C++ SkPaint::getHinting方法代码示例

sk_sp<SkFont> SkFont::Testing_CreateFromPaint(const SkPaint& paint) {
    uint32_t flags = 0;
    if (paint.isVerticalText()) {
        flags |= kVertical_Flag;
    }
    if (paint.isEmbeddedBitmapText()) {
        flags |= kEmbeddedBitmaps_Flag;
    }
    if (paint.getFlags() & SkPaint::kGenA8FromLCD_Flag) {
        flags |= kGenA8FromLCD_Flag;
    }
    if (paint.isFakeBoldText()) {
        flags |= kEmbolden_Flag;
    }

    if (SkPaint::kFull_Hinting == paint.getHinting()) {
        flags |= kEnableByteCodeHints_Flag;
    }
    if (paint.isAutohinted()) {
        flags |= kEnableAutoHints_Flag;
    }
    if (paint.isSubpixelText() || paint.isLinearText()) {
        // this is our default
    } else {
        flags |= kUseNonlinearMetrics_Flag;
    }

    MaskType maskType = SkFont::kBW_MaskType;
    if (paint.isAntiAlias()) {
        maskType = paint.isLCDRenderText() ? kLCD_MaskType : kA8_MaskType;
    }

    return Make(sk_ref_sp(paint.getTypeface()), paint.getTextSize(), paint.getTextScaleX(),
                paint.getTextSkewX(), maskType, flags);
}

bool SkBitmapDevice::filterTextFlags(const SkPaint& paint, TextFlags* flags) {
    if (!paint.isLCDRenderText() || !paint.isAntiAlias()) {
        // we're cool with the paint as is
        return false;
    }

    if (kN32_SkColorType != fBitmap.colorType() ||
        paint.getRasterizer() ||
        paint.getPathEffect() ||
        paint.isFakeBoldText() ||
        paint.getStyle() != SkPaint::kFill_Style ||
        !SkXfermode::IsMode(paint.getXfermode(), SkXfermode::kSrcOver_Mode)) {
        // turn off lcd
        flags->fFlags = paint.getFlags() & ~SkPaint::kLCDRenderText_Flag;
        flags->fHinting = paint.getHinting();
        return true;
    }
    // we're cool with the paint as is
    return false;
}

PassRefPtr<JSONObject> LoggingCanvas::objectForSkPaint(const SkPaint& paint)
{
    RefPtr<JSONObject> paintItem = JSONObject::create();
    paintItem->setNumber("textSize", paint.getTextSize());
    paintItem->setNumber("textScaleX", paint.getTextScaleX());
    paintItem->setNumber("textSkewX", paint.getTextSkewX());
    if (SkShader* shader = paint.getShader())
        paintItem->setObject("shader", objectForSkShader(*shader));
    paintItem->setString("color", stringForSkColor(paint.getColor()));
    paintItem->setNumber("strokeWidth", paint.getStrokeWidth());
    paintItem->setNumber("strokeMiter", paint.getStrokeMiter());
    paintItem->setString("flags", stringForSkPaintFlags(paint));
    paintItem->setString("filterLevel", filterQualityName(paint.getFilterQuality()));
    paintItem->setString("textAlign", textAlignName(paint.getTextAlign()));
    paintItem->setString("strokeCap", strokeCapName(paint.getStrokeCap()));
    paintItem->setString("strokeJoin", strokeJoinName(paint.getStrokeJoin()));
    paintItem->setString("styleName", styleName(paint.getStyle()));
    paintItem->setString("textEncoding", textEncodingName(paint.getTextEncoding()));
    paintItem->setString("hinting", hintingName(paint.getHinting()));
    return paintItem.release();
}

bool SkDevice::filterTextFlags(const SkPaint& paint, TextFlags* flags) {
    if (!paint.isLCDRenderText()) {
        // we're cool with the paint as is
        return false;
    }

    if (SkBitmap::kARGB_8888_Config != fBitmap.config() ||
        paint.getShader() ||
        paint.getXfermode() || // unless its srcover
        paint.getMaskFilter() ||
        paint.getRasterizer() ||
        paint.getColorFilter() ||
        paint.getPathEffect() ||
        paint.isFakeBoldText() ||
        paint.getStyle() != SkPaint::kFill_Style) {
        // turn off lcd
        flags->fFlags = paint.getFlags() & ~SkPaint::kLCDRenderText_Flag;
        flags->fHinting = paint.getHinting();
        return true;
    }
    // we're cool with the paint as is
    return false;
}

