1/* 2 * Copyright (C) 2012 Google, Inc. 3 * 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 UNIVERSITY OF SZEGED ``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 UNIVERSITY OF SZEGED 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 29#include "core/rendering/svg/RenderSVGEllipse.h" 30 31#include "core/svg/SVGCircleElement.h" 32#include "core/svg/SVGEllipseElement.h" 33#include "platform/graphics/GraphicsContext.h" 34 35namespace blink { 36 37RenderSVGEllipse::RenderSVGEllipse(SVGGraphicsElement* node) 38 : RenderSVGShape(node) 39 , m_usePathFallback(false) 40{ 41} 42 43RenderSVGEllipse::~RenderSVGEllipse() 44{ 45} 46 47void RenderSVGEllipse::updateShapeFromElement() 48{ 49 // Before creating a new object we need to clear the cached bounding box 50 // to avoid using garbage. 51 m_fillBoundingBox = FloatRect(); 52 m_strokeBoundingBox = FloatRect(); 53 m_center = FloatPoint(); 54 m_radii = FloatSize(); 55 m_usePathFallback = false; 56 57 calculateRadiiAndCenter(); 58 59 // Spec: "A negative value is an error. A value of zero disables rendering of the element." 60 if (m_radii.width() < 0 || m_radii.height() < 0) 61 return; 62 63 if (!m_radii.isEmpty()) { 64 // Fallback to RenderSVGShape if shape has a non-scaling stroke. 65 if (hasNonScalingStroke()) { 66 RenderSVGShape::updateShapeFromElement(); 67 m_usePathFallback = true; 68 return; 69 } 70 } 71 72 m_fillBoundingBox = FloatRect(m_center.x() - m_radii.width(), m_center.y() - m_radii.height(), 2 * m_radii.width(), 2 * m_radii.height()); 73 m_strokeBoundingBox = m_fillBoundingBox; 74 if (style()->svgStyle().hasStroke()) 75 m_strokeBoundingBox.inflate(strokeWidth() / 2); 76} 77 78void RenderSVGEllipse::calculateRadiiAndCenter() 79{ 80 ASSERT(element()); 81 if (isSVGCircleElement(*element())) { 82 SVGCircleElement& circle = toSVGCircleElement(*element()); 83 84 SVGLengthContext lengthContext(&circle); 85 float radius = circle.r()->currentValue()->value(lengthContext); 86 m_radii = FloatSize(radius, radius); 87 m_center = FloatPoint(circle.cx()->currentValue()->value(lengthContext), circle.cy()->currentValue()->value(lengthContext)); 88 return; 89 } 90 91 SVGEllipseElement& ellipse = toSVGEllipseElement(*element()); 92 93 SVGLengthContext lengthContext(&ellipse); 94 m_radii = FloatSize(ellipse.rx()->currentValue()->value(lengthContext), ellipse.ry()->currentValue()->value(lengthContext)); 95 m_center = FloatPoint(ellipse.cx()->currentValue()->value(lengthContext), ellipse.cy()->currentValue()->value(lengthContext)); 96} 97 98void RenderSVGEllipse::fillShape(GraphicsContext* context) const 99{ 100 if (m_usePathFallback) { 101 RenderSVGShape::fillShape(context); 102 return; 103 } 104 context->fillEllipse(m_fillBoundingBox); 105} 106 107void RenderSVGEllipse::strokeShape(GraphicsContext* context) const 108{ 109 if (!style()->svgStyle().hasVisibleStroke()) 110 return; 111 if (m_usePathFallback) { 112 RenderSVGShape::strokeShape(context); 113 return; 114 } 115 context->strokeEllipse(m_fillBoundingBox); 116} 117 118bool RenderSVGEllipse::shapeDependentStrokeContains(const FloatPoint& point) 119{ 120 // The optimized contains code below does not support non-smooth strokes so we need 121 // to fall back to RenderSVGShape::shapeDependentStrokeContains in these cases. 122 if (m_usePathFallback || !hasSmoothStroke()) { 123 if (!hasPath()) 124 RenderSVGShape::updateShapeFromElement(); 125 return RenderSVGShape::shapeDependentStrokeContains(point); 126 } 127 128 float halfStrokeWidth = strokeWidth() / 2; 129 FloatPoint center = FloatPoint(m_center.x() - point.x(), m_center.y() - point.y()); 130 131 // This works by checking if the point satisfies the ellipse equation, 132 // (x/rX)^2 + (y/rY)^2 <= 1, for the outer but not the inner stroke. 133 float xrXOuter = center.x() / (m_radii.width() + halfStrokeWidth); 134 float yrYOuter = center.y() / (m_radii.height() + halfStrokeWidth); 135 if (xrXOuter * xrXOuter + yrYOuter * yrYOuter > 1.0) 136 return false; 137 138 float xrXInner = center.x() / (m_radii.width() - halfStrokeWidth); 139 float yrYInner = center.y() / (m_radii.height() - halfStrokeWidth); 140 return xrXInner * xrXInner + yrYInner * yrYInner >= 1.0; 141} 142 143bool RenderSVGEllipse::shapeDependentFillContains(const FloatPoint& point, const WindRule fillRule) const 144{ 145 if (m_usePathFallback) 146 return RenderSVGShape::shapeDependentFillContains(point, fillRule); 147 148 FloatPoint center = FloatPoint(m_center.x() - point.x(), m_center.y() - point.y()); 149 150 // This works by checking if the point satisfies the ellipse equation. 151 // (x/rX)^2 + (y/rY)^2 <= 1 152 float xrX = center.x() / m_radii.width(); 153 float yrY = center.y() / m_radii.height(); 154 return xrX * xrX + yrY * yrY <= 1.0; 155} 156 157} 158