C++ SkMatrix::getScaleY方法代码示例

// Check to see that the size of the bitmap that would be produced by
// scaling by the given inverted matrix is less than the maximum allowed.
static inline bool cache_size_okay(const SkBitmapProvider& provider, const SkMatrix& invMat) {
    size_t maximumAllocation = SkResourceCache::GetEffectiveSingleAllocationByteLimit();
    if (0 == maximumAllocation) {
        return true;
    }
    // float matrixScaleFactor = 1.0 / (invMat.scaleX * invMat.scaleY);
    // return ((origBitmapSize * matrixScaleFactor) < maximumAllocationSize);
    // Skip the division step:
    const size_t size = provider.info().getSafeSize(provider.info().minRowBytes());
    return size < (maximumAllocation * invMat.getScaleX() * invMat.getScaleY());
}

static SkScalar effective_matrix_scale_sqrd(const SkMatrix& mat) {
    SkPoint v1, v2;

    v1.fX = mat.getScaleX();
    v1.fY = mat.getSkewY();

    v2.fX = mat.getSkewX();
    v2.fY = mat.getScaleY();

    return SkMaxScalar(v1.lengthSqd(), v2.lengthSqd());
}

// Check to see that the size of the bitmap that would be produced by
// scaling by the given inverted matrix is less than the maximum allowed.
static inline bool cache_size_okay(const SkBitmap& bm, const SkMatrix& invMat) {
    size_t maximumAllocation
        = SkScaledImageCache::GetSingleAllocationByteLimit();
    if (0 == maximumAllocation) {
        return true;
    }
    // float matrixScaleFactor = 1.0 / (invMat.scaleX * invMat.scaleY);
    // return ((origBitmapSize * matrixScaleFactor) < maximumAllocationSize);
    // Skip the division step:
    return bm.info().getSafeSize(bm.info().minRowBytes())
        < (maximumAllocation * invMat.getScaleX() * invMat.getScaleY());
}

void SkDeferredCanvas::Rec::setConcat(const SkMatrix& m) {
    SkASSERT(m.getType() <= (SkMatrix::kScale_Mask | SkMatrix::kTranslate_Mask));
    
    if (m.getType() <= SkMatrix::kTranslate_Mask) {
        fType = kTrans_Type;
        fData.fTranslate.set(m.getTranslateX(), m.getTranslateY());
    } else {
        fType = kScaleTrans_Type;
        fData.fScaleTrans.fScale.set(m.getScaleX(), m.getScaleY());
        fData.fScaleTrans.fTrans.set(m.getTranslateX(), m.getTranslateY());
    }
}

SkScalerContext_Ascender::SkScalerContext_Ascender(const SkDescriptor* desc)
    : SkScalerContext(desc)
{
    int size = aca_Get_FontHandleRec_Size();
    fHandle = (aca_FontHandle)sk_malloc_throw(size);
    
    // get the pointer to the font
    
    fFontStream = new SkMMAPStream("/UcsGB2312-Hei-H.FDL");
    fHintStream = new SkMMAPStream("/genv6-23.bin");
    
    void* hints = sk_malloc_throw(fHintStream->getLength());
    memcpy(hints, fHintStream->getMemoryBase(), fHintStream->getLength());
    
    aca_Create_Font_Handle(fHandle,
                           (void*)fFontStream->getMemoryBase(), fFontStream->getLength(),
                           "fred",
                           hints, fHintStream->getLength());
    
    // compute our factors from the record

    SkMatrix    m;

    fRec.getSingleMatrix(&m);

    //  now compute our scale factors
    SkScalar    sx = m.getScaleX();
    SkScalar    sy = m.getScaleY();
    
    int ppemX = SkScalarRound(sx);
    int ppemY = SkScalarRound(sy);
    
    size = aca_Find_Font_Memory_Required(fHandle, ppemX, ppemY);
    size *= 8;  // Jeff suggests this :)
    fWorkspace = sk_malloc_throw(size);
    aca_Set_Font_Memory(fHandle, (uint8_t*)fWorkspace, size);

    aca_GlyphAttribsRec rec;
    
    memset(&rec, 0, sizeof(rec));
    rec.xSize = ppemX;
    rec.ySize = ppemY;
    rec.doAdjust = true;
    rec.doExceptions = true;
    rec.doGlyphHints = true;
    rec.doInterpolate = true;
    rec.grayMode = 2;
    aca_Set_Font_Attributes(fHandle, &rec, &size);
    
    fGlyphWorkspace = sk_malloc_throw(size);
    aca_Set_Glyph_Memory(fHandle, fGlyphWorkspace);
}

void SkLatticeIter::mapDstScaleTranslate(const SkMatrix& matrix) {
    SkASSERT(matrix.isScaleTranslate());
    SkScalar tx = matrix.getTranslateX();
    SkScalar sx = matrix.getScaleX();
    for (int i = 0; i < fDstX.count(); i++) {
        fDstX[i] = fDstX[i] * sx + tx;
    }

