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      1 /*
      2  * Copyright (C) 2006 Samuel Weinig (sam.weinig (at) gmail.com)
      3  * Copyright (C) 2004, 2005, 2006 Apple Computer, Inc.  All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      8  * 1. Redistributions of source code must retain the above copyright
      9  *    notice, this list of conditions and the following disclaimer.
     10  * 2. Redistributions in binary form must reproduce the above copyright
     11  *    notice, this list of conditions and the following disclaimer in the
     12  *    documentation and/or other materials provided with the distribution.
     13  *
     14  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
     15  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     17  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
     18  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     19  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     20  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     21  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
     22  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     24  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     25  */
     26 
     27 #include "config.h"
     28 #include "platform/graphics/Image.h"
     29 
     30 #include "platform/Length.h"
     31 #include "platform/MIMETypeRegistry.h"
     32 #include "platform/SharedBuffer.h"
     33 #include "platform/TraceEvent.h"
     34 #include "platform/geometry/FloatPoint.h"
     35 #include "platform/geometry/FloatRect.h"
     36 #include "platform/geometry/FloatSize.h"
     37 #include "platform/graphics/BitmapImage.h"
     38 #include "platform/graphics/GraphicsContext.h"
     39 #include "platform/graphics/GraphicsContextStateSaver.h"
     40 #include "public/platform/Platform.h"
     41 #include "public/platform/WebData.h"
     42 #include "wtf/MainThread.h"
     43 #include "wtf/StdLibExtras.h"
     44 
     45 #include <math.h>
     46 
     47 namespace WebCore {
     48 
     49 Image::Image(ImageObserver* observer)
     50     : m_imageObserver(observer)
     51 {
     52 }
     53 
     54 Image::~Image()
     55 {
     56 }
     57 
     58 Image* Image::nullImage()
     59 {
     60     ASSERT(isMainThread());
     61     DEFINE_STATIC_REF(Image, nullImage, (BitmapImage::create()));
     62     return nullImage;
     63 }
     64 
     65 PassRefPtr<Image> Image::loadPlatformResource(const char *name)
     66 {
     67     const blink::WebData& resource = blink::Platform::current()->loadResource(name);
     68     if (resource.isEmpty())
     69         return Image::nullImage();
     70 
     71     RefPtr<Image> image = BitmapImage::create();
     72     image->setData(resource, true);
     73     return image.release();
     74 }
     75 
     76 bool Image::supportsType(const String& type)
     77 {
     78     return MIMETypeRegistry::isSupportedImageResourceMIMEType(type);
     79 }
     80 
     81 bool Image::setData(PassRefPtr<SharedBuffer> data, bool allDataReceived)
     82 {
     83     m_encodedImageData = data;
     84     if (!m_encodedImageData.get())
     85         return true;
     86 
     87     int length = m_encodedImageData->size();
     88     if (!length)
     89         return true;
     90 
     91     return dataChanged(allDataReceived);
     92 }
     93 
     94 void Image::fillWithSolidColor(GraphicsContext* ctxt, const FloatRect& dstRect, const Color& color, CompositeOperator op)
     95 {
     96     if (!color.alpha())
     97         return;
     98 
     99     CompositeOperator previousOperator = ctxt->compositeOperation();
    100     ctxt->setCompositeOperation(!color.hasAlpha() && op == CompositeSourceOver ? CompositeCopy : op);
    101     ctxt->fillRect(dstRect, color);
    102     ctxt->setCompositeOperation(previousOperator);
    103 }
    104 
    105 FloatRect Image::adjustForNegativeSize(const FloatRect& rect)
    106 {
    107     FloatRect norm = rect;
    108     if (norm.width() < 0) {
    109         norm.setX(norm.x() + norm.width());
    110         norm.setWidth(-norm.width());
    111     }
    112     if (norm.height() < 0) {
    113         norm.setY(norm.y() + norm.height());
    114         norm.setHeight(-norm.height());
    115     }
    116     return norm;
    117 }
    118 
    119 void Image::draw(GraphicsContext* ctx, const FloatRect& dstRect, const FloatRect& srcRect, CompositeOperator op, blink::WebBlendMode blendMode, RespectImageOrientationEnum)
    120 {
    121     draw(ctx, dstRect, srcRect, op, blendMode);
    122 }
    123 
    124 void Image::drawTiled(GraphicsContext* ctxt, const FloatRect& destRect, const FloatPoint& srcPoint, const FloatSize& scaledTileSize, CompositeOperator op, blink::WebBlendMode blendMode, const IntSize& repeatSpacing)
    125 {
    126     if (mayFillWithSolidColor()) {
    127         fillWithSolidColor(ctxt, destRect, solidColor(), op);
    128         return;
    129     }
    130 
    131     // See <https://webkit.org/b/59043>.
    132     ASSERT(!isBitmapImage() || notSolidColor());
    133 
    134     FloatSize intrinsicTileSize = size();
    135     if (hasRelativeWidth())
    136         intrinsicTileSize.setWidth(scaledTileSize.width());
    137     if (hasRelativeHeight())
    138         intrinsicTileSize.setHeight(scaledTileSize.height());
    139 
    140     FloatSize scale(scaledTileSize.width() / intrinsicTileSize.width(),
    141                     scaledTileSize.height() / intrinsicTileSize.height());
    142 
    143     FloatSize actualTileSize(scaledTileSize.width() + repeatSpacing.width(), scaledTileSize.height() + repeatSpacing.height());
    144     FloatRect oneTileRect;
    145     oneTileRect.setX(destRect.x() + fmodf(fmodf(-srcPoint.x(), actualTileSize.width()) - actualTileSize.width(), actualTileSize.width()));
    146     oneTileRect.setY(destRect.y() + fmodf(fmodf(-srcPoint.y(), actualTileSize.height()) - actualTileSize.height(), actualTileSize.height()));
    147     oneTileRect.setSize(scaledTileSize);
    148 
    149     // Check and see if a single draw of the image can cover the entire area we are supposed to tile.
