unix.c

DT三角化实现

    Gc   - centrums\n\
    Gh   - hyperplane intersections\n\
    Gr   - ridges\n\
    GDn  - drop dimension n in 3-d and 4-d output\n\
    Gt   - for 3-d 'd', transparent outer ridges\n\
\n\
Print options:\n\
    PAn  - keep n largest facets by area\n\
    Pdk:n - drop facet if normal[k] <= n (default 0.0)\n\
    PDk:n - drop facet if normal[k] >= n\n\
    Pg   - print good facets (needs 'QGn' or 'QVn')\n\
    PFn  - keep facets whose area is at least n\n\
    PG   - print neighbors of good facets\n\
    PMn  - keep n facets with most merges\n\
    Po   - force output.  If error, output neighborhood of facet\n\
    Pp   - do not report precision problems\n\
\n\
    .    - list of all options\n\
    -    - one line descriptions of all options\n\
";
/* for opts, don't assign 'e' or 'E' to a flag (already used for exponent) */

/*-<a                             href="qh-qhull.htm#TOC"
  >-------------------------------</a><a name="prompt2">-</a>

  qh_prompt2
    synopsis for qhull
*/
char qh_prompt2[]= "\n\
qhull- compute convex hulls and related structures.  Qhull %s\n\
    input (stdin): dimension, n, point coordinates\n\
    comments start with a non-numeric character\n\
    halfspace: use dim+1 and put offsets after coefficients\n\
\n\
options (qh-quick.htm):\n\
    d    - Delaunay triangulation by lifting points to a paraboloid\n\
    d Qu - furthest-site Delaunay triangulation (upper convex hull)\n\
    v    - Voronoi diagram as the dual of the Delaunay triangulation\n\
    v Qu - furthest-site Voronoi diagram\n\
    H1,1 - Halfspace intersection about [1,1,0,...] via polar duality\n\
    Qt   - triangulated output\n\
    QJ   - joggled input instead of merged facets\n\
    Tv   - verify result: structure, convexity, and point inclusion\n\
    .    - concise list of all options\n\
    -    - one-line description of all options\n\
\n\
Output options (subset):\n\
    s    - summary of results (default)\n\
    i    - vertices incident to each facet\n\
    n    - normals with offsets\n\
    p    - vertex coordinates (if 'Qc', includes coplanar points)\n\
           if 'v', Voronoi vertices\n\
    Fp   - halfspace intersections\n\
    Fx   - extreme points (convex hull vertices)\n\
    FA   - compute total area and volume\n\
    o    - OFF format (if 'v', outputs Voronoi regions)\n\
    G    - Geomview output (2-d, 3-d and 4-d)\n\
    m    - Mathematica output (2-d and 3-d)\n\
    QVn  - print facets that include point n, -n if not\n\
    TO file- output results to file, may be enclosed in single quotes\n\
\n\
examples:\n\
    rbox c d D2 | qhull Qc s f Fx | more      rbox 1000 s | qhull Tv s FA\n\
    rbox 10 D2 | qhull d QJ s i TO result     rbox 10 D2 | qhull v Qbb Qt p\n\
    rbox 10 D2 | qhull d Qu QJ m              rbox 10 D2 | qhull v Qu QJ o\n\
    rbox c | qhull n                          rbox c | qhull FV n | qhull H Fp\n\
    rbox d D12 | qhull QR0 FA                 rbox c D7 | qhull FA TF1000\n\
    rbox y 1000 W0 | qhull                    rbox 10 | qhull v QJ o Fv\n\
\n\
";
/* for opts, don't assign 'e' or 'E' to a flag (already used for exponent) */

/*-<a                             href="qh-qhull.htm#TOC"
  >-------------------------------</a><a name="prompt3">-</a>

