boxf*
partition (cell* cells, int ncells, int* nrects, boxf bb)
{
int nsegs = 4*(ncells+1);
segment_t* segs = N_GNEW(nsegs+1, segment_t);
int* permute = N_NEW(nsegs+1, int);
int hd_size, vd_size;
int i, j, cnt = 0;
boxf* rs;
int ntraps = TRSIZE(nsegs);
trap_t* trs = N_GNEW(ntraps, trap_t);
boxf* hor_decomp = N_NEW(ntraps, boxf);
boxf* vert_decomp = N_NEW(ntraps, boxf);
int nt;
/* fprintf (stderr, "cells = %d segs = %d traps = %d\n", ncells, nsegs, ntraps); */
genSegments (cells, ncells, bb, segs, 0);
#if 0
fprintf (stderr, "%d\n\n", ncells+1);
for (i = 1; i<= nsegs; i++) {
if (i%4 == 1) fprintf(stderr, "4\n");
fprintf (stderr, "%f %f\n", segs[i].v0.x, segs[i].v0.y);
if (i%4 == 0) fprintf(stderr, "\n");
}
#endif
srand48(173);
generateRandomOrdering (nsegs, permute);
nt = construct_trapezoids(nsegs, segs, permute, ntraps, trs);
/* fprintf (stderr, "hor traps = %d\n", nt); */
hd_size = monotonate_trapezoids (nsegs, segs, trs, 0, hor_decomp);
genSegments (cells, ncells, bb, segs, 1);
generateRandomOrdering (nsegs, permute);
nt = construct_trapezoids(nsegs, segs, permute, ntraps, trs);
/* fprintf (stderr, "ver traps = %d\n", nt); */
vd_size = monotonate_trapezoids (nsegs, segs, trs, 1, vert_decomp);
rs = N_NEW (hd_size*vd_size, boxf);
for (i=0; i<vd_size; i++)
for (j=0; j<hd_size; j++)
if (rectIntersect(&rs[cnt], &vert_decomp[i], &hor_decomp[j]))
cnt++;
rs = RALLOC (cnt, rs, boxf);
free (segs);
free (permute);
free (trs);
free (hor_decomp);
free (vert_decomp);
*nrects = cnt;
return rs;
}
int triangulate_polygon(int ncontours, int cntr[], double (*vertices)[2], int (*triangles)[3])
{
int i;
int nmonpoly, ccount, npoints, genus;
int n;
memset((void *)seg, 0, sizeof(seg));
ccount = 0;
i = 1;
while (ccount < ncontours)
{
int j;
int first, last;
npoints = cntr[ccount];
first = i;
last = first + npoints - 1;
for (j = 0; j < npoints; j++, i++)
{
seg[i].v0.x = vertices[i][0];
seg[i].v0.y = vertices[i][1];
if (i == last)
{
seg[i].next = first;
seg[i].prev = i-1;
seg[i-1].v1 = seg[i].v0;
}
else if (i == first)
{
seg[i].next = i+1;
seg[i].prev = last;
seg[last].v1 = seg[i].v0;
}
else
{
seg[i].prev = i-1;
seg[i].next = i+1;
seg[i-1].v1 = seg[i].v0;
}
seg[i].is_inserted = FALSE;
}
ccount++;
}
genus = ncontours - 1;
n = i-1;
initialise(n);
construct_trapezoids(n);
nmonpoly = monotonate_trapezoids(n);
triangulate_monotone_polygons(n, nmonpoly, triangles);
return 0;
}
