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00017 #include "neato.h"
00018 #include "simple.h"
00019
00020
00021 extern void
00022 find_ints(struct vertex vertex_list[],
00023 struct polygon polygon_list[],
00024 struct data *input, struct intersection ilist[]);
00025 int Plegal_arrangement(Ppoly_t ** polys, int n_polys)
00026 {
00027
00028 int i, j, vno, nverts, rv;
00029
00030 struct vertex *vertex_list;
00031 struct polygon *polygon_list;
00032 struct data input;
00033 struct intersection ilist[MAXINTS];
00034
00035 polygon_list = N_GNEW(n_polys, struct polygon);
00036
00037 for (i = nverts = 0; i < n_polys; i++)
00038 nverts += polys[i]->pn;
00039
00040 vertex_list = N_GNEW(nverts, struct vertex);
00041
00042 for (i = vno = 0; i < n_polys; i++) {
00043 polygon_list[i].start = &vertex_list[vno];
00044 for (j = 0; j < polys[i]->pn; j++) {
00045 vertex_list[vno].pos.x = polys[i]->ps[j].x;
00046 vertex_list[vno].pos.y = polys[i]->ps[j].y;
00047 vertex_list[vno].poly = &polygon_list[i];
00048 vertex_list[vno].active = 0;
00049 vno++;
00050 }
00051 polygon_list[i].finish = &vertex_list[vno - 1];
00052 }
00053
00054 input.nvertices = nverts;
00055 input.npolygons = n_polys;
00056
00057 find_ints(vertex_list, polygon_list, &input, ilist);
00058
00059
00060 #define EQ_PT(v,w) (((v).x == (w).x) && ((v).y == (w).y))
00061 rv = 1;
00062 {
00063 int i;
00064 struct position vft, vsd, avft, avsd;
00065 for (i = 0; i < input.ninters; i++) {
00066 vft = ilist[i].firstv->pos;
00067 avft = after(ilist[i].firstv)->pos;
00068 vsd = ilist[i].secondv->pos;
00069 avsd = after(ilist[i].secondv)->pos;
00070 if (((vft.x != avft.x) && (vsd.x != avsd.x)) ||
00071 ((vft.x == avft.x) &&
00072 !EQ_PT(vft, ilist[i]) &&
00073 !EQ_PT(avft, ilist[i])) ||
00074 ((vsd.x == avsd.x) &&
00075 !EQ_PT(vsd, ilist[i]) && !EQ_PT(avsd, ilist[i]))) {
00076 rv = 0;
00077 if (Verbose > 1) {
00078 fprintf(stderr, "\nintersection %d at %.3f %.3f\n",
00079 i, ilist[i].x, ilist[i].y);
00080 fprintf(stderr, "seg#1 : (%.3f, %.3f) (%.3f, %.3f)\n",
00081 (double) (ilist[i].firstv->pos.x)
00082 , (double) (ilist[i].firstv->pos.y)
00083 , (double) (after(ilist[i].firstv)->pos.x)
00084 , (double) (after(ilist[i].firstv)->pos.y));
00085 fprintf(stderr, "seg#2 : (%.3f, %.3f) (%.3f, %.3f)\n",
00086 (double) (ilist[i].secondv->pos.x)
00087 , (double) (ilist[i].secondv->pos.y)
00088 , (double) (after(ilist[i].secondv)->pos.x)
00089 , (double) (after(ilist[i].secondv)->pos.y));
00090 }
00091 }
00092 }
00093 }
00094 free(polygon_list);
00095 free(vertex_list);
00096 return rv;
00097 }