C++ FloatRect::setWidth方法代码示例

bool RenderThemeWinCE::paintMediaPlayButton(RenderObject* o, const PaintInfo& paintInfo, const IntRect& r)
{
    bool rc = paintButton(o, paintInfo, r);
    FloatRect imRect = r;
    imRect.inflate(-3);
    paintInfo.context->save();
    paintInfo.context->setStrokeColor(Color::black);
    paintInfo.context->setFillColor(Color::black);
    HTMLMediaElement* mediaElement = mediaElementParent(o->node());
    bool paused = !mediaElement || mediaElement->paused();
    if (paused) {
        float width = imRect.width();
        imRect.setWidth(width / 3.0);
        paintInfo.context->fillRect(imRect);
        imRect.move(2.0 * width / 3.0, 0);
        paintInfo.context->fillRect(imRect);
    } else {
        FloatPoint pts[3] = { FloatPoint(imRect.x(), imRect.y()), FloatPoint(imRect.maxX(), (imRect.y() + imRect.maxY()) / 2.0), FloatPoint(imRect.x(), imRect.maxY()) };
        paintInfo.context->drawConvexPolygon(3, pts);
    }
    paintInfo.context->restore();
    return rc;
}

void ImageBuffer::drawPattern(GraphicsContext* context, const FloatRect& srcRect, const AffineTransform& patternTransform,
                              const FloatPoint& phase, ColorSpace styleColorSpace, CompositeOperator op, const FloatRect& dstRect)
{
    if (m_data.m_tiledImage && context != m_context.get()) {
        FloatRect src = srcRect;
        if (src.width() == -1)
            src.setWidth(m_data.m_tiledImage->size().width());
        if (src.height() == -1)
            src.setHeight(m_data.m_tiledImage->size().height());

        ASSERT(context->platformContext()->activePainter());

        AffineTransform phasedPatternTransform;
        phasedPatternTransform.translate(phase.x(), phase.y());
        phasedPatternTransform.multLeft(patternTransform);

        PatternOpenVG pattern(m_data.m_tiledImage, src);
        pattern.setTransformation(phasedPatternTransform);

        PainterOpenVG* painter = context->platformContext()->activePainter();

        PaintOpenVG currentPaint = painter->fillPaint();
        CompositeOperator currentOp = painter->compositeOperation();

        painter->setCompositeOperation(op);
        painter->setFillPattern(pattern);
        painter->drawRect(dstRect, VG_FILL_PATH);

        painter->setFillPaint(currentPaint);
        painter->setCompositeOperation(currentOp);
        return;
    }

    RefPtr<Image> imageCopy = copyImage();
    imageCopy->drawPattern(context, srcRect, patternTransform, phase, styleColorSpace, op, dstRect);
}

FloatRect GraphicsContext::roundToDevicePixels(const FloatRect& frect, RoundingMode)
{
    FloatRect result;
    double x = frect.x();
    double y = frect.y();
    cairo_t* cr = platformContext()->cr();
    cairo_user_to_device(cr, &x, &y);
    x = round(x);
    y = round(y);
    cairo_device_to_user(cr, &x, &y);
    result.setX(narrowPrecisionToFloat(x));
    result.setY(narrowPrecisionToFloat(y));

    // We must ensure width and height are at least 1 (or -1) when
    // we're given float values in the range between 0 and 1 (or -1 and 0).
    double width = frect.width();
    double height = frect.height();
    cairo_user_to_device_distance(cr, &width, &height);
    if (width > -1 && width < 0)
        width = -1;
    else if (width > 0 && width < 1)
        width = 1;
    else
        width = round(width);
    if (height > -1 && width < 0)
        height = -1;
    else if (height > 0 && height < 1)
        height = 1;
    else
        height = round(height);
    cairo_device_to_user_distance(cr, &width, &height);
    result.setWidth(narrowPrecisionToFloat(width));
    result.setHeight(narrowPrecisionToFloat(height));

    return result;
}

void Gradient::adjustParametersForTiledDrawing(FloatSize& size, FloatRect& srcRect, const FloatSize& spacing)
{
    if (m_radial)
        return;

    if (srcRect.isEmpty())
        return;

    if (!spacing.isZero())
        return;

    if (m_p0.x() == m_p1.x()) {
        size.setWidth(1);
        srcRect.setWidth(1);
        srcRect.setX(0);
        return;
    }
    if (m_p0.y() != m_p1.y())
        return;

    size.setHeight(1);
    srcRect.setHeight(1);
    srcRect.setY(0);
}

void BitmapImage::draw(GraphicsContext* ctxt, const FloatRect& destRect, const FloatRect& srcRect, ColorSpace styleColorSpace, CompositeOperator compositeOp)
{
    startAnimation();

    RetainPtr<CGImageRef> image = frameAtIndex(m_currentFrame);
    if (!image) // If it's too early we won't have an image yet.
        return;
    
    if (mayFillWithSolidColor()) {
        fillWithSolidColor(ctxt, destRect, solidColor(), styleColorSpace, compositeOp);
        return;
    }

    float currHeight = CGImageGetHeight(image.get());
    if (currHeight <= srcRect.y())
        return;

    CGContextRef context = ctxt->platformContext();
    ctxt->save();

    bool shouldUseSubimage = false;

