File: plot-constellations.c

package info (click to toggle)
astrometry.net 0.98%2Bdfsg-1
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid
  • size: 19,428 kB
  • sloc: ansic: 165,791; python: 18,438; makefile: 1,560; sh: 157; cpp: 78; pascal: 67; awk: 56; perl: 9
file content (1051 lines) | stat: -rw-r--r-- 34,246 bytes parent folder | download | duplicates (3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
/*
 # This file is part of the Astrometry.net suite.
 # Licensed under a 3-clause BSD style license - see LICENSE
 */

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <math.h>
#include <sys/types.h>
#include <string.h>
#include <ctype.h>
#include <assert.h>

#include <cairo.h>

#include "an-bool.h"
#include "sip_qfits.h"
#include "starutil.h"
#include "bl.h"
#include "bl-sort.h"
#include "xylist.h"
#include "rdlist.h"
#include "boilerplate.h"
#include "mathutil.h"
#include "cairoutils.h"
#include "openngc.h"
#include "constellations.h"
#include "constellation-boundaries.h"
#include "brightstars.h"
#include "hd.h"
#include "fitsioutils.h"
#include "sip-utils.h"
#include "errors.h"
#include "log.h"

const char* OPTIONS = "hi:o:w:W:H:s:NCBpb:cjxvLn:f:MDd:G:g:JF:V:O:";

void print_help(char* progname) {
    BOILERPLATE_HELP_HEADER(stdout);
    printf("\nUsage: %s\n"
           "   -w <WCS input file>\n"
           "   ( -L: just list the items in the field\n"
           " OR  -o <image output file; \"-\" for stdout>  )\n"
           "   [-p]: write PPM output - default is PNG\n"
           "   (  [-i <PPM input file>]\n"
           "   OR [-W <width> -H <height>] )\n"
           "   [-s <scale>]: scale image coordinates by this value before plotting.\n"
           "   [-N]: plot NGC objects\n"
           "   [-F <fraction>]: minimum NGC size, relative to image size (default 0.02)\n"
           "   [-C]: plot constellations\n"
           "   [-B]: plot named bright stars\n"
           "   [-D]: plot HD objects\n"
           "   [-d]: path to HD catalog\n"
           "   [-b <number-of-bright-stars>]: just plot the <N> brightest stars\n"
           "   [-c]: only plot bright stars that have common names.\n"
           "   [-j]: if a bright star has a common name, only print that\n"
           "   [-x]: plot only white text"
           "   [-v]: be verbose\n"
           "   [-n <width>]: NGC circle width (default 2)\n"
           "   [-f <size>]: font size.\n"
           "   [-M]: show only NGC/IC and Messier numbers (no common names)\n"
           "   [-G <grid spacing in arcmin>]: plot RA,Dec grid\n"
           "   [-g <r:g:b>]: grid color (default 0.2:0.2:0.2)\n"
           "   [-J]: print JSON output to stderr\n"
           "   [-V]: vertical alignment of text labels, \"C\"enter/\"T\"op/\"B\"ottom: default C\n"
           "   [-O]: horizontal alignment of text labels, \"L\"eft/\"C\"enter/\"R\"ight, default L\n"
           "\n", progname);
}


static int sort_by_mag(const void* v1, const void* v2) {
    const brightstar_t* s1 = v1;
    const brightstar_t* s2 = v2;
    if (s1->Vmag > s2->Vmag)
        return 1;
    if (s1->Vmag == s2->Vmag)
        return 0;
    return -1;
}

struct cairos_t {
    cairo_t* fg;
    cairo_t* bg;
    cairo_t* shapes;
    cairo_t* shapesmask;
    int imgW;
    int imgH;
};
typedef struct cairos_t cairos_t;

static void add_text(cairos_t* cairos,
                     const char* txt, double px, double py,
                     char halign, char valign) {
    cairo_text_extents_t textents;
    double l,r,t,b;
    double margin = 2.0;
    int dx, dy;

    float offset = 15.;

    cairo_text_extents(cairos->fg, txt, &textents);
    l = px + textents.x_bearing;
    r = l + textents.width + textents.x_bearing;
    t = py + textents.y_bearing;
    b = t + textents.height;
    l -= margin;
    t -= margin;
    r += margin + 1;
    b += margin + 1;

    switch (valign) {
    case 'T':
        py -= (0.5 * textents.y_bearing);
        break;
    case 'B':
        py += (0.5 * textents.y_bearing) - offset;
        break;
    case 'C':
        break;
    }

