PBRT_V2 总结记录 Sampling Shapes

Shape

// Shape Declarations
class Shape : public ReferenceCounted {
public:
    // Shape Interface
    Shape(const Transform *o2w, const Transform *w2o, bool ro);
    virtual ~Shape();

    virtual Point Sample(float u1, float u2, Normal *Ns) const {
        Severe("Unimplemented Shape::Sample() method called");
        return Point();
    }
    virtual float Pdf(const Point &Pshape) const {
        return 1.f / Area();
    }
    virtual Point Sample(const Point &P, float u1, float u2,
                         Normal *Ns) const {
        return Sample(u1, u2, Ns);
    }
    virtual float Pdf(const Point &p, const Vector &wi) const;

};


// Shape Declarations
class Sha