Home | History | Annotate | Download | only in rendering 
      1 /*
      2  * Copyright (C) 1999 Lars Knoll (knoll (at) kde.org)
      3  *           (C) 1999 Antti Koivisto (koivisto (at) kde.org)
      4  *           (C) 2000 Dirk Mueller (mueller (at) kde.org)
      5  *           (C) 2006 Allan Sandfeld Jensen (kde (at) carewolf.com)
      6  *           (C) 2006 Samuel Weinig (sam.weinig (at) gmail.com)
      7  * Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
      8  * Copyright (C) 2010 Google Inc. All rights reserved.
      9  * Copyright (C) Research In Motion Limited 2011-2012. All rights reserved.
     10  *
     11  * This library is free software; you can redistribute it and/or
     12  * modify it under the terms of the GNU Library General Public
     13  * License as published by the Free Software Foundation; either
     14  * version 2 of the License, or (at your option) any later version.
     15  *
     16  * This library is distributed in the hope that it will be useful,
     17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
     18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     19  * Library General Public License for more details.
     20  *
     21  * You should have received a copy of the GNU Library General Public License
     22  * along with this library; see the file COPYING.LIB.  If not, write to
     23  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
     24  * Boston, MA 02110-1301, USA.
     25  *
     26  */
     27 
     28 #include "config.h"
     29 #include "core/rendering/RenderImage.h"
     30 
     31 #include "HTMLNames.h"
     32 #include "core/editing/FrameSelection.h"
     33 #include "core/html/HTMLAreaElement.h"
     34 #include "core/html/HTMLImageElement.h"
     35 #include "core/html/HTMLInputElement.h"
     36 #include "core/html/HTMLMapElement.h"
     37 #include "core/loader/cache/ImageResource.h"
     38 #include "core/page/Frame.h"
     39 #include "core/page/Page.h"
     40 #include "core/platform/graphics/Font.h"
     41 #include "core/platform/graphics/FontCache.h"
     42 #include "core/platform/graphics/GraphicsContext.h"
     43 #include "core/platform/graphics/GraphicsContextStateSaver.h"
     44 #include "core/rendering/HitTestResult.h"
     45 #include "core/rendering/PaintInfo.h"
     46 #include "core/rendering/RenderView.h"
     47 #include "core/svg/graphics/SVGImage.h"
     48 #include "wtf/UnusedParam.h"
     49 
     50 using namespace std;
     51 
     52 namespace WebCore {
     53 
     54 using namespace HTMLNames;
     55 
     56 RenderImage::RenderImage(Element* element)
     57     : RenderReplaced(element, IntSize())
     58     , m_needsToSetSizeForAltText(false)
     59     , m_didIncrementVisuallyNonEmptyPixelCount(false)
     60     , m_isGeneratedContent(false)
     61 {
     62     updateAltText();
     63 }
     64 
     65 RenderImage* RenderImage::createAnonymous(Document* document)
     66 {
     67     RenderImage* image = new RenderImage(0);
     68     image->setDocumentForAnonymous(document);
     69     return image;
     70 }
     71 
     72 RenderImage::~RenderImage()
     73 {
     74     ASSERT(m_imageResource);
     75     m_imageResource->shutdown();
     76 }
     77 
     78 void RenderImage::setImageResource(PassOwnPtr<RenderImageResource> imageResource)
     79 {
     80     ASSERT(!m_imageResource);
     81     m_imageResource = imageResource;
     82     m_imageResource->initialize(this);
     83 }
     84 
     85 // If we'll be displaying either alt text or an image, add some padding.
     86 static const unsigned short paddingWidth = 4;
     87 static const unsigned short paddingHeight = 4;
     88 
     89 // Alt text is restricted to this maximum size, in pixels.  These are
     90 // signed integers because they are compared with other signed values.
