WebCore/svg/SVGRadialGradientElement.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/svg/SVGRadialGradientElement.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,230 @@
+/*
+    Copyright (C) 2004, 2005, 2006, 2008 Nikolas Zimmermann <zimmermann@kde.org>
+                  2004, 2005, 2006, 2007 Rob Buis <buis@kde.org>
+                  2008 Eric Seidel <eric@webkit.org>
+                  2008 Dirk Schulze <krit@webkit.org>
+    Copyright (C) Research In Motion Limited 2010. All rights reserved.
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Library General Public
+    License as published by the Free Software Foundation; either
+    version 2 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Library General Public License for more details.
+
+    You should have received a copy of the GNU Library General Public License
+    along with this library; see the file COPYING.LIB.  If not, write to
+    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+    Boston, MA 02110-1301, USA.
+*/
+
+#include "config.h"
+
+#if ENABLE(SVG)
+#include "SVGRadialGradientElement.h"
+
+#include "Attribute.h"
+#include "FloatConversion.h"
+#include "FloatPoint.h"
+#include "RadialGradientAttributes.h"
+#include "RenderSVGResourceRadialGradient.h"
+#include "SVGLength.h"
+#include "SVGNames.h"
+#include "SVGStopElement.h"
+#include "SVGTransform.h"
+#include "SVGTransformList.h"
+#include "SVGUnitTypes.h"
+
+namespace WebCore {
+
+SVGRadialGradientElement::SVGRadialGradientElement(const QualifiedName& tagName, Document* doc)
+    : SVGGradientElement(tagName, doc)
+    , m_cx(LengthModeWidth, "50%")
+    , m_cy(LengthModeHeight, "50%")
+    , m_r(LengthModeOther, "50%")
+    , m_fx(LengthModeWidth)
+    , m_fy(LengthModeHeight)
+{
+    // Spec: If the cx/cy/r attribute is not specified, the effect is as if a value of "50%" were specified.
+}
+
+SVGRadialGradientElement::~SVGRadialGradientElement()
+{
+}
+
+void SVGRadialGradientElement::parseMappedAttribute(Attribute* attr)
+{
+    if (attr->name() == SVGNames::cxAttr)
+        setCxBaseValue(SVGLength(LengthModeWidth, attr->value()));
+    else if (attr->name() == SVGNames::cyAttr)
+        setCyBaseValue(SVGLength(LengthModeHeight, attr->value()));
+    else if (attr->name() == SVGNames::rAttr) {
+        setRBaseValue(SVGLength(LengthModeOther, attr->value()));
+        if (rBaseValue().value(this) < 0.0)
+            document()->accessSVGExtensions()->reportError("A negative value for radial gradient radius <r> is not allowed");
+    } else if (attr->name() == SVGNames::fxAttr)
+        setFxBaseValue(SVGLength(LengthModeWidth, attr->value()));
+    else if (attr->name() == SVGNames::fyAttr)
+        setFyBaseValue(SVGLength(LengthModeHeight, attr->value()));
+    else
+        SVGGradientElement::parseMappedAttribute(attr);
+}
+
+void SVGRadialGradientElement::svgAttributeChanged(const QualifiedName& attrName)
+{
+    SVGGradientElement::svgAttributeChanged(attrName);
+
+    if (attrName == SVGNames::cxAttr
+        || attrName == SVGNames::cyAttr
+        || attrName == SVGNames::fxAttr
+        || attrName == SVGNames::fyAttr
+        || attrName == SVGNames::rAttr) {
+        updateRelativeLengthsInformation();
+        invalidateResourceClients();
+    }
+}
+
+void SVGRadialGradientElement::synchronizeProperty(const QualifiedName& attrName)
+{
+    SVGGradientElement::synchronizeProperty(attrName);
+
+    if (attrName == anyQName()) {
+        synchronizeCx();
+        synchronizeCy();
+        synchronizeFx();
+        synchronizeFy();
+        synchronizeR();
+        return;
+    }
+
+    if (attrName == SVGNames::cxAttr)
+        synchronizeCx();
+    else if (attrName == SVGNames::cyAttr)
+        synchronizeCy();
+    else if (attrName == SVGNames::fxAttr)
+        synchronizeFx();
+    else if (attrName == SVGNames::fyAttr)
+        synchronizeFy();
+    else if (attrName == SVGNames::rAttr)
+        synchronizeR();
+}
+
+RenderObject* SVGRadialGradientElement::createRenderer(RenderArena* arena, RenderStyle*)
+{
+    return new (arena) RenderSVGResourceRadialGradient(this);
+}
+
+RadialGradientAttributes SVGRadialGradientElement::collectGradientProperties()
+{
+    RadialGradientAttributes attributes;
+    HashSet<SVGGradientElement*> processedGradients;
+
+    bool isRadial = true;
+    SVGGradientElement* current = this;
