C++ SkISize类代码示例

// Creates an SkImage that is backed by SkDiscardablePixelRef.
PassRefPtr<SkImage> DeferredImageDecoder::createImage(size_t index, bool knownToBeOpaque) const
{
    SkISize decodedSize = m_frameGenerator->getFullSize();
    ASSERT(decodedSize.width() > 0);
    ASSERT(decodedSize.height() > 0);

    const SkImageInfo info = SkImageInfo::MakeN32(decodedSize.width(), decodedSize.height(),
        knownToBeOpaque ? kOpaque_SkAlphaType : kPremul_SkAlphaType);

    DecodingImageGenerator* generator = new DecodingImageGenerator(m_frameGenerator, info, index);
    RefPtr<SkImage> image = adoptRef(SkImage::NewFromGenerator(generator));
    if (!image)
        return nullptr;

    generator->setGenerationId(image->uniqueID());
    return image.release();
}

SkSVGDevice::SkSVGDevice(const SkISize& size, SkXMLWriter* writer)
    : fWriter(writer)
    , fResourceBucket(SkNEW(ResourceBucket)) {
    SkASSERT(writer);

    fLegacyBitmap.setInfo(SkImageInfo::MakeUnknown(size.width(), size.height()));

    fWriter->writeHeader();

    // The root <svg> tag gets closed by the destructor.
    fRootElement.reset(SkNEW_ARGS(AutoElement, ("svg", fWriter)));

    fRootElement->addAttribute("xmlns", "http://www.w3.org/2000/svg");
    fRootElement->addAttribute("xmlns:xlink", "http://www.w3.org/1999/xlink");
    fRootElement->addAttribute("width", size.width());
    fRootElement->addAttribute("height", size.height());
}

SkSVGDevice::SkSVGDevice(const SkISize& size, SkXMLWriter* writer)
    : INHERITED(SkImageInfo::MakeUnknown(size.fWidth, size.fHeight),
                SkSurfaceProps(0, kUnknown_SkPixelGeometry))
    , fWriter(writer)
    , fResourceBucket(new ResourceBucket)
{
    SkASSERT(writer);

    fWriter->writeHeader();

    // The root <svg> tag gets closed by the destructor.
    fRootElement.reset(new AutoElement("svg", fWriter));

    fRootElement->addAttribute("xmlns", "http://www.w3.org/2000/svg");
    fRootElement->addAttribute("xmlns:xlink", "http://www.w3.org/1999/xlink");
    fRootElement->addAttribute("width", size.width());
    fRootElement->addAttribute("height", size.height());
}

static void drawJpeg(SkCanvas* canvas, const SkISize& size) {
    // TODO: Make this draw a file that is checked in, so it can
    // be exercised on machines other than mike's. Will require a
    // rebaseline.
    SkAutoDataUnref data(SkData::NewFromFileName("/Users/mike/Downloads/skia.google.jpeg"));
    if (NULL == data.get()) {
        return;
    }
    SkImage* image = SkImage::NewFromGenerator(
                SkDecodingImageGenerator::Create(data, SkDecodingImageGenerator::Options()));
    if (image) {
        SkAutoCanvasRestore acr(canvas, true);
        canvas->scale(size.width() * 1.0f / image->width(),
                      size.height() * 1.0f / image->height());
        canvas->drawImage(image, 0, 0, NULL);
        image->unref();
    }
}

// Static function to create a 2D convolution
std::unique_ptr<GrFragmentProcessor> GrMatrixConvolutionEffect::MakeGaussian(
        sk_sp<GrTextureProxy> proxy,
        const SkIRect& bounds,
        const SkISize& kernelSize,
        SkScalar gain,
        SkScalar bias,
        const SkIPoint& kernelOffset,
        GrTextureDomain::Mode tileMode,
        bool convolveAlpha,
        SkScalar sigmaX,
        SkScalar sigmaY) {
    float kernel[MAX_KERNEL_SIZE];

    fill_in_2D_gaussian_kernel(kernel, kernelSize.width(), kernelSize.height(), sigmaX, sigmaY);

    return std::unique_ptr<GrFragmentProcessor>(
            new GrMatrixConvolutionEffect(std::move(proxy), bounds, kernelSize, kernel, gain, bias,
                                          kernelOffset, tileMode, convolveAlpha));
}

void TileGridTask::draw() {
    const SkTileGridPicture::TileGridInfo info = {
        fTileSize,
        SkISize::Make(0,0),   // Overlap between adjacent tiles.
        SkIPoint::Make(0,0),  // Offset.
    };
    const SkISize size = fGM->getISize();
    SkTileGridPicture recorded(size.width(), size.height(), info);
    RecordPicture(fGM.get(), &recorded, SkPicture::kUsePathBoundsForClip_RecordingFlag);