    SkScalar ty = matrix.getTranslateY();
    SkScalar sy = matrix.getScaleY();
    for (int i = 0; i < fDstY.count(); i++) {
        fDstY[i] = fDstY[i] * sy + ty;
    }
}

void SkGScalerContext::generateFontMetrics(SkPaint::FontMetrics* metrics) {
    fProxy->getFontMetrics(metrics);
    if (metrics) {
        SkScalar scale = fMatrix.getScaleY();
        metrics->fTop = SkScalarMul(metrics->fTop, scale);
        metrics->fAscent = SkScalarMul(metrics->fAscent, scale);
        metrics->fDescent = SkScalarMul(metrics->fDescent, scale);
        metrics->fBottom = SkScalarMul(metrics->fBottom, scale);
        metrics->fLeading = SkScalarMul(metrics->fLeading, scale);
        metrics->fAvgCharWidth = SkScalarMul(metrics->fAvgCharWidth, scale);
        metrics->fXMin = SkScalarMul(metrics->fXMin, scale);
        metrics->fXMax = SkScalarMul(metrics->fXMax, scale);
        metrics->fXHeight = SkScalarMul(metrics->fXHeight, scale);
    }
}

GrCCPathCache::MaskTransform::MaskTransform(const SkMatrix& m, SkIVector* shift)
        : fMatrix2x2{m.getScaleX(), m.getSkewX(), m.getSkewY(), m.getScaleY()} {
    SkASSERT(!m.hasPerspective());
    Sk2f translate = Sk2f(m.getTranslateX(), m.getTranslateY());
    Sk2f transFloor;
#ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
    // On Android framework we pre-round view matrix translates to integers for better caching.
    transFloor = translate;
#else
    transFloor = translate.floor();
    (translate - transFloor).store(fSubpixelTranslate);
#endif
    shift->set((int)transFloor[0], (int)transFloor[1]);
    SkASSERT((float)shift->fX == transFloor[0]);  // Make sure transFloor had integer values.
    SkASSERT((float)shift->fY == transFloor[1]);
}

static void calculate_translation(bool applyVM,
                                  const SkMatrix& newViewMatrix, SkScalar newX, SkScalar newY,
                                  const SkMatrix& currentViewMatrix, SkScalar currentX,
                                  SkScalar currentY, SkScalar* transX, SkScalar* transY) {
    if (applyVM) {
        *transX = newViewMatrix.getTranslateX() +
                  newViewMatrix.getScaleX() * (newX - currentX) +
                  newViewMatrix.getSkewX() * (newY - currentY) -
                  currentViewMatrix.getTranslateX();

        *transY = newViewMatrix.getTranslateY() +
                  newViewMatrix.getSkewY() * (newX - currentX) +
                  newViewMatrix.getScaleY() * (newY - currentY) -
                  currentViewMatrix.getTranslateY();
    } else {
        *transX = newX - currentX;
        *transY = newY - currentY;
    }
}

SkLinearBitmapPipeline::SkLinearBitmapPipeline(
    const SkMatrix& inverse,
    SkFilterQuality filterQuality,
    SkShader::TileMode xTile, SkShader::TileMode yTile,
    SkColor paintColor,
    const SkPixmap& srcPixmap)
{
    SkISize dimensions = srcPixmap.info().dimensions();
    const SkImageInfo& srcImageInfo = srcPixmap.info();

    SkMatrix adjustedInverse = inverse;
    if (filterQuality == kNone_SkFilterQuality) {
        if (inverse.getScaleX() >= 0.0f) {
            adjustedInverse.setTranslateX(
                nextafterf(inverse.getTranslateX(), std::floor(inverse.getTranslateX())));
        }
        if (inverse.getScaleY() >= 0.0f) {
            adjustedInverse.setTranslateY(
                nextafterf(inverse.getTranslateY(), std::floor(inverse.getTranslateY())));
        }
    }

    SkScalar dx = adjustedInverse.getScaleX();

