return (c & 0x80); }
    uint32 getFontOffset(uint16 c) const override;
    void processColorMap() override;
};

class KoreanOneByteFontHOF final : public ChineseFont {
public:
    KoreanOneByteFontHOF(int pitch) : ChineseFont(pitch, 8, 9, 8, 10, 0, 0) {}
    Type getType() const override { return kJohab; }
private:
    bool hasGlyphForCharacter(uint16 c) const override { return !(c & 0x80); }
    uint32 getFontOffset(uint16 c) const override { return (c & 0x7F) * 9; }
    void processColorMap() override;
};

class KoreanTwoByteFontHOF final : public ChineseFont {
public:
    KoreanTwoByteFontHOF(int pitch) : ChineseFont(pitch, 10, 9, 10, 10, 0, 0) {}
    Type getType() const override { return kJohab; }
private:
    bool hasGlyphForCharacter(uint16 c) const override { return (c & 0x80); }
    uint32 getFontOffset(uint16 c) const override;
    void processColorMap() override;
};

class MultiSubsetFont final : public Font {
public:
    MultiSubsetFont(Common::Array<Font*> *subsets) : Font(), _subsets(subsets) {}
    ~MultiSubsetFont() override;
    Type getType() const override { return kBIG5; }

    // Caveat: This method will try to load a font into the first subset slot it finds.
    // It expects the load method of the subset font to return false if the slot has
    // already been filled. It will then try the next slot. So, unlike other fonts the
    // subset fonts cannot be allowed to call the load method as often as they want
    // (which we never did anyway - we only ever load each font exactly one time).
    // But this also means that different
    bool load(Common::SeekableReadStream &data) override;

    void setStyles(int styles) override;
    int getHeight() const override;
    int getWidth() const override;
    int getCharWidth(uint16 c) const override;
    int getCharHeight(uint16 c) const override;
    void setColorMap(const uint8 *src) override;
    void drawChar(uint16 c, byte *dst, int pitch, int) const override;

private:
    Common::Array<Font*> *_subsets;
};

class Palette {
public:
    Palette(const int numColors);
    ~Palette();

    enum {
        kVGABytesPerColor = 3,
        kPC98BytesPerColor = 3,
        kAmigaBytesPerColor = 2
    };

    void loadVGAPalette(Common::ReadStream &stream, int startIndex, int colors);

    void loadHiColorPalette(Common::ReadStream &stream, int startIndex, int colors);

    void loadEGAPalette(Common::ReadStream &stream, int startIndex, int colors);

    enum CGAIntensity {
        kIntensityLow = 0,
        kIntensityHigh = 1
    };

    void setCGAPalette(int palIndex, CGAIntensity intensity);

    void loadAmigaPalette(Common::ReadStream &stream, int startIndex, int colors);

    void loadPC98Palette(Common::ReadStream &stream, int startIndex, int colors);

    int getNumColors() const { return _numColors; }

    void clear();

    void fill(int firstCol, int numCols, uint8 value);

    void copy(const Palette &source, int firstCol = 0, int numCols = -1, int dstStart = -1);

    void copy(const uint8 *source, int firstCol, int numCols, int dstStart = -1);

    uint8 *fetchRealPalette() const;

    //XXX
    uint8 &operator[](const int index) {
        assert(index >= 0 && index <= _numColors * 3);
        return _palData[index];
    }

    const uint8 &operator[](const int index) const {
        assert(index >= 0 && index <= _numColors * 3);
        return _palData[index];
    }

    uint8 *getData() { return _palData; }
    const uint8 *getData() const { return _palData; }

private:
    uint8 *_palData;
    const int _numColors;

    static const uint8 _egaColors[];
    static const int _egaNumColors;
    static const uint8 _cgaColors[4][12];
    static const int _cgaNumColors;
};

class Screen {
public:
    enum {
        SCREEN_W = 320,
        SCREEN_H = 200,
        SCREEN_H_SEGA_NTSC = 224,
        SCREEN_PAGE_SIZE = 320 * 200 + 1024,
        SCREEN_OVL_SJIS_SIZE = 640 * 400,
        SCREEN_PAGE_NUM = 16,
        SCREEN_OVLS_NUM = 6,

