src/third_party/WebKit/Source/core/svg/SVGLinearGradientElement.cpp

   1 /*
   2  * Copyright (C) 2004, 2005, 2006, 2008 Nikolas Zimmermann <zimmermann@kde.org>
   3  * Copyright (C) 2004, 2005, 2006, 2007 Rob Buis <buis@kde.org>
   4  * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
   5  * Copyright (C) 2008 Dirk Schulze <krit@webkit.org>
   6  * Copyright (C) Research In Motion Limited 2010. 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/SVGLinearGradientElement.h"
  27
  28 #include "core/rendering/svg/RenderSVGResourceLinearGradient.h"
  29 #include "core/svg/LinearGradientAttributes.h"
  30 #include "core/svg/SVGElementInstance.h"
  31 #include "core/svg/SVGLength.h"
  32 #include "core/svg/SVGTransformList.h"
  33
  34 namespace WebCore {
  35
  36 // Animated property definitions
  37 BEGIN_REGISTER_ANIMATED_PROPERTIES(SVGLinearGradientElement)
  38     REGISTER_PARENT_ANIMATED_PROPERTIES(SVGGradientElement)
  39 END_REGISTER_ANIMATED_PROPERTIES
  40
  41 inline SVGLinearGradientElement::SVGLinearGradientElement(Document& document)
  42     : SVGGradientElement(SVGNames::linearGradientTag, document)
  43     , m_x1(SVGAnimatedLength::create(this, SVGNames::x1Attr, SVGLength::create(LengthModeWidth)))
  44     , m_y1(SVGAnimatedLength::create(this, SVGNames::y1Attr, SVGLength::create(LengthModeHeight)))
  45     , m_x2(SVGAnimatedLength::create(this, SVGNames::x2Attr, SVGLength::create(LengthModeWidth)))
  46     , m_y2(SVGAnimatedLength::create(this, SVGNames::y2Attr, SVGLength::create(LengthModeHeight)))
  47 {
  48     ScriptWrappable::init(this);
  49
  50     // Spec: If the x2 attribute is not specified, the effect is as if a value of "100%" were specified.
  51     m_x2->setDefaultValueAsString("100%");
  52
  53     addToPropertyMap(m_x1);
  54     addToPropertyMap(m_y1);
  55     addToPropertyMap(m_x2);
  56     addToPropertyMap(m_y2);
  57     registerAnimatedPropertiesForSVGLinearGradientElement();
  58 }
  59
  60 PassRefPtr<SVGLinearGradientElement> SVGLinearGradientElement::create(Document& document)
  61 {
  62     return adoptRef(new SVGLinearGradientElement(document));
  63 }
  64
  65 bool SVGLinearGradientElement::isSupportedAttribute(const QualifiedName& attrName)
  66 {
  67     DEFINE_STATIC_LOCAL(HashSet<QualifiedName>, supportedAttributes, ());
  68     if (supportedAttributes.isEmpty()) {
  69         supportedAttributes.add(SVGNames::x1Attr);
  70         supportedAttributes.add(SVGNames::x2Attr);
  71         supportedAttributes.add(SVGNames::y1Attr);
  72         supportedAttributes.add(SVGNames::y2Attr);
  73     }
  74     return supportedAttributes.contains<SVGAttributeHashTranslator>(attrName);
  75 }
  76
  77 void SVGLinearGradientElement::parseAttribute(const QualifiedName& name, const AtomicString& value)
  78 {
  79     SVGParsingError parseError = NoError;
  80
  81     if (!isSupportedAttribute(name))
  82         SVGGradientElement::parseAttribute(name, value);
  83     else if (name == SVGNames::x1Attr)
  84         m_x1->setBaseValueAsString(value, AllowNegativeLengths, parseError);
  85     else if (name == SVGNames::y1Attr)
  86         m_y1->setBaseValueAsString(value, AllowNegativeLengths, parseError);
  87     else if (name == SVGNames::x2Attr)
  88         m_x2->setBaseValueAsString(value, AllowNegativeLengths, parseError);
  89     else if (name == SVGNames::y2Attr)
  90         m_y2->setBaseValueAsString(value, AllowNegativeLengths, parseError);
  91     else
  92         ASSERT_NOT_REACHED();
  93
  94     reportAttributeParsingError(parseError, name, value);
  95 }
  96
  97 void SVGLinearGradientElement::svgAttributeChanged(const QualifiedName& attrName)
  98 {
  99     if (!isSupportedAttribute(attrName)) {