    150     if (oneTileRect.contains(destRect)) {
    151         FloatRect visibleSrcRect;
    152         visibleSrcRect.setX((destRect.x() - oneTileRect.x()) / scale.width());
    153         visibleSrcRect.setY((destRect.y() - oneTileRect.y()) / scale.height());
    154         visibleSrcRect.setWidth(destRect.width() / scale.width());
    155         visibleSrcRect.setHeight(destRect.height() / scale.height());
    156         draw(ctxt, destRect, visibleSrcRect, op, blendMode);
    157         return;
    158     }
    159 
    160     FloatRect tileRect(FloatPoint(), intrinsicTileSize);
    161     drawPattern(ctxt, tileRect, scale, oneTileRect.location(), op, destRect, blendMode, repeatSpacing);
    162 
    163     startAnimation();
    164 }
    165 
    166 // FIXME: Merge with the other drawTiled eventually, since we need a combination of both for some things.
    167 void Image::drawTiled(GraphicsContext* ctxt, const FloatRect& dstRect, const FloatRect& srcRect,
    168     const FloatSize& providedTileScaleFactor, TileRule hRule, TileRule vRule, CompositeOperator op)
    169 {
    170     if (mayFillWithSolidColor()) {
    171         fillWithSolidColor(ctxt, dstRect, solidColor(), op);
    172         return;
    173     }
    174 
    175     // FIXME: We do not support 'space' yet. For now just map it to 'repeat'.
    176     if (hRule == SpaceTile)
    177         hRule = RepeatTile;
    178     if (vRule == SpaceTile)
    179         vRule = RepeatTile;
    180 
    181     // FIXME: if this code is used for background-repeat: round (in addition to
    182     // border-image-repeat), then add logic to deal with the background-size: auto
    183     // special case. The aspect ratio should be maintained in this case.
    184     FloatSize tileScaleFactor = providedTileScaleFactor;
    185     bool useLowInterpolationQuality = false;
    186     if (hRule == RoundTile) {
    187         float hRepetitions = std::max(1.0f, roundf(dstRect.width() / (tileScaleFactor.width() * srcRect.width())));
    188         tileScaleFactor.setWidth(dstRect.width() / (srcRect.width() * hRepetitions));
    189     }
    190     if (vRule == RoundTile) {
    191         float vRepetitions = std::max(1.0f, roundf(dstRect.height() / (tileScaleFactor.height() * srcRect.height())));
    192         tileScaleFactor.setHeight(dstRect.height() / (srcRect.height() * vRepetitions));
    193     }
    194     if (hRule == RoundTile || vRule == RoundTile) {
    195         // High interpolation quality rounds the scaled tile to an integer size (see Image::drawPattern).
    196         // To avoid causing a visual problem, linear interpolation must be used instead.
    197         // FIXME: Allow using high-quality interpolation in this case, too.
    198         useLowInterpolationQuality = true;
    199     }
    200 
    201     // We want to construct the phase such that the pattern is centered (when stretch is not
    202     // set for a particular rule).
    203     float hPhase = tileScaleFactor.width() * srcRect.x();
    204     float vPhase = tileScaleFactor.height() * srcRect.y();
    205     float scaledTileWidth = tileScaleFactor.width() * srcRect.width();
    206     float scaledTileHeight = tileScaleFactor.height() * srcRect.height();
    207     if (hRule == Image::RepeatTile)
    208         hPhase -= (dstRect.width() - scaledTileWidth) / 2;
    209     if (vRule == Image::RepeatTile)
    210         vPhase -= (dstRect.height() - scaledTileHeight) / 2;
    211     FloatPoint patternPhase(dstRect.x() - hPhase, dstRect.y() - vPhase);
    212 
    213     if (useLowInterpolationQuality) {
    214         InterpolationQuality previousInterpolationQuality = ctxt->imageInterpolationQuality();
    215         ctxt->setImageInterpolationQuality(InterpolationLow);
    216         drawPattern(ctxt, srcRect, tileScaleFactor, patternPhase, op, dstRect);
    217         ctxt->setImageInterpolationQuality(previousInterpolationQuality);
    218     } else {
    219         drawPattern(ctxt, srcRect, tileScaleFactor, patternPhase, op, dstRect);
    220     }
    221 
    222     startAnimation();
    223 }
    224 
    225 void Image::drawPattern(GraphicsContext* context, const FloatRect& floatSrcRect, const FloatSize& scale,
    226     const FloatPoint& phase, CompositeOperator compositeOp, const FloatRect& destRect, blink::WebBlendMode blendMode, const IntSize& repeatSpacing)
    227 {
    228     TRACE_EVENT0("skia", "Image::drawPattern");
    229     if (RefPtr<NativeImageSkia> bitmap = nativeImageForCurrentFrame())
    230         bitmap->drawPattern(context, adjustForNegativeSize(floatSrcRect), scale, phase, compositeOp, destRect, blendMode, repeatSpacing);
    231 }
    232 
    233 void Image::computeIntrinsicDimensions(Length& intrinsicWidth, Length& intrinsicHeight, FloatSize& intrinsicRatio)
    234 {
    235     intrinsicRatio = size();
    236     intrinsicWidth = Length(intrinsicRatio.width(), Fixed);
    237     intrinsicHeight = Length(intrinsicRatio.height(), Fixed);
    238 }
    239 
    240 }
    241