1 /*
2  * Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
3  * http://code.google.com/p/poly2tri/
4  *
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11  *   this list of conditions and the following disclaimer.
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16  *   used to endorse or promote products derived from this software without specific
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30  */
31 #include "sweep_context.h"
32 #include <algorithm>
33 #include "advancing_front.h"
34 
35 namespace p2t {
36 
SweepContext(std::vector<Point * > polyline)37 SweepContext::SweepContext(std::vector<Point*> polyline) :
38   front_(0),
39   head_(0),
40   tail_(0),
41   af_head_(0),
42   af_middle_(0),
43   af_tail_(0)
44 {
45   basin = Basin();
46   edge_event = EdgeEvent();
47 
48   points_ = polyline;
49 
50   InitEdges(points_);
51 }
52 
AddHole(std::vector<Point * > polyline)53 void SweepContext::AddHole(std::vector<Point*> polyline)
54 {
55   InitEdges(polyline);
56   for (unsigned int i = 0; i < polyline.size(); i++) {
57     points_.push_back(polyline[i]);
58   }
59 }
60 
AddPoint(Point * point)61 void SweepContext::AddPoint(Point* point) {
62   points_.push_back(point);
63 }
64 
GetTriangles()65 std::vector<Triangle*> SweepContext::GetTriangles()
66 {
67   return triangles_;
68 }
69 
GetMap()70 std::list<Triangle*> SweepContext::GetMap()
71 {
72   return map_;
73 }
74 
InitTriangulation()75 void SweepContext::InitTriangulation()
76 {
77   double xmax(points_[0]->x), xmin(points_[0]->x);
78   double ymax(points_[0]->y), ymin(points_[0]->y);
79 
80   // Calculate bounds.
81   for (unsigned int i = 0; i < points_.size(); i++) {
82     Point& p = *points_[i];
83     if (p.x > xmax)
84       xmax = p.x;
85     if (p.x < xmin)
86       xmin = p.x;
87     if (p.y > ymax)
88       ymax = p.y;
89     if (p.y < ymin)
90       ymin = p.y;
91   }
92 
93   double dx = kAlpha * (xmax - xmin);
94   double dy = kAlpha * (ymax - ymin);
95   head_ = new Point(xmax + dx, ymin - dy);
96   tail_ = new Point(xmin - dx, ymin - dy);
97 
98   // Sort points along y-axis
99   std::sort(points_.begin(), points_.end(), cmp);
100 
101 }
102 
InitEdges(std::vector<Point * > polyline)103 void SweepContext::InitEdges(std::vector<Point*> polyline)
104 {
105   int num_points = polyline.size();
106   for (int i = 0; i < num_points; i++) {
107     int j = i < num_points - 1 ? i + 1 : 0;
108     edge_list.push_back(new Edge(*polyline[i], *polyline[j]));
109   }
110 }
111 
GetPoint(const int & index)112 Point* SweepContext::GetPoint(const int& index)
113 {
114   return points_[index];
115 }
116 
AddToMap(Triangle * triangle)117 void SweepContext::AddToMap(Triangle* triangle)
118 {
119   map_.push_back(triangle);
120 }
121 
LocateNode(Point & point)122 Node& SweepContext::LocateNode(Point& point)
123 {
124   // TODO implement search tree
125   return *front_->LocateNode(point.x);
126 }
127 
CreateAdvancingFront(std::vector<Node * > nodes)128 void SweepContext::CreateAdvancingFront(std::vector<Node*> nodes)
129 {
130 
131   (void) nodes;
132   // Initial triangle
133   Triangle* triangle = new Triangle(*points_[0], *tail_, *head_);
134 
135   map_.push_back(triangle);
136 
137   af_head_ = new Node(*triangle->GetPoint(1), *triangle);
138   af_middle_ = new Node(*triangle->GetPoint(0), *triangle);
139   af_tail_ = new Node(*triangle->GetPoint(2));
140   front_ = new AdvancingFront(*af_head_, *af_tail_);
141 
142   // TODO: More intuitive if head is middles next and not previous?
143   //       so swap head and tail
144   af_head_->next = af_middle_;
145   af_middle_->next = af_tail_;
146   af_middle_->prev = af_head_;
147   af_tail_->prev = af_middle_;
148 }
149 
RemoveNode(Node * node)150 void SweepContext::RemoveNode(Node* node)
151 {
152   delete node;
153 }
154 
MapTriangleToNodes(Triangle & t)155 void SweepContext::MapTriangleToNodes(Triangle& t)
156 {
157   for (int i = 0; i < 3; i++) {
158     if (!t.GetNeighbor(i)) {
159       Node* n = front_->LocatePoint(t.PointCW(*t.GetPoint(i)));
160       if (n)
161         n->triangle = &t;
162     }
163   }
164 }
165 
RemoveFromMap(Triangle * triangle)166 void SweepContext::RemoveFromMap(Triangle* triangle)
167 {
168   map_.remove(triangle);
169 }
170 
MeshClean(Triangle & triangle)171 void SweepContext::MeshClean(Triangle& triangle)
172 {
173   std::vector<Triangle *> triangles;
174   triangles.push_back(&triangle);
175 
176   while(!triangles.empty()){
177 	Triangle *t = triangles.back();
178 	triangles.pop_back();
179 
180     if (t != NULL && !t->IsInterior()) {
181       t->IsInterior(true);
182       triangles_.push_back(t);
183       for (int i = 0; i < 3; i++) {
184         if (!t->constrained_edge[i])
185           triangles.push_back(t->GetNeighbor(i));
186       }
187     }
188   }
189 }
190 
~SweepContext()191 SweepContext::~SweepContext()
192 {
193 
194     // Clean up memory
195 
196     delete head_;
197     delete tail_;
198     delete front_;
199     delete af_head_;
200     delete af_middle_;
201     delete af_tail_;
202 
203     typedef std::list<Triangle*> type_list;
204 
205     for (type_list::iterator iter = map_.begin(); iter != map_.end(); ++iter) {
206         Triangle* ptr = *iter;
207         delete ptr;
208     }
209 
210      for (unsigned int i = 0; i < edge_list.size(); i++) {
211         delete edge_list[i];
212     }
213 
214 }
215 
216 }
217