    //logverb("halign=%c, width=%f\n", halign, textents.width);
    switch (halign) {
    case 'L':
        break;
    case 'C':
        px -= (0.5 * textents.width);
        break;
    case 'R':
        px -= (1.0 * textents.width);
        break;
    }


    // move text away from the edges of the image.
    if (l < 0) {
        px += -l;
        l = 0;
    }
    if (t < 0) {
        py += -t;
        t = 0;
    }
    if (r > cairos->imgW) {
        px -= (r - cairos->imgW);
        r = cairos->imgW;
    }
    if (b > cairos->imgH) {
        py -= (b - cairos->imgH);
        b = cairos->imgH;
    }
        
    // draw black text behind the white text, on the foreground layer.
    cairo_save(cairos->fg);
    cairo_set_source_rgba(cairos->fg, 0, 0, 0, 1);
    for (dy=-1; dy<=1; dy++) {
        for (dx=-1; dx<=1; dx++) {
            cairo_move_to(cairos->fg, px+dx, py+dy);
            cairo_show_text(cairos->fg, txt);
            cairo_stroke(cairos->fg);
        }
    }
    cairo_restore(cairos->fg);

    // draw the white text.
    cairo_move_to(cairos->fg, px, py);
    cairo_show_text(cairos->fg, txt);
    cairo_stroke(cairos->fg);

    // blank out anything on the lower layers underneath the text.
    cairo_save(cairos->shapesmask);
    cairo_set_source_rgba(cairos->shapesmask, 0, 0, 0, 0);
    cairo_set_operator(cairos->shapesmask, CAIRO_OPERATOR_SOURCE);
    cairo_move_to(cairos->shapesmask, l, t);
    cairo_line_to(cairos->shapesmask, l, b);
    cairo_line_to(cairos->shapesmask, r, b);
    cairo_line_to(cairos->shapesmask, r, t);
    cairo_close_path(cairos->shapesmask);
    cairo_fill(cairos->shapesmask);
    cairo_stroke(cairos->shapesmask);
    cairo_restore(cairos->shapesmask);

}

static void color_for_radec(double ra, double dec, float* r, float* g, float* b) {
    int con = constellation_containing(ra, dec);
    srand(con);
    *r = ((rand() % 128) + 127) / 255.0;
    *g = ((rand() % 128) + 127) / 255.0;
    *b = ((rand() % 128) + 127) / 255.0;
}



int main(int argc, char** args) {
    int c;
    char* wcsfn = NULL;
    char* outfn = NULL;
    char* infn = NULL;
    sip_t sip;
    double scale = 1.0;
    anbool pngformat = TRUE;

    char* hdpath = NULL;
    anbool HD = FALSE;

    cairos_t thecairos;
    cairos_t* cairos = &thecairos;

    cairo_surface_t* target = NULL;
    cairo_t* cairot = NULL;

    cairo_surface_t* surfbg = NULL;
    cairo_t* cairobg = NULL;

    cairo_surface_t* surfshapes = NULL;
    cairo_t* cairoshapes = NULL;

    cairo_surface_t* surfshapesmask = NULL;
    cairo_t* cairoshapesmask = NULL;

    cairo_surface_t* surffg = NULL;
    cairo_t* cairo = NULL;

    double lw = 2.0;
    // circle linewidth.
    double cw = 2.0;

    double ngc_fraction = 0.02;

    // NGC linewidth
    double nw = 2.0;