+
+    while (current) {
+        if (!attributes.hasSpreadMethod() && current->hasAttribute(SVGNames::spreadMethodAttr))
+            attributes.setSpreadMethod((GradientSpreadMethod) current->spreadMethod());
+
+        if (!attributes.hasBoundingBoxMode() && current->hasAttribute(SVGNames::gradientUnitsAttr))
+            attributes.setBoundingBoxMode(current->gradientUnits() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX);
+
+        if (!attributes.hasGradientTransform() && current->hasAttribute(SVGNames::gradientTransformAttr))
+            attributes.setGradientTransform(current->gradientTransform()->consolidate().matrix());
+
+        if (!attributes.hasStops()) {
+            const Vector<Gradient::ColorStop>& stops(current->buildStops());
+            if (!stops.isEmpty())
+                attributes.setStops(stops);
+        }
+
+        if (isRadial) {
+            SVGRadialGradientElement* radial = static_cast<SVGRadialGradientElement*>(current);
+
+            if (!attributes.hasCx() && current->hasAttribute(SVGNames::cxAttr))
+                attributes.setCx(radial->cx());
+
+            if (!attributes.hasCy() && current->hasAttribute(SVGNames::cyAttr))
+                attributes.setCy(radial->cy());
+
+            if (!attributes.hasR() && current->hasAttribute(SVGNames::rAttr))
+                attributes.setR(radial->r());
+
+            if (!attributes.hasFx() && current->hasAttribute(SVGNames::fxAttr))
+                attributes.setFx(radial->fx());
+
+            if (!attributes.hasFy() && current->hasAttribute(SVGNames::fyAttr))
+                attributes.setFy(radial->fy());
+        }
+
+        processedGradients.add(current);
+
+        // Respect xlink:href, take attributes from referenced element
+        Node* refNode = ownerDocument()->getElementById(SVGURIReference::getTarget(current->href()));
+        if (refNode && (refNode->hasTagName(SVGNames::radialGradientTag) || refNode->hasTagName(SVGNames::linearGradientTag))) {
+            current = static_cast<SVGGradientElement*>(refNode);
+
+            // Cycle detection
+            if (processedGradients.contains(current))
+                return RadialGradientAttributes();
+
+            isRadial = current->hasTagName(SVGNames::radialGradientTag);
+        } else
+            current = 0;
+    }
+
+    // Handle default values for fx/fy
+    if (!attributes.hasFx())
+        attributes.setFx(attributes.cx());
+
+    if (!attributes.hasFy())
+        attributes.setFy(attributes.cy());
+
+    return attributes;
+}
+
+void SVGRadialGradientElement::calculateFocalCenterPointsAndRadius(const RadialGradientAttributes& attributes, FloatPoint& focalPoint, FloatPoint& centerPoint, float& radius)
+{
+    // Determine gradient focal/center points and radius
+    if (attributes.boundingBoxMode()) {
+        focalPoint = FloatPoint(attributes.fx().valueAsPercentage(), attributes.fy().valueAsPercentage());
+        centerPoint = FloatPoint(attributes.cx().valueAsPercentage(), attributes.cy().valueAsPercentage());
+        radius = attributes.r().valueAsPercentage();
+    } else {
+        focalPoint = FloatPoint(attributes.fx().value(this), attributes.fy().value(this));
+        centerPoint = FloatPoint(attributes.cx().value(this), attributes.cy().value(this));
+        radius = attributes.r().value(this);
+    }
+
+    // Eventually adjust focal points, as described below
+    float deltaX = focalPoint.x() - centerPoint.x();
+    float deltaY = focalPoint.y() - centerPoint.y();
+    float radiusMax = 0.99f * radius;
+
+    // Spec: If (fx, fy) lies outside the circle defined by (cx, cy) and r, set
+    // (fx, fy) to the point of intersection of the line through (fx, fy) and the circle.
+    // We scale the radius by 0.99 to match the behavior of FireFox.
+    if (sqrt(deltaX * deltaX + deltaY * deltaY) > radiusMax) {
+        float angle = atan2f(deltaY, deltaX);
+
+        deltaX = cosf(angle) * radiusMax;
+        deltaY = sinf(angle) * radiusMax;
+        focalPoint = FloatPoint(deltaX + centerPoint.x(), deltaY + centerPoint.y());
+    }
+}
+
+bool SVGRadialGradientElement::selfHasRelativeLengths() const
+{
+    return cy().isRelative()
+        || cy().isRelative()
+        || r().isRelative()
+        || fx().isRelative()
+        || fy().isRelative();
+}
+
+}
+
+#endif // ENABLE(SVG)