1 /* 2 * Copyright (C) 2012 Adobe Systems Incorporated. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above 9 * copyright notice, this list of conditions and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above 12 * copyright notice, this list of conditions and the following 13 * disclaimer in the documentation and/or other materials 14 * provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 19 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 20 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 21 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 23 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 25 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 27 * OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #ifndef FloatPolygon_h 31 #define FloatPolygon_h 32 33 #include "platform/PODIntervalTree.h" 34 #include "platform/geometry/FloatPoint.h" 35 #include "platform/geometry/FloatRect.h" 36 #include "platform/graphics/GraphicsTypes.h" 37 #include "wtf/OwnPtr.h" 38 #include "wtf/PassOwnPtr.h" 39 #include "wtf/Vector.h" 40 41 namespace blink { 42 43 class FloatPolygonEdge; 44 45 // This class is used by PODIntervalTree for debugging. 46 #ifndef NDEBUG 47 template <class> struct ValueToString; 48 #endif 49 50 class PLATFORM_EXPORT FloatPolygon { 51 public: 52 FloatPolygon(PassOwnPtr<Vector<FloatPoint> > vertices, WindRule fillRule); 53 54 const FloatPoint& vertexAt(unsigned index) const { return (*m_vertices)[index]; } 55 unsigned numberOfVertices() const { return m_vertices->size(); } 56 57 WindRule fillRule() const { return m_fillRule; } 58 59 const FloatPolygonEdge& edgeAt(unsigned index) const { return m_edges[index]; } 60 unsigned numberOfEdges() const { return m_edges.size(); } 61 62 FloatRect boundingBox() const { return m_boundingBox; } 63 bool overlappingEdges(float minY, float maxY, Vector<const FloatPolygonEdge*>& result) const; 64 bool contains(const FloatPoint&) const; 65 bool isEmpty() const { return m_empty; } 66 67 private: 68 typedef PODInterval<float, FloatPolygonEdge*> EdgeInterval; 69 typedef PODIntervalTree<float, FloatPolygonEdge*> EdgeIntervalTree; 70 71 bool containsNonZero(const FloatPoint&) const; 72 bool containsEvenOdd(const FloatPoint&) const; 73 74 OwnPtr<Vector<FloatPoint> > m_vertices; 75 WindRule m_fillRule; 76 FloatRect m_boundingBox; 77 bool m_empty; 78 Vector<FloatPolygonEdge> m_edges; 79 EdgeIntervalTree m_edgeTree; // Each EdgeIntervalTree node stores minY, maxY, and a ("UserData") pointer to a FloatPolygonEdge. 80 81 }; 82 83 class PLATFORM_EXPORT VertexPair { 84 public: 85 virtual ~VertexPair() { } 86 87 virtual const FloatPoint& vertex1() const = 0; 88 virtual const FloatPoint& vertex2() const = 0; 89 90 float minX() const { return std::min(vertex1().x(), vertex2().x()); } 91 float minY() const { return std::min(vertex1().y(), vertex2().y()); } 92 float maxX() const { return std::max(vertex1().x(), vertex2().x()); } 93 float maxY() const { return std::max(vertex1().y(), vertex2().y()); } 94 95 bool intersection(const VertexPair&, FloatPoint&) const; 96 }; 97 98 class PLATFORM_EXPORT FloatPolygonEdge : public VertexPair { 99 friend class FloatPolygon; 100 public: 101 virtual const FloatPoint& vertex1() const OVERRIDE 102 { 103 ASSERT(m_polygon); 104 return m_polygon->vertexAt(m_vertexIndex1); 105 } 106 107 virtual const FloatPoint& vertex2() const OVERRIDE 108 { 109 ASSERT(m_polygon); 110 return m_polygon->vertexAt(m_vertexIndex2); 111 } 112 113 const FloatPolygonEdge& previousEdge() const 114 { 115 ASSERT(m_polygon && m_polygon->numberOfEdges() > 1); 116 return m_polygon->edgeAt((m_edgeIndex + m_polygon->numberOfEdges() - 1) % m_polygon->numberOfEdges()); 117 } 118 119 const FloatPolygonEdge& nextEdge() const 120 { 121 ASSERT(m_polygon && m_polygon->numberOfEdges() > 1); 122 return m_polygon->edgeAt((m_edgeIndex + 1) % m_polygon->numberOfEdges()); 123 } 124 125 const FloatPolygon* polygon() const { return m_polygon; } 126 unsigned vertexIndex1() const { return m_vertexIndex1; } 127 unsigned vertexIndex2() const { return m_vertexIndex2; } 128 unsigned edgeIndex() const { return m_edgeIndex; } 129 130 private: 131 // Edge vertex index1 is less than index2, except the last edge, where index2 is 0. When a polygon edge 132 // is defined by 3 or more colinear vertices, index2 can be the the index of the last colinear vertex. 133 unsigned m_vertexIndex1; 134 unsigned m_vertexIndex2; 135 unsigned m_edgeIndex; 136 const FloatPolygon* m_polygon; 137 }; 138 139 // These structures are used by PODIntervalTree for debugging. 140 #ifndef NDEBUG 141 template <> struct ValueToString<float> { 142 static String string(const float value) { return String::number(value); } 143 }; 144 145 template<> struct ValueToString<FloatPolygonEdge*> { 146 static String string(const FloatPolygonEdge* edge) { return String::format("%p (%f,%f %f,%f)", edge, edge->vertex1().x(), edge->vertex1().y(), edge->vertex2().x(), edge->vertex2().y()); } 147 }; 148 #endif 149 150 } // namespace blink 151 152 #endif // FloatPolygon_h 153