        SCREEN_IDLEREFRESH_RESTART_MSEC = 250,
        SCREEN_IDLEREFRESH_RATE_MSEC = 16
    };

    enum CopyRegionFlags {
        CR_NO_P_CHECK = 0x01
    };

    enum DrawShapeFlags {
        kDRAWSHP_XFLIP          = 0x01,
        kDRAWSHP_YFLIP          = 0x02,
        kDRAWSHP_SCALE          = 0x04,
        kDRAWSHP_WINREL         = 0x10,
        kDRAWSHP_CENTER         = 0x20,
        kDRAWSHP_FADE           = 0x100,
        kDRAWSHP_PREDATOR       = 0x200,
        kDRAWSHP_COMPACT        = 0x400,
        kDRAWSHP_PRIORITY       = 0x800,
        kDRAWSHP_TRANSPARENT    = 0x1000,
        kDRAWSHP_BCKGRNDFADE    = 0x2000,
        kDRAWSHP_MORPH          = 0x4000,
        kDRAWSHP_COLOR          = 0x8000
    };

    enum FontId {
        FID_6_FNT = 0,
        FID_8_FNT,
        FID_9_FNT,
        FID_CRED6_FNT,
        FID_CRED8_FNT,
        FID_BOOKFONT_FNT,
        FID_GOLDFONT_FNT,
        FID_INTRO_FNT,
        FID_SJIS_FNT,
        FID_SJIS_TEXTMODE_FNT,
        FID_SJIS_LARGE_FNT,
        FID_SJIS_SMALL_FNT,
        FID_CHINESE_FNT,
        FID_KOREAN_FNT,
        FID_NUM
    };

    Screen(KyraEngine_v1 *vm, OSystem *system, const ScreenDim *dimTable, const int dimTableSize);
    virtual ~Screen();

    // init
    virtual bool init();
    virtual Common::Error setResolution();
    virtual void enableHiColorMode(bool enabled);

    // refresh
    int updateScreen();
    void updateBackendScreen(bool force);

    uint32 _idleUpdateTimer;

    // debug functions
    bool queryScreenDebug() const { return _debugEnabled; }
    bool enableScreenDebug(bool enable);

    // page cur. functions
    int setCurPage(int pageNum);
    void clearCurPage();

    void copyWsaRect(int x, int y, int w, int h, int dimState, int plotFunc, const uint8 *src,
                     int unk1, const uint8 *unkPtr1, const uint8 *unkPtr2);

    // page 0 functions
    void copyToPage0(int y, int h, uint8 page, uint8 *seqBuf);
    void shakeScreen(int times);

    // page functions
    void copyRegion(int x1, int y1, int x2, int y2, int w, int h, int srcPage, int dstPage, int flags=0);
    void copyPage(uint8 srcPage, uint8 dstPage);

    void copyRegionToBuffer(int pageNum, int x, int y, int w, int h, uint8 *dest);
    void copyBlockToPage(int pageNum, int x, int y, int w, int h, const uint8 *src);

    void shuffleScreen(int sx, int sy, int w, int h, int srcPage, int dstPage, int ticks, bool transparent);
    void fillRect(int x1, int y1, int x2, int y2, uint8 color, int pageNum = -1, bool xored = false);

    void clearPage(int pageNum);

    int getPagePixel(int pageNum, int x, int y);
    void setPagePixel(int pageNum, int x, int y, uint8 color);

    const uint8 *getCPagePtr(int pageNum) const;
    uint8 *getPageRect(int pageNum, int x, int y, int w, int h);

    // palette handling
    void fadeFromBlack(int delay=0x54, const UpdateFunctor *upFunc = 0);
    void fadeToBlack(int delay=0x54, const UpdateFunctor *upFunc = 0);

    virtual void fadePalette(const Palette &pal, int delay, const UpdateFunctor *upFunc = 0);
    virtual void getFadeParams(const Palette &pal, int delay, int &delayInc, int &diff);
    virtual int fadePalStep(const Palette &pal, int diff);

    void setPaletteIndex(uint8 index, uint8 red, uint8 green, uint8 blue);
    virtual void setScreenPalette(const Palette &pal);

    // SegaCD version
    // This is a somewhat hacky but probably least invasive way to
    // move the whole ingame screen output down a couple of lines.
    void transposeScreenOutputY(int yAdd);