  qh_prompt3
    concise prompt for qhull
*/
char qh_prompt3[]= "\n\
Qhull %s.\n\
Except for 'F.' and 'PG', upper-case options take an argument.\n\
\n\
 delaunay       voronoi	       Geomview       Halfspace      facet_dump\n\
 incidences     mathematica    normals        OFF_format     points\n\
 summary\n\
\n\
 Farea          FArea-total    Fcoplanars     FCentrums      Fd-cdd-in\n\
 FD-cdd-out     FF-dump-xridge Finner         FIDs           Fmerges\n\
 Fneighbors     FNeigh-vertex  Fouter         FOptions       Fpoint-intersect\n\
 FPoint_near    FQhull         Fsummary       FSize          Ftriangles\n\
 Fvertices      Fvoronoi       FVertex-ave    Fxtremes       FMaple\n\
\n\
 Gvertices      Gpoints        Gall_points    Gno_planes     Ginner\n\
 Gcentrums      Ghyperplanes   Gridges        Gouter         GDrop_dim\n\
 Gtransparent\n\
\n\
 PArea-keep     Pdrop d0:0D0   Pgood          PFacet_area_keep\n\
 PGood_neighbors PMerge-keep   Poutput_forced Pprecision_not\n\
\n\
 QbBound 0:0.5  Qbk:0Bk:0_drop QbB-scale-box  Qbb-scale-last Qcoplanar\n\
 Qfurthest      Qgood_only     QGood_point    Qinterior      Qmax_out\n\
 QJoggle        Qrandom        QRotate        Qsearch_1st    Qtriangulate\n\
 QupperDelaunay QVertex_good   Qvneighbors    Qxact_merge    Qzinfinite\n\
\n\
 Q0_no_premerge Q1_no_angle    Q2_no_independ Q3_no_redundant Q4_no_old\n\
 Q5_no_check_out Q6_no_concave Q7_depth_first Q8_no_near_in  Q9_pick_furthest\n\
 Q10_no_narrow  Q11_trinormals\n\
\n\
 T4_trace       Tcheck_often   Tstatistics    Tverify        Tz_stdout\n\
 TFacet_log     TInput_file    TPoint_trace   TMerge_trace   TOutput_file\n\
 TRerun         TWide_trace    TVertex_stop   TCone_stop\n\
\n\
 Angle_max      Centrum_size   Error_round    Random_dist    Visible_min\n\
 Ucoplanar_max  Wide_outside\n\
";

/*-<a                             href="qh-qhull.htm#TOC"
  >-------------------------------</a><a name="main">-</a>

  main( argc, argv )
    processes the command line, calls qhull() to do the work, and exits

  design:
    initializes data structures
    reads points
    finishes initialization
    computes convex hull and other structures
    checks the result
    writes the output
    frees memory
*/
int main(int argc, char *argv[]) {
  int curlong, totlong; /* used !qh_NOmem */
  int exitcode, numpoints, dim;
  coordT *points;
  boolT ismalloc;

#if __MWERKS__ && __POWERPC__
  char inBuf[BUFSIZ], outBuf[BUFSIZ], errBuf[BUFSIZ];
  SIOUXSettings.showstatusline= false;
  SIOUXSettings.tabspaces= 1;
  SIOUXSettings.rows= 40;
  if (setvbuf (stdin, inBuf, _IOFBF, sizeof(inBuf)) < 0   /* w/o, SIOUX I/O is slow*/
  || setvbuf (stdout, outBuf, _IOFBF, sizeof(outBuf)) < 0
  || (stdout != stderr && setvbuf (stderr, errBuf, _IOFBF, sizeof(errBuf)) < 0))
    fprintf (stderr, "qhull internal warning (main): could not change stdio to fully buffered.\n");
  argc= ccommand(&argv);
#endif

  if ((argc == 1) && isatty( 0 /*stdin*/)) {
    fprintf(stdout, qh_prompt2, qh_version);
    exit(qh_ERRnone);
  }
  if (argc > 1 && *argv[1] == '-' && !*(argv[1]+1)) {
    fprintf(stdout, qh_prompta, qh_version, qh_DEFAULTbox,
		qh_promptb, qh_promptc, qh_promptd, qh_prompte);
    exit(qh_ERRnone);
  }
  if (argc >1 && *argv[1] == '.' && !*(argv[1]+1)) {
    fprintf(stdout, qh_prompt3, qh_version);
    exit(qh_ERRnone);
  }
  qh_init_A (stdin, stdout, stderr, argc, argv);  /* sets qh qhull_command */
  exitcode= setjmp (qh errexit); /* simple statement for CRAY J916 */
  if (!exitcode) {
    qh_initflags (qh qhull_command);
    points= qh_readpoints (&numpoints, &dim, &ismalloc);
    qh_init_B (points, numpoints, dim, ismalloc);
    qh_qhull();
    qh_check_output();
    qh_produce_output();
    if (qh VERIFYoutput && !qh FORCEoutput && !qh STOPpoint && !qh STOPcone)
      qh_check_points();
    exitcode= qh_ERRnone;
  }
  qh NOerrexit= True;  /* no more setjmp */
#ifdef qh_NOmem
  qh_freeqhull( True);
#else
  qh_freeqhull( False);
  qh_memfreeshort (&curlong, &totlong);
  if (curlong || totlong)
    fprintf (stderr, "qhull internal warning (main): did not free %d bytes of long memory (%d pieces)\n",
       totlong, curlong);
#endif
  return exitcode;
} /* main */