YiTextEngine.h

Go to the documentation of this file.

// © You i Labs Inc. 2000-2017. All rights reserved.
#ifndef _YI_TEXT_ENGINE_H_
#define _YI_TEXT_ENGINE_H_

#include "framework/YiPredef.h"
#include "graphics/YiAbstractTextAtlas.h"
#include "graphics/YiBitmap.h"
#include "utility/YiColor.h"
#include "utility/YiString.h"
#include "renderer/YiMaterial.h"

#include <glm/gtc/type_ptr.hpp>

class CYIGenericFontRegistry;
class CYISDFTextAtlas;
class CYITextAtlas;
class CYITextLayout;
class CYITextRenderer;


#define YI_TEXT_LEFT            0x00000001
#define YI_TEXT_CENTER_H        0x00000002
#define YI_TEXT_RIGHT           0x00000004
#define YI_TEXT_ELLIPSES        0x00000008
#define YI_TEXT_MULTILINE       0x00000010
#define YI_TEXT_USER_WIDTH      0x00000020
#define YI_TEXT_FONT_TABLES     0x00000040

struct YI_TEXT_HEIGHT
{
    float fHeightAboveBase;
    float fHeightBelowBase;
    float fTrueBaseOffset;
    float fLowercaseLHeightAboveBase;

    bool operator<(YI_TEXT_HEIGHT const& other) const;
    bool operator==(YI_TEXT_HEIGHT const& other) const;
};

struct YI_FONT_INFO
{
    ssize_t nEngineID;
    CYIString filename;
    CYIString name;
    CYIString family;
    CYIString style;
};

enum YI_SCRIPT_MODE
{
    YI_SCRIPT_MODE_REGULAR,
    YI_SCRIPT_MODE_SUBSCRIPT,
    YI_SCRIPT_MODE_SUPERSCRIPT
};

enum YI_FONT_STYLE
{
    YI_FONT_STYLE_BOLD,
    YI_FONT_STYLE_BOLD_ITALIC,
    YI_FONT_STYLE_ITALIC,
    YI_FONT_STYLE_REGULAR
};

enum YI_TEXT_LINE_STYLE
{
    YI_TEXT_LINE_STYLE_UNDERLINE,
    YI_TEXT_LINE_STYLE_NONE
};

struct YI_TEXT_STYLE
{
    YI_TEXT_STYLE();

    ssize_t nFontID;
    float fFontSize;
    float fLeading;
    YI_SCRIPT_MODE eScriptMode;
    float fBaselineShift;
    float fTracking;
    float fKerning;
    CYIColor Color;
    YI_TEXT_LINE_STYLE eTextLineStyle;

    uint32_t uLastCodepointIndex;

    bool operator<(YI_TEXT_STYLE const& other) const;
    bool operator==(YI_TEXT_STYLE const& other) const;
};

struct YI_TEXT_RENDER_INFO
{
    YI_TEXT_RENDER_INFO();
    YI_TEXT_RENDER_INFO(uint32_t uFlags, float fOffsetX, float fYScale, const YI_FLOAT_RECT &rect, const CYIString &text, const std::vector<YI_TEXT_STYLE> &styles);

    /*
     If you update this structure, make sure to update the comparison operators.
    */
    uint32_t uFlags;
    float fOffsetX;
    float fYScale;
    YI_FLOAT_RECT rect;
    CYIString  text;

    std::vector<YI_TEXT_STYLE> styles;
    
    /* Comparator used by the \a std::map. */
    bool operator<(YI_TEXT_RENDER_INFO const& other) const;

    /*
     This function should be kept up to date with any field that would cause
     a relayout.
     */
    bool operator==(const YI_TEXT_RENDER_INFO &other) const;
    bool operator!=(const YI_TEXT_RENDER_INFO &other) const;

};

class CYITextEngine
{
public:
    static const uint32_t g_uTextEllipsisCodepointIndex;

    static const float g_fLineSpacingFactor;