    // AMIGA version only
    bool isInterfacePaletteEnabled() const { return _dualPaletteModeSplitY; }
    void enableDualPaletteMode(int splitY);
    void disableDualPaletteMode();

    virtual void getRealPalette(int num, uint8 *dst);
    Palette &getPalette(int num);
    void copyPalette(const int dst, const int src);

    // gui specific (processing on _curPage)
    void drawLine(bool vertical, int x, int y, int length, int color);
    void drawClippedLine(int x1, int y1, int x2, int y2, int color);
    virtual void drawShadedBox(int x1, int y1, int x2, int y2, int color1, int color2);
    void drawBox(int x1, int y1, int x2, int y2, int color);

    // font/text handling
    virtual bool loadFont(FontId fontId, const char *filename);
    FontId setFont(FontId fontId);

    int getFontHeight() const;
    int getFontWidth() const;

    int getCharWidth(uint16 c) const;
    int getCharHeight(uint16 c) const;
    int getTextWidth(const char *str, bool nextWordOnly = false);
    int getNumberOfCharacters(const char *str);

    void printText(const char *str, int x, int y, uint8 color1, uint8 color2, int pitch = -1);

    virtual void setTextColorMap(const uint8 *cmap) = 0;
    void setTextColor(const uint8 *cmap, int a, int b);
    void setTextColor16bit(const uint16 *cmap16);
    int setFontStyles(FontId fontId, int styles);

    const ScreenDim *getScreenDim(int dim) const;
    void modifyScreenDim(int dim, int x, int y, int w, int h);
    int screenDimTableCount() const { return _dimTableCount; }

    void setScreenDim(int dim);
    int curDimIndex() const { return _curDimIndex; }

    void setTextMarginRight(int x) { _textMarginRight = x; }
    uint16 _textMarginRight;
    bool _overdrawMargin;

    const ScreenDim *_curDim;

    Common::String _lineBreakChars;

    // shape handling
    uint8 *encodeShape(int x, int y, int w, int h, int flags);

    int setNewShapeHeight(uint8 *shape, int height);
    int resetShapeHeight(uint8 *shape);

    virtual void drawShape(uint8 pageNum, const uint8 *shapeData, int x, int y, int sd, int flags, ...);

    // mouse handling
    void hideMouse();
    void showMouse();
    bool isMouseVisible() const;
    virtual void setMouseCursor(int x, int y, const byte *shape);

    // rect handling
    virtual int getRectSize(int w, int h) = 0;

    void rectClip(int &x, int &y, int w, int h);

    // misc
    virtual void loadBitmap(const char *filename, int tempPage, int dstPage, Palette *pal, bool skip=false);

    virtual bool loadPalette(const char *filename, Palette &pal);
    bool loadPaletteTable(const char *filename, int firstPalette);
    virtual void loadPalette(const byte *data, Palette &pal, int bytes);

    void setAnimBlockPtr(int size);

    void setShapePages(int page1, int page2, int minY = -1, int maxY = 201);

    virtual byte getShapeFlag1(int x, int y);
    virtual byte getShapeFlag2(int x, int y);

    virtual int getDrawLayer(int x, int y);
    virtual int getDrawLayer2(int x, int y, int height);

    void blockInRegion(int x, int y, int width, int height);
    void blockOutRegion(int x, int y, int width, int height);

    int _charSpacing;
    int _lineSpacing;
    int _curPage;
    uint8 *_shapePages[2];
    int _maskMinY, _maskMaxY;
    FontId _currentFont;

    // decoding functions
    static void decodeFrame1(const uint8 *src, uint8 *dst, uint32 size);
    static uint16 decodeEGAGetCode(const uint8 *&pos, uint8 &nib);

    static void decodeFrame3(const uint8 *src, uint8 *dst, uint32 size, bool isAmiga);
    static uint decodeFrame4(const uint8 *src, uint8 *dst, uint32 dstSize);
    static void decodeFrameDelta(uint8 *dst, const uint8 *src, bool noXor = false);
    static void decodeFrameDeltaPage(uint8 *dst, const uint8 *src, const int pitch, bool noXor);

    static void convertAmigaGfx(uint8 *data, int w, int h, int depth = 5, bool wsa = false, int bytesPerPlane = -1);
    static void convertAmigaMsc(uint8 *data);