    // If the source rect is a subportion of the image, then we compute an inflated destination rect that will hold the entire image
    // and then set a clip to the portion that we want to display.
    FloatRect adjustedDestRect = destRect;
    FloatSize selfSize = currentFrameSize();
    if (srcRect.size() != selfSize) {
        CGInterpolationQuality interpolationQuality = CGContextGetInterpolationQuality(context);
        // When the image is scaled using high-quality interpolation, we create a temporary CGImage
        // containing only the portion we want to display. We need to do this because high-quality
        // interpolation smoothes sharp edges, causing pixels from outside the source rect to bleed
        // into the destination rect. See <rdar://problem/6112909>.
        shouldUseSubimage = (interpolationQuality == kCGInterpolationHigh || interpolationQuality == kCGInterpolationDefault) && (srcRect.size() != destRect.size() || !ctxt->getCTM().isIdentityOrTranslationOrFlipped());
        float xScale = srcRect.width() / destRect.width();
        float yScale = srcRect.height() / destRect.height();
        if (shouldUseSubimage) {
            FloatRect subimageRect = srcRect;
            float leftPadding = srcRect.x() - floorf(srcRect.x());
            float topPadding = srcRect.y() - floorf(srcRect.y());

            subimageRect.move(-leftPadding, -topPadding);
            adjustedDestRect.move(-leftPadding / xScale, -topPadding / yScale);

            subimageRect.setWidth(ceilf(subimageRect.width() + leftPadding));
            adjustedDestRect.setWidth(subimageRect.width() / xScale);

            subimageRect.setHeight(ceilf(subimageRect.height() + topPadding));
            adjustedDestRect.setHeight(subimageRect.height() / yScale);

            image.adoptCF(CGImageCreateWithImageInRect(image.get(), subimageRect));
            if (currHeight < srcRect.bottom()) {
                ASSERT(CGImageGetHeight(image.get()) == currHeight - CGRectIntegral(srcRect).origin.y);
                adjustedDestRect.setHeight(CGImageGetHeight(image.get()) / yScale);
            }
        } else {
            adjustedDestRect.setLocation(FloatPoint(destRect.x() - srcRect.x() / xScale, destRect.y() - srcRect.y() / yScale));
            adjustedDestRect.setSize(FloatSize(selfSize.width() / xScale, selfSize.height() / yScale));
        }

        CGContextClipToRect(context, destRect);
    }

    // If the image is only partially loaded, then shrink the destination rect that we're drawing into accordingly.
    if (!shouldUseSubimage && currHeight < selfSize.height())
        adjustedDestRect.setHeight(adjustedDestRect.height() * currHeight / selfSize.height());

    ctxt->setCompositeOperation(compositeOp);

    // Flip the coords.
    CGContextScaleCTM(context, 1, -1);
    adjustedDestRect.setY(-adjustedDestRect.bottom());

    // Adjust the color space.
    image = imageWithColorSpace(image.get(), styleColorSpace);

    // Draw the image.
    CGContextDrawImage(context, adjustedDestRect, image.get());

    ctxt->restore();

    if (imageObserver())
        imageObserver()->didDraw(this);
}

void ShadowBlur::drawRectShadowWithTiling(GraphicsContext* graphicsContext, const FloatRect& shadowedRect, const RoundedIntRect::Radii& radii, const IntSize& shadowTemplateSize)
{
    const float roundedRadius = ceilf(m_blurRadius);
    const float twiceRadius = roundedRadius * 2;

    // Size of the tiling side.
    const int templateSideLength = 1;

    m_layerImage = ScratchBuffer::shared().getScratchBuffer(shadowTemplateSize);

    // Draw shadow into a new ImageBuffer.
    GraphicsContext* shadowContext = m_layerImage->context();
    shadowContext->save();
    
    shadowContext->clearRect(FloatRect(0, 0, shadowTemplateSize.width(), shadowTemplateSize.height()));

    // Draw the rectangle.
    FloatRect templateRect = FloatRect(roundedRadius, roundedRadius, shadowTemplateSize.width() - twiceRadius, shadowTemplateSize.height() - twiceRadius);
    Path path;
    path.addRoundedRect(templateRect, radii.topLeft(), radii.topRight(), radii.bottomLeft(), radii.bottomRight());

    shadowContext->setFillColor(Color(.0f, .0f, .0f, 1.f), ColorSpaceDeviceRGB);
    shadowContext->fillPath(path);

    // Blur the image.
    {
        IntRect blurRect(IntPoint(), shadowTemplateSize);
        RefPtr<ByteArray> layerData = m_layerImage->getUnmultipliedImageData(blurRect);
        blurLayerImage(layerData->data(), blurRect.size(), blurRect.width() * 4);
        m_layerImage->putUnmultipliedImageData(layerData.get(), blurRect.size(), blurRect, IntPoint());
    }

    // Mask the image with the shadow color.
    shadowContext->setCompositeOperation(CompositeSourceIn);
    shadowContext->setFillColor(m_color, m_colorSpace);
    shadowContext->fillRect(FloatRect(0, 0, shadowTemplateSize.width(), shadowTemplateSize.height()));
    
    shadowContext->restore();

    FloatRect shadowRect = shadowedRect;
    shadowRect.inflate(roundedRadius); // FIXME: duplicating code with calculateLayerBoundingRect.
    shadowRect.move(m_offset.width(), m_offset.height());

    // Fill the internal part of the shadow.
    shadowRect.inflate(-twiceRadius);
    if (!shadowRect.isEmpty()) {
        graphicsContext->save();
        
        path.clear();
        path.addRoundedRect(shadowRect, radii.topLeft(), radii.topRight(), radii.bottomLeft(), radii.bottomRight());

        graphicsContext->setFillColor(m_color, m_colorSpace);
        graphicsContext->fillPath(path);
        
        graphicsContext->restore();
    }
    shadowRect.inflate(twiceRadius);

    // Note that drawing the ImageBuffer is faster than creating a Image and drawing that,
    // because ImageBuffer::draw() knows that it doesn't have to copy the image bits.
        