/*
 *  Header:
 *      paint flags     : 32
 *      non_def bits    : 16
 *      xfermode enum   : 8
 *      pad zeros       : 8
 */
static void write_paint(SkWriteBuffer& writer, const SkPaint& paint, unsigned usage) {
    uint32_t packedFlags = pack_paint_flags(paint.getFlags(), paint.getHinting(),
                                            paint.getTextAlign(), paint.getFilterQuality(),
                                            paint.getStyle(), paint.getStrokeCap(),
                                            paint.getStrokeJoin(), paint.getTextEncoding());
    writer.write32(packedFlags);

    unsigned nondef = compute_nondef(paint, (PaintUsage)usage);
    const uint8_t pad = 0;
    writer.write32((nondef << 16) | ((unsigned)paint.getBlendMode() << 8) | pad);

    CHECK_WRITE_SCALAR(writer, nondef, paint, TextSize);
    CHECK_WRITE_SCALAR(writer, nondef, paint, TextScaleX);
    CHECK_WRITE_SCALAR(writer, nondef, paint, TextSkewX);
    CHECK_WRITE_SCALAR(writer, nondef, paint, StrokeWidth);
    CHECK_WRITE_SCALAR(writer, nondef, paint, StrokeMiter);

    if (nondef & kColor_NonDef) {
        writer.write32(paint.getColor());
    }
    if (nondef & kTypeface_NonDef) {
        // TODO: explore idea of writing bits indicating "use the prev (or prev N) face"
        // e.g. 1-N bits is an index into a ring buffer of typefaces
        SkTypeface* tf = paint.getTypeface();
        SkASSERT(tf);
        writer.writeTypeface(tf);
    }

    CHECK_WRITE_FLATTENABLE(writer, nondef, paint, PathEffect);
    CHECK_WRITE_FLATTENABLE(writer, nondef, paint, Shader);
    CHECK_WRITE_FLATTENABLE(writer, nondef, paint, MaskFilter);
    CHECK_WRITE_FLATTENABLE(writer, nondef, paint, ColorFilter);
    CHECK_WRITE_FLATTENABLE(writer, nondef, paint, Rasterizer);
    CHECK_WRITE_FLATTENABLE(writer, nondef, paint, ImageFilter);
    CHECK_WRITE_FLATTENABLE(writer, nondef, paint, DrawLooper);
}

void SimpleFontData::platformInit() {
  if (!m_platformData.size()) {
    m_fontMetrics.reset();
    m_avgCharWidth = 0;
    m_maxCharWidth = 0;
    return;
  }

  SkPaint paint;
  SkPaint::FontMetrics metrics;

  m_platformData.setupPaint(&paint);
  paint.getFontMetrics(&metrics);
  SkTypeface* face = paint.getTypeface();
  ASSERT(face);

  int vdmxAscent = 0, vdmxDescent = 0;
  bool isVDMXValid = false;

#if OS(LINUX) || OS(ANDROID)
  // Manually digging up VDMX metrics is only applicable when bytecode hinting
  // using FreeType. With GDI, the metrics will already have taken this into
  // account (as needed). With DirectWrite or CoreText, no bytecode hinting is
  // ever done. This code should be pushed into FreeType (hinted font metrics).
  static const uint32_t vdmxTag = SkSetFourByteTag('V', 'D', 'M', 'X');
  int pixelSize = m_platformData.size() + 0.5;
  if (!paint.isAutohinted() &&
      (paint.getHinting() == SkPaint::kFull_Hinting ||
       paint.getHinting() == SkPaint::kNormal_Hinting)) {
    size_t vdmxSize = face->getTableSize(vdmxTag);
    if (vdmxSize && vdmxSize < maxVDMXTableSize) {
      uint8_t* vdmxTable = (uint8_t*)fastMalloc(vdmxSize);
      if (vdmxTable &&
          face->getTableData(vdmxTag, 0, vdmxSize, vdmxTable) == vdmxSize &&
          parseVDMX(&vdmxAscent, &vdmxDescent, vdmxTable, vdmxSize, pixelSize))
        isVDMXValid = true;
      fastFree(vdmxTable);
    }
  }
#endif

  float ascent;
  float descent;