     91 static const float maxAltTextWidth = 1024;
     92 static const int maxAltTextHeight = 256;
     93 
     94 IntSize RenderImage::imageSizeForError(ImageResource* newImage) const
     95 {
     96     ASSERT_ARG(newImage, newImage);
     97     ASSERT_ARG(newImage, newImage->imageForRenderer(this));
     98 
     99     IntSize imageSize;
    100     if (newImage->willPaintBrokenImage()) {
    101         float deviceScaleFactor = WebCore::deviceScaleFactor(frame());
    102         pair<Image*, float> brokenImageAndImageScaleFactor = newImage->brokenImage(deviceScaleFactor);
    103         imageSize = brokenImageAndImageScaleFactor.first->size();
    104         imageSize.scale(1 / brokenImageAndImageScaleFactor.second);
    105     } else
    106         imageSize = newImage->imageForRenderer(this)->size();
    107 
    108     // imageSize() returns 0 for the error image. We need the true size of the
    109     // error image, so we have to get it by grabbing image() directly.
    110     return IntSize(paddingWidth + imageSize.width() * style()->effectiveZoom(), paddingHeight + imageSize.height() * style()->effectiveZoom());
    111 }
    112 
    113 // Sets the image height and width to fit the alt text.  Returns true if the
    114 // image size changed.
    115 bool RenderImage::setImageSizeForAltText(ImageResource* newImage /* = 0 */)
    116 {
    117     IntSize imageSize;
    118     if (newImage && newImage->imageForRenderer(this))
    119         imageSize = imageSizeForError(newImage);
    120     else if (!m_altText.isEmpty() || newImage) {
    121         // If we'll be displaying either text or an image, add a little padding.
    122         imageSize = IntSize(paddingWidth, paddingHeight);
    123     }
    124 
    125     // we have an alt and the user meant it (its not a text we invented)
    126     if (!m_altText.isEmpty()) {
    127         FontCachePurgePreventer fontCachePurgePreventer;
    128 
    129         const Font& font = style()->font();
    130         IntSize paddedTextSize(paddingWidth + min(ceilf(font.width(RenderBlock::constructTextRun(this, font, m_altText, style()))), maxAltTextWidth), paddingHeight + min(font.fontMetrics().height(), maxAltTextHeight));
    131         imageSize = imageSize.expandedTo(paddedTextSize);
    132     }
    133 
    134     if (imageSize == intrinsicSize())
    135         return false;
    136 
    137     setIntrinsicSize(imageSize);
    138     return true;
    139 }
    140 
    141 void RenderImage::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
    142 {
    143     RenderReplaced::styleDidChange(diff, oldStyle);
    144     if (m_needsToSetSizeForAltText) {
    145         if (!m_altText.isEmpty() && setImageSizeForAltText(m_imageResource->cachedImage()))
    146             imageDimensionsChanged(true /* imageSizeChanged */);
    147         m_needsToSetSizeForAltText = false;
    148     }
    149 }
    150 
    151 void RenderImage::imageChanged(WrappedImagePtr newImage, const IntRect* rect)
    152 {
    153     if (documentBeingDestroyed())
    154         return;
    155 
    156     if (hasBoxDecorations() || hasMask())
    157         RenderReplaced::imageChanged(newImage, rect);
    158 
    159     if (!m_imageResource)
    160         return;
    161 
    162     if (newImage != m_imageResource->imagePtr())
    163         return;
    164 
    165     if (!m_didIncrementVisuallyNonEmptyPixelCount) {
    166         // At a zoom level of 1 the image is guaranteed to have an integer size.
    167         view()->frameView()->incrementVisuallyNonEmptyPixelCount(flooredIntSize(m_imageResource->imageSize(1.0f)));
    168         m_didIncrementVisuallyNonEmptyPixelCount = true;
    169     }
    170 
    171     bool imageSizeChanged = false;
    172 
    173     // Set image dimensions, taking into account the size of the alt text.
