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#include <stdio.h>
#include <stdlib.h>
#include "simple.h"
/* this is all out of pathgeom.h and will eventually get included */
typedef struct Pxy_t {
double x, y;
} Pxy_t;
typedef struct Pxy_t Ppoint_t;
typedef struct Pxy_t Pvector_t;
typedef struct Ppoly_t {
Ppoint_t *ps;
int pn;
} Ppoly_t;
typedef Ppoly_t Ppolyline_t;
typedef struct Pedge_t {
Ppoint_t a, b;
} Pedge_t;
#ifdef NOTDEF
int main(int argc, char **argv) {
Ppoly_t polys[2], *polys_ptr[2];
polys[0].ps = (Ppoint_t *) malloc(3 * sizeof (Ppoint_t));
polys[1].ps = (Ppoint_t *) malloc(3 * sizeof (Ppoint_t));
polys[0].pn = 3;
polys[1].pn = 3;
polys[0].ps[0].x = 0.0; polys[0].ps[0].y = 0.0;
polys[0].ps[1].x = 0.0; polys[0].ps[1].y = 100.0;
polys[0].ps[2].x = 100.0; polys[0].ps[2].y = 0.0;
polys[1].ps[0].x = 70.0; polys[1].ps[0].y = 70.0;
polys[1].ps[1].x = 70.0; polys[1].ps[1].y = 100.0;
polys[1].ps[2].x = 100.0; polys[1].ps[2].y = 70.0;
polys_ptr[0] = &polys[0];
polys_ptr[1] = &polys[1];
if (Plegal_arrangement(polys_ptr, 2 ))
printf(" it is legal\n");
else
printf(" it is not legal\n");
}
#endif
#ifdef NOTDEF
struct vertex *after(struct vertex *v) {
if (v == v->poly->finish) return v->poly->start;
else return v + 1;
}
struct vertex *before(struct vertex *v) {
if (v == v->poly->start) return v->poly->finish;
else return v - 1;
}
#endif
int Plegal_arrangement( Ppoly_t **polys, int n_polys) {
int i, j, vno, nverts, rv;
struct vertex *vertex_list;
struct polygon *polygon_list;
struct data input ;
struct intersection ilist[10000];
polygon_list = (struct polygon *)
malloc(n_polys * sizeof(struct polygon));
for (i = nverts = 0 ; i < n_polys; i++ )
nverts += polys[i]->pn;
vertex_list = (struct vertex *)
malloc(nverts * sizeof(struct vertex));
for (i = vno = 0 ; i < n_polys; i++ ) {
polygon_list[i].start = &vertex_list[vno];
for (j = 0 ; j < polys[i]->pn ; j++ ) {
vertex_list[vno].pos.x = polys[i]->ps[j].x;
vertex_list[vno].pos.y = polys[i]->ps[j].y;
vertex_list[vno].poly = &polygon_list[i];
vno++;
}
polygon_list[i].finish = &vertex_list[vno-1];
}
input.nvertices = nverts;
input.npolygons = n_polys;
find_ints(vertex_list, polygon_list, &input, ilist);
#define EQ_PT(v,w) (((v).x == (w).x) && ((v).y == (w).y))
rv = 1;
{
int i;
struct position vft, vsd, avft, avsd;
for (i = 0; i < input.ninters; i++) {
vft = ilist[i].firstv->pos;
avft = after(ilist[i].firstv)->pos;
vsd = ilist[i].secondv->pos;
avsd = after(ilist[i].secondv)->pos;
if ( ((vft.x != avft.x) && (vsd.x != avsd.x)) ||
((vft.x == avft.x) &&
!EQ_PT(vft,ilist[i]) &&
!EQ_PT(avft,ilist[i])) ||
((vsd.x == avsd.x) &&
!EQ_PT(vsd,ilist[i]) &&
!EQ_PT(avsd,ilist[i])) ) {
rv = 0;
fprintf(stderr,"\nintersection %d at %.3lf %.3lf\n",
i,ilist[i].x,ilist[i].y);
fprintf(stderr,"seg#1 : (%.3lf, %.3lf) (%.3lf, %.3lf)\n"
,(double)(ilist[i].firstv->pos.x)
,(double)(ilist[i].firstv->pos.y)
,(double)(after(ilist[i].firstv)->pos.x)
,(double)(after(ilist[i].firstv)->pos.y));
fprintf(stderr,"seg#2 : (%.3lf, %.3lf) (%.3lf, %.3lf)\n"
,(double)(ilist[i].secondv->pos.x)
,(double)(ilist[i].secondv->pos.y)
,(double)(after(ilist[i].secondv)->pos.x)
,(double)(after(ilist[i].secondv)->pos.y));
}
}
}
free(polygon_list);
free(vertex_list);
return rv;
}
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