    // This seems to be a variant of shuffleScreen (which is used in LoK). At the time of coding (and long after that) the
    // fact that this is a double implementation went unnoticed. My - admittedly limited - efforts to get rid of one of these
    // implementations were unsatisfactory, though. Each method seems to be optimized to produce accurate results for its
    // specifc purpose (LoK for shuffleScreen, EoB/LoL for crossFadeRegion). Merging these methods has no priority, since we
    // can well afford the 20 lines of extra code.
    void crossFadeRegion(int x1, int y1, int x2, int y2, int w, int h, int srcPage, int dstPage);

    uint16 *get16bitPalette() { return _16bitPalette; }
    void set16bitShadingLevel(int lvl) { _16bitShadingLevel = lvl; }

protected:
    void resetPagePtrsAndBuffers(int pageSize);
    uint8 *getPagePtr(int pageNum);
    virtual void updateDirtyRects();
    void updateDirtyRectsAmiga();
    void updateDirtyRectsOvl();

    template<typename srcType, typename scaleToType> void scale2x(uint8 *dst, int dstPitch, const uint8 *src, int srcPitch, int w, int h);
    template<typename pixelType> void mergeOverlayImpl(int x, int y, int w, int h);
    virtual void mergeOverlay(int x, int y, int w, int h) {
        if (_useHiColorScreen)
            mergeOverlayImpl<uint16>(x, y, w, h);
        else
            mergeOverlayImpl<uint8>(x, y, w, h);
    }

    // overlay specific
    byte *getOverlayPtr(int pageNum);
    void clearOverlayPage(int pageNum);
    void clearOverlayRect(int pageNum, int x, int y, int w, int h);
    void copyOverlayRegion(int x, int y, int x2, int y2, int w, int h, int srcPage, int dstPage);

    // font/text specific
    uint16 fetchChar(const char *&s) const;
    void drawChar(uint16 c, int x, int y, int pitch = -1);

    int16 encodeShapeAndCalculateSize(uint8 *from, uint8 *to, int size);

    template<bool noXor> static void wrapped_decodeFrameDelta(uint8 *dst, const uint8 *src);
    template<bool noXor> static void wrapped_decodeFrameDeltaPage(uint8 *dst, const uint8 *src, const int pitch);

    uint8 *_pagePtrs[16];
    const uint8 *_pagePtrsBuff;
    uint8 *_sjisOverlayPtrs[SCREEN_OVLS_NUM];
    uint8 _pageMapping[SCREEN_PAGE_NUM];

    bool _useOverlays;
    bool _useSJIS;
    int _fontStyles;

    Font *_fonts[FID_NUM];
    uint8 _textColorsMap[16];
    uint16 _textColorsMap16bit[2];

    uint8 *_textRenderBuffer;
    int _textRenderBufferSize;

    Common::SharedPtr<Graphics::FontSJIS> _sjisFontShared;
    uint8 _sjisInvisibleColor;
    bool _sjisMixedFontMode;

    // colors/palette specific
    bool _use16ColorMode;
    bool _useShapeShading;
    bool _4bitPixelPacking;
    bool _useHiResEGADithering;
    bool _useHiColorScreen;
    bool _isAmiga;
    bool _useAmigaExtraColors;
    bool _isSegaCD;
    Common::RenderMode _renderMode;
    int _bytesPerPixel;
    int _screenPageSize;
    const int _screenHeight;
    int _yTransOffs;

    Palette *_screenPalette;
    Common::Array<Palette *> _palettes;
    Palette *_internFadePalette;

    uint16 shade16bitColor(uint16 col);

    uint16 *_16bitPalette;
    uint16 *_16bitConversionPalette;
    uint8 _16bitShadingLevel;

    uint8 *_animBlockPtr;
    int _animBlockSize;

    // dimension handling
    const ScreenDim *const _dimTable;
    ScreenDim **_customDimTable;
    const int _dimTableCount;
    int _curDimIndex;