    SkBitmap full;
    SetupBitmap(fReference.colorType(), fGM.get(), &full);
    SkCanvas fullCanvas(full);

    SkBitmap tile;
    tile.allocPixels(SkImageInfo::Make(fTileSize.width(), fTileSize.height(),
                                       fReference.colorType(), kPremul_SkAlphaType));
    SkCanvas tileCanvas(tile);

    SkPaint paint;
    paint.setXfermodeMode(SkXfermode::kSrc_Mode);

    for (int y = 0; y < tiles_needed(full.height(), tile.height()); y++) {
        for (int x = 0; x < tiles_needed(full.width(), tile.width()); x++) {
            SkAutoCanvasRestore ar(&tileCanvas, true/*also save now*/);

            const SkScalar xOffset = SkIntToScalar(x * tile.width()),
                           yOffset = SkIntToScalar(y * tile.height());
            SkMatrix matrix = tileCanvas.getTotalMatrix();
            matrix.postTranslate(-xOffset, -yOffset);
            tileCanvas.setMatrix(matrix);

            recorded.draw(&tileCanvas);
            tileCanvas.flush();
            fullCanvas.drawBitmap(tile, xOffset, yOffset, &paint);
        }
    }

    if (!BitmapsEqual(full, fReference)) {
        this->fail();
        this->spawnChild(SkNEW_ARGS(WriteTask, (*this, full)));
    }
}

// calculates sampleSize in x and y direction
void SkScaledCodec::ComputeSampleSize(const SkISize& dstDim, const SkISize& srcDim,
                                      int* sampleXPtr, int* sampleYPtr) {
    int srcWidth = srcDim.width();
    int dstWidth = dstDim.width();
    int srcHeight = srcDim.height();
    int dstHeight = dstDim.height();

    int sampleX = srcWidth / dstWidth;
    int sampleY = srcHeight / dstHeight;

    // only support down sampling, not up sampling
    SkASSERT(dstWidth <= srcWidth);
    SkASSERT(dstHeight <= srcHeight);

    // sampleX and sampleY should be equal unless the original sampleSize requested was
    // larger than srcWidth or srcHeight.
    // If so, the result of this is dstWidth or dstHeight = 1. This functionality
    // allows for tall thin images to still be scaled down by scaling factors.

    if (sampleX != sampleY){
        if (1 != dstWidth && 1 != dstHeight) {

            // rounding during onGetScaledDimensions can cause different sampleSizes
            // Ex: srcWidth = 79, srcHeight = 20, sampleSize = 10
            // dstWidth = 7, dstHeight = 2, sampleX = 79/7 = 11, sampleY = 20/2 = 10
            // correct for this rounding by comparing width to sampleY and height to sampleX

            if (get_scaled_dimension(srcWidth, sampleY) == dstWidth) {
                sampleX = sampleY;
            } else if (get_scaled_dimension(srcHeight, sampleX) == dstHeight) {
                sampleY = sampleX;
            }
        }
    }

    if (sampleXPtr) {
        *sampleXPtr = sampleX;
    }
    if (sampleYPtr) {
        *sampleYPtr = sampleY;
    }
}

/*
If you execute skp_parser with one argument, it spits out a json representation
of the skp, but that's incomplete since it's missing many binary blobs (these
could represent images or typefaces or just anything that doesn't currently
have a json representation).  Each unique blob is labeled with a string in the
form "data/%d".  So for example:

    tools/git-sync-deps
    bin/gn gen out/debug
    ninja -C out/debug dm skp_parser
    out/debug/dm -m grayscale -w /tmp/dm --config skp
    out/debug/skp_parser /tmp/dm/skp/gm/grayscalejpg.skp | less
    out/debug/skp_parser /tmp/dm/skp/gm/grayscalejpg.skp | grep data
    out/debug/skp_parser /tmp/dm/skp/gm/grayscalejpg.skp data/0 | file -
    out/debug/skp_parser /tmp/dm/skp/gm/grayscalejpg.skp data/0 > /tmp/data0.png

