third_party/WebKit/Source/core/layout/svg/LayoutSVGResourceMasker.cpp

   1 /*
   2  * Copyright (C) Research In Motion Limited 2009-2010. All rights reserved.
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Library General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public License
  15  * along with this library; see the file COPYING.LIB.  If not, write to
  16  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17  * Boston, MA 02110-1301, USA.
  18  */
  19
  20 #include "config.h"
  21 #include "core/layout/svg/LayoutSVGResourceMasker.h"
  22
  23 #include "core/dom/ElementTraversal.h"
  24 #include "core/layout/svg/SVGLayoutSupport.h"
  25 #include "core/paint/SVGPaintContext.h"
  26 #include "core/svg/SVGElement.h"
  27 #include "platform/graphics/paint/SkPictureBuilder.h"
  28 #include "platform/transforms/AffineTransform.h"
  29 #include "third_party/skia/include/core/SkPicture.h"
  30
  31 namespace blink {
  32
  33 LayoutSVGResourceMasker::LayoutSVGResourceMasker(SVGMaskElement* node)
  34     : LayoutSVGResourceContainer(node)
  35 {
  36 }
  37
  38 LayoutSVGResourceMasker::~LayoutSVGResourceMasker()
  39 {
  40 }
  41
  42 void LayoutSVGResourceMasker::removeAllClientsFromCache(bool markForInvalidation)
  43 {
  44     m_maskContentPicture.clear();
  45     m_maskContentBoundaries = FloatRect();
  46     markAllClientsForInvalidation(markForInvalidation ? LayoutAndBoundariesInvalidation : ParentOnlyInvalidation);
  47 }
  48
  49 void LayoutSVGResourceMasker::removeClientFromCache(LayoutObject* client, bool markForInvalidation)
  50 {
  51     ASSERT(client);
  52     markClientForInvalidation(client, markForInvalidation ? BoundariesInvalidation : ParentOnlyInvalidation);
  53 }
  54
  55 PassRefPtr<const SkPicture> LayoutSVGResourceMasker::createContentPicture(AffineTransform& contentTransformation, const FloatRect& targetBoundingBox,
  56     GraphicsContext* context)
  57 {
  58     SVGUnitTypes::SVGUnitType contentUnits = toSVGMaskElement(element())->maskContentUnits()->currentValue()->enumValue();
  59     if (contentUnits == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
  60         contentTransformation.translate(targetBoundingBox.x(), targetBoundingBox.y());
  61         contentTransformation.scaleNonUniform(targetBoundingBox.width(), targetBoundingBox.height());
  62     }
  63
  64     if (m_maskContentPicture)
  65         return m_maskContentPicture;
  66
  67     SubtreeContentTransformScope contentTransformScope(contentTransformation);
  68
  69     // Using strokeBoundingBox (instead of paintInvalidationRectInLocalCoordinates) to avoid the intersection
  70     // with local clips/mask, which may yield incorrect results when mixing objectBoundingBox and
  71     // userSpaceOnUse units (http://crbug.com/294900).
  72     FloatRect bounds = strokeBoundingBox();
  73
  74     SkPictureBuilder pictureBuilder(bounds, nullptr, context);
  75
  76     ColorFilter maskContentFilter = style()->svgStyle().colorInterpolation() == CI_LINEARRGB
  77         ? ColorFilterSRGBToLinearRGB : ColorFilterNone;
  78     pictureBuilder.context().setColorFilter(maskContentFilter);
  79
  80     for (SVGElement* childElement = Traversal<SVGElement>::firstChild(*element()); childElement; childElement = Traversal<SVGElement>::nextSibling(*childElement)) {
  81         LayoutObject* layoutObject = childElement->layoutObject();
  82         if (!layoutObject)
  83             continue;
  84         const ComputedStyle* style = layoutObject->style();
  85         if (!style || style->display() == NONE || style->visibility() != VISIBLE)
  86             continue;
  87
  88         SVGPaintContext::paintSubtree(&pictureBuilder.context(), layoutObject);
  89     }
  90
  91     m_maskContentPicture = pictureBuilder.endRecording();
  92     return m_maskContentPicture;
  93 }
  94
  95 void LayoutSVGResourceMasker::calculateMaskContentPaintInvalidationRect()
  96 {
  97     for (SVGElement* childElement = Traversal<SVGElement>::firstChild(*element()); childElement; childElement = Traversal<SVGElement>::nextSibling(*childElement)) {
  98         LayoutObject* layoutObject = childElement->layoutObject();
  99         if (!layoutObject)
 100             continue;
 101         const ComputedStyle* style = layoutObject->style();
 102         if (!style || style->display() == NONE || style->visibility() != VISIBLE)
 103             continue;
 104         m_maskContentBoundaries.unite(layoutObject->localToParentTransform().mapRect(layoutObject->paintInvalidationRectInLocalCoordinates()));
 105     }
 106 }
 107
 108 FloatRect LayoutSVGResourceMasker::resourceBoundingBox(const LayoutObject* object)
 109 {
 110     SVGMaskElement* maskElement = toSVGMaskElement(element());
 111     ASSERT(maskElement);
 112
 113     FloatRect objectBoundingBox = object->objectBoundingBox();
 114     FloatRect maskBoundaries = SVGLengthContext::resolveRectangle<SVGMaskElement>(maskElement, maskElement->maskUnits()->currentValue()->enumValue(), objectBoundingBox);
 115
 116     // Resource was not layouted yet. Give back clipping rect of the mask.
 117     if (selfNeedsLayout())
 118         return maskBoundaries;
 119
 120     if (m_maskContentBoundaries.isEmpty())
 121         calculateMaskContentPaintInvalidationRect();
 122
 123     FloatRect maskRect = m_maskContentBoundaries;
 124     if (maskElement->maskContentUnits()->currentValue()->value() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
 125         AffineTransform transform;
 126         transform.translate(objectBoundingBox.x(), objectBoundingBox.y());
 127         transform.scaleNonUniform(objectBoundingBox.width(), objectBoundingBox.height());
 128         maskRect = transform.mapRect(maskRect);
 129     }
 130
 131     maskRect.intersect(maskBoundaries);
 132     return maskRect;
 133 }
 134
 135 }