  // Beware those who step here: This code is designed to match Win32 font
  // metrics *exactly* (except the adjustment of ascent/descent on
  // Linux/Android).
  if (isVDMXValid) {
    ascent = vdmxAscent;
    descent = -vdmxDescent;
  } else {
    ascent = SkScalarRoundToInt(-metrics.fAscent);
    descent = SkScalarRoundToInt(metrics.fDescent);
#if OS(LINUX) || OS(ANDROID)
    // When subpixel positioning is enabled, if the descent is rounded down, the
    // descent part of the glyph may be truncated when displayed in a 'overflow:
    // hidden' container. To avoid that, borrow 1 unit from the ascent when
    // possible.
    // FIXME: This can be removed if sub-pixel ascent/descent is supported.
    if (platformData().fontRenderStyle().useSubpixelPositioning &&
        descent < SkScalarToFloat(metrics.fDescent) && ascent >= 1) {
      ++descent;
      --ascent;
    }
#endif
  }

  m_fontMetrics.setAscent(ascent);
  m_fontMetrics.setDescent(descent);

  float xHeight;
  if (metrics.fXHeight) {
    xHeight = metrics.fXHeight;
    m_fontMetrics.setXHeight(xHeight);
  } else {
    xHeight = ascent * 0.56;  // Best guess from Windows font metrics.
    m_fontMetrics.setXHeight(xHeight);
    m_fontMetrics.setHasXHeight(false);
  }

  float lineGap = SkScalarToFloat(metrics.fLeading);
  m_fontMetrics.setLineGap(lineGap);
  m_fontMetrics.setLineSpacing(lroundf(ascent) + lroundf(descent) +
                               lroundf(lineGap));

  SkScalar underlineThickness, underlinePosition;
  if (metrics.hasUnderlineThickness(&underlineThickness) &&
      metrics.hasUnderlinePosition(&underlinePosition)) {
    m_fontMetrics.setUnderlineThickness(SkScalarToFloat(underlineThickness));
    m_fontMetrics.setUnderlinePosition(SkScalarToFloat(-underlinePosition));
  }

  if (platformData().orientation() == Vertical &&
      !isTextOrientationFallback()) {
    static const uint32_t vheaTag = SkSetFourByteTag('v', 'h', 'e', 'a');
    static const uint32_t vorgTag = SkSetFourByteTag('V', 'O', 'R', 'G');
    size_t vheaSize = face->getTableSize(vheaTag);
    size_t vorgSize = face->getTableSize(vorgTag);
    if ((vheaSize > 0) || (vorgSize > 0))
      m_hasVerticalGlyphs = true;
//.........这里部分代码省略.........

// Even with kEntirePaint_Bits, we always ensure that the master paint's
// text-encoding is respected, since that controls how we interpret the
// text/length parameters of a draw[Pos]Text call.
void SkLayerDrawLooper::ApplyInfo(SkPaint* dst, const SkPaint& src,
                                  const LayerInfo& info) {

    uint32_t mask = info.fFlagsMask;
    dst->setFlags((dst->getFlags() & ~mask) | (src.getFlags() & mask));
    dst->setColor(xferColor(src.getColor(), dst->getColor(), info.fColorMode));