    174     if (m_imageResource->errorOccurred() || !newImage) {
    175         if (!m_altText.isEmpty() && document()->hasPendingStyleRecalc()) {
    176             ASSERT(node());
    177             if (node()) {
    178                 m_needsToSetSizeForAltText = true;
    179                 node()->setNeedsStyleRecalc(LocalStyleChange, StyleChangeFromRenderer);
    180             }
    181             return;
    182         }
    183         imageSizeChanged = setImageSizeForAltText(m_imageResource->cachedImage());
    184     }
    185 
    186     imageDimensionsChanged(imageSizeChanged, rect);
    187 }
    188 
    189 bool RenderImage::updateIntrinsicSizeIfNeeded(const LayoutSize& newSize, bool imageSizeChanged)
    190 {
    191     if (newSize == intrinsicSize() && !imageSizeChanged)
    192         return false;
    193     if (m_imageResource->errorOccurred() || !m_imageResource->hasImage())
    194         return imageSizeChanged;
    195     setIntrinsicSize(newSize);
    196     return true;
    197 }
    198 
    199 void RenderImage::imageDimensionsChanged(bool imageSizeChanged, const IntRect* rect)
    200 {
    201     bool intrinsicSizeChanged = updateIntrinsicSizeIfNeeded(m_imageResource->imageSize(style()->effectiveZoom()), imageSizeChanged);
    202 
    203     // In the case of generated image content using :before/:after/content, we might not be
    204     // in the render tree yet. In that case, we just need to update our intrinsic size.
    205     // layout() will be called after we are inserted in the tree which will take care of
    206     // what we are doing here.
    207     if (!containingBlock())
    208         return;
    209 
    210     bool shouldRepaint = true;
    211     if (intrinsicSizeChanged) {
    212         if (!preferredLogicalWidthsDirty())
    213             setPreferredLogicalWidthsDirty(true);
    214 
    215         bool hasOverrideSize = hasOverrideHeight() || hasOverrideWidth();
    216         if (!hasOverrideSize && !imageSizeChanged) {
    217             LogicalExtentComputedValues computedValues;
    218             computeLogicalWidthInRegion(computedValues);
    219             LayoutUnit newWidth = computedValues.m_extent;
    220             computeLogicalHeight(height(), 0, computedValues);
    221             LayoutUnit newHeight = computedValues.m_extent;
    222 
    223             imageSizeChanged = width() != newWidth || height() != newHeight;
    224         }
    225 
    226         // FIXME: We only need to recompute the containing block's preferred size
    227         // if the containing block's size depends on the image's size (i.e., the container uses shrink-to-fit sizing).
    228         // There's no easy way to detect that shrink-to-fit is needed, always force a layout.
    229         bool containingBlockNeedsToRecomputePreferredSize =
    230             style()->logicalWidth().isPercent()
    231             || style()->logicalMaxWidth().isPercent()
    232             || style()->logicalMinWidth().isPercent();
    233 
    234         if (imageSizeChanged || hasOverrideSize || containingBlockNeedsToRecomputePreferredSize) {
    235             shouldRepaint = false;
    236             if (!selfNeedsLayout())
    237                 setNeedsLayout();
    238         }
    239     }
    240 
    241     if (shouldRepaint) {
    242         LayoutRect repaintRect;
    243         if (rect) {
    244             // The image changed rect is in source image coordinates (pre-zooming),
    245             // so map from the bounds of the image to the contentsBox.
    246             repaintRect = enclosingIntRect(mapRect(*rect, FloatRect(FloatPoint(), m_imageResource->imageSize(1.0f)), contentBoxRect()));
    247             // Guard against too-large changed rects.
    248             repaintRect.intersect(contentBoxRect());
    249         } else
    250             repaintRect = contentBoxRect();
    251 
    252         repaintRectangle(repaintRect);
    253 
    254         // Tell any potential compositing layers that the image needs updating.
    255         contentChanged(ImageChanged);
    256     }
    257 }
    258 
    259 void RenderImage::notifyFinished(Resource* newImage)
    260 {
    261     if (!m_imageResource)
    262         return;
    263 
    264     if (documentBeingDestroyed())
    265         return;
    266 
    267     invalidateBackgroundObscurationStatus();
    268 
    269     if (newImage == m_imageResource->cachedImage()) {
    270         // tell any potential compositing layers
    271         // that the image is done and they can reference it directly.