    // Draw top side.
    FloatRect tileRect = FloatRect(twiceRadius + radii.topLeft().width(), 0, templateSideLength, twiceRadius);
    FloatRect destRect = tileRect;
    destRect.move(shadowRect.x(), shadowRect.y());
    destRect.setWidth(shadowRect.width() - radii.topLeft().width() - radii.topRight().width() - roundedRadius * 4);
    graphicsContext->drawImageBuffer(m_layerImage, ColorSpaceDeviceRGB, destRect, tileRect);

    // Draw the bottom side.
    tileRect = FloatRect(twiceRadius + radii.bottomLeft().width(), shadowTemplateSize.height() - twiceRadius, templateSideLength, twiceRadius);
    destRect = tileRect;
    destRect.move(shadowRect.x(), shadowRect.y() + twiceRadius + shadowedRect.height() - shadowTemplateSize.height());
    destRect.setWidth(shadowRect.width() - radii.bottomLeft().width() - radii.bottomRight().width() - roundedRadius * 4);
    graphicsContext->drawImageBuffer(m_layerImage, ColorSpaceDeviceRGB, destRect, tileRect);

    // Draw the right side.
    tileRect = FloatRect(shadowTemplateSize.width() - twiceRadius, twiceRadius + radii.topRight().height(), twiceRadius, templateSideLength);
    destRect = tileRect;
    destRect.move(shadowRect.x() + twiceRadius + shadowedRect.width() - shadowTemplateSize.width(), shadowRect.y());
    destRect.setHeight(shadowRect.height() - radii.topRight().height() - radii.bottomRight().height() - roundedRadius * 4);
    graphicsContext->drawImageBuffer(m_layerImage, ColorSpaceDeviceRGB, destRect, tileRect);

    // Draw the left side.
    tileRect = FloatRect(0, twiceRadius + radii.topLeft().height(), twiceRadius, templateSideLength);
    destRect = tileRect;
    destRect.move(shadowRect.x(), shadowRect.y());
    destRect.setHeight(shadowRect.height() - radii.topLeft().height() - radii.bottomLeft().height() - roundedRadius * 4);
    graphicsContext->drawImageBuffer(m_layerImage, ColorSpaceDeviceRGB, destRect, tileRect);

    // Draw the top left corner.
    tileRect = FloatRect(0, 0, twiceRadius + radii.topLeft().width(), twiceRadius + radii.topLeft().height());
    destRect = tileRect;
    destRect.move(shadowRect.x(), shadowRect.y());
    graphicsContext->drawImageBuffer(m_layerImage, ColorSpaceDeviceRGB, destRect, tileRect);

    // Draw the top right corner.
    tileRect = FloatRect(shadowTemplateSize.width() - twiceRadius - radii.topRight().width(), 0, twiceRadius + radii.topRight().width(),
                         twiceRadius + radii.topRight().height());
    destRect = tileRect;
    destRect.move(shadowRect.x() + shadowedRect.width() - shadowTemplateSize.width() + twiceRadius, shadowRect.y());
//.........这里部分代码省略.........

static Frame* createWindow(Frame* openerFrame, Frame* lookupFrame, const FrameLoadRequest& request, const WindowFeatures& features, bool& created)
{
    ASSERT(!features.dialog || request.frameName().isEmpty());

    if (!request.frameName().isEmpty() && request.frameName() != "_blank") {
        if (Frame* frame = lookupFrame->loader()->findFrameForNavigation(request.frameName(), openerFrame->document())) {
            if (request.frameName() != "_self") {
                if (Page* page = frame->page())
                    page->chrome().focus();
            }
            created = false;
            return frame;
        }
    }

    // Sandboxed frames cannot open new auxiliary browsing contexts.
    if (openerFrame->document()->isSandboxed(SandboxPopups)) {
        // FIXME: This message should be moved off the console once a solution to https://bugs.webkit.org/show_bug.cgi?id=103274 exists.
        openerFrame->document()->addConsoleMessage(SecurityMessageSource, ErrorMessageLevel, "Blocked opening '" + request.resourceRequest().url().elidedString() + "' in a new window because the request was made in a sandboxed frame whose 'allow-popups' permission is not set.");
        return 0;
    }

    // FIXME: Setting the referrer should be the caller's responsibility.
    FrameLoadRequest requestWithReferrer = request;
    String referrer = SecurityPolicy::generateReferrerHeader(openerFrame->document()->referrerPolicy(), request.resourceRequest().url(), openerFrame->loader()->outgoingReferrer());
    if (!referrer.isEmpty())
        requestWithReferrer.resourceRequest().setHTTPReferrer(referrer);
    FrameLoader::addHTTPOriginIfNeeded(requestWithReferrer.resourceRequest(), openerFrame->loader()->outgoingOrigin());

    if (openerFrame->settings() && !openerFrame->settings()->supportsMultipleWindows()) {
        created = false;
        return openerFrame->tree()->top();
    }

    Page* oldPage = openerFrame->page();
    if (!oldPage)
        return 0;

    NavigationAction action(requestWithReferrer.resourceRequest());
    Page* page = oldPage->chrome().client()->createWindow(openerFrame, requestWithReferrer, features, action);
    if (!page)
        return 0;

    Frame* frame = page->mainFrame();

    frame->loader()->forceSandboxFlags(openerFrame->document()->sandboxFlags());

    if (request.frameName() != "_blank")
        frame->tree()->setName(request.frameName());

    page->chrome().setWindowFeatures(features);

    // 'x' and 'y' specify the location of the window, while 'width' and 'height'
    // specify the size of the viewport. We can only resize the window, so adjust
    // for the difference between the window size and the viewport size.