    CYITextEngine();
    virtual ~CYITextEngine();

    bool Init(uint16_t nMaxFonts, uint16_t uFontAtlasSize);

    bool IsInitialized();

    std::unique_ptr<CYITextLayout> CreateTextLayout() const;

    ssize_t GetFontId(const CYIString &fontName) const;

    ssize_t GetFontId(const CYIString &fontFamilyName, const CYIString &fontStyleName, bool bIgnoreCase = false) const;

    ssize_t GetFontIdFromNameAndStyle(const CYIString &fontName, const CYIString &fontStyleName, bool bIgnoreCase = false) const;

    const YI_FONT_INFO &GetFontInfo(ssize_t nFontID) const;

    std::vector<CYIString> GetFontStyles(ssize_t nFontID) const;

    std::vector<CYIString> GetFontStyles(const CYIString &fontFamilyName) const;

    std::vector<CYIString> ReadFontStyles(const CYIString &url) const;

    std::vector<CYIString> ReadFontStyles(const uint8_t *pFontData, uint32_t uDataSize) const;

    ssize_t AddFont(const CYIString &URL);

    ssize_t AddFont(const CYIString &URL, const CYIString &fontName);

    ssize_t AddFont(const CYIString &URL, const CYIString &fontName, const CYIString &fontStyle);

    ssize_t AddFontWithOverrides(const CYIString &URL, const CYIString &fontName, const CYIString &fontFamily, const CYIString &fontStyle);

    ssize_t AddFont(const uint8_t *pFontData, uint32_t uDataSize);

    bool IsFontInFile(const CYIString &familyName, const CYIString &styleName, const CYIString &URL);

    uint32_t GetNumFonts();

    YI_TEXT_HEIGHT GetTextHeight(ssize_t nFontID, int32_t nFontSize);

    bool RenderText(const CYITextLayout *pTextLayout,
                    CYIBitmap *pDest,
                    const YI_TEXT_RENDER_INFO &rTextRenderInfo,
                    const glm::vec2 &vRenderOffset,
                    const YI_FLOAT_RECT *pTextExtents = nullptr);

    int32_t RenderGlyphIntoAtlas(YI_GLYPH_DETAILS *pGlyph, CYIAbstractTextAtlas *pAtlas);

    uint32_t GetCharacterIndex(ssize_t nFontID, uint32_t uChar) const;

    int32_t GetIndexOfPosition(const CYITextLayout *pTextLayout, float fX, float fY, float fHorizontalPixelRatio, float fVerticalPixelRatio) const;

    YI_FLOAT_RECT GetRectForTextRange(const CYITextLayout *pTextLayout, int32_t nStartIndex, int32_t nEndIndex, float fHorizontalPixelRatio, float fVerticalPixelRatio) const;

    CYITextAtlas *GetTextAtlas();
    
    CYISDFTextAtlas *GetSDFTextAtlas();
    
    bool SetTextAtlas(CYITextAtlas *pAtlas);
    
    bool SetSDFTextAtlas(CYISDFTextAtlas *pAtlas);

    CYITextRenderer * GetTextRenderer();
    
    uint16_t GetFontAtlasSize() const;

    std::shared_ptr<const CYITextLayout> GetTextLayout(const YI_TEXT_RENDER_INFO &rTextInfo);

    void TryRemoveCachedTextLayout(const YI_TEXT_RENDER_INFO &rTextInfo);

    ssize_t FindFontByFamilyName(const CYIString &fontFamilyName, YI_FONT_STYLE fontStyle = YI_FONT_STYLE_REGULAR);

private:
    void AddFontPriv(ssize_t nFontID, const CYIString &filename, const CYIString &fontName, const CYIString &fontFamilyName, const CYIString &fontStyleName);

    std::vector<YI_FONT_INFO> m_fontsInfo;

    CYITextRenderer     *m_pTextRenderer;

    CYITextAtlas    *m_pTextAtlas;
    CYISDFTextAtlas *m_pSDFTextAtlas;

    std::map<YI_TEXT_RENDER_INFO, std::weak_ptr<const CYITextLayout>> m_layoutCacheMap;

    uint16_t m_uFontAtlasSize;

    std::map<CYIString, ssize_t> m_fontFamilyCache;

    CYIGenericFontRegistry *m_pGenericFontRegistry;

    YI_DISALLOW_COPY_AND_ASSIGN(CYITextEngine)
};

#endif // _YI_TEXT_ENGINE_H_