    272         contentChanged(ImageChanged);
    273     }
    274 }
    275 
    276 void RenderImage::paintReplaced(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
    277 {
    278     LayoutUnit cWidth = contentWidth();
    279     LayoutUnit cHeight = contentHeight();
    280     LayoutUnit leftBorder = borderLeft();
    281     LayoutUnit topBorder = borderTop();
    282     LayoutUnit leftPad = paddingLeft();
    283     LayoutUnit topPad = paddingTop();
    284 
    285     GraphicsContext* context = paintInfo.context;
    286 
    287     Page* page = 0;
    288     if (Frame* frame = this->frame())
    289         page = frame->page();
    290 
    291     if (!m_imageResource->hasImage() || m_imageResource->errorOccurred()) {
    292         if (paintInfo.phase == PaintPhaseSelection)
    293             return;
    294 
    295         if (page && paintInfo.phase == PaintPhaseForeground)
    296             page->addRelevantUnpaintedObject(this, visualOverflowRect());
    297 
    298         if (cWidth > 2 && cHeight > 2) {
    299             const int borderWidth = 1;
    300 
    301             // Draw an outline rect where the image should be.
    302             context->setStrokeStyle(SolidStroke);
    303             context->setStrokeColor(Color::lightGray);
    304             context->setFillColor(Color::transparent);
    305             context->drawRect(pixelSnappedIntRect(LayoutRect(paintOffset.x() + leftBorder + leftPad, paintOffset.y() + topBorder + topPad, cWidth, cHeight)));
    306 
    307             bool errorPictureDrawn = false;
    308             LayoutSize imageOffset;
    309             // When calculating the usable dimensions, exclude the pixels of
    310             // the ouline rect so the error image/alt text doesn't draw on it.
    311             LayoutUnit usableWidth = cWidth - 2 * borderWidth;
    312             LayoutUnit usableHeight = cHeight - 2 * borderWidth;
    313 
    314             RefPtr<Image> image = m_imageResource->image();
    315 
    316             if (m_imageResource->errorOccurred() && !image->isNull() && usableWidth >= image->width() && usableHeight >= image->height()) {
    317                 float deviceScaleFactor = WebCore::deviceScaleFactor(frame());
    318                 // Call brokenImage() explicitly to ensure we get the broken image icon at the appropriate resolution.
    319                 pair<Image*, float> brokenImageAndImageScaleFactor = m_imageResource->cachedImage()->brokenImage(deviceScaleFactor);
    320                 image = brokenImageAndImageScaleFactor.first;
    321                 IntSize imageSize = image->size();
    322                 imageSize.scale(1 / brokenImageAndImageScaleFactor.second);
    323                 // Center the error image, accounting for border and padding.
    324                 LayoutUnit centerX = (usableWidth - imageSize.width()) / 2;
    325                 if (centerX < 0)
    326                     centerX = 0;
    327                 LayoutUnit centerY = (usableHeight - imageSize.height()) / 2;
    328                 if (centerY < 0)
    329                     centerY = 0;
    330                 imageOffset = LayoutSize(leftBorder + leftPad + centerX + borderWidth, topBorder + topPad + centerY + borderWidth);
    331                 context->drawImage(image.get(), pixelSnappedIntRect(LayoutRect(paintOffset + imageOffset, imageSize)), CompositeSourceOver, shouldRespectImageOrientation());
    332                 errorPictureDrawn = true;
    333             }
    334 
    335             if (!m_altText.isEmpty()) {
    336                 String text = document()->displayStringModifiedByEncoding(m_altText);
    337                 const Font& font = style()->font();
    338                 const FontMetrics& fontMetrics = font.fontMetrics();
    339                 LayoutUnit ascent = fontMetrics.ascent();
    340                 LayoutPoint textRectOrigin = paintOffset;
    341                 textRectOrigin.move(leftBorder + leftPad + (paddingWidth / 2) - borderWidth, topBorder + topPad + (paddingHeight / 2) - borderWidth);
    342                 LayoutPoint textOrigin(textRectOrigin.x(), textRectOrigin.y() + ascent);
    343 
    344                 // Only draw the alt text if it'll fit within the content box,
    345                 // and only if it fits above the error image.
