ScallopedSector.h

// $Id: ScallopedSector.h,v 1.3 2006/07/06 23:30:24 zr Exp $

#include <vector>

typedef struct {
        Vec2 P;
        float r, sign, d, theta, integralAtStart;
        float rSqrd, dSqrd;
} ArcData;

class ScallopedSector
{
public:
        Vec2 P;
        float a1, a2, area;
        
        ArcData arcs[2];

public:
        ScallopedSector(Vec2 &_Pt, float _a1, float _a2, Vec2 &P1, float r1, float sign1, Vec2 &P2, float r2, float sign2);

        float calcAreaToAngle(float angle);
        float calcAngleForArea(float area, RNG &rng);
        Vec2 sample(RNG &rng);

        float distToCurve(float angle, int index);

        void subtractDisk(Vec2 &C, float r, std::vector<ScallopedSector> *regions);

private:
        float canonizeAngle(float angle);

        void distToCircle(float angle, Vec2 &C, float r, float *d1_out, float *d2_out);
};

class ScallopedRegion
{
public:
        std::vector<ScallopedSector> *regions;
        float minArea;
        float area;

public:
        ScallopedRegion(Vec2 &P, float r1, float r2, float minArea=.00000001);
        ~ScallopedRegion();

        bool isEmpty() { return regions->size()==0; }
        void subtractDisk(Vec2 C, float r);

        Vec2 sample(RNG &rng);
};

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