axmol/cocos/2d/CCFontFreeType.cpp

/****************************************************************************
Copyright (c) 2013      Zynga Inc.
Copyright (c) 2013-2016 Chukong Technologies Inc.
Copyright (c) 2017-2018 Xiamen Yaji Software Co., Ltd.
Copyright (c) 2021 Bytedance Inc.

https://adxe.org

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
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The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
****************************************************************************/

#include "2d/CCFontFreeType.h"

#include "freetype/ftfntfmt.h"

#include FT_BBOX_H
#include "2d/CCFontAtlas.h"
#include "base/CCDirector.h"
#include "base/ccUTF8.h"
#include "freetype/internal/tttypes.h"
#include "platform/CCFileUtils.h"
#include "platform/CCFileStream.h"

NS_CC_BEGIN

FT_Library FontFreeType::_FTlibrary;
bool FontFreeType::_FTInitialized           = false;
bool FontFreeType::_streamParsingEnabled    = false;
bool FontFreeType::_doNativeBytecodeHinting = true;
const int FontFreeType::DistanceMapSpread   = 6;

const char* FontFreeType::_glyphASCII =
    "\"!#$%&'()*+,-./"
    "0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~"
    "¡¢£¤¥¦§¨©ª«¬­®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþ ";
const char* FontFreeType::_glyphNEHE =
    "!\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~ ";

typedef struct _DataRef
{
    Data data;
    unsigned int referenceCount = 0;
} DataRef;

static std::unordered_map<std::string, DataRef> s_cacheFontData;

// ------ freetype2 stream parsing support ---
static unsigned long ft_stream_read_callback(FT_Stream stream,
                                             unsigned long offset,
                                             unsigned char* buf,
                                             unsigned long size)
{
    auto fd = (FileStream*)stream->descriptor.pointer;
    if (!fd)
        return 1;
    if (!size && offset >= stream->size)
        return 1;

    if (stream->pos != offset)
        fd->seek(offset, SEEK_SET);

    if (buf)
        return fd->read(buf, size);

    return 0;
}

static void ft_stream_close_callback(FT_Stream stream)
{
    const auto* fd = (FileStream*)stream->descriptor.pointer;
    delete fd;
    stream->size               = 0;
    stream->descriptor.pointer = nullptr;
}

FontFreeType* FontFreeType::create(const std::string& fontName,
                                   float fontSize,
                                   GlyphCollection glyphs,
                                   const char* customGlyphs,
                                   bool distanceFieldEnabled /* = false */,
                                   float outline /* = 0 */)
{
    FontFreeType* tempFont = new (std::nothrow) FontFreeType(distanceFieldEnabled, outline);

    if (!tempFont)
        return nullptr;

    tempFont->setGlyphCollection(glyphs, customGlyphs);

    if (!tempFont->createFontObject(fontName, fontSize))
    {
        delete tempFont;
        return nullptr;
    }
    tempFont->autorelease();
    return tempFont;
}

bool FontFreeType::initFreeType()
{
    if (_FTInitialized == false)
    {
        // begin freetype
        if (FT_Init_FreeType(&_FTlibrary))
            return false;

        const FT_Int spread = DistanceMapSpread;
        FT_Property_Set(_FTlibrary, "sdf", "spread", &spread);
        FT_Property_Set(_FTlibrary, "bsdf", "spread", &spread);

        _FTInitialized = true;
    }

    return _FTInitialized;
}

void FontFreeType::shutdownFreeType()
{
    if (_FTInitialized == true)
    {
        FT_Done_FreeType(_FTlibrary);
        s_cacheFontData.clear();
        _FTInitialized = false;
    }
}

FT_Library FontFreeType::getFTLibrary()
{
    initFreeType();
    return _FTlibrary;
}