    346                 TextRun textRun = RenderBlock::constructTextRun(this, font, text, style());
    347                 LayoutUnit textWidth = font.width(textRun);
    348                 TextRunPaintInfo textRunPaintInfo(textRun);
    349                 textRunPaintInfo.bounds = FloatRect(textRectOrigin, FloatSize(textWidth, fontMetrics.height()));
    350                 context->setFillColor(resolveColor(CSSPropertyColor));
    351                 if (errorPictureDrawn) {
    352                     if (usableWidth >= textWidth && fontMetrics.height() <= imageOffset.height())
    353                         context->drawText(font, textRunPaintInfo, textOrigin);
    354                 } else if (usableWidth >= textWidth && usableHeight >= fontMetrics.height())
    355                     context->drawText(font, textRunPaintInfo, textOrigin);
    356             }
    357         }
    358     } else if (m_imageResource->hasImage() && cWidth > 0 && cHeight > 0) {
    359         RefPtr<Image> img = m_imageResource->image(cWidth, cHeight);
    360         if (!img || img->isNull()) {
    361             if (page && paintInfo.phase == PaintPhaseForeground)
    362                 page->addRelevantUnpaintedObject(this, visualOverflowRect());
    363             return;
    364         }
    365 
    366         LayoutSize contentSize(cWidth, cHeight);
    367         LayoutPoint contentLocation = paintOffset;
    368         contentLocation.move(leftBorder + leftPad, topBorder + topPad);
    369         paintIntoRect(context, LayoutRect(contentLocation, contentSize));
    370 
    371         if (cachedImage() && page && paintInfo.phase == PaintPhaseForeground) {
    372             // For now, count images as unpainted if they are still progressively loading. We may want
    373             // to refine this in the future to account for the portion of the image that has painted.
    374             if (cachedImage()->isLoading())
    375                 page->addRelevantUnpaintedObject(this, LayoutRect(contentLocation, contentSize));
    376             else
    377                 page->addRelevantRepaintedObject(this, LayoutRect(contentLocation, contentSize));
    378         }
    379     }
    380 }
    381 
    382 void RenderImage::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
    383 {
    384     RenderReplaced::paint(paintInfo, paintOffset);
    385 
    386     if (paintInfo.phase == PaintPhaseOutline)
    387         paintAreaElementFocusRing(paintInfo);
    388 }
    389 
    390 void RenderImage::paintAreaElementFocusRing(PaintInfo& paintInfo)
    391 {
    392     Document* document = this->document();
    393 
    394     if (document->printing() || !document->frame()->selection()->isFocusedAndActive())
    395         return;
    396 
    397     if (paintInfo.context->paintingDisabled() && !paintInfo.context->updatingControlTints())
    398         return;
    399 
    400     Element* focusedElement = document->focusedElement();
    401     if (!focusedElement || !isHTMLAreaElement(focusedElement))
    402         return;
    403 
    404     HTMLAreaElement* areaElement = toHTMLAreaElement(focusedElement);
    405     if (areaElement->imageElement() != node())
    406         return;
    407 
    408     // Even if the theme handles focus ring drawing for entire elements, it won't do it for
    409     // an area within an image, so we don't call RenderTheme::supportsFocusRing here.
    410 
    411     Path path = areaElement->computePath(this);
    412     if (path.isEmpty())
    413         return;
    414 
    415     RenderStyle* areaElementStyle = areaElement->computedStyle();
    416     unsigned short outlineWidth = areaElementStyle->outlineWidth();
    417     if (!outlineWidth)
    418         return;
    419 
    420     // FIXME: Clip path instead of context when Skia pathops is ready.