    FloatRect windowRect = page->chrome().windowRect();
    FloatSize viewportSize = page->chrome().pageRect().size();

    if (features.xSet)
        windowRect.setX(features.x);
    if (features.ySet)
        windowRect.setY(features.y);
    if (features.widthSet)
        windowRect.setWidth(features.width + (windowRect.width() - viewportSize.width()));
    if (features.heightSet)
        windowRect.setHeight(features.height + (windowRect.height() - viewportSize.height()));

    // Ensure non-NaN values, minimum size as well as being within valid screen area.
    FloatRect newWindowRect = DOMWindow::adjustWindowRect(page, windowRect);

    page->chrome().setWindowRect(newWindowRect);
    page->chrome().show();

    created = true;
    return frame;
}

FloatRect TileController::computeTileCoverageRect(const FloatSize& newSize, const FloatRect& previousVisibleRect, const FloatRect& visibleRect, float contentsScale) const
{
    // If the page is not in a window (for example if it's in a background tab), we limit the tile coverage rect to the visible rect.
    if (!m_isInWindow)
        return visibleRect;

#if PLATFORM(IOS)
    // FIXME: unify the iOS and Mac code.
    UNUSED_PARAM(previousVisibleRect);
    
    if (m_tileCoverage == CoverageForVisibleArea || MemoryPressureHandler::singleton().isUnderMemoryPressure())
        return visibleRect;

    double horizontalMargin = tileSize().width() / contentsScale;
    double verticalMargin = tileSize().height() / contentsScale;

    double currentTime = monotonicallyIncreasingTime();
    double timeDelta = currentTime - m_velocity.lastUpdateTime;

    FloatRect futureRect = visibleRect;
    futureRect.setLocation(FloatPoint(
        futureRect.location().x() + timeDelta * m_velocity.horizontalVelocity,
        futureRect.location().y() + timeDelta * m_velocity.verticalVelocity));

    if (m_velocity.horizontalVelocity) {
        futureRect.setWidth(futureRect.width() + horizontalMargin);
        if (m_velocity.horizontalVelocity < 0)
            futureRect.setX(futureRect.x() - horizontalMargin);
    }

    if (m_velocity.verticalVelocity) {
        futureRect.setHeight(futureRect.height() + verticalMargin);
        if (m_velocity.verticalVelocity < 0)
            futureRect.setY(futureRect.y() - verticalMargin);
    }

    if (!m_velocity.horizontalVelocity && !m_velocity.verticalVelocity) {
        if (m_velocity.scaleChangeRate > 0)
            return visibleRect;
        futureRect.setWidth(futureRect.width() + horizontalMargin);
        futureRect.setHeight(futureRect.height() + verticalMargin);
        futureRect.setX(futureRect.x() - horizontalMargin / 2);
        futureRect.setY(futureRect.y() - verticalMargin / 2);
    }

    // Can't use m_tileCacheLayer->bounds() here, because the size of the underlying platform layer
    // hasn't been updated for the current commit.
    IntSize contentSize = expandedIntSize(newSize);
    if (futureRect.maxX() > contentSize.width())
        futureRect.setX(contentSize.width() - futureRect.width());
    if (futureRect.maxY() > contentSize.height())
        futureRect.setY(contentSize.height() - futureRect.height());
    if (futureRect.x() < 0)
        futureRect.setX(0);
    if (futureRect.y() < 0)
        futureRect.setY(0);

    return futureRect;
#else
    UNUSED_PARAM(contentsScale);

    // FIXME: look at how far the document can scroll in each dimension.
    float coverageHorizontalSize = visibleRect.width();
    float coverageVerticalSize = visibleRect.height();

    bool largeVisibleRectChange = !previousVisibleRect.isEmpty() && !visibleRect.intersects(previousVisibleRect);

    // Inflate the coverage rect so that it covers 2x of the visible width and 3x of the visible height.
    // These values were chosen because it's more common to have tall pages and to scroll vertically,
    // so we keep more tiles above and below the current area.

    if (m_tileCoverage & CoverageForHorizontalScrolling && !largeVisibleRectChange)
        coverageHorizontalSize *= 2;

    if (m_tileCoverage & CoverageForVerticalScrolling && !largeVisibleRectChange)
        coverageVerticalSize *= 3;

    coverageVerticalSize += topMarginHeight() + bottomMarginHeight();
    coverageHorizontalSize += leftMarginWidth() + rightMarginWidth();

    // Can't use m_tileCacheLayer->bounds() here, because the size of the underlying platform layer
    // hasn't been updated for the current commit.
    FloatRect coverageBounds = boundsForSize(newSize);
    float coverageLeft = visibleRect.x() - (coverageHorizontalSize - visibleRect.width()) / 2;
    coverageLeft = std::min(coverageLeft, coverageBounds.maxX() - coverageHorizontalSize);
    coverageLeft = std::max(coverageLeft, coverageBounds.x());

    float coverageTop = visibleRect.y() - (coverageVerticalSize - visibleRect.height()) / 2;
    coverageTop = std::min(coverageTop, coverageBounds.maxY() - coverageVerticalSize);
    coverageTop = std::max(coverageTop, coverageBounds.y());

    return FloatRect(coverageLeft, coverageTop, coverageHorizontalSize, coverageVerticalSize);
#endif
}

