src/third_party/WebKit/Source/core/svg/graphics/filters/SVGFEImage.cpp

   1 /*
   2  * Copyright (C) 2004, 2005, 2006, 2007 Nikolas Zimmermann <zimmermann@kde.org>
   3  * Copyright (C) 2004, 2005 Rob Buis <buis@kde.org>
   4  * Copyright (C) 2005 Eric Seidel <eric@webkit.org>
   5  * Copyright (C) 2010 Dirk Schulze <krit@webkit.org>
   6  * Copyright (C) 2013 Google Inc. All rights reserved.
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Library General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Library General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Library General Public License
  19  * along with this library; see the file COPYING.LIB.  If not, write to
  20  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  21  * Boston, MA 02110-1301, USA.
  22  */
  23
  24 #include "config.h"
  25
  26 #include "core/svg/graphics/filters/SVGFEImage.h"
  27
  28 #include "SkBitmapSource.h"
  29 #include "SkPictureImageFilter.h"
  30 #include "core/rendering/RenderObject.h"
  31 #include "core/rendering/svg/SVGRenderingContext.h"
  32 #include "core/svg/SVGElement.h"
  33 #include "core/svg/SVGURIReference.h"
  34 #include "platform/graphics/DisplayList.h"
  35 #include "platform/graphics/GraphicsContext.h"
  36 #include "platform/graphics/filters/Filter.h"
  37 #include "platform/graphics/filters/SkiaImageFilterBuilder.h"
  38 #include "platform/text/TextStream.h"
  39 #include "platform/transforms/AffineTransform.h"
  40
  41 namespace blink {
  42
  43 FEImage::FEImage(Filter* filter, PassRefPtr<Image> image, PassRefPtr<SVGPreserveAspectRatio> preserveAspectRatio)
  44     : FilterEffect(filter)
  45     , m_image(image)
  46     , m_treeScope(0)
  47     , m_preserveAspectRatio(preserveAspectRatio)
  48 {
  49 }
  50
  51 FEImage::FEImage(Filter* filter, TreeScope& treeScope, const String& href, PassRefPtr<SVGPreserveAspectRatio> preserveAspectRatio)
  52     : FilterEffect(filter)
  53     , m_treeScope(&treeScope)
  54     , m_href(href)
  55     , m_preserveAspectRatio(preserveAspectRatio)
  56 {
  57 }
  58
  59 PassRefPtr<FEImage> FEImage::createWithImage(Filter* filter, PassRefPtr<Image> image, PassRefPtr<SVGPreserveAspectRatio> preserveAspectRatio)
  60 {
  61     return adoptRef(new FEImage(filter, image, preserveAspectRatio));
  62 }
  63
  64 PassRefPtr<FEImage> FEImage::createWithIRIReference(Filter* filter, TreeScope& treeScope, const String& href, PassRefPtr<SVGPreserveAspectRatio> preserveAspectRatio)
  65 {
  66     return adoptRef(new FEImage(filter, treeScope, href, preserveAspectRatio));
  67 }
  68
  69 static FloatRect getRendererRepaintRect(RenderObject* renderer)
  70 {
  71     return renderer->localToParentTransform().mapRect(
  72         renderer->paintInvalidationRectInLocalCoordinates());
  73 }
  74
  75 AffineTransform makeMapBetweenRects(const FloatRect& source, const FloatRect& dest)
  76 {
  77     AffineTransform transform;
  78     transform.translate(dest.x() - source.x(), dest.y() - source.y());
  79     transform.scale(dest.width() / source.width(), dest.height() / source.height());
  80     return transform;
  81 }
  82
  83 FloatRect FEImage::determineAbsolutePaintRect(const FloatRect& originalRequestedRect)
  84 {
  85     RenderObject* renderer = referencedRenderer();
  86     if (!m_image && !renderer)
  87         return FloatRect();
  88
  89     FloatRect requestedRect = originalRequestedRect;
  90     if (clipsToBounds())
  91         requestedRect.intersect(maxEffectRect());
  92
  93     FloatRect destRect = filter()->mapLocalRectToAbsoluteRect(filterPrimitiveSubregion());
  94     FloatRect srcRect;
  95     if (renderer) {
  96         srcRect = getRendererRepaintRect(renderer);
  97         SVGElement* contextNode = toSVGElement(renderer->node());
  98
  99         if (contextNode->hasRelativeLengths()) {
 100             // FIXME: This fixes relative lengths but breaks non-relative ones (see crbug/260709).