    // mouse handling
    int _mouseLockCount;
    const uint8 _cursorColorKey;

    virtual void postProcessCursor(uint8 *data, int w, int h, int pitch) {}

    enum {
        kMaxDirtyRects = 50
    };

    bool _forceFullUpdate;
    bool _paletteChanged;
    Common::List<Common::Rect> _dirtyRects;

    void addDirtyRect(int x, int y, int w, int h);

    OSystem *_system;
    KyraEngine_v1 *_vm;

    // shape
    typedef void (Screen::*DsPlotFunc)(uint8*, uint8);
    typedef int (Screen::*DsMarginSkipFunc)(uint8*&, const uint8*&, int&);
    typedef void (Screen::*DsLineFunc)(uint8*&, const uint8*&, const DsPlotFunc, int&, int16);

    int drawShapeMarginNoScaleUpwind(uint8 *&dst, const uint8 *&src, int &cnt);
    int drawShapeMarginNoScaleDownwind(uint8 *&dst, const uint8 *&src, int &cnt);
    int drawShapeMarginScaleUpwind(uint8 *&dst, const uint8 *&src, int &cnt);
    int drawShapeMarginScaleDownwind(uint8 *&dst, const uint8 *&src, int &cnt);
    int drawShapeSkipScaleUpwind(uint8 *&dst, const uint8 *&src, int &cnt);
    int drawShapeSkipScaleDownwind(uint8 *&dst, const uint8 *&src, int &cnt);
    void drawShapeProcessLineNoScaleUpwind(uint8 *&dst, const uint8 *&src, const DsPlotFunc plot, int &cnt, int16);
    void drawShapeProcessLineNoScaleDownwind(uint8 *&dst, const uint8 *&src, const DsPlotFunc plot, int &cnt, int16);
    void drawShapeProcessLineScaleUpwind(uint8 *&dst, const uint8 *&src, const DsPlotFunc plot, int &cnt, int16 scaleState);
    void drawShapeProcessLineScaleDownwind(uint8 *&dst, const uint8 *&src, const DsPlotFunc plot, int &cnt, int16 scaleState);

    void drawShapePlotType0(uint8 *dst, uint8 cmd);
    void drawShapePlotType1(uint8 *dst, uint8 cmd);
    void drawShapePlotType3_7(uint8 *dst, uint8 cmd);
    void drawShapePlotType4(uint8 *dst, uint8 cmd);
    void drawShapePlotType5(uint8 *dst, uint8 cmd);
    void drawShapePlotType6(uint8 *dst, uint8 cmd);
    void drawShapePlotType8(uint8 *dst, uint8 cmd);
    void drawShapePlotType9(uint8 *dst, uint8 cmd);
    void drawShapePlotType11_15(uint8 *dst, uint8 cmd);
    void drawShapePlotType12(uint8 *dst, uint8 cmd);
    void drawShapePlotType13(uint8 *dst, uint8 cmd);
    void drawShapePlotType14(uint8 *dst, uint8 cmd);
    void drawShapePlotType16(uint8 *dst, uint8 cmd);
    void drawShapePlotType20(uint8 *dst, uint8 cmd);
    void drawShapePlotType21(uint8 *dst, uint8 cmd);
    void drawShapePlotType33(uint8 *dst, uint8 cmd);
    void drawShapePlotType37(uint8 *dst, uint8 cmd);
    void drawShapePlotType48(uint8 *dst, uint8 cmd);
    void drawShapePlotType52(uint8 *dst, uint8 cmd);

    const uint8 *_dsShapeFadingTable;
    int _dsShapeFadingLevel;
    const uint8 *_dsColorTable;
    const uint8 *_dsTransparencyTable1;
    const uint8 *_dsTransparencyTable2;
    const uint8 *_dsBackgroundFadingTable;
    int _dsDrawLayer;
    uint8 *_dsDstPage;
    int _dsTmpWidth;
    int _dsOffscreenLeft;
    int _dsOffscreenRight;
    int _dsScaleW;
    int _dsScaleH;
    int _dsOffscreenScaleVal1;
    int _dsOffscreenScaleVal2;
    int _drawShapeVar1;
    int _drawShapeVar3;
    int _drawShapeVar4;
    int _drawShapeVar5;

    // AMIGA version
    int _dualPaletteModeSplitY;

    // debug
    bool _debugEnabled;
};

} // End of namespace Kyra

#endif