    // If it is an index 8 color type, the sampler converts to unpremul for better fidelity.
    SkAlphaType alphaType = srcImageInfo.alphaType();
    if (srcPixmap.colorType() == kIndex_8_SkColorType) {
        alphaType = kUnpremul_SkAlphaType;
    }

    float postAlpha = SkColorGetA(paintColor) * (1.0f / 255.0f);
    // As the stages are built, the chooser function may skip a stage. For example, with the
    // identity matrix, the matrix stage is skipped, and the tilerStage is the first stage.
    auto blenderStage = choose_blender_for_shading(alphaType, postAlpha, &fBlenderStage);
    auto samplerStage = choose_pixel_sampler(
        blenderStage, filterQuality, xTile, yTile,
        srcPixmap, paintColor, &fSampleStage, &fAccessor);
    auto tilerStage   = choose_tiler(samplerStage, dimensions, xTile, yTile,
                                     filterQuality, dx, &fTileStage);
    fFirstStage       = choose_matrix(tilerStage, adjustedInverse, &fMatrixStage);
    fLastStage        = blenderStage;
}

void SkFlatMatrix::dump() const {
    const SkMatrix* matrix = (const SkMatrix*) fMatrixData;
    char pBuffer[DUMP_BUFFER_SIZE];
    char* bufferPtr = pBuffer;
    bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
    "matrix: ");
    SkScalar scaleX = matrix->getScaleX();
    SkMatrix defaultMatrix;
    defaultMatrix.reset();
    if (scaleX != defaultMatrix.getScaleX())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "scaleX:%g ", SkScalarToFloat(scaleX));
    SkScalar scaleY = matrix->getScaleY();
    if (scaleY != defaultMatrix.getScaleY())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "scaleY:%g ", SkScalarToFloat(scaleY));
    SkScalar skewX = matrix->getSkewX();
    if (skewX != defaultMatrix.getSkewX())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "skewX:%g ", SkScalarToFloat(skewX));
    SkScalar skewY = matrix->getSkewY();
    if (skewY != defaultMatrix.getSkewY())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "skewY:%g ", SkScalarToFloat(skewY));
    SkScalar translateX = matrix->getTranslateX();
    if (translateX != defaultMatrix.getTranslateX())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "translateX:%g ", SkScalarToFloat(translateX));
    SkScalar translateY = matrix->getTranslateY();
    if (translateY != defaultMatrix.getTranslateY())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "translateY:%g ", SkScalarToFloat(translateY));
    SkScalar perspX = matrix->getPerspX();
    if (perspX != defaultMatrix.getPerspX())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "perspX:%g ", SkFractToFloat(perspX));
    SkScalar perspY = matrix->getPerspY();
    if (perspY != defaultMatrix.getPerspY())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "perspY:%g ", SkFractToFloat(perspY));
    SkDebugf("%s\n", pBuffer);
}

bool SkDeferredCanvas::push_concat(const SkMatrix& mat) {
    if (mat.getType() > (SkMatrix::kScale_Mask | SkMatrix::kTranslate_Mask)) {
        return false;
    }
    // At the moment, we don't know which ops can scale and which can also flip, so
    // we reject negative scales for now
    if (mat.getScaleX() < 0 || mat.getScaleY() < 0) {
        return false;
    }

    int index = fRecs.count() - 1;
    SkMatrix m;
    if (index >= 0 && fRecs[index].isConcat(&m)) {
        m.preConcat(mat);
        fRecs[index].setConcat(m);
    } else {
        fRecs.append()->setConcat(mat);
    }
    return true;
}

void SkDumpCanvas::didConcat(const SkMatrix& matrix) {
    SkString str;

    switch (matrix.getType()) {
        case SkMatrix::kTranslate_Mask:
            this->dump(kMatrix_Verb, nullptr, "translate(%g %g)",
                       SkScalarToFloat(matrix.getTranslateX()),
                       SkScalarToFloat(matrix.getTranslateY()));
            break;
        case SkMatrix::kScale_Mask:
            this->dump(kMatrix_Verb, nullptr, "scale(%g %g)",
                       SkScalarToFloat(matrix.getScaleX()),
                       SkScalarToFloat(matrix.getScaleY()));
            break;
        default:
            matrix.toString(&str);
            this->dump(kMatrix_Verb, nullptr, "concat(%s)", str.c_str());
            break;
    }

    this->INHERITED::didConcat(matrix);
}

void LoggingCanvas::didConcat(const SkMatrix& matrix)
{
    AutoLogger logger(this);
    RefPtr<JSONObject> params;

    switch (matrix.getType()) {
    case SkMatrix::kTranslate_Mask:
        params = logger.logItemWithParams("translate");
        params->setNumber("dx", matrix.getTranslateX());
        params->setNumber("dy", matrix.getTranslateY());
        break;

    case SkMatrix::kScale_Mask:
        params = logger.logItemWithParams("scale");
        params->setNumber("scaleX", matrix.getScaleX());
        params->setNumber("scaleY", matrix.getScaleY());
        break;

    default:
        params = logger.logItemWithParams("concat");
        params->setArray("matrix", arrayForSkMatrix(matrix));
    }
    this->SkCanvas::didConcat(matrix);
}

void NativeImageSkia::drawPattern(
    GraphicsContext* context,
    const FloatRect& floatSrcRect,
    const FloatSize& scale,
    const FloatPoint& phase,
    CompositeOperator compositeOp,
    const FloatRect& destRect,
    blink::WebBlendMode blendMode,
    const IntSize& repeatSpacing) const
{
    FloatRect normSrcRect = floatSrcRect;
    normSrcRect.intersect(FloatRect(0, 0, bitmap().width(), bitmap().height()));
    if (destRect.isEmpty() || normSrcRect.isEmpty())
        return; // nothing to draw