FloatRect RenderSVGResourceFilterPrimitive::determineFilterPrimitiveSubregion(FilterEffect* effect, SVGFilter* filter)
{
    FloatRect uniteRect;
    FloatRect subregionBoundingBox = effect->effectBoundaries();
    FloatRect subregion = subregionBoundingBox;

    if (effect->filterEffectType() != FilterEffectTypeTile) {
        // FETurbulence, FEImage and FEFlood don't have input effects, take the filter region as unite rect.
        if (unsigned numberOfInputEffects = effect->inputEffects().size()) {
            for (unsigned i = 0; i < numberOfInputEffects; ++i)
                uniteRect.unite(determineFilterPrimitiveSubregion(effect->inputEffect(i), filter));
        } else
            uniteRect = filter->filterRegionInUserSpace();
    } else {
        determineFilterPrimitiveSubregion(effect->inputEffect(0), filter);
        uniteRect = filter->filterRegionInUserSpace();
    }

    if (filter->effectBoundingBoxMode()) {
        subregion = uniteRect;
        // Avoid the calling of a virtual method several times.
        FloatRect targetBoundingBox = filter->targetBoundingBox();

        if (effect->hasX())
            subregion.setX(targetBoundingBox.x() + subregionBoundingBox.x() * targetBoundingBox.width());

        if (effect->hasY())
            subregion.setY(targetBoundingBox.y() + subregionBoundingBox.y() * targetBoundingBox.height());

        if (effect->hasWidth())
            subregion.setWidth(subregionBoundingBox.width() * targetBoundingBox.width());

        if (effect->hasHeight())
            subregion.setHeight(subregionBoundingBox.height() * targetBoundingBox.height());
    } else {
        if (!effect->hasX())
            subregion.setX(uniteRect.x());

        if (!effect->hasY())
            subregion.setY(uniteRect.y());

        if (!effect->hasWidth())
            subregion.setWidth(uniteRect.width());

        if (!effect->hasHeight())
            subregion.setHeight(uniteRect.height());
    }

    effect->setFilterPrimitiveSubregion(subregion);

    FloatRect absoluteSubregion = filter->mapLocalRectToAbsoluteRect(subregion);
    FloatSize filterResolution = filter->filterResolution();
    absoluteSubregion.scale(filterResolution.width(), filterResolution.height());

    // FEImage needs the unclipped subregion in absolute coordinates to determine the correct
    // destination rect in combination with preserveAspectRatio.
    if (effect->filterEffectType() == FilterEffectTypeImage)
        reinterpret_cast<FEImage*>(effect)->setAbsoluteSubregion(absoluteSubregion);

    // Clip every filter effect to the filter region.
    FloatRect absoluteScaledFilterRegion = filter->filterRegion();
    absoluteScaledFilterRegion.scale(filterResolution.width(), filterResolution.height());
    absoluteSubregion.intersect(absoluteScaledFilterRegion);

    effect->setMaxEffectRect(enclosingIntRect(absoluteSubregion));
    return subregion;
}

void TileController::adjustTileCoverageRect(FloatRect& coverageRect, const FloatSize& newSize, const FloatRect& previousVisibleRect, const FloatRect& visibleRect, float contentsScale) const
{
    // If the page is not in a window (for example if it's in a background tab), we limit the tile coverage rect to the visible rect.
    if (!m_isInWindow) {
        coverageRect = visibleRect;
        return;
    }

#if PLATFORM(IOS)
    // FIXME: unify the iOS and Mac code.
    UNUSED_PARAM(previousVisibleRect);
    
    if (m_tileCoverage == CoverageForVisibleArea || MemoryPressureHandler::singleton().isUnderMemoryPressure()) {
        coverageRect = visibleRect;
        return;
    }

    double horizontalMargin = kDefaultTileSize / contentsScale;
    double verticalMargin = kDefaultTileSize / contentsScale;

    double currentTime = monotonicallyIncreasingTime();
    double timeDelta = currentTime - m_velocity.lastUpdateTime;

    FloatRect futureRect = visibleRect;
    futureRect.setLocation(FloatPoint(
        futureRect.location().x() + timeDelta * m_velocity.horizontalVelocity,
        futureRect.location().y() + timeDelta * m_velocity.verticalVelocity));

    if (m_velocity.horizontalVelocity) {
        futureRect.setWidth(futureRect.width() + horizontalMargin);
        if (m_velocity.horizontalVelocity < 0)
            futureRect.setX(futureRect.x() - horizontalMargin);
    }

    if (m_velocity.verticalVelocity) {
        futureRect.setHeight(futureRect.height() + verticalMargin);
        if (m_velocity.verticalVelocity < 0)
            futureRect.setY(futureRect.y() - verticalMargin);
    }

    if (!m_velocity.horizontalVelocity && !m_velocity.verticalVelocity) {
        if (m_velocity.scaleChangeRate > 0) {
            coverageRect = visibleRect;
            return;
        }
        futureRect.setWidth(futureRect.width() + horizontalMargin);
        futureRect.setHeight(futureRect.height() + verticalMargin);
        futureRect.setX(futureRect.x() - horizontalMargin / 2);
        futureRect.setY(futureRect.y() - verticalMargin / 2);
    }