// clang-format off
FontFreeType::FontFreeType(bool distanceFieldEnabled /* = false */, float outline /* = 0 */)
: _fontFace(nullptr)
, _stroker(nullptr)
, _encoding(FT_ENCODING_UNICODE)
, _distanceFieldEnabled(distanceFieldEnabled)
, _outlineSize(0.0f)
, _ascender(0)
, _descender(0)
, _lineHeight(0)
, _usedGlyphs(GlyphCollection::ASCII)
{
    if (outline > 0.0f)
    {
        _outlineSize = outline * CC_CONTENT_SCALE_FACTOR();
        FT_Stroker_New(FontFreeType::getFTLibrary(), &_stroker);
        FT_Stroker_Set(_stroker,
            (int)(_outlineSize * 64),
            FT_STROKER_LINECAP_ROUND,
            FT_STROKER_LINEJOIN_ROUND,
            0);
    }
}
// clang-format on

bool FontFreeType::createFontObject(const std::string& fontName, float fontSize)
{
    FT_Face face;
    // save font name locally
    _fontName = fontName;

    if (_streamParsingEnabled)
    {
        auto fullPath = FileUtils::getInstance()->fullPathForFilename(fontName);
        if (fullPath.empty())
            return false;

        auto fs = FileUtils::getInstance()->openFileStream(fullPath, FileStream::Mode::READ).release();
        if (!fs)
        {
            return false;
        }

        std::unique_ptr<FT_StreamRec> fts(new FT_StreamRec());
        fts->read               = ft_stream_read_callback;
        fts->close              = ft_stream_close_callback;
        fts->size               = static_cast<unsigned long>(fs->size());
        fts->descriptor.pointer = fs;

        FT_Open_Args args = {0};
        args.flags        = FT_OPEN_STREAM;
        args.stream       = fts.get();

        if (FT_Open_Face(getFTLibrary(), &args, 0, &face))
            return false;

        _fontStream = std::move(fts);
    }
    else
    {
        DataRef* sharableData;
        auto it = s_cacheFontData.find(fontName);
        if (it != s_cacheFontData.end())
        {
            sharableData = &it->second;
        }
        else
        {
            sharableData            = &s_cacheFontData[fontName];
            sharableData->data           = FileUtils::getInstance()->getDataFromFile(fontName);
        }

        ++sharableData->referenceCount;
        auto& data = sharableData->data;
        if (data.isNull() || FT_New_Memory_Face(getFTLibrary(), data.getBytes(),
                                                static_cast<FT_Long>(data.getSize()), 0, &face))
            return false;
    }

    if (FT_Select_Charmap(face, FT_ENCODING_UNICODE))
    {
        int foundIndex = -1;
        for (int charmapIndex = 0; charmapIndex < face->num_charmaps; charmapIndex++)
        {
            if (face->charmaps[charmapIndex]->encoding != FT_ENCODING_NONE)
            {
                foundIndex = charmapIndex;
                break;
            }
        }

        if (foundIndex == -1)
        {
            return false;
        }

        _encoding = face->charmaps[foundIndex]->encoding;
        if (FT_Select_Charmap(face, _encoding))
        {
            return false;
        }
    }

    // set the requested font size
    int dpi            = 72;
    int fontSizePoints = (int)(64.f * fontSize * CC_CONTENT_SCALE_FACTOR());
    if (FT_Set_Char_Size(face, fontSizePoints, fontSizePoints, dpi, dpi))
        return false;

    // store the face globally
    _fontFace = face;

    // Notes:
    //  a. Since freetype 2.8.1 the TT matrics isn't sync to size_matrics, see the function 'tt_size_request' in
    //  truetype/ttdriver.c b. The TT spec always asks for ROUND, not FLOOR or CEIL, see also the function
    //  'tt_size_reset' in truetype/ttobjs.c
    // ** Please see description of FT_Size_Metrics_ in freetype.h about this solution
    auto& size_metrics = _fontFace->size->metrics;
    if (_doNativeBytecodeHinting && !strcmp(FT_Get_Font_Format(face), "TrueType"))
    {
        _ascender  = FT_PIX_ROUND(FT_MulFix(face->ascender, size_metrics.y_scale));
        _descender = FT_PIX_ROUND(FT_MulFix(face->descender, size_metrics.y_scale));
    }
    else
    {
        _ascender  = size_metrics.ascender;
        _descender = size_metrics.descender;
    }

    _lineHeight = (_ascender - _descender) >> 6;

    // done and good
    return true;
}

FontFreeType::~FontFreeType()
{
    if (_FTInitialized)
    {
        if (_stroker)
        {
            FT_Stroker_Done(_stroker);
        }
        if (_fontFace)
        {
            FT_Done_Face(_fontFace);
        }
    }

    auto iter = s_cacheFontData.find(_fontName);
    if (iter != s_cacheFontData.end())
    {
        iter->second.referenceCount -= 1;
        if (iter->second.referenceCount == 0)
        {
            s_cacheFontData.erase(iter);
        }
    }
}

