qfontengine_ft.cpp

奇趣公司比较新的qt/emd版本

            } else {
                while (h--) {
                    for (int x = 0; x < info.width; x++) {
                        uint blue = src[x];
                        uint green = src[x+bitmap.pitch];
                        uint red = src[x+2*bitmap.pitch];
                        uint high = (red*subpixel_filter[0][0] + green*subpixel_filter[0][1] + blue*subpixel_filter[0][2]) >> 8;
                        uint mid = (red*subpixel_filter[1][0] + green*subpixel_filter[1][1] + blue*subpixel_filter[1][2]) >> 8;
                        uint low = (red*subpixel_filter[2][0] + green*subpixel_filter[2][1] + blue*subpixel_filter[2][2]) >> 8;
                        uint res = (mid << 24) + (high << 16) + (mid << 8) + low;
                        dst[x] = res;
                    }
                    dst += info.width;
                    src += 3*bitmap.pitch;
                }
            }
            delete [] bitmap.buffer;
        }
    } else if (slot->format == FT_GLYPH_FORMAT_BITMAP) {
        Q_ASSERT(slot->bitmap.pixel_mode == FT_PIXEL_MODE_MONO);
        uchar *src = slot->bitmap.buffer;
        uchar *dst = glyph_buffer;
        int h = slot->bitmap.rows;
        if (format == Format_Mono) {
            int bytes = ((info.width + 7) & ~7) >> 3;
            while (h--) {
                memcpy (dst, src, bytes);
                dst += pitch;
                src += slot->bitmap.pitch;
            }
        } else {
            if (hsubpixel) {
                while (h--) {
                    uint *dd = (uint *)dst;
                    *dd++ = 0;
                    for (int x = 0; x < slot->bitmap.width; x++) {
                        uint a = ((src[x >> 3] & (0x80 >> (x & 7))) ? 0xffffff : 0x000000);
                        *dd++ = a;
                    }
                    *dd++ = 0;
                    dst += pitch;
                    src += slot->bitmap.pitch;
                }
            } else if (vfactor != 1) {
                while (h--) {
                    uint *dd = (uint *)dst;
                    for (int x = 0; x < slot->bitmap.width; x++) {
                        uint a = ((src[x >> 3] & (0x80 >> (x & 7))) ? 0xffffff : 0x000000);
                        *dd++ = a;
                    }
                    dst += pitch;
                    src += slot->bitmap.pitch;
                }
            } else {
                while (h--) {
                    for (int x = 0; x < slot->bitmap.width; x++) {
                        unsigned char a = ((src[x >> 3] & (0x80 >> (x & 7))) ? 0xff : 0x00);
                        dst[x] = a;
                    }
                    dst += pitch;
                    src += slot->bitmap.pitch;
                }
            }
        }
    } else {
        qWarning("QFontEngine: Glyph neither outline nor bitmap format=%d", slot->format);
        delete [] glyph_buffer;
        return 0;
    }

    bool large_glyph = (((signed char)(slot->linearHoriAdvance>>16) != slot->linearHoriAdvance>>16)
                        || ((uchar)(info.width) != info.width)
                        || ((uchar)(info.height) != info.height)
                        || ((signed char)(info.x) != info.x)
                        || ((signed char)(info.y) != info.y)
                        || ((signed char)(info.xOff) != info.xOff));

    if (large_glyph) {
//         qDebug("got a large glyph!");
        delete [] glyph_buffer;
        return 0;
    }

    if (!g) {
        g = new Glyph;
        g->uploadedToServer = false;
        g->data = 0;
    }

    g->linearAdvance = slot->linearHoriAdvance >> 10;
    g->width = info.width;
    g->height = TRUNC(top - bottom);
    g->x = -info.x;
    g->y = TRUNC(top);
    g->advance = TRUNC(ROUND(slot->advance.x));
    g->format = format;
    delete [] g->data;
    g->data = glyph_buffer;

    if (uploadToServer) {
        uploadGlyphToServer(set, glyph, g, &info, size);
    }

    set->glyph_data[glyph] = g;

    return g;
}

bool QFontEngineFT::uploadGlyphToServer(QGlyphSet *set, uint glyphid, Glyph *g, GlyphInfo *info, int glyphDataSize) const
{
    Q_UNUSED(set);
    Q_UNUSED(glyphid);
    Q_UNUSED(g);
    Q_UNUSED(info);
    Q_UNUSED(glyphDataSize);
    return false;
}