    // Can't use m_tileCacheLayer->bounds() here, because the size of the underlying platform layer
    // hasn't been updated for the current commit.
    IntSize contentSize = expandedIntSize(newSize);
    if (futureRect.maxX() > contentSize.width())
        futureRect.setX(contentSize.width() - futureRect.width());
    if (futureRect.maxY() > contentSize.height())
        futureRect.setY(contentSize.height() - futureRect.height());
    if (futureRect.x() < 0)
        futureRect.setX(0);
    if (futureRect.y() < 0)
        futureRect.setY(0);

    coverageRect.unite(futureRect);
    return;
#else
    UNUSED_PARAM(contentsScale);

    // FIXME: look at how far the document can scroll in each dimension.
    FloatSize coverageSize = visibleRect.size();

    bool largeVisibleRectChange = !previousVisibleRect.isEmpty() && !visibleRect.intersects(previousVisibleRect);

    // Inflate the coverage rect so that it covers 2x of the visible width and 3x of the visible height.
    // These values were chosen because it's more common to have tall pages and to scroll vertically,
    // so we keep more tiles above and below the current area.
    float widthScale = 1;
    float heightScale = 1;

    if (m_tileCoverage & CoverageForHorizontalScrolling && !largeVisibleRectChange)
        widthScale = 2;

    if (m_tileCoverage & CoverageForVerticalScrolling && !largeVisibleRectChange)
        heightScale = 3;
    
    coverageSize.scale(widthScale, heightScale);

    FloatRect coverageBounds = boundsForSize(newSize);
    
    FloatRect coverage = expandRectWithinRect(visibleRect, coverageSize, coverageBounds);
    LOG_WITH_STREAM(Scrolling, stream << "TileController::computeTileCoverageRect newSize=" << newSize << " mode " << m_tileCoverage << " expanded to " << coverageSize << " bounds with margin " << coverageBounds << " coverage " << coverage);
    coverageRect.unite(coverage);
#endif
}

void alignSelectionRectToDevicePixels(FloatRect& rect)
{
    float maxX = floorf(rect.maxX());
    rect.setX(floorf(rect.x()));
    rect.setWidth(roundf(maxX - rect.x()));
}

static LocalFrame* createWindow(LocalFrame& openerFrame, LocalFrame& lookupFrame, const FrameLoadRequest& request, const WindowFeatures& features, NavigationPolicy policy, ShouldSendReferrer shouldSendReferrer, bool& created)
{
    ASSERT(!features.dialog || request.frameName().isEmpty());

    if (!request.frameName().isEmpty() && request.frameName() != "_blank" && policy == NavigationPolicyIgnore) {
        if (LocalFrame* frame = lookupFrame.loader().findFrameForNavigation(request.frameName(), openerFrame.document())) {
            if (request.frameName() != "_self")
                frame->page()->focusController().setFocusedFrame(frame);
            created = false;
            return frame;
        }
    }

    // Sandboxed frames cannot open new auxiliary browsing contexts.
    if (openerFrame.document()->isSandboxed(SandboxPopups)) {
        // FIXME: This message should be moved off the console once a solution to https://bugs.webkit.org/show_bug.cgi?id=103274 exists.
        openerFrame.document()->addConsoleMessage(SecurityMessageSource, ErrorMessageLevel, "Blocked opening '" + request.resourceRequest().url().elidedString() + "' in a new window because the request was made in a sandboxed frame whose 'allow-popups' permission is not set.");
        return 0;
    }

    if (openerFrame.settings() && !openerFrame.settings()->supportsMultipleWindows()) {
        created = false;
        return openerFrame.tree().top();
    }

    Page* oldPage = openerFrame.page();
    if (!oldPage)
        return 0;

    Page* page = oldPage->chrome().client().createWindow(&openerFrame, request, features, policy, shouldSendReferrer);
    if (!page)
        return 0;
    FrameHost* host = &page->frameHost();

    ASSERT(page->mainFrame());
    LocalFrame& frame = *page->mainFrame();

    if (request.frameName() != "_blank")
        frame.tree().setName(request.frameName());

    host->chrome().setWindowFeatures(features);

    // 'x' and 'y' specify the location of the window, while 'width' and 'height'
    // specify the size of the viewport. We can only resize the window, so adjust
    // for the difference between the window size and the viewport size.

    FloatRect windowRect = host->chrome().windowRect();
    FloatSize viewportSize = host->chrome().pageRect().size();

    if (features.xSet)
        windowRect.setX(features.x);
    if (features.ySet)
        windowRect.setY(features.y);
    if (features.widthSet)
        windowRect.setWidth(features.width + (windowRect.width() - viewportSize.width()));
    if (features.heightSet)
        windowRect.setHeight(features.height + (windowRect.height() - viewportSize.height()));