    // leave a gap short of connecting the points.
    double endgap = 5.0;
    // circle radius.
    double crad = endgap;

    double fontsize = 14.0;

    double label_offset = 15.0;

    int W = 0, H = 0;
    unsigned char* img = NULL;

    anbool NGC = FALSE, constell = FALSE;
    anbool bright = FALSE;
    anbool common_only = FALSE;
    anbool print_common_only = FALSE;
    int Nbright = 0;
    double ra, dec, px, py;
    int i, N;
    anbool justlist = FALSE;
    anbool only_messier = FALSE;

    anbool grid = FALSE;
    double gridspacing = 0.0;
    double gridcolor[3] = { 0.2, 0.2, 0.2 };

    int loglvl = LOG_MSG;

    char halign = 'L';
    char valign = 'C';
    sl* json = NULL;

    anbool whitetext = FALSE;

    while ((c = getopt(argc, args, OPTIONS)) != -1) {
        switch (c) {
        case 'V':
            valign = optarg[0];
            break;
        case 'O':
            halign = optarg[0];
            break;
        case 'F':
            ngc_fraction = atof(optarg);
            break;
        case 'h':
            print_help(args[0]);
            exit(0);
        case 'J':
            json = sl_new(4);
            break;
        case 'G':
            gridspacing = atof(optarg);
            break;
        case 'g':
            {
                char *tail = NULL;
                gridcolor[0] = strtod(optarg,&tail);
                if (*tail) { tail++; gridcolor[1] = strtod(tail,&tail); }
                if (*tail) { tail++; gridcolor[2] = strtod(tail,&tail); }
            }
            break;
        case 'D':
            HD = TRUE;
            break;
        case 'd':
            hdpath = optarg;
            break;
        case 'M':
            only_messier = TRUE;
            break;
        case 'n':
            nw = atof(optarg);
            break;
        case 'f':
            fontsize = atof(optarg);
            break;
        case 'L':
            justlist = TRUE;
            outfn = NULL;
            break;
        case 'x':
            whitetext = TRUE;
            break;
        case 'v':
            loglvl++;
            break;
            break;
        case 'j':
            print_common_only = TRUE;
            break;
        case 'c':
            common_only = TRUE;
            break;
        case 'b':
            Nbright = atoi(optarg);
            break;
        case 'B':
            bright = TRUE;
            break;
        case 'N':
            NGC = TRUE;
            break;
        case 'C':
            constell = TRUE;
            break;
        case 'p':
            pngformat = FALSE;
            break;
        case 's':
            scale = atof(optarg);
            break;
        case 'o':
            outfn = optarg;
            break;
        case 'i':
            infn = optarg;
            break;
        case 'w':
            wcsfn = optarg;
            break;
        case 'W':
            W = atoi(optarg);
            break;
        case 'H':
            H = atoi(optarg);
            break;
        }
    }

    log_init(loglvl);
    log_to(stderr);
    fits_use_error_system();

    if (optind != argc) {
        print_help(args[0]);
        exit(-1);
    }

    if (!(outfn || justlist) || !wcsfn) {
        logerr("Need (-o or -L) and -w args.\n");
        print_help(args[0]);
        exit(-1);
    }

    // read WCS.
    logverb("Trying to parse SIP/TAN header from %s...\n", wcsfn);
    if (!file_exists(wcsfn)) {
        ERROR("No such file: \"%s\"", wcsfn);
        exit(-1);
    }
    if (sip_read_header_file(wcsfn, &sip)) {
        logverb("Got SIP header.\n");
    } else {
        ERROR("Failed to parse SIP/TAN header from %s", wcsfn);
        exit(-1);
    }

    if (!(NGC || constell || bright || HD || grid)) {
        logerr("Neither constellations, bright stars, HD nor NGC/IC overlays selected!\n");
        print_help(args[0]);
        exit(-1);
    }

    if (gridspacing > 0.0)
        grid = TRUE;

    // adjust for scaling...
    lw /= scale;
    cw /= scale;
    nw /= scale;
    crad /= scale;
    endgap /= scale;
    fontsize /= scale;
    label_offset /= scale;

    if (!W || !H) {
        W = sip.wcstan.imagew;
        H = sip.wcstan.imageh;
    }
    if (!(infn || (W && H))) {
        logerr("Image width/height unspecified, and no input image given.\n");
        exit(-1);
    }


    if (infn) {
        cairoutils_fake_ppm_init();
        img = cairoutils_read_ppm(infn, &W, &H);
        if (!img) {
            ERROR("Failed to read input image %s", infn);
            exit(-1);
        }
        cairoutils_rgba_to_argb32(img, W, H);
    } else if (!justlist) {
        // Allocate a black image.
        img = calloc(4 * W * H, 1);
        if (!img) {
            SYSERROR("Failed to allocate a blank image on which to plot!");
            exit(-1);
        }
    }

    if (HD && !hdpath) {
        logerr("If you specify -D (plot Henry Draper objs), you also have to give -d (path to Henry Draper catalog)\n");
        exit(-1);
    }

    if (!justlist) {
        /*
         Cairo layers:

         -background: surfbg / cairobg
         --> gets drawn first, in black, masked by surfshapesmask

         -shapes: surfshapes / cairoshapes
         --> gets drawn second, masked by surfshapesmask

         -foreground/text: surffg / cairo
         --> gets drawn last.
         */
        surffg = cairo_image_surface_create(CAIRO_FORMAT_ARGB32, W, H);
        cairo = cairo_create(surffg);
        cairo_set_line_join(cairo, CAIRO_LINE_JOIN_BEVEL);
        cairo_set_antialias(cairo, CAIRO_ANTIALIAS_GRAY);
        cairo_set_source_rgba(cairo, 1.0, 1.0, 1.0, 1.0);
        cairo_scale(cairo, scale, scale);
        //cairo_select_font_face(cairo, "helvetica", CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_BOLD);
        cairo_select_font_face(cairo, "DejaVu Sans Mono Book", CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_BOLD);
        cairo_set_font_size(cairo, fontsize);

        surfshapes = cairo_image_surface_create(CAIRO_FORMAT_ARGB32, W, H);
        cairoshapes = cairo_create(surfshapes);
        cairo_set_line_join(cairoshapes, CAIRO_LINE_JOIN_BEVEL);
        cairo_set_antialias(cairoshapes, CAIRO_ANTIALIAS_GRAY);
        cairo_set_source_rgba(cairoshapes, 1.0, 1.0, 1.0, 1.0);
        cairo_scale(cairoshapes, scale, scale);
        cairo_select_font_face(cairoshapes, "DejaVu Sans Mono Book", CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_BOLD);
        cairo_set_font_size(cairoshapes, fontsize);

        surfshapesmask = cairo_image_surface_create(CAIRO_FORMAT_A8, W, H);
        cairoshapesmask = cairo_create(surfshapesmask);
        cairo_set_line_join(cairoshapesmask, CAIRO_LINE_JOIN_BEVEL);
        cairo_set_antialias(cairoshapesmask, CAIRO_ANTIALIAS_GRAY);
        cairo_set_source_rgba(cairoshapesmask, 1.0, 1.0, 1.0, 1.0);
        cairo_scale(cairoshapesmask, scale, scale);
        cairo_select_font_face(cairoshapesmask, "DejaVu Sans Mono Book", CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_BOLD);
        cairo_set_font_size(cairoshapesmask, fontsize);
        cairo_paint(cairoshapesmask);
        cairo_stroke(cairoshapesmask);

        surfbg = cairo_image_surface_create(CAIRO_FORMAT_A8, W, H);
        cairobg = cairo_create(surfbg);
        cairo_set_line_join(cairobg, CAIRO_LINE_JOIN_BEVEL);
        cairo_set_antialias(cairobg, CAIRO_ANTIALIAS_GRAY);
        cairo_set_source_rgba(cairobg, 0, 0, 0, 1);
        cairo_scale(cairobg, scale, scale);
        cairo_select_font_face(cairobg, "DejaVu Sans Mono Book", CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_BOLD);
        cairo_set_font_size(cairobg, fontsize);

        cairos->bg = cairobg;
        cairos->fg = cairo;
        cairos->shapes = cairoshapes;
        cairos->shapesmask = cairoshapesmask;
        cairos->imgW = (float)W/scale;
        cairos->imgH = (float)H/scale;
        //    }

        if (grid) {
            double ramin, ramax, decmin, decmax;
            double ra, dec;
            double rastep = gridspacing / 60.0;
            double decstep = gridspacing / 60.0;
            // how many line segments
            int N = 10;
            double px, py;
            int i;

            cairo_set_source_rgba(cairo, gridcolor[0], gridcolor[1], gridcolor[2], 1.0);

