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15  *     from this software without specific prior written permission.
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27  */
28 
29 #ifndef FloatQuad_h
30 #define FloatQuad_h
31 
32 #include "FloatPoint.h"
33 #include "FloatRect.h"
34 #include "IntRect.h"
35 
36 namespace WebCore {
37 
38 // A FloatQuad is a collection of 4 points, often representing the result of
39 // mapping a rectangle through transforms. When initialized from a rect, the
40 // points are in clockwise order from top left.
41 class FloatQuad {
42 public:
FloatQuad()43     FloatQuad()
44     {
45     }
46 
FloatQuad(const FloatPoint & p1,const FloatPoint & p2,const FloatPoint & p3,const FloatPoint & p4)47     FloatQuad(const FloatPoint& p1, const FloatPoint& p2, const FloatPoint& p3, const FloatPoint& p4)
48         : m_p1(p1)
49         , m_p2(p2)
50         , m_p3(p3)
51         , m_p4(p4)
52     {
53     }
54 
FloatQuad(const FloatRect & inRect)55     FloatQuad(const FloatRect& inRect)
56         : m_p1(inRect.location())
57         , m_p2(inRect.maxX(), inRect.y())
58         , m_p3(inRect.maxX(), inRect.maxY())
59         , m_p4(inRect.x(), inRect.maxY())
60     {
61     }
62 
p1()63     FloatPoint p1() const { return m_p1; }
p2()64     FloatPoint p2() const { return m_p2; }
p3()65     FloatPoint p3() const { return m_p3; }
p4()66     FloatPoint p4() const { return m_p4; }
67 
setP1(const FloatPoint & p)68     void setP1(const FloatPoint& p) { m_p1 = p; }
setP2(const FloatPoint & p)69     void setP2(const FloatPoint& p) { m_p2 = p; }
setP3(const FloatPoint & p)70     void setP3(const FloatPoint& p) { m_p3 = p; }
setP4(const FloatPoint & p)71     void setP4(const FloatPoint& p) { m_p4 = p; }
72 
73     // isEmpty tests that the bounding box is empty. This will not identify
74     // "slanted" empty quads.
isEmpty()75     bool isEmpty() const { return boundingBox().isEmpty(); }
76 
77     // Tests whether this quad can be losslessly represented by a FloatRect,
78     // that is, if two edges are parallel to the x-axis and the other two
79     // are parallel to the y-axis. If this method returns true, the
80     // corresponding FloatRect can be retrieved with boundingBox().
81     bool isRectilinear() const;
82 
83     // Tests whether the given point is inside, or on an edge or corner of this quad.
84     bool containsPoint(const FloatPoint&) const;
85 
86     // Tests whether the four corners of other are inside, or coincident with the sides of this quad.
87     // Note that this only works for convex quads, but that includes all quads that originate
88     // from transformed rects.
89     bool containsQuad(const FloatQuad&) const;
90 
91     FloatRect boundingBox() const;
enclosingBoundingBox()92     IntRect enclosingBoundingBox() const
93     {
94         return enclosingIntRect(boundingBox());
95     }
96 
move(const FloatSize & offset)97     void move(const FloatSize& offset)
98     {
99         m_p1 += offset;
100         m_p2 += offset;
101         m_p3 += offset;
102         m_p4 += offset;
103     }
104 
move(float dx,float dy)105     void move(float dx, float dy)
106     {
107         m_p1.move(dx, dy);
108         m_p2.move(dx, dy);
109         m_p3.move(dx, dy);
110         m_p4.move(dx, dy);
111     }
112 
113 private:
114     FloatPoint m_p1;
115     FloatPoint m_p2;
116     FloatPoint m_p3;
117     FloatPoint m_p4;
118 };
119 
120 inline FloatQuad& operator+=(FloatQuad& a, const FloatSize& b)
121 {
122     a.move(b);
123     return a;
124 }
125 
126 inline FloatQuad& operator-=(FloatQuad& a, const FloatSize& b)
127 {
128     a.move(-b.width(), -b.height());
129     return a;
130 }
131 
132 inline bool operator==(const FloatQuad& a, const FloatQuad& b)
133 {
134     return a.p1() == b.p1() &&
135            a.p2() == b.p2() &&
136            a.p3() == b.p3() &&
137            a.p4() == b.p4();
138 }
139 
140 inline bool operator!=(const FloatQuad& a, const FloatQuad& b)
141 {
142     return a.p1() != b.p1() ||
143            a.p2() != b.p2() ||
144            a.p3() != b.p3() ||
145            a.p4() != b.p4();
146 }
147 
148 }   // namespace WebCore
149 
150 
151 #endif // FloatQuad_h
152 
153