"data/0" is an image that the SKP serializer has encoded as PNG.
*/
int main(int argc, char** argv) {
    if (argc < 2) {
        SkDebugf("Usage:\n  %s SKP_FILE [DATA_URL]\n", argv[0]);
        return 1;
    }
    SkFILEStream input(argv[1]);
    if (!input.isValid()) {
        SkDebugf("Bad file: '%s'\n", argv[1]);
        return 2;
    }
    sk_sp<SkPicture> pic = SkPicture::MakeFromStream(&input);
    if (!pic) {
        SkDebugf("Bad skp: '%s'\n", argv[1]);
        return 3;
    }
    SkISize size = pic->cullRect().roundOut().size();
    SkDebugCanvas debugCanvas(size.width(), size.height());
    pic->playback(&debugCanvas);
    std::unique_ptr<SkCanvas> nullCanvas = SkMakeNullCanvas();
    UrlDataManager dataManager(SkString("data"));
    Json::Value json = debugCanvas.toJSON(
            dataManager, debugCanvas.getSize(), nullCanvas.get());
    if (argc > 2) {
        if (UrlDataManager::UrlData* data =
            dataManager.getDataFromUrl(SkString(argv[2]))) {
            SkData* skdata = data->fData.get();
            SkASSERT(skdata);
            #ifdef SK_BUILD_FOR_WIN
            fflush(stdout);
            (void)_setmode(_fileno(stdout), _O_BINARY);
            #endif
            fwrite(skdata->data(), skdata->size(), 1, stdout);
        } else {
            SkDebugf("Bad data url.\n");
            return 4;
        }
    } else {
        Json::StyledStreamWriter("  ").write(std::cout, json);
    }
    return 0;
}

// Creates a SkBitmap that is backed by SkDiscardablePixelRef.
SkBitmap DeferredImageDecoder::createBitmap(size_t index)
{
    SkISize decodedSize = m_frameGenerator->getFullSize();
    ASSERT(decodedSize.width() > 0);
    ASSERT(decodedSize.height() > 0);

#if SK_B32_SHIFT // Little-endian RGBA pixels. (Android)
    const SkColorType colorType = kRGBA_8888_SkColorType;
#else
    const SkColorType colorType = kBGRA_8888_SkColorType;
#endif
    const SkImageInfo info = SkImageInfo::Make(decodedSize.width(), decodedSize.height(), colorType, kPremul_SkAlphaType);

    SkBitmap bitmap;
    DecodingImageGenerator* generator = new DecodingImageGenerator(m_frameGenerator, info, index);
    bool installed = SkInstallDiscardablePixelRef(generator, &bitmap);
    ASSERT_UNUSED(installed, installed);
    bitmap.pixelRef()->setURI(labelDiscardable);
    generator->setGenerationId(bitmap.getGenerationID());
    return bitmap;
}

    void drawTheImage(SkCanvas* canvas, const SkISize& size, SkFilterQuality filter,
                      SkScalar dx, SkScalar dy) {
        SkPaint paint;
        paint.setAntiAlias(true);
        paint.setFilterQuality(filter);

        SkAutoCanvasRestore acr(canvas, true);

        canvas->translate(dx, dy);

        canvas->translate(SkScalarHalf(size.width()), SkScalarHalf(size.height()));
        canvas->scale(fScale, fScale);
        canvas->rotate(fAngle);
        canvas->drawImage(fImage, -SkScalarHalf(fImage->width()), -SkScalarHalf(fImage->height()),
                          &paint);

        if (false) {
            acr.restore();
            draw_box_frame(canvas, size.width(), size.height());
        }
    }

void Viewer::setupCurrentSlide(int previousSlide) {
    if (fCurrentSlide == previousSlide) {
        return; // no change; do nothing
    }

    fGesture.reset();
    fDefaultMatrix.reset();
    fDefaultMatrixInv.reset();

    if (fWindow->supportsContentRect() && fWindow->scaleContentToFit()) {
        const SkRect contentRect = fWindow->getContentRect();
        const SkISize slideSize = fSlides[fCurrentSlide]->getDimensions();
        const SkRect slideBounds = SkRect::MakeIWH(slideSize.width(), slideSize.height());
        if (contentRect.width() > 0 && contentRect.height() > 0) {
            fDefaultMatrix.setRectToRect(slideBounds, contentRect, SkMatrix::kStart_ScaleToFit);
            SkAssertResult(fDefaultMatrix.invert(&fDefaultMatrixInv));
        }
    }

    if (fWindow->supportsContentRect()) {
        const SkISize slideSize = fSlides[fCurrentSlide]->getDimensions();
        SkRect windowRect = fWindow->getContentRect();
        fDefaultMatrixInv.mapRect(&windowRect);
        fGesture.setTransLimit(SkRect::MakeWH(slideSize.width(), slideSize.height()), windowRect);
    }

    this->updateTitle();
    this->updateUIState();
    fSlides[fCurrentSlide]->load();
    if (previousSlide >= 0) {
        fSlides[previousSlide]->unload();
    }
    fWindow->inval();
}

    void onDraw(int loops, SkCanvas* canvas) override {
        canvas->clear(SK_ColorBLACK);

