PdfFontMetrics.h

// SPDX-FileCopyrightText: 2005 Dominik Seichter <domseichter@web.de>
// SPDX-FileCopyrightText: 2020 Francesco Pretto <ceztko@gmail.com>
// SPDX-License-Identifier: LGPL-2.0-or-later OR MPL-2.0
 
#ifndef PDF_FONT_METRICS_H
#define PDF_FONT_METRICS_H
 
#include "PdfString.h"
#include "PdfCMapEncoding.h"
#include "PdfCIDToGIDMap.h"
#include <podofo/auxiliary/Matrix.h>
#include <podofo/auxiliary/Corners.h>
 
FORWARD_DECLARE_FREETYPE();
 
namespace PoDoFo {
 
class PdfFontMetrics;
 
// NOTE: Underlying type may change in the future
using GlyphMetricsListConstPtr = std::shared_ptr<const std::vector<double>>;
 
using PdfFontMetricsConstPtr = std::shared_ptr<const PdfFontMetrics>;
 
class PODOFO_API PdfFontMetrics
{
    friend class PdfFont;
    friend class PdfFontSimple;
    friend class PdfFontObject;
    friend class PdfFontManager;
    friend class PdfFontMetricsBase;
    friend class PdfFontMetricsFreetype;
    friend class PdfEncodingFactory;
    friend class PdfEncodingMapSimple;
    friend class PdfDifferenceEncoding;
    PODOFO_PRIVATE_FRIEND(class FontTrueTypeSubset);
 
private:
    PdfFontMetrics();
 
public:
    virtual ~PdfFontMetrics();
 
    static std::unique_ptr<const PdfFontMetrics> Create(const std::string_view& filepath, unsigned faceIndex = 0);
 
    static std::unique_ptr<const PdfFontMetrics> CreateFromBuffer(const bufferview& buffer, unsigned faceIndex = 0);
 
    unsigned GetGlyphCount() const;
 
    unsigned GetGlyphCount(PdfGlyphAccess access) const;
 
    double GetGlyphWidth(unsigned gid) const;
    bool TryGetGlyphWidth(unsigned gid, double& width) const;
 
    double GetGlyphWidth(unsigned gid, PdfGlyphAccess access) const;
    bool TryGetGlyphWidth(unsigned gid, PdfGlyphAccess access, double& width) const;
 
    virtual void SubstituteGIDs(std::vector<unsigned>& gids,
        std::vector<unsigned char>& backwardMap) const;
 
    virtual bool HasUnicodeMapping() const = 0;
 
    virtual bool TryGetGID(char32_t codePoint, unsigned& gid) const = 0;
 
    virtual double GetLineSpacing() const = 0;
 
    virtual double GetUnderlineThickness() const = 0;
 
    virtual double GetUnderlinePosition() const = 0;
 
    virtual double GetStrikeThroughPosition() const = 0;
 
    virtual double GetStrikeThroughThickness() const = 0;
 
    virtual PdfFontFileType GetFontFileType() const = 0;
 
    bool HasFontFileData() const;
 
    bufferview GetOrLoadFontFileData() const;
 
    virtual const PdfObject* GetFontFileObject() const;
 
    virtual unsigned GetFontFileLength1() const = 0;
 
    virtual unsigned GetFontFileLength2() const = 0;
 
    virtual unsigned GetFontFileLength3() const = 0;
 
    virtual std::string_view GetFontName() const = 0;
 
    virtual std::string_view GetFontNameRaw() const;
 
    virtual std::string_view GetFontFamilyName() const = 0;
 
    std::string_view GetFontFamilyNameSafe() const;
 
    [[deprecated("Use GetFontFamilyNameSafe() instead")]]
    std::string_view GeFontFamilyNameSafe() const;
 
    virtual unsigned char GetSubsetPrefixLength() const;
 
    std::string_view GetPostScriptNameRough() const;
 
    virtual PdfFontStretch GetFontStretch() const = 0;
 
    unsigned GetWeight() const;
    virtual int GetWeightRaw() const = 0;
 
    virtual bool TryGetFlags(PdfFontDescriptorFlags& value) const = 0;
    PdfFontDescriptorFlags GetFlags() const;
 
    virtual bool TryGetBoundingBox(Corners& value) const = 0;
    Corners GetBoundingBox() const;
 
    virtual bool TryGetItalicAngle(double& value) const = 0;
    double GetItalicAngle() const;
 
    virtual bool TryGetAscent(double& value) const = 0;
    double GetAscent() const;
 
    virtual bool TryGetDescent(double& value) const = 0;
    double GetDescent() const;
 
    virtual bool TryGetCapHeight(double& value) const = 0;
    double GetCapHeight() const;
 
    virtual bool TryGetStemV(double& value) const = 0;
    double GetStemV() const;
 