FontAtlas* FontFreeType::newFontAtlas()
{
    auto fontAtlas = new (std::nothrow) FontAtlas(this);
    if (fontAtlas && _usedGlyphs != GlyphCollection::DYNAMIC)
    {
        std::u32string utf32;
        if (StringUtils::UTF8ToUTF32(getGlyphCollection(), utf32))
        {
            fontAtlas->prepareLetterDefinitions(utf32);
        }
    }
    return fontAtlas;
}

int* FontFreeType::getHorizontalKerningForTextUTF32(const std::u32string& text, int& outNumLetters) const
{
    if (!_fontFace)
        return nullptr;

    outNumLetters = static_cast<int>(text.length());

    if (!outNumLetters)
        return nullptr;

    int* sizes = new (std::nothrow) int[outNumLetters];
    if (!sizes)
        return nullptr;
    memset(sizes, 0, outNumLetters * sizeof(int));

    bool hasKerning = FT_HAS_KERNING(_fontFace) != 0;
    if (hasKerning)
    {
        for (int c = 1; c < outNumLetters; ++c)
        {
            sizes[c] = getHorizontalKerningForChars(text[c - 1], text[c]);
        }
    }

    return sizes;
}

int FontFreeType::getHorizontalKerningForChars(uint64_t firstChar, uint64_t secondChar) const
{
    // get the ID to the char we need
    int glyphIndex1 = FT_Get_Char_Index(_fontFace, static_cast<FT_ULong>(firstChar));

    if (!glyphIndex1)
        return 0;

    // get the ID to the char we need
    int glyphIndex2 = FT_Get_Char_Index(_fontFace, static_cast<FT_ULong>(secondChar));

    if (!glyphIndex2)
        return 0;

    FT_Vector kerning;

    if (FT_Get_Kerning(_fontFace, glyphIndex1, glyphIndex2, FT_KERNING_DEFAULT, &kerning))
        return 0;

    return (static_cast<int>(kerning.x >> 6));
}

int FontFreeType::getFontAscender() const
{
    return _ascender >> 6;
}

const char* FontFreeType::getFontFamily() const
{
    if (!_fontFace)
        return nullptr;

    return _fontFace->family_name;
}

unsigned char* FontFreeType::getGlyphBitmap(uint32_t theChar,
                                            int32_t& outWidth,
                                            int32_t& outHeight,
                                            Rect& outRect,
                                            int& xAdvance)
{
    unsigned char* ret = nullptr;

    do
    {
        if (_fontFace == nullptr)
            break;

        // @remark: glyphIndex=0 means charactor is mssing on current font face
        auto glyphIndex = FT_Get_Char_Index(_fontFace, static_cast<FT_ULong>(theChar));
        if (FT_Load_Glyph(_fontFace, glyphIndex, FT_LOAD_RENDER | FT_LOAD_NO_AUTOHINT))
            break;

#if defined(COCOS2D_DEBUG) && COCOS2D_DEBUG > 0
        if (glyphIndex == 0)
        {
            std::u32string charUTF32(1, theChar);
            std::string charUTF8;
            cocos2d::StringUtils::UTF32ToUTF8(charUTF32, charUTF8);

            if (charUTF8 == "\n")
                charUTF8 = "\\n";
            cocos2d::log("The font face: %s doesn't contains char: <%s>", _fontFace->charmap->face->family_name,
                         charUTF8.c_str());
        }
#endif
        if (_distanceFieldEnabled && _fontFace->glyph->bitmap.buffer)
        {
            // Require freetype version > 2.11.0, because freetype 2.11.0 sdf has memory access bug, see: https://gitlab.freedesktop.org/freetype/freetype/-/issues/1077
            FT_Render_Glyph(_fontFace->glyph, FT_Render_Mode::FT_RENDER_MODE_SDF);
        }