    // Ensure non-NaN values, minimum size as well as being within valid screen area.
    FloatRect newWindowRect = DOMWindow::adjustWindowRect(frame, windowRect);

    host->chrome().setWindowRect(newWindowRect);
    host->chrome().show(policy);

    created = true;
    return &frame;
}

void RenderSVGImage::adjustRectsForAspectRatio(FloatRect& destRect, FloatRect& srcRect, SVGPreserveAspectRatio* aspectRatio)
{
    float origDestWidth = destRect.width();
    float origDestHeight = destRect.height();
    if (aspectRatio->meetOrSlice() == SVGPreserveAspectRatio::SVG_MEETORSLICE_MEET) {
        float widthToHeightMultiplier = srcRect.height() / srcRect.width();
        if (origDestHeight > (origDestWidth * widthToHeightMultiplier)) {
            destRect.setHeight(origDestWidth * widthToHeightMultiplier);
            switch(aspectRatio->align()) {
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMINYMID:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMID:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMID:
                    destRect.setY(destRect.y() + origDestHeight / 2.0f - destRect.height() / 2.0f);
                    break;
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMINYMAX:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMAX:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMAX:
                    destRect.setY(destRect.y() + origDestHeight - destRect.height());
                    break;
            }
        }
        if (origDestWidth > (origDestHeight / widthToHeightMultiplier)) {
            destRect.setWidth(origDestHeight / widthToHeightMultiplier);
            switch(aspectRatio->align()) {
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMIN:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMID:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMAX:
                    destRect.setX(destRect.x() + origDestWidth / 2.0f - destRect.width() / 2.0f);
                    break;
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMIN:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMID:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMAX:
                    destRect.setX(destRect.x() + origDestWidth - destRect.width());
                    break;
            }
        }
    } else if (aspectRatio->meetOrSlice() == SVGPreserveAspectRatio::SVG_MEETORSLICE_SLICE) {
        float widthToHeightMultiplier = srcRect.height() / srcRect.width();
        // if the destination height is less than the height of the image we'll be drawing
        if (origDestHeight < (origDestWidth * widthToHeightMultiplier)) {
            float destToSrcMultiplier = srcRect.width() / destRect.width();
            srcRect.setHeight(destRect.height() * destToSrcMultiplier);
            switch(aspectRatio->align()) {
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMINYMID:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMID:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMID:
                    srcRect.setY(destRect.y() + image()->height() / 2.0f - srcRect.height() / 2.0f);
                    break;
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMINYMAX:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMAX:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMAX:
                    srcRect.setY(destRect.y() + image()->height() - srcRect.height());
                    break;
            }
        }
        // if the destination width is less than the width of the image we'll be drawing
        if (origDestWidth < (origDestHeight / widthToHeightMultiplier)) {
            float destToSrcMultiplier = srcRect.height() / destRect.height();
            srcRect.setWidth(destRect.width() * destToSrcMultiplier);
            switch(aspectRatio->align()) {
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMIN:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMID:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMAX:
                    srcRect.setX(destRect.x() + image()->width() / 2.0f - srcRect.width() / 2.0f);
                    break;
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMIN:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMID:
                case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMAX:
                    srcRect.setX(destRect.x() + image()->width() - srcRect.width());
                    break;
            }
        }
    }
}

void Image::drawTiled(GraphicsContext& ctxt, const FloatRect& destRect, const FloatPoint& srcPoint, const FloatSize& scaledTileSize, const FloatSize& spacing, CompositeOperator op, BlendMode blendMode)
{    
    if (mayFillWithSolidColor()) {
        fillWithSolidColor(ctxt, destRect, solidColor(), op);
        return;
    }

    ASSERT(!isBitmapImage() || notSolidColor());

#if PLATFORM(IOS)
    FloatSize intrinsicTileSize = originalSize();
#else
    FloatSize intrinsicTileSize = size();
#endif
    if (hasRelativeWidth())
        intrinsicTileSize.setWidth(scaledTileSize.width());
    if (hasRelativeHeight())
        intrinsicTileSize.setHeight(scaledTileSize.height());

    FloatSize scale(scaledTileSize.width() / intrinsicTileSize.width(),
                    scaledTileSize.height() / intrinsicTileSize.height());

    FloatRect oneTileRect;
    FloatSize actualTileSize(scaledTileSize.width() + spacing.width(), scaledTileSize.height() + spacing.height());
    oneTileRect.setX(destRect.x() + fmodf(fmodf(-srcPoint.x(), actualTileSize.width()) - actualTileSize.width(), actualTileSize.width()));
    oneTileRect.setY(destRect.y() + fmodf(fmodf(-srcPoint.y(), actualTileSize.height()) - actualTileSize.height(), actualTileSize.height()));
    oneTileRect.setSize(scaledTileSize);
    
    // Check and see if a single draw of the image can cover the entire area we are supposed to tile.
    if (oneTileRect.contains(destRect) && !ctxt.drawLuminanceMask()) {
        FloatRect visibleSrcRect;
        visibleSrcRect.setX((destRect.x() - oneTileRect.x()) / scale.width());
        visibleSrcRect.setY((destRect.y() - oneTileRect.y()) / scale.height());
        visibleSrcRect.setWidth(destRect.width() / scale.width());
        visibleSrcRect.setHeight(destRect.height() / scale.height());
        draw(ctxt, destRect, visibleSrcRect, op, blendMode, ImageOrientationDescription());
        return;
    }

#if PLATFORM(IOS)
    // When using accelerated drawing on iOS, it's faster to stretch an image than to tile it.
    if (ctxt.isAcceleratedContext()) {
        if (size().width() == 1 && intersection(oneTileRect, destRect).height() == destRect.height()) {
            FloatRect visibleSrcRect;
            visibleSrcRect.setX(0);
            visibleSrcRect.setY((destRect.y() - oneTileRect.y()) / scale.height());
            visibleSrcRect.setWidth(1);
            visibleSrcRect.setHeight(destRect.height() / scale.height());
            draw(ctxt, destRect, visibleSrcRect, op, BlendModeNormal, ImageOrientationDescription());
            return;
        }
        if (size().height() == 1 && intersection(oneTileRect, destRect).width() == destRect.width()) {
            FloatRect visibleSrcRect;
            visibleSrcRect.setX((destRect.x() - oneTileRect.x()) / scale.width());
            visibleSrcRect.setY(0);
            visibleSrcRect.setWidth(destRect.width() / scale.width());
            visibleSrcRect.setHeight(1);
            draw(ctxt, destRect, visibleSrcRect, op, BlendModeNormal, ImageOrientationDescription());
            return;
        }
    }
#endif