    421     // https://crbug.com/251206
    422     GraphicsContextStateSaver savedContext(*paintInfo.context);
    423     paintInfo.context->clip(absoluteContentBox());
    424     paintInfo.context->drawFocusRing(path, outlineWidth,
    425         areaElementStyle->outlineOffset(),
    426         resolveColor(areaElementStyle, CSSPropertyOutlineColor));
    427 }
    428 
    429 void RenderImage::areaElementFocusChanged(HTMLAreaElement* areaElement)
    430 {
    431     ASSERT(areaElement->imageElement() == node());
    432 
    433     Path path = areaElement->computePath(this);
    434     if (path.isEmpty())
    435         return;
    436 
    437     RenderStyle* areaElementStyle = areaElement->computedStyle();
    438     unsigned short outlineWidth = areaElementStyle->outlineWidth();
    439 
    440     IntRect repaintRect = enclosingIntRect(path.boundingRect());
    441     repaintRect.moveBy(-absoluteContentBox().location());
    442     repaintRect.inflate(outlineWidth);
    443 
    444     repaintRectangle(repaintRect);
    445 }
    446 
    447 void RenderImage::paintIntoRect(GraphicsContext* context, const LayoutRect& rect)
    448 {
    449     IntRect alignedRect = pixelSnappedIntRect(rect);
    450     if (!m_imageResource->hasImage() || m_imageResource->errorOccurred() || alignedRect.width() <= 0 || alignedRect.height() <= 0)
    451         return;
    452 
    453     RefPtr<Image> img = m_imageResource->image(alignedRect.width(), alignedRect.height());
    454     if (!img || img->isNull())
    455         return;
    456 
    457     HTMLImageElement* imageElt = (node() && node()->hasTagName(imgTag)) ? toHTMLImageElement(node()) : 0;
    458     CompositeOperator compositeOperator = imageElt ? imageElt->compositeOperator() : CompositeSourceOver;
    459     Image* image = m_imageResource->image().get();
    460     bool useLowQualityScaling = shouldPaintAtLowQuality(context, image, image, alignedRect.size());
    461     context->drawImage(m_imageResource->image(alignedRect.width(), alignedRect.height()).get(), alignedRect, compositeOperator, shouldRespectImageOrientation(), useLowQualityScaling);
    462 }
    463 
    464 bool RenderImage::boxShadowShouldBeAppliedToBackground(BackgroundBleedAvoidance bleedAvoidance, InlineFlowBox*) const
    465 {
    466     if (!RenderBoxModelObject::boxShadowShouldBeAppliedToBackground(bleedAvoidance))
    467         return false;
    468 
    469     return !const_cast<RenderImage*>(this)->backgroundIsKnownToBeObscured();
    470 }
    471 
    472 bool RenderImage::foregroundIsKnownToBeOpaqueInRect(const LayoutRect& localRect, unsigned maxDepthToTest) const
    473 {
    474     UNUSED_PARAM(maxDepthToTest);
    475     if (!m_imageResource->hasImage() || m_imageResource->errorOccurred())
    476         return false;
    477     if (m_imageResource->cachedImage() && !m_imageResource->cachedImage()->isLoaded())
    478         return false;
    479     if (!contentBoxRect().contains(localRect))
    480         return false;
    481     EFillBox backgroundClip = style()->backgroundClip();
    482     // Background paints under borders.
    483     if (backgroundClip == BorderFillBox && style()->hasBorder() && !borderObscuresBackground())
    484         return false;
    485     // Background shows in padding area.
    486     if ((backgroundClip == BorderFillBox || backgroundClip == PaddingFillBox) && style()->hasPadding())
    487         return false;
    488     // Check for image with alpha.
