sweep_context.h

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 * Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
 * http://code.google.com/p/poly2tri/
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#ifndef SWEEP_CONTEXT_H
#define SWEEP_CONTEXT_H

#include <list>
#include <vector>
#include <cstddef>

namespace p2t {

// Inital triangle factor, seed triangle will extend 30% of
// PointSet width to both left and right.
const double kAlpha = 0.3;

struct Point;
class Triangle;
struct Node;
struct Edge;
class AdvancingFront;

class SweepContext {
public:

explicit SweepContext(const std::vector<Point*> &polyline);
~SweepContext();

void set_head(Point* p1);

Point* head();

void set_tail(Point* p1);

Point* tail();

int point_count();

Node& LocateNode(Point& point);

void RemoveNode(Node* node);

void CreateAdvancingFront(std::vector<Node*> nodes);

void MapTriangleToNodes(Triangle& t);

void AddToMap(Triangle* triangle);

Point* GetPoint(const int& index);

Point* GetPoints();

void RemoveFromMap(Triangle* triangle);

void AddHole(std::vector<Point*> polyline);

void AddPoint(Point* point);

AdvancingFront* front();

void MeshClean(Triangle& triangle);

std::vector<Triangle*> GetTriangles();
std::list<Triangle*> GetMap();

std::vector<Edge*> edge_list;

struct Basin {
  Node* left_node;
  Node* bottom_node;
  Node* right_node;
  double width;
  bool left_highest;

  Basin() : left_node(nullptr), bottom_node(nullptr), right_node(nullptr), width(0.0), left_highest(false)
  {
  }

  void Clear()
  {
    left_node = nullptr;
    bottom_node = nullptr;
    right_node = nullptr;
    width = 0.0;
    left_highest = false;
  }
};

struct EdgeEvent {
  Edge* constrained_edge;
  bool right;

  EdgeEvent() : constrained_edge(nullptr), right(false)
  {
  }
};

Basin basin;
EdgeEvent edge_event;

private:

friend class Sweep;

std::vector<Triangle*> triangles_;
std::list<Triangle*> map_;
std::vector<Point*> points_;

// Advancing front
AdvancingFront* front_;
// head point used with advancing front
Point* head_;
// tail point used with advancing front
Point* tail_;

Node *af_head_, *af_middle_, *af_tail_;

void InitTriangulation();
void InitEdges(std::vector<Point*> polyline);

};

inline AdvancingFront* SweepContext::front()
{
  return front_;
}

inline int SweepContext::point_count()
{
  return points_.size();
}

inline void SweepContext::set_head(Point* p1)
{
  head_ = p1;
}

inline Point* SweepContext::head()
{
  return head_;
}

inline void SweepContext::set_tail(Point* p1)
{
  tail_ = p1;
}

inline Point* SweepContext::tail()
{
  return tail_;
}

}

#endif