QFontEngine::FaceId QFontEngineFT::faceId() const
{
    return face_id;
}

QFontEngine::Properties QFontEngineFT::properties() const
{
    Properties p = freetype->properties();
    if (p.postscriptName.isEmpty()) {
        p.postscriptName = fontDef.family.toUtf8();
#ifndef QT_NO_PRINTER
        p.postscriptName = QPdf::stripSpecialCharacters(p.postscriptName);
#endif
    }

    return freetype->properties();
}

QByteArray QFontEngineFT::getSfntTable(uint tag) const
{
    return freetype->getSfntTable(tag);
}

int QFontEngineFT::synthesized() const
{
    int s = 0;
    if ((fontDef.style != QFont::StyleNormal) && !(freetype->face->style_flags & FT_STYLE_FLAG_ITALIC))
        s = SynthesizedItalic;
    if (fontDef.stretch != 100 && FT_IS_SCALABLE(freetype->face))
        s |= SynthesizedStretch;
    return s;
}

QFixed QFontEngineFT::ascent() const
{
    return QFixed::fromFixed(metrics.ascender);
}

QFixed QFontEngineFT::descent() const
{
    return QFixed::fromFixed(-metrics.descender + (1<<6));
}

QFixed QFontEngineFT::leading() const
{
    return QFixed::fromFixed(metrics.height - metrics.ascender + metrics.descender);
}

QFixed QFontEngineFT::xHeight() const
{
    TT_OS2 *os2 = (TT_OS2 *)FT_Get_Sfnt_Table(freetype->face, ft_sfnt_os2);
    if (os2 && os2->sxHeight)
        return QFixed(os2->sxHeight*freetype->face->size->metrics.y_ppem)/freetype->face->units_per_EM;
    return QFontEngine::xHeight();
}

QFixed QFontEngineFT::averageCharWidth() const
{
    TT_OS2 *os2 = (TT_OS2 *)FT_Get_Sfnt_Table(freetype->face, ft_sfnt_os2);
    if (os2 && os2->xAvgCharWidth)
        return QFixed(os2->xAvgCharWidth*freetype->face->size->metrics.y_ppem)/freetype->face->units_per_EM;
    return QFontEngine::averageCharWidth();
}

qreal QFontEngineFT::maxCharWidth() const
{
    return metrics.max_advance >> 6;
}

static const ushort char_table[] = {
        40,
        67,
        70,
        75,
        86,
        88,
        89,
        91,
        102,
        114,
        124,
        127,
        205,
        645,
        884,
        922,
        1070,
        12386
};

static const int char_table_entries = sizeof(char_table)/sizeof(ushort);


qreal QFontEngineFT::minLeftBearing() const
{
    if (lbearing == SHRT_MIN)
        (void) minRightBearing(); // calculates both
    return lbearing.toReal();
}

qreal QFontEngineFT::minRightBearing() const
{
    if (rbearing == SHRT_MIN) {
        lbearing = rbearing = 0;
        const QChar *ch = (const QChar *)(const void*)char_table;
        QGlyphLayout glyphs[char_table_entries];
        int ng = char_table_entries;
        stringToCMap(ch, char_table_entries, glyphs, &ng, QTextEngine::GlyphIndicesOnly);
        while (--ng) {
            if (glyphs[ng].glyph) {
                glyph_metrics_t gi = const_cast<QFontEngineFT *>(this)->boundingBox(glyphs[ng].glyph);
                lbearing = qMin(lbearing, gi.x);
                rbearing = qMin(rbearing, (gi.xoff - gi.x - gi.width));
            }
        }
    }
    return rbearing.toReal();
}

QFixed QFontEngineFT::lineThickness() const
{
    return line_thickness;
}

QFixed QFontEngineFT::underlinePosition() const
{
    return underline_position;
}

void QFontEngineFT::doKerning(int num_glyphs, QGlyphLayout *g, QTextEngine::ShaperFlags flags) const
{
    if (!kerning_pairs_loaded) {
        kerning_pairs_loaded = true;
        if (freetype->face->size->metrics.x_ppem != 0) {
            lockFace();
            QFixed scalingFactor(freetype->face->units_per_EM/freetype->face->size->metrics.x_ppem);
            unlockFace();
            const_cast<QFontEngineFT *>(this)->loadKerningPairs(scalingFactor);
        }
    }
    QFontEngine::doKerning(num_glyphs, g, flags);
}