    489     return m_imageResource->cachedImage() && m_imageResource->cachedImage()->currentFrameKnownToBeOpaque(this);
    490 }
    491 
    492 bool RenderImage::computeBackgroundIsKnownToBeObscured()
    493 {
    494     if (!hasBackground())
    495         return false;
    496     return foregroundIsKnownToBeOpaqueInRect(backgroundPaintedExtent(), 0);
    497 }
    498 
    499 LayoutUnit RenderImage::minimumReplacedHeight() const
    500 {
    501     return m_imageResource->errorOccurred() ? intrinsicSize().height() : LayoutUnit();
    502 }
    503 
    504 HTMLMapElement* RenderImage::imageMap() const
    505 {
    506     HTMLImageElement* i = node() && node()->hasTagName(imgTag) ? toHTMLImageElement(node()) : 0;
    507     return i ? i->treeScope()->getImageMap(i->fastGetAttribute(usemapAttr)) : 0;
    508 }
    509 
    510 bool RenderImage::nodeAtPoint(const HitTestRequest& request, HitTestResult& result, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, HitTestAction hitTestAction)
    511 {
    512     HitTestResult tempResult(result.hitTestLocation());
    513     bool inside = RenderReplaced::nodeAtPoint(request, tempResult, locationInContainer, accumulatedOffset, hitTestAction);
    514 
    515     if (tempResult.innerNode() && node()) {
    516         if (HTMLMapElement* map = imageMap()) {
    517             LayoutRect contentBox = contentBoxRect();
    518             float scaleFactor = 1 / style()->effectiveZoom();
    519             LayoutPoint mapLocation = locationInContainer.point() - toLayoutSize(accumulatedOffset) - locationOffset() - toLayoutSize(contentBox.location());
    520             mapLocation.scale(scaleFactor, scaleFactor);
    521 
    522             if (map->mapMouseEvent(mapLocation, contentBox.size(), tempResult))
    523                 tempResult.setInnerNonSharedNode(node());
    524         }
    525     }
    526 
    527     if (!inside && result.isRectBasedTest())
    528         result.append(tempResult);
    529     if (inside)
    530         result = tempResult;
    531     return inside;
    532 }
    533 
    534 void RenderImage::updateAltText()
    535 {
    536     if (!node())
    537         return;
    538 
    539     if (node()->hasTagName(inputTag))
    540         m_altText = toHTMLInputElement(node())->altText();
    541     else if (node()->hasTagName(imgTag))
    542         m_altText = toHTMLImageElement(node())->altText();
    543 }
    544 
    545 void RenderImage::layout()
    546 {
    547     StackStats::LayoutCheckPoint layoutCheckPoint;
    548     RenderReplaced::layout();
    549 
    550     // Propagate container size to image resource.
    551     IntSize containerSize(contentWidth(), contentHeight());
    552     if (!containerSize.isEmpty())
    553         m_imageResource->setContainerSizeForRenderer(containerSize);
    554 }
    555 
    556 void RenderImage::computeIntrinsicRatioInformation(FloatSize& intrinsicSize, double& intrinsicRatio, bool& isPercentageIntrinsicSize) const
    557 {
    558     RenderReplaced::computeIntrinsicRatioInformation(intrinsicSize, intrinsicRatio, isPercentageIntrinsicSize);
    559 
    560     // Our intrinsicSize is empty if we're rendering generated images with relative width/height. Figure out the right intrinsic size to use.
    561     if (intrinsicSize.isEmpty() && (m_imageResource->imageHasRelativeWidth() || m_imageResource->imageHasRelativeHeight())) {
    562         RenderObject* containingBlock = isOutOfFlowPositioned() ? container() : this->containingBlock();
    563         if (containingBlock->isBox()) {
    564             RenderBox* box = toRenderBox(containingBlock);
    565             intrinsicSize.setWidth(box->availableLogicalWidth());
    566             intrinsicSize.setHeight(box->availableLogicalHeight(IncludeMarginBorderPadding));
    567         }
    568     }
    569     // Don't compute an intrinsic ratio to preserve historical WebKit behavior if we're painting alt text and/or a broken image.
    570     if (m_imageResource && m_imageResource->errorOccurred()) {
    571         intrinsicRatio = 1;
    572         return;
    573     }
    574 }
    575 
    576 bool RenderImage::needsPreferredWidthsRecalculation() const
    577 {
    578     if (RenderReplaced::needsPreferredWidthsRecalculation())
    579         return true;
    580     return embeddedContentBox();
    581 }
    582 
    583 RenderBox* RenderImage::embeddedContentBox() const
    584 {
    585     if (!m_imageResource)
    586         return 0;
    587 
    588     ImageResource* cachedImage = m_imageResource->cachedImage();
    589     if (cachedImage && cachedImage->image() && cachedImage->image()->isSVGImage())
    590         return static_cast<SVGImage*>(cachedImage->image())->embeddedContentBox();
    591 
    592     return 0;
    593 }
    594 
    595 } // namespace WebCore
    596