        auto& metrics       = _fontFace->glyph->metrics;
        outRect.origin.x    = static_cast<float>(metrics.horiBearingX >> 6);
        outRect.origin.y    = static_cast<float>(-(metrics.horiBearingY >> 6));
        outRect.size.width  = static_cast<float>((metrics.width >> 6));
        outRect.size.height = static_cast<float>((metrics.height >> 6));

        xAdvance = (static_cast<int>(_fontFace->glyph->metrics.horiAdvance >> 6));

        outWidth  = _fontFace->glyph->bitmap.width;
        outHeight = _fontFace->glyph->bitmap.rows;
        ret       = _fontFace->glyph->bitmap.buffer;

        if (_outlineSize > 0 && outWidth > 0 && outHeight > 0)
        {
            auto copyBitmap = new (std::nothrow) unsigned char[outWidth * outHeight];
            memcpy(copyBitmap, ret, outWidth * outHeight * sizeof(unsigned char));

            FT_BBox bbox;
            auto outlineBitmap = getGlyphBitmapWithOutline(glyphIndex, bbox);
            if (outlineBitmap == nullptr)
            {
                ret = nullptr;
                delete[] copyBitmap;
                break;
            }

            int glyphMinX = (int)outRect.origin.x;
            int glyphMaxX = (int)(outRect.origin.x + outWidth);
            int glyphMinY = (int)(-outHeight - outRect.origin.y);
            int glyphMaxY = (int)-outRect.origin.y;

            auto outlineMinX   = bbox.xMin >> 6;
            auto outlineMaxX   = bbox.xMax >> 6;
            auto outlineMinY   = bbox.yMin >> 6;
            auto outlineMaxY   = bbox.yMax >> 6;
            auto outlineWidth  = outlineMaxX - outlineMinX;
            auto outlineHeight = outlineMaxY - outlineMinY;

            auto blendImageMinX = MIN(outlineMinX, glyphMinX);
            auto blendImageMaxY = MAX(outlineMaxY, glyphMaxY);
            auto blendWidth     = MAX(outlineMaxX, glyphMaxX) - blendImageMinX;
            auto blendHeight    = blendImageMaxY - MIN(outlineMinY, glyphMinY);

            outRect.origin.x = (float)blendImageMinX;
            outRect.origin.y = -blendImageMaxY + _outlineSize;

            unsigned char* blendImage = nullptr;
            if (blendWidth > 0 && blendHeight > 0)
            {
                FT_Pos index, index2;
                auto imageSize = blendWidth * blendHeight * 2;
                blendImage     = new (std::nothrow) unsigned char[imageSize];
                memset(blendImage, 0, imageSize);

                auto px = outlineMinX - blendImageMinX;
                auto py = blendImageMaxY - outlineMaxY;
                for (int x = 0; x < outlineWidth; ++x)
                {
                    for (int y = 0; y < outlineHeight; ++y)
                    {
                        index                 = px + x + ((py + y) * blendWidth);
                        index2                = x + (y * outlineWidth);
                        blendImage[2 * index] = outlineBitmap[index2];
                    }
                }

                px = glyphMinX - blendImageMinX;
                py = blendImageMaxY - glyphMaxY;
                for (int x = 0; x < outWidth; ++x)
                {
                    for (int y = 0; y < outHeight; ++y)
                    {
                        index                     = px + x + ((y + py) * blendWidth);
                        index2                    = x + (y * outWidth);
                        blendImage[2 * index + 1] = copyBitmap[index2];
                    }
                }
            }

            outRect.size.width  = (float)blendWidth;
            outRect.size.height = (float)blendHeight;
            outWidth            = blendWidth;
            outHeight           = blendHeight;

            delete[] outlineBitmap;
            delete[] copyBitmap;
            ret = blendImage;
        }

        return ret;
    } while (0);

    outRect.size.width  = 0;
    outRect.size.height = 0;
    xAdvance            = 0;

    return nullptr;
}

unsigned char* FontFreeType::getGlyphBitmapWithOutline(unsigned int glyphIndex, FT_BBox& bbox)
{
    unsigned char* ret = nullptr;
    if (FT_Load_Glyph(_fontFace, glyphIndex, FT_LOAD_NO_BITMAP) == 0)
    {
        if (_fontFace->glyph->format == FT_GLYPH_FORMAT_OUTLINE)
        {
            FT_Glyph glyph;
            if (FT_Get_Glyph(_fontFace->glyph, &glyph) == 0)
            {
                FT_Glyph_StrokeBorder(&glyph, _stroker, 0, 1);
                if (glyph->format == FT_GLYPH_FORMAT_OUTLINE)
                {
                    FT_Outline* outline = &reinterpret_cast<FT_OutlineGlyph>(glyph)->outline;
                    FT_Glyph_Get_CBox(glyph, FT_GLYPH_BBOX_GRIDFIT, &bbox);
                    int32_t width = (bbox.xMax - bbox.xMin) >> 6;
                    int32_t rows  = (bbox.yMax - bbox.yMin) >> 6;