    /* /Leading (optional, default 0)
     */
    double GetLeading() const;
    virtual double GetLeadingRaw() const = 0;
 
    double GetXHeight() const;
    virtual double GetXHeightRaw() const = 0;
 
    double GetStemH() const;
    virtual double GetStemHRaw() const = 0;
 
    double GetAvgWidth() const;
    virtual double GetAvgWidthRaw() const = 0;
 
    double GetMaxWidth() const;
    virtual double GetMaxWidthRaw() const = 0;
 
    double GetDefaultWidth() const;
    virtual double GetDefaultWidthRaw() const = 0;
 
    PdfFontStyle GetStyle() const;
 
    virtual bool IsObjectLoaded() const;
 
    bool IsStandard14FontMetrics() const;
 
    virtual bool IsStandard14FontMetrics(PdfStandard14FontType& std14Font) const;
 
    virtual const Matrix& GetMatrix() const;
 
    bool IsType1Kind() const;
 
    bool IsTrueTypeKind() const;
 
    bool IsPdfSymbolic() const;
 
    bool IsPdfNonSymbolic() const;
 
    virtual std::unique_ptr<PdfCMapEncoding> CreateToUnicodeMap(const PdfEncodingLimits& limitHints) const;
 
#ifdef PODOFO_3RDPARTY_INTEROP_ENABLED
    virtual FT_Face GetFaceHandle() const = 0;
#endif // PODOFO_3RDPARTY_INTEROP_ENABLED
 
public:
    const std::string& GetFilePath() const { return m_FilePath; }
    unsigned GetFaceIndex() const { return m_FaceIndex; }
 
protected:
    virtual PdfFontType GetFontType() const;
 
    virtual std::string_view GetBaseFontName() const = 0;
 
    virtual bool getIsBoldHint() const = 0;
    virtual bool getIsItalicHint() const = 0;
    virtual const datahandle& GetFontFileDataHandle() const = 0;
 
    virtual unsigned GetGlyphCountFontProgram() const;
    virtual bool TryGetGlyphWidthFontProgram(unsigned gid, double& width) const;
    virtual void ExportType3GlyphData(PdfDictionary& fontDict, cspan<std::string_view> glyphs) const;
 
    bool HasParsedWidths() const;
 
    unsigned GetParsedWidthsCount() const;
 
    GlyphMetricsListConstPtr GetParsedWidths() const { return m_ParsedWidths; }
 
    void SetParsedWidths(GlyphMetricsListConstPtr&& parsedWidths);
 
private:
    static std::unique_ptr<const PdfFontMetrics> CreateFromFile(const std::string_view& filepath, unsigned faceIndex,
        const PdfFontMetrics* metrics, bool skipNormalization);
 
    static std::unique_ptr<const PdfFontMetrics> CreateFromBuffer(const bufferview& buffer, unsigned faceIndex,
        const PdfFontMetrics* metrics, bool skipNormalization);
 
    static std::unique_ptr<PdfFontMetrics> CreateFromFace(FT_Face face, std::unique_ptr<charbuff>&& buffer,
        const PdfFontMetrics* metrics, bool skipNormalization);
 
    std::unique_ptr<const PdfFontMetrics> CreateMergedMetrics(bool skipNormalization) const;
 
    PdfEncodingMapConstPtr GetDefaultEncoding(PdfCIDToGIDMapConstPtr& cidToGidMap) const;
    PdfEncodingMapConstPtr GetDefaultEncoding() const;
 
    PdfCIDToGIDMapConstPtr GetTrueTypeBuiltinCIDToGIDMap() const;
 
    PdfEncodingMapConstPtr getFontType1BuiltInEncoding(FT_Face face) const;
    void initFamilyFontNameSafe();
    PdfEncodingMapConstPtr getDefaultEncoding(bool tryFetchCidToGidMap, PdfCIDToGIDMapConstPtr& cidToGidMap) const;
 
private:
    PdfFontMetrics(const PdfFontMetrics& rhs) = delete;
    PdfFontMetrics& operator=(const PdfFontMetrics& rhs) = delete;
 
private:
    std::string m_FilePath;
    std::string m_FamilyFontNameSafe;
    GlyphMetricsListConstPtr m_ParsedWidths;
    nullable<PdfFontStyle> m_Style;
    unsigned m_FaceIndex;
};
 
class PODOFO_API PdfFontMetricsBase : public PdfFontMetrics
{
    friend class PdfFontMetricsStandard14;
    friend class PdfFontMetricsObject;
 
private:
    PdfFontMetricsBase();
 
public:
    ~PdfFontMetricsBase();
 
protected:
    const datahandle& GetFontFileDataHandle() const override final;
    FT_Face GetFaceHandle() const override final;
    virtual datahandle getFontFileDataHandle() const = 0;
 
private:
    bool m_dataInit;
    bool m_faceInit;
    datahandle m_Data;
    FT_Face m_Face;
};
 
 
 
};
 
#endif // PDF_FONT_METRICS_H