    SkMatrix totalMatrix = context->getTotalMatrix();
    SkScalar ctmScaleX = totalMatrix.getScaleX();
    SkScalar ctmScaleY = totalMatrix.getScaleY();
    totalMatrix.preScale(scale.width(), scale.height());

    // Figure out what size the bitmap will be in the destination. The
    // destination rect is the bounds of the pattern, we need to use the
    // matrix to see how big it will be.
    SkRect destRectTarget;
    totalMatrix.mapRect(&destRectTarget, normSrcRect);

    float destBitmapWidth = SkScalarToFloat(destRectTarget.width());
    float destBitmapHeight = SkScalarToFloat(destRectTarget.height());

    // Compute the resampling mode.
    ResamplingMode resampling;
    if (context->isAccelerated() || context->printing())
        resampling = LinearResampling;
    else
        resampling = computeResamplingMode(totalMatrix, normSrcRect.width(), normSrcRect.height(), destBitmapWidth, destBitmapHeight);
    resampling = limitResamplingMode(context, resampling);

    SkMatrix shaderTransform;
    RefPtr<SkShader> shader;

    bool isLazyDecoded = DeferredImageDecoder::isLazyDecoded(bitmap());
    // Bicubic filter is only applied to defer-decoded images, see
    // NativeImageSkia::draw for details.
    bool useBicubicFilter = resampling == AwesomeResampling && isLazyDecoded;

    if (resampling == AwesomeResampling && !useBicubicFilter) {
        // Do nice resampling.
        float scaleX = destBitmapWidth / normSrcRect.width();
        float scaleY = destBitmapHeight / normSrcRect.height();
        SkRect scaledSrcRect;

        // The image fragment generated here is not exactly what is
        // requested. The scale factor used is approximated and image
        // fragment is slightly larger to align to integer
        // boundaries.
        SkBitmap resampled = extractScaledImageFragment(normSrcRect, scaleX, scaleY, &scaledSrcRect);
        if (repeatSpacing.isZero()) {
            shader = adoptRef(SkShader::CreateBitmapShader(resampled, SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode));
        } else {
            shader = adoptRef(SkShader::CreateBitmapShader(
                createBitmapWithSpace(resampled, repeatSpacing.width() * ctmScaleX, repeatSpacing.height() * ctmScaleY),
                SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode));
        }

        // Since we just resized the bitmap, we need to remove the scale
        // applied to the pixels in the bitmap shader. This means we need
        // CTM * shaderTransform to have identity scale. Since we
        // can't modify CTM (or the rectangle will be drawn in the wrong
        // place), we must set shaderTransform's scale to the inverse of
        // CTM scale.
        shaderTransform.setScale(ctmScaleX ? 1 / ctmScaleX : 1, ctmScaleY ? 1 / ctmScaleY : 1);
    } else {
        // No need to resample before drawing.
        SkBitmap srcSubset;
        bitmap().extractSubset(&srcSubset, enclosingIntRect(normSrcRect));
        if (repeatSpacing.isZero()) {
            shader = adoptRef(SkShader::CreateBitmapShader(srcSubset, SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode));
        } else {
            shader = adoptRef(SkShader::CreateBitmapShader(
                createBitmapWithSpace(srcSubset, repeatSpacing.width() * ctmScaleX, repeatSpacing.height() * ctmScaleY),
                SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode));
        }

        // Because no resizing occurred, the shader transform should be
        // set to the pattern's transform, which just includes scale.
        shaderTransform.setScale(scale.width(), scale.height());
    }

    // We also need to translate it such that the origin of the pattern is the
    // origin of the destination rect, which is what WebKit expects. Skia uses
    // the coordinate system origin as the base for the pattern. If WebKit wants
    // a shifted image, it will shift it from there using the shaderTransform.
    float adjustedX = phase.x() + normSrcRect.x() * scale.width();
    float adjustedY = phase.y() + normSrcRect.y() * scale.height();
    shaderTransform.postTranslate(SkFloatToScalar(adjustedX), SkFloatToScalar(adjustedY));
    shader->setLocalMatrix(shaderTransform);

    SkPaint paint;
    paint.setShader(shader.get());
    paint.setXfermode(WebCoreCompositeToSkiaComposite(compositeOp, blendMode).get());
//.........这里部分代码省略.........