#ifndef NURB_H
#define NURB_H

struct NurbSurface;

typedef struct Point3Struct {   /* 3d point */
  double x, y, z;
} Point3, Vector3;

typedef struct Point4Struct {
    double x, y, z, w;
    } Point4;
typedef Point4 Vector4;

typedef struct SurfSample {
  Point3 point, normal;   /* Point on surface, normal at that point */
  double normLen;         /* Used for normalizing normals */
  double u, v;            /* Parameters, e.g., used for texture mapping. */
  /* Note the parameter's range is determined by the surface's knot vector,
   * i.e., u goes from kvU[orderU-1] to kvU[numU], and likewise for v */
} SurfSample;


class Nurb 
{
protected:
  NurbSurface *nurbSurface;
  short complexity;
  
  
public:
  Nurb(void);
  Nurb(NurbSurface *);
  void attachNurbSurface(NurbSurface *);
  
  void setComplexity(short compl);
  short getComplexity();
  
  Point4 getControlPoint(short u, short v);
  void setControlPoint(short u, short v, Point4 pt);
  void evaluateUV(double u, double v, Point3 &pt, Point3 &norm);
  
  short  getNumU();
  short  getNumV();
  short  getOrderU();
  short  getOrderV();
  const double *getKnotU();
  const double *getKnotV();
  
  void drawEvaluation();
  SurfSample **gridEvaluation();
  
  virtual void drawTriangle(const SurfSample *, const SurfSample *, const
			    SurfSample *);
  

};

extern "C" 
{
  extern NurbSurface **readObj(char *filename);
}


#endif