        SkISize size = canvas->getDeviceSize();

        int offX = (size.width() - kWindowSize) / kNumStepsX;
        int offY = (size.height() - kWindowSize) / kNumStepsY;

        SkPaint paint;

        paint.setColor(SK_ColorBLUE);

        canvas->drawCircle(SkIntToScalar(size.width()/2),
                           SkIntToScalar(size.height()/2),
                           SkIntToScalar(size.width()/2),
                           paint);

        SkBitmap bitmap;

        bitmap.setInfo(SkImageInfo::MakeN32Premul(kWindowSize, kWindowSize));

        for (int i = 0; i < loops; i++) {
            for (int x = 0; x < kNumStepsX; ++x) {
                for (int y = 0; y < kNumStepsY; ++y) {
                    canvas->readPixels(&bitmap, x * offX, y * offY);
                }
            }
        }
    }

static SkISize best_scaled_dimensions(const SkISize& origDims, const SkISize& nativeDims,
                                      const SkISize& scaledCodecDims, float desiredScale) {
    if (nativeDims == scaledCodecDims) {
        // does not matter which to return if equal. Return here to skip below calculations
        return nativeDims;
    }
    float idealWidth = origDims.width() * desiredScale;
    float idealHeight = origDims.height() * desiredScale;

    // calculate difference between native dimensions and ideal dimensions
    float nativeWDiff = SkTAbs(idealWidth - nativeDims.width());
    float nativeHDiff = SkTAbs(idealHeight - nativeDims.height());
    float nativeDiff = nativeWDiff + nativeHDiff;

    // Native scaling is preferred to sampling.  If we can scale natively to
    // within one of the ideal value, we should choose to scale natively.
    if (nativeWDiff < 1.0f && nativeHDiff < 1.0f) {
        return nativeDims;
    }

    // calculate difference between scaledCodec dimensions and ideal dimensions
    float scaledCodecWDiff = SkTAbs(idealWidth - scaledCodecDims.width());
    float scaledCodecHDiff = SkTAbs(idealHeight - scaledCodecDims.height());
    float scaledCodecDiff = scaledCodecWDiff + scaledCodecHDiff;

    // return dimensions closest to ideal dimensions.
    // If the differences are equal, return nativeDims, as native scaling is more efficient.
    return nativeDiff > scaledCodecDiff ? scaledCodecDims : nativeDims;
}

void GMSampleView::onDrawContent(SkCanvas* canvas) {
    SkPictureRecorder recorder;
    SkCanvas* origCanvas = canvas;

    if (false) {
        SkISize size = fGM->getISize();
        canvas = recorder.beginRecording(SkRect::MakeIWH(size.width(), size.height()));
    }

    {
        SkAutoCanvasRestore acr(canvas, fShowSize);
        fGM->drawContent(canvas);
    }

    if (origCanvas != canvas) {
        sk_sp<SkPicture> pic = recorder.finishRecordingAsPicture();
        if (false) {
            pic = round_trip_serialize(pic.get());
        }
        origCanvas->drawPicture(pic);
        canvas = origCanvas;
    }

    if (fShowSize) {
        SkISize size = fGM->getISize();
        SkRect r = SkRect::MakeWH(SkIntToScalar(size.width()),
                                  SkIntToScalar(size.height()));
        SkPaint paint;
        paint.setColor(0x40FF8833);
        canvas->drawRect(r, paint);
    }
}

GrMatrixConvolutionEffect::GrMatrixConvolutionEffect(GrTexture* texture,
                                                     const SkIRect& bounds,
                                                     const SkISize& kernelSize,
                                                     const SkScalar* kernel,
                                                     SkScalar gain,
                                                     SkScalar bias,
                                                     const SkIPoint& kernelOffset,
                                                     GrTextureDomain::Mode tileMode,
                                                     bool convolveAlpha)
  : INHERITED(texture, GrCoordTransform::MakeDivByTextureWHMatrix(texture)),
    fKernelSize(kernelSize),
    fGain(SkScalarToFloat(gain)),
    fBias(SkScalarToFloat(bias) / 255.0f),
    fConvolveAlpha(convolveAlpha),
    fDomain(GrTextureDomain::MakeTexelDomainForMode(texture, bounds, tileMode), tileMode) {
    this->initClassID<GrMatrixConvolutionEffect>();
    for (int i = 0; i < kernelSize.width() * kernelSize.height(); i++) {
        fKernel[i] = SkScalarToFloat(kernel[i]);
    }
    fKernelOffset[0] = static_cast<float>(kernelOffset.x());
    fKernelOffset[1] = static_cast<float>(kernelOffset.y());
}