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34 
35 
36 #include "Segment.hpp"
37 #include "HexGrid.hpp"
38 
39 namespace hexer
40 {
41 
42 // The segment is normalized if necessary.
possibleRoot(HexGrid * grid)43 bool Segment::possibleRoot(HexGrid *grid)
44 {
45     if (m_side == 3)
46     {
47         m_side = 0;
48         m_hex = grid->getHexagon(m_hex->x(), m_hex->y() + 1);
49     }
50     return m_hex->possibleRoot() && (m_side == 0);
51 }
52 
53 // When we're traversing a hexagon counter-clockwise, determine
54 // the next segment we'll traverse assume we're taking a right turn.
rightAntiClockwise(HexGrid * grid)55 Segment Segment::rightAntiClockwise(HexGrid *grid)
56 {
57     Segment next;
58     static int nextside[] = { 5, 0, 1, 2, 3, 4 };
59     static int neighborside[] = { 1, 2, 3, 4, 5, 0 };
60 
61     Coord coord = m_hex->neighborCoord(neighborside[m_side]);
62     next.m_side = nextside[m_side];
63     next.m_hex = grid->getHexagon(coord.m_x, coord.m_y);
64     return next;
65 }
66 
67 // When we're traversing a hexagon counter-clockwise, determine the
68 // next segment we'll traverse assuming we're taking a right turn.
leftAntiClockwise(HexGrid * grid)69 Segment Segment::leftAntiClockwise(HexGrid *grid)
70 {
71     static int nextside[] = { 1, 2, 3, 4, 5, 0 };
72 
73     (void)grid; //unused
74     Segment next(*this);
75     next.m_side = nextside[next.m_side];
76     return next;
77 }
78 
79 // When we're travsersing a hexagon clockwise, determine the
80 // next segment we'll traverse assume we're taking a right turn.
rightClockwise(HexGrid * grid)81 Segment Segment::rightClockwise(HexGrid *grid)
82 {
83     static int nextside[] = { 5, 0, 1, 2, 3, 4 };
84 
85     (void)grid; //unused
86     Segment next(*this);
87     next.m_side = nextside[next.m_side];
88     return next;
89 }
90 
91 // When we're traversing a hexagon clockwise, determine the next segment
92 // we'll traverse assume we're taking a left turn.
leftClockwise(HexGrid * grid)93 Segment Segment::leftClockwise(HexGrid *grid)
94 {
95     Segment next;
96     static int nextside[] = { 1, 2, 3, 4, 5, 0 };
97     static int neighborside[] = { 5, 0, 1, 2, 3, 4 };
98 
99     Coord coord = m_hex->neighborCoord(neighborside[m_side]);
100     next.m_side = nextside[m_side];
101     next.m_hex = grid->getHexagon(coord.m_x, coord.m_y);
102     return next;
103 }
104 
105 // Change the edge so that it has side 0-2 if necessary.
normalize(HexGrid * grid)106 void Segment::normalize(HexGrid *grid)
107 {
108     if (m_side >= 3)
109     {
110         Coord coord = m_hex->neighborCoord(m_side);
111         m_side -= 3;
112         m_hex = grid->getHexagon(coord.m_x, coord.m_y);
113     }
114 }
115 
startPos(HexGrid * grid) const116 Point Segment::startPos(HexGrid *grid) const
117 {
118     int side = m_side - 1;
119     side = side < 0 ? 5 : side;
120     return pos(grid, grid->offset(side));
121 }
122 
endPos(HexGrid * grid) const123 Point Segment::endPos(HexGrid *grid) const
124 {
125     return pos(grid, grid->offset(m_side));
126 }
127 
pos(HexGrid * grid,const Point & offset) const128 Point Segment::pos(HexGrid *grid, const Point& offset) const
129 {
130     Point pos;
131     pos.m_x = m_hex->x() * grid->width();
132     pos.m_y = m_hex->y() * grid->height();
133     if (m_hex->xodd())
134     {
135         pos.m_y += (grid->height() / 2);
136     }
137     return pos + offset + grid->origin();
138 }
139 
operator ==(const Segment & s1,const Segment & s2)140 bool operator == (const Segment& s1, const Segment &s2)
141 {
142     static int sharedside[] = { 3, 4, 5, 0, 1, 2 };
143     static int evenx[] = { 0, -1, -1, 0, 1, 1 };
144     static int eveny[] = { -1, -1, 0, 1, 0, -1 };
145     static int oddx[] = { 0, -1, -1, 0, 1, 1, };
146     static int oddy[] = { -1, 0, 1, 1, 1, 0 };
147     if (s1.m_hex == s2.m_hex && s1.m_side == s2.m_side)
148         return true;
149     if (s2.m_side == sharedside[s1.m_side])
150     {
151         int xinc;
152         int yinc;
153         if (s1.m_hex->xeven())
154         {
155             xinc = evenx[s1.m_side];
156             yinc = eveny[s1.m_side];
157         }
158         else
159         {
160             xinc = oddx[s1.m_side];
161             yinc = oddy[s1.m_side];
162         }
163         if ((s2.m_hex->x() == s1.m_hex->x() + xinc) &&
164             (s2.m_hex->y() == s1.m_hex->y() + yinc))
165         {
166             return true;
167         }
168     }
169     return false;
170 }
171 
operator !=(const Segment & s1,const Segment & s2)172 bool operator != (const Segment& s1, const Segment &s2)
173 {
174     return !(s1 == s2);
175 }
176 
operator <<(std::ostream & os,const Segment & s)177 std::ostream& operator << (std::ostream& os, const Segment &s)
178 {
179     os << s.m_hex->x() << "/" << s.m_hex->y() << " - " << s.m_side;
180     return os;
181 };
182 
183 } // namespace hexer
184 
185