#define DELETED -2

#define le 0
#define re 1

struct	Freenode	{
    struct Freenode	*nextfree;
};
struct	Freelist	{
    struct Freenode	*head;
    int			nodesize;
};


struct Point	{
    double x,y;
};

/* structure used both for sites and for vertices */
struct Site	{
    struct	Point	coord;
    int		sitenbr;
    int		refcnt;
};

struct Edge	{
    double	a,b,c;
    struct Site	*ep[2];
    struct Site	*reg[2];
    int		edgenbr;
};

struct Halfedge {
    struct Halfedge *ELleft, *ELright;
    struct Edge	    *ELedge;
    int		     ELrefcnt;
    char	     ELpm;
    struct Site	    *vertex;
    double	     ystar;
    struct Halfedge *PQnext;
};

#ifdef MAIN
int triangulate, sorted, plot, debug;
struct	Site	*sites;
int		nsites;
int		siteidx;
int		sqrt_nsites;
int		nvertices;
struct 	Freelist sfl;
struct	Site	*bottomsite;
int 		nedges;
struct	Freelist efl;
double  xmin, xmax, ymin, ymax, deltax, deltay;
struct  Freelist	hfl;
struct	Halfedge *ELleftend, *ELrightend;
int 	ELhashsize;
struct	Halfedge **ELhash;
int PQhashsize;
struct	Halfedge *PQhash;
int PQcount;
int PQmin;
#else
extern int triangulate, sorted, plot, debug;
extern struct	Site	*sites;
extern int		nsites;
extern int		siteidx;
extern int		sqrt_nsites;
extern int		nvertices;
extern struct 	Freelist sfl;
extern struct	Site	*bottomsite;
extern int 		nedges;
extern struct	Freelist efl;
extern double  xmin, xmax, ymin, ymax, deltax, deltay;
extern struct  Freelist	hfl;
extern struct	Halfedge *ELleftend, *ELrightend;
extern int 	ELhashsize;
extern struct	Halfedge **ELhash;
extern int PQhashsize;
extern struct	Halfedge *PQhash;
extern int PQcount;
extern int PQmin;
#endif

/* sw_edgelist.c */
int ELinitialize(void);
struct Halfedge *HEcreate(struct Edge *, int);
int ELinsert(struct Halfedge *, struct Halfedge *);
struct Halfedge *ELgethash(int);
struct Halfedge *ELleftbnd(struct Point *);
int ELdelete(struct Halfedge *);
struct Halfedge *ELright(struct Halfedge *);
struct Halfedge *ELleft(struct Halfedge *);
struct Site *leftreg(struct Halfedge *);
struct Site *rightreg(struct Halfedge *);
/* sw_geometry.c */
int geominit(void);
struct Edge *bisect(struct Site *, struct Site *);
struct Site *intersect(struct Halfedge *, struct Halfedge *);
int right_of(struct Halfedge *, struct Point *);
int endpoint(struct Edge *, int, struct Site *);
double dist(struct Site *, struct Site *);
int makevertex(struct Site *);
int deref(struct Site *);
int ref(struct Site *);
/* sw_heap.c */
int PQinsert(struct Halfedge *, struct Site *, double);
int PQdelete(struct Halfedge *);
int PQbucket(struct Halfedge *);
int PQempty(void);
struct Point PQ_min(void);
struct Halfedge *PQextractmin(void);
int PQinitialize(void);
/* sw_main.c */
int scomp(const void *, const void *);
struct Site *nextone(void);
int readsites( void );
struct Site *readone(void);
/* sw_memory.c */
int freeinit(struct Freelist *, int);
char *getfree(struct Freelist *);
int makefree(struct Freenode *, struct Freelist *);
char *myalloc(unsigned);
/* sw_output.c */
int openpl(void);
int line(int,int,int,int);
int circle(int,int,int);
int range(int,int,int,int);
int out_bisector(struct Edge *);
int out_ep(struct Edge *);
int out_vertex(struct Site *);
int out_site(struct Site *);
int out_triple(struct Site *, struct Site *, struct Site *);
int plotinit(void);
int clip_line(struct Edge *);
/* sw_voronoi.c */
int voronoi(int, struct Site *(*)(void));