QOpenType *QFontEngineFT::openType() const
{
#ifndef QT_NO_OPENTYPE
    if (_openType)
         return _openType;

    FT_Face face = lockFace();
    if (!face || !FT_IS_SFNT(face)) {
        unlockFace();
        return 0;
    }

    _openType = new QOpenType(const_cast<QFontEngineFT *>(this), face);
    unlockFace();
#endif
    return _openType;
}

QFontEngineFT::QGlyphSet *QFontEngineFT::loadTransformedGlyphSet(glyph_t *glyphs, int num_glyphs, const QTransform &matrix,
                                                                 GlyphFormat format)
{
    // FT_Set_Transform only supports scalable fonts
    if (!FT_IS_SCALABLE(freetype->face))
        return 0;

    // don't try to load huge fonts
    if (fontDef.pixelSize * qSqrt(matrix.det()) >= 64)
        return 0;

    FT_Matrix m;
    m.xx = FT_Fixed(matrix.m11() * 65536);
    m.xy = FT_Fixed(-matrix.m21() * 65536);
    m.yx = FT_Fixed(-matrix.m12() * 65536);
    m.yy = FT_Fixed(matrix.m22() * 65536);

    QGlyphSet *gs = 0;

    for (int i = 0; i < transformedGlyphSets.count(); ++i) {
        const QGlyphSet &g = transformedGlyphSets.at(i);
        if (g.transformationMatrix.xx == m.xx
            && g.transformationMatrix.xy == m.xy
            && g.transformationMatrix.yx == m.yx
            && g.transformationMatrix.yy == m.yy) {

            // found a match, move it to the front
            transformedGlyphSets.move(i, 0);
            gs = &transformedGlyphSets[0];
            break;
        }
    }

    if (!gs) {
        // don't cache more than 10 transformations
        if (transformedGlyphSets.count() >= 10) {
            transformedGlyphSets.move(transformedGlyphSets.size() - 1, 0);
            freeServerGlyphSet(transformedGlyphSets.at(0).id);
        } else {
            transformedGlyphSets.prepend(QGlyphSet());
        }
        gs = &transformedGlyphSets[0];

        qDeleteAll(gs->glyph_data);
        gs->glyph_data.clear();

        gs->id = allocateServerGlyphSet();

        gs->transformationMatrix = m;
    }

    FT_Face face = 0;
    bool lockedFace = false;

    for (int i = 0; i < num_glyphs; ++i) {
        if (!gs->glyph_data.contains(glyphs[i])) {
            if (!lockedFace) {
                face = lockFace();
                m = this->matrix;
                FT_Matrix_Multiply(&gs->transformationMatrix, &m);
                FT_Set_Transform(face, &m, 0);
                freetype->matrix = m;
                lockedFace = true;
            }
            if (!loadGlyph(gs, glyphs[i], format)) {
                FT_Set_Transform(face, &freetype->matrix, 0);
                unlockFace();
                return 0;
            }
        }
    }

    if (lockedFace) {
        FT_Set_Transform(face, &freetype->matrix, 0);
        unlockFace();
    }

    return gs;
}

void QFontEngineFT::getUnscaledGlyph(glyph_t glyph, QPainterPath *path, glyph_metrics_t *metrics)
{
    FT_Face face = lockFace(Unscaled);
    FT_Set_Transform(face, 0, 0);
    FT_Load_Glyph(face, glyph, FT_LOAD_NO_BITMAP);

    int left  = face->glyph->metrics.horiBearingX;
    int right = face->glyph->metrics.horiBearingX + face->glyph->metrics.width;
    int top    = face->glyph->metrics.horiBearingY;
    int bottom = face->glyph->metrics.horiBearingY - face->glyph->metrics.height;

    QFixedPoint p;
    p.x = 0;
    p.y = 0;

    metrics->width = QFixed::fromFixed(right-left);
    metrics->height = QFixed::fromFixed(top-bottom);
    metrics->x = QFixed::fromFixed(left);
    metrics->y = QFixed::fromFixed(-top);
    metrics->xoff = QFixed::fromFixed(face->glyph->advance.x);

    if (!FT_IS_SCALABLE(freetype->face))