 101             SVGLengthContext lengthContext(contextNode);
 102             FloatSize viewportSize;
 103             if (lengthContext.determineViewport(viewportSize)) {
 104                 srcRect = makeMapBetweenRects(FloatRect(FloatPoint(), viewportSize), destRect).mapRect(srcRect);
 105             }
 106         } else {
 107             srcRect = filter()->mapLocalRectToAbsoluteRect(srcRect);
 108             srcRect.move(destRect.x(), destRect.y());
 109         }
 110         destRect.intersect(srcRect);
 111     } else {
 112         srcRect = FloatRect(FloatPoint(), m_image->size());
 113         m_preserveAspectRatio->transformRect(destRect, srcRect);
 114     }
 115
 116     destRect.intersect(requestedRect);
 117     addAbsolutePaintRect(destRect);
 118     return destRect;
 119 }
 120
 121 RenderObject* FEImage::referencedRenderer() const
 122 {
 123     if (!m_treeScope)
 124         return 0;
 125     Element* hrefElement = SVGURIReference::targetElementFromIRIString(m_href, *m_treeScope);
 126     if (!hrefElement || !hrefElement->isSVGElement())
 127         return 0;
 128     return hrefElement->renderer();
 129 }
 130
 131 TextStream& FEImage::externalRepresentation(TextStream& ts, int indent) const
 132 {
 133     IntSize imageSize;
 134     if (m_image)
 135         imageSize = m_image->size();
 136     else if (RenderObject* renderer = referencedRenderer())
 137         imageSize = enclosingIntRect(getRendererRepaintRect(renderer)).size();
 138     writeIndent(ts, indent);
 139     ts << "[feImage";
 140     FilterEffect::externalRepresentation(ts);
 141     ts << " image-size=\"" << imageSize.width() << "x" << imageSize.height() << "\"]\n";
 142     // FIXME: should this dump also object returned by SVGFEImage::image() ?
 143     return ts;
 144 }
 145
 146 PassRefPtr<SkImageFilter> FEImage::createImageFilterForRenderer(RenderObject* renderer, SkiaImageFilterBuilder* builder)
 147 {
 148     FloatRect dstRect = filterPrimitiveSubregion();
 149
 150     AffineTransform transform;
 151     SVGElement* contextNode = toSVGElement(renderer->node());
 152
 153     if (contextNode->hasRelativeLengths()) {
 154         SVGLengthContext lengthContext(contextNode);
 155         FloatSize viewportSize;
 156
 157         // If we're referencing an element with percentage units, eg. <rect with="30%"> those values were resolved against the viewport.
 158         // Build up a transformation that maps from the viewport space to the filter primitive subregion.
 159         if (lengthContext.determineViewport(viewportSize))
 160             transform = makeMapBetweenRects(FloatRect(FloatPoint(), viewportSize), dstRect);
 161     } else {
 162         transform.translate(dstRect.x(), dstRect.y());
 163     }
 164
 165     GraphicsContext* context = builder->context();
 166     if (!context)
 167         return adoptRef(SkBitmapSource::Create(SkBitmap()));
 168     FloatRect bounds(FloatPoint(), dstRect.size());
 169     context->save();
 170     context->beginRecording(bounds);
 171     context->concatCTM(transform);
 172     SVGRenderingContext::renderSubtree(context, renderer);
 173     RefPtr<DisplayList> displayList = context->endRecording();
 174     context->restore();
 175     RefPtr<SkImageFilter> result = adoptRef(SkPictureImageFilter::Create(displayList->picture().get(), dstRect));
 176     return result.release();
 177 }
 178
 179 PassRefPtr<SkImageFilter> FEImage::createImageFilter(SkiaImageFilterBuilder* builder)
 180 {
 181     RenderObject* renderer = referencedRenderer();
 182     if (!m_image && !renderer)
 183         return adoptRef(SkBitmapSource::Create(SkBitmap()));
 184
 185     setOperatingColorSpace(ColorSpaceDeviceRGB);
 186
 187     if (renderer)
 188         return createImageFilterForRenderer(renderer, builder);
 189
 190     FloatRect srcRect = FloatRect(FloatPoint(), m_image->size());
 191     FloatRect dstRect = filterPrimitiveSubregion();
 192
 193     // FIXME: CSS image filters currently do not seem to set filter primitive
 194     // subregion correctly if unspecified. So default to srcRect size if so.
 195     if (dstRect.isEmpty())
 196         dstRect = srcRect;
 197
 198     m_preserveAspectRatio->transformRect(dstRect, srcRect);
 199
 200     if (!m_image->nativeImageForCurrentFrame())
 201         return adoptRef(SkBitmapSource::Create(SkBitmap()));
 202
 203     RefPtr<SkImageFilter> result = adoptRef(SkBitmapSource::Create(m_image->nativeImageForCurrentFrame()->bitmap(), srcRect, dstRect));
 204     return result.release();
 205 }
 206
 207 } // namespace blink