    // Patterned images and gradients can use lots of memory for caching when the
    // tile size is large (<rdar://problem/4691859>, <rdar://problem/6239505>).
    // Memory consumption depends on the transformed tile size which can get
    // larger than the original tile if user zooms in enough.
#if PLATFORM(IOS)
    const float maxPatternTilePixels = 512 * 512;
#else
    const float maxPatternTilePixels = 2048 * 2048;
#endif
    FloatRect transformedTileSize = ctxt.getCTM().mapRect(FloatRect(FloatPoint(), scaledTileSize));
    float transformedTileSizePixels = transformedTileSize.width() * transformedTileSize.height();
    FloatRect currentTileRect = oneTileRect;
    if (transformedTileSizePixels > maxPatternTilePixels) {
        GraphicsContextStateSaver stateSaver(ctxt);
        ctxt.clip(destRect);

        currentTileRect.shiftYEdgeTo(destRect.y());
        float toY = currentTileRect.y();
        while (toY < destRect.maxY()) {
            currentTileRect.shiftXEdgeTo(destRect.x());
            float toX = currentTileRect.x();
            while (toX < destRect.maxX()) {
                FloatRect toRect(toX, toY, currentTileRect.width(), currentTileRect.height());
                FloatRect fromRect(toFloatPoint(currentTileRect.location() - oneTileRect.location()), currentTileRect.size());
                fromRect.scale(1 / scale.width(), 1 / scale.height());

                draw(ctxt, toRect, fromRect, op, BlendModeNormal, ImageOrientationDescription());
                toX += currentTileRect.width();
                currentTileRect.shiftXEdgeTo(oneTileRect.x());
            }
            toY += currentTileRect.height();
            currentTileRect.shiftYEdgeTo(oneTileRect.y());
        }
        return;
    }

    AffineTransform patternTransform = AffineTransform().scaleNonUniform(scale.width(), scale.height());
//.........这里部分代码省略.........

void SVGPreserveAspectRatio::transformRect(FloatRect& destRect, FloatRect& srcRect)
{
    if (m_align == SVG_PRESERVEASPECTRATIO_NONE)
        return;

    FloatSize imageSize = srcRect.size();
    float origDestWidth = destRect.width();
    float origDestHeight = destRect.height();
    switch (m_meetOrSlice) {
    case SVGPreserveAspectRatio::SVG_MEETORSLICE_UNKNOWN:
        break;
    case SVGPreserveAspectRatio::SVG_MEETORSLICE_MEET: {
        float widthToHeightMultiplier = srcRect.height() / srcRect.width();
        if (origDestHeight > origDestWidth * widthToHeightMultiplier) {
            destRect.setHeight(origDestWidth * widthToHeightMultiplier);
            switch (m_align) {
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMINYMID:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMID:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMID:
                destRect.setY(destRect.y() + origDestHeight / 2 - destRect.height() / 2);
                break;
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMINYMAX:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMAX:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMAX:
                destRect.setY(destRect.y() + origDestHeight - destRect.height());
                break;
            default:
                break;
            }
        }
        if (origDestWidth > origDestHeight / widthToHeightMultiplier) {
            destRect.setWidth(origDestHeight / widthToHeightMultiplier);
            switch (m_align) {
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMIN:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMID:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMAX:
                destRect.setX(destRect.x() + origDestWidth / 2 - destRect.width() / 2);
                break;
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMIN:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMID:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMAX:
                destRect.setX(destRect.x() + origDestWidth - destRect.width());
                break;
            default:
                break;
            }
        }
        break;
    }
    case SVGPreserveAspectRatio::SVG_MEETORSLICE_SLICE: {
        float widthToHeightMultiplier = srcRect.height() / srcRect.width();
        // if the destination height is less than the height of the image we'll be drawing
        if (origDestHeight < origDestWidth * widthToHeightMultiplier) {
            float destToSrcMultiplier = srcRect.width() / destRect.width();
            srcRect.setHeight(destRect.height() * destToSrcMultiplier);
            switch (m_align) {
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMINYMID:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMID:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMID:
                srcRect.setY(srcRect.y() + imageSize.height() / 2 - srcRect.height() / 2);
                break;
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMINYMAX:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMAX:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMAX:
                srcRect.setY(srcRect.y() + imageSize.height() - srcRect.height());
                break;
            default:
                break;
            }
        }
        // if the destination width is less than the width of the image we'll be drawing
        if (origDestWidth < origDestHeight / widthToHeightMultiplier) {
            float destToSrcMultiplier = srcRect.height() / destRect.height();
            srcRect.setWidth(destRect.width() * destToSrcMultiplier);
            switch (m_align) {
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMIN:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMID:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMAX:
                srcRect.setX(srcRect.x() + imageSize.width() / 2 - srcRect.width() / 2);
                break;
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMIN:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMID:
            case SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMAXYMAX:
                srcRect.setX(srcRect.x() + imageSize.width() - srcRect.width());
                break;
            default:
                break;
            }
        }
        break;
    }
    }
}