sweep.h

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 * Poly2Tri Copyright (c) 2009-2010, Poly2Tri Contributors
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 */
 
#ifndef SWEEP_H
#define SWEEP_H
 
#include <vector>
 
namespace p2t {
 
class SweepContext;
struct Node;
struct Point;
struct Edge;
class Triangle;
 
class Sweep 
{
public:

  void Triangulate(SweepContext& tcx);
  
  ~Sweep();
 
private:

  void SweepPoints(SweepContext& tcx);

  Node& PointEvent(SweepContext& tcx, Point& point);

  void EdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
 
  void EdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle* triangle, Point& point);

  Node& NewFrontTriangle(SweepContext& tcx, Point& point, Node& node);

  void Fill(SweepContext& tcx, Node& node);

  bool Legalize(SweepContext& tcx, Triangle& t);

  bool Incircle(Point& pa, Point& pb, Point& pc, Point& pd);

  void RotateTrianglePair(Triangle& t, Point& p, Triangle& ot, Point& op);

  void FillAdvancingFront(SweepContext& tcx, Node& n);
  
  // Decision-making about when to Fill hole. 
  // Contributed by ToolmakerSteve2
  bool LargeHole_DontFill(Node* node);
  bool AngleExceeds90Degrees(Point* origin, Point* pa, Point* pb);
  bool AngleExceedsPlus90DegreesOrIsNegative(Point* origin, Point* pa, Point* pb);
  double Angle(Point& origin, Point& pa, Point& pb);

  double HoleAngle(Node& node);

  double BasinAngle(Node& node);

  void FillBasin(SweepContext& tcx, Node& node);

  void FillBasinReq(SweepContext& tcx, Node* node);
 
  bool IsShallow(SweepContext& tcx, Node& node);
 
  bool IsEdgeSideOfTriangle(Triangle& triangle, Point& ep, Point& eq);
 
  void FillEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
 
  void FillRightAboveEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
 
  void FillRightBelowEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
 
  void FillRightConcaveEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
 
  void FillRightConvexEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
 
  void FillLeftAboveEdgeEvent(SweepContext& tcx, Edge* edge, Node* node);
 
  void FillLeftBelowEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
 
  void FillLeftConcaveEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
 
  void FillLeftConvexEdgeEvent(SweepContext& tcx, Edge* edge, Node& node);
 
  void FlipEdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle* t, Point& p);

  Triangle& NextFlipTriangle(SweepContext& tcx, int o, Triangle&  t, Triangle& ot, Point& p, Point& op);

  Point& NextFlipPoint(const Point& ep, const Point& eq, const Triangle& ot, const Point& op);

  void FlipScanEdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle& flip_triangle, Triangle& t, Point& p);
 
  void FinalizationPolygon(SweepContext& tcx);
 
  std::vector<Node*> nodes_;
 
};
 
}
 
#endif