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/* $Id: wrapper.c,v 1.3 2004/12/11 19:26:11 ellson Exp $ $Revision: 1.3 $ */
/* vim:set shiftwidth=4 ts=8: */
/**********************************************************
* This software is part of the graphviz package *
* http://www.graphviz.org/ *
* *
* Copyright (c) 1994-2004 AT&T Corp. *
* and is licensed under the *
* Common Public License, Version 1.0 *
* by AT&T Corp. *
* *
* Information and Software Systems Research *
* AT&T Research, Florham Park NJ *
**********************************************************/
#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
void find_ints(struct vertex vertex_list[], struct polygon polygon_list[],
struct data *input, struct intersection ilist[]);
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 %.3f %.3f\n",
i, ilist[i].x, ilist[i].y);
fprintf(stderr, "seg#1 : (%.3f, %.3f) (%.3f, %.3f)\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 : (%.3f, %.3f) (%.3f, %.3f)\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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