    BitFlags bits = info.fPaintBits;
    SkPaint::TextEncoding encoding = dst->getTextEncoding();

    if (0 == bits) {
        return;
    }
    if (kEntirePaint_Bits == bits) {
        // we've already computed these, so save it from the assignment
        uint32_t f = dst->getFlags();
        SkColor c = dst->getColor();
        *dst = src;
        dst->setFlags(f);
        dst->setColor(c);
        dst->setTextEncoding(encoding);
        return;
    }

    if (bits & kStyle_Bit) {
        dst->setStyle(src.getStyle());
        dst->setStrokeWidth(src.getStrokeWidth());
        dst->setStrokeMiter(src.getStrokeMiter());
        dst->setStrokeCap(src.getStrokeCap());
        dst->setStrokeJoin(src.getStrokeJoin());
    }

    if (bits & kTextSkewX_Bit) {
        dst->setTextSkewX(src.getTextSkewX());
    }

    if (bits & kPathEffect_Bit) {
        dst->setPathEffect(src.getPathEffect());
    }
    if (bits & kMaskFilter_Bit) {
        dst->setMaskFilter(src.getMaskFilter());
    }
    if (bits & kShader_Bit) {
        dst->setShader(src.getShader());
    }
    if (bits & kColorFilter_Bit) {
        dst->setColorFilter(src.getColorFilter());
    }
    if (bits & kXfermode_Bit) {
        dst->setXfermode(src.getXfermode());
    }

    // we don't override these
#if 0
    dst->setTypeface(src.getTypeface());
    dst->setTextSize(src.getTextSize());
    dst->setTextScaleX(src.getTextScaleX());
    dst->setRasterizer(src.getRasterizer());
    dst->setLooper(src.getLooper());
    dst->setTextEncoding(src.getTextEncoding());
    dst->setHinting(src.getHinting());
#endif
}

static bool is_enable_bytecode_hints(const SkPaint& paint) {
    return paint.getHinting() >= SkPaint::kFull_Hinting;
}

// Even with kEntirePaint_Bits, we always ensure that the master paint's
// text-encoding is respected, since that controls how we interpret the
// text/length parameters of a draw[Pos]Text call.
void SkLayerDrawLooper::LayerDrawLooperContext::ApplyInfo(
        SkPaint* dst, const SkPaint& src, const LayerInfo& info) {
    SkColor4f srcColor = src.getColor4f();
#ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
    // The framework may respect the alpha value on the original paint.
    // Match this legacy behavior.
    if (src.getAlpha() == 255) {
        srcColor.fA = dst->getColor4f().fA;
    }
#endif
    dst->setColor4f(xferColor(srcColor, dst->getColor4f(), (SkBlendMode)info.fColorMode),
                    sk_srgb_singleton());

    BitFlags bits = info.fPaintBits;
    SkPaint::TextEncoding encoding = dst->getTextEncoding();

    if (0 == bits) {
        return;
    }
    if (kEntirePaint_Bits == bits) {
        // we've already computed these, so save it from the assignment
        uint32_t f = dst->getFlags();
        SkColor4f c = dst->getColor4f();
        *dst = src;
        dst->setFlags(f);
        dst->setColor4f(c, sk_srgb_singleton());
        dst->setTextEncoding(encoding);
        return;
    }

    if (bits & kStyle_Bit) {
        dst->setStyle(src.getStyle());
        dst->setStrokeWidth(src.getStrokeWidth());
        dst->setStrokeMiter(src.getStrokeMiter());
        dst->setStrokeCap(src.getStrokeCap());
        dst->setStrokeJoin(src.getStrokeJoin());
    }

    if (bits & kTextSkewX_Bit) {
        dst->setTextSkewX(src.getTextSkewX());
    }

    if (bits & kPathEffect_Bit) {
        dst->setPathEffect(src.refPathEffect());
    }
    if (bits & kMaskFilter_Bit) {
        dst->setMaskFilter(src.refMaskFilter());
    }
    if (bits & kShader_Bit) {
        dst->setShader(src.refShader());
    }
    if (bits & kColorFilter_Bit) {
        dst->setColorFilter(src.refColorFilter());
    }
    if (bits & kXfermode_Bit) {
        dst->setBlendMode(src.getBlendMode());
    }

    // we don't override these
#if 0
    dst->setTypeface(src.getTypeface());
    dst->setTextSize(src.getTextSize());
    dst->setTextScaleX(src.getTextScaleX());
    dst->setRasterizer(src.getRasterizer());
    dst->setLooper(src.getLooper());
    dst->setTextEncoding(src.getTextEncoding());
    dst->setHinting(src.getHinting());
#endif
}