 100         SVGGradientElement::svgAttributeChanged(attrName);
 101         return;
 102     }
 103
 104     SVGElementInstance::InvalidationGuard invalidationGuard(this);
 105
 106     updateRelativeLengthsInformation();
 107
 108     RenderSVGResourceContainer* renderer = toRenderSVGResourceContainer(this->renderer());
 109     if (renderer)
 110         renderer->invalidateCacheAndMarkForLayout();
 111 }
 112
 113 RenderObject* SVGLinearGradientElement::createRenderer(RenderStyle*)
 114 {
 115     return new RenderSVGResourceLinearGradient(this);
 116 }
 117
 118 static void setGradientAttributes(SVGGradientElement* element, LinearGradientAttributes& attributes, bool isLinear = true)
 119 {
 120     if (!attributes.hasSpreadMethod() && element->spreadMethodSpecified())
 121         attributes.setSpreadMethod(element->spreadMethodCurrentValue());
 122
 123     if (!attributes.hasGradientUnits() && element->gradientUnitsSpecified())
 124         attributes.setGradientUnits(element->gradientUnitsCurrentValue());
 125
 126     if (!attributes.hasGradientTransform() && element->gradientTransformSpecified()) {
 127         AffineTransform transform;
 128         element->gradientTransformCurrentValue().concatenate(transform);
 129         attributes.setGradientTransform(transform);
 130     }
 131
 132     if (!attributes.hasStops()) {
 133         const Vector<Gradient::ColorStop>& stops(element->buildStops());
 134         if (!stops.isEmpty())
 135             attributes.setStops(stops);
 136     }
 137
 138     if (isLinear) {
 139         SVGLinearGradientElement* linear = toSVGLinearGradientElement(element);
 140
 141         if (!attributes.hasX1() && linear->x1()->isSpecified())
 142             attributes.setX1(linear->x1()->currentValue());
 143
 144         if (!attributes.hasY1() && linear->y1()->isSpecified())
 145             attributes.setY1(linear->y1()->currentValue());
 146
 147         if (!attributes.hasX2() && linear->x2()->isSpecified())
 148             attributes.setX2(linear->x2()->currentValue());
 149
 150         if (!attributes.hasY2() && linear->y2()->isSpecified())
 151             attributes.setY2(linear->y2()->currentValue());
 152     }
 153 }
 154
 155 bool SVGLinearGradientElement::collectGradientAttributes(LinearGradientAttributes& attributes)
 156 {
 157     if (!renderer())
 158         return false;
 159
 160     HashSet<SVGGradientElement*> processedGradients;
 161     SVGGradientElement* current = this;
 162
 163     setGradientAttributes(current, attributes);
 164     processedGradients.add(current);
 165
 166     while (true) {
 167         // Respect xlink:href, take attributes from referenced element
 168         Node* refNode = SVGURIReference::targetElementFromIRIString(current->hrefCurrentValue(), document());
 169         if (refNode && isSVGGradientElement(*refNode)) {
 170             current = toSVGGradientElement(refNode);
 171
 172             // Cycle detection
 173             if (processedGradients.contains(current))
 174                 return true;
 175
 176             if (!current->renderer())
 177                 return false;
 178
 179             setGradientAttributes(current, attributes, current->hasTagName(SVGNames::linearGradientTag));
 180             processedGradients.add(current);
 181         } else {
 182             return true;
 183         }
 184     }
 185
 186     ASSERT_NOT_REACHED();
 187     return false;
 188 }
 189
 190 bool SVGLinearGradientElement::selfHasRelativeLengths() const
 191 {
 192     return m_x1->currentValue()->isRelative()
 193         || m_y1->currentValue()->isRelative()
 194         || m_x2->currentValue()->isRelative()
 195         || m_y2->currentValue()->isRelative();
 196 }
 197
 198 }