                    FT_Bitmap bmp;
                    bmp.buffer = new (std::nothrow) unsigned char[width * rows];
                    memset(bmp.buffer, 0, width * rows);
                    bmp.width      = (int)width;
                    bmp.rows       = (int)rows;
                    bmp.pitch      = (int)width;
                    bmp.pixel_mode = FT_PIXEL_MODE_GRAY;
                    bmp.num_grays  = 256;

                    FT_Raster_Params params;
                    memset(&params, 0, sizeof(params));
                    params.source = outline;
                    params.target = &bmp;
                    params.flags  = FT_RASTER_FLAG_AA;
                    FT_Outline_Translate(outline, -bbox.xMin, -bbox.yMin);
                    FT_Outline_Render(_FTlibrary, outline, &params);

                    ret = bmp.buffer;
                }
                FT_Done_Glyph(glyph);
            }
        }
    }

    return ret;
}

void FontFreeType::renderCharAt(unsigned char* dest,
                                int posX,
                                int posY,
                                unsigned char* bitmap,
                                int32_t bitmapWidth,
                                int32_t bitmapHeight)
{
    int iX = posX;
    int iY = posY;

    if (_outlineSize > 0)
    {
        unsigned char tempChar;
        for (int32_t y = 0; y < bitmapHeight; ++y)
        {
            int32_t bitmap_y = y * bitmapWidth;

            for (int x = 0; x < bitmapWidth; ++x)
            {
                tempChar                                                 = bitmap[(bitmap_y + x) * 2];
                dest[(iX + (iY * FontAtlas::CacheTextureWidth)) * 2]     = tempChar;
                tempChar                                                 = bitmap[(bitmap_y + x) * 2 + 1];
                dest[(iX + (iY * FontAtlas::CacheTextureWidth)) * 2 + 1] = tempChar;

                iX += 1;
            }

            iX = posX;
            iY += 1;
        }
        delete[] bitmap;
    }
    else
    {
        for (int32_t y = 0; y < bitmapHeight; ++y)
        {
            int32_t bitmap_y = y * bitmapWidth;

            for (int x = 0; x < bitmapWidth; ++x)
            {
                unsigned char cTemp = bitmap[bitmap_y + x];

                // the final pixel
                dest[(iX + (iY * FontAtlas::CacheTextureWidth))] = cTemp;

                iX += 1;
            }

            iX = posX;
            iY += 1;
        }
    }
}

void FontFreeType::setGlyphCollection(GlyphCollection glyphs, const char* customGlyphs /* = nullptr */)
{
    _usedGlyphs = glyphs;
    if (glyphs == GlyphCollection::CUSTOM)
    {
        _customGlyphs = customGlyphs;
    }
}

const char* FontFreeType::getGlyphCollection() const
{
    const char* glyphCollection = nullptr;
    switch (_usedGlyphs)
    {
        case cocos2d::GlyphCollection::DYNAMIC:
            break;
        case cocos2d::GlyphCollection::NEHE:
            glyphCollection = _glyphNEHE;
            break;
        case cocos2d::GlyphCollection::ASCII:
            glyphCollection = _glyphASCII;
            break;
        case cocos2d::GlyphCollection::CUSTOM:
            glyphCollection = _customGlyphs.c_str();
            break;
        default:
            break;
    }

    return glyphCollection;
}

void FontFreeType::releaseFont(const std::string& fontName)
{
    auto item = s_cacheFontData.begin();
    while (s_cacheFontData.end() != item)
    {
        if (item->first.find(fontName) != std::string::npos)
            item = s_cacheFontData.erase(item);
        else
            item++;
    }
}

NS_CC_END