            sip_get_radec_bounds(&sip, 100, &ramin, &ramax, &decmin, &decmax);
            logverb("Plotting grid lines from RA=%g to %g in steps of %g; Dec=%g to %g in steps of %g\n",
                    ramin, ramax, rastep, decmin, decmax, decstep);
            for (dec = decstep * floor(decmin / decstep); dec<=decmax; dec+=decstep) {
                logverb("  dec=%g\n", dec);
                for (i=0; i<=N; i++) {
                    ra = ramin + ((double)i / (double)N) * (ramax - ramin);
                    if (!sip_radec2pixelxy(&sip, ra, dec, &px, &py))
                        continue;
                    // first time, move_to; else line_to
                    ((ra == ramin) ? cairo_move_to : cairo_line_to)(cairo, px, py);
                }
                cairo_stroke(cairo);
            }
            for (ra = rastep * floor(ramin / rastep); ra <= ramax; ra += rastep) {
                //for (dec=decmin; dec<=decmax; dec += (decmax - decmin)/(double)N) {
                logverb("  ra=%g\n", ra);
                for (i=0; i<=N; i++) {
                    dec = decmin + ((double)i / (double)N) * (decmax - decmin);
                    if (!sip_radec2pixelxy(&sip, ra, dec, &px, &py))
                        continue;
                    // first time, move_to; else line_to
                    ((dec == decmin) ? cairo_move_to : cairo_line_to)(cairo, px, py);
                }
                cairo_stroke(cairo);
            }

            cairo_set_source_rgba(cairo, 1.0, 1.0, 1.0, 1.0);
        }
    }

    if (constell) {
        N = constellations_n();

        logverb("Checking %i constellations.\n", N);
        for (c=0; c<N; c++) {
            const char* shortname = NULL;
            const char* longname;
            il* lines;
            il* uniqstars;
            il* inboundstars;
            float r,g,b;
            int Ninbounds;
            int Nunique;
            cairo_text_extents_t textents;
            double cmass[3];

            uniqstars = constellations_get_unique_stars(c);
            inboundstars = il_new(16);

            Nunique = il_size(uniqstars);
            debug("%s: %zu unique stars.\n", shortname, il_size(uniqstars));

            // Count the number of unique stars belonging to this contellation
            // that are within the image bounds
            Ninbounds = 0;
            for (i=0; i<il_size(uniqstars); i++) {
                int star;
                star = il_get(uniqstars, i);
                constellations_get_star_radec(star, &ra, &dec);
                debug("star %i: ra,dec (%g,%g)\n", il_get(uniqstars, i), ra, dec);
                if (!sip_radec2pixelxy(&sip, ra, dec, &px, &py))
                    continue;
                if (px < 0 || py < 0 || px*scale > W || py*scale > H)
                    continue;
                Ninbounds++;
                il_append(inboundstars, star);
            }
            il_free(uniqstars);
            debug("%i are in-bounds.\n", Ninbounds);
            // Only draw this constellation if at least 2 of its stars
            // are within the image bounds.
            if (Ninbounds < 2) {
                il_free(inboundstars);
                continue;
            }

            // Set the color based on the location of the first in-bounds star.
            // This is a hack -- we have two different constellation
            // definitions with different numbering schemes!
            if (!justlist && (il_size(inboundstars) > 0)) {
                // This is helpful for videos: ensuring that the same
                // color is chosen for a constellation in each frame.
                int star = il_get(inboundstars, 0);
                constellations_get_star_radec(star, &ra, &dec);
                if (whitetext) {
                    r = g = b = 1;
                } else {
                    color_for_radec(ra, dec, &r, &g, &b);
                }
                cairo_set_source_rgba(cairoshapes, r,g,b,0.8);
                cairo_set_line_width(cairoshapes, cw);
                cairo_set_source_rgba(cairo, r,g,b,0.8);
                cairo_set_line_width(cairo, cw);
            }

            // Draw circles around each star.
            // Find center of mass (of the in-bounds stars)
            cmass[0] = cmass[1] = cmass[2] = 0.0;
            for (i=0; i<il_size(inboundstars); i++) {
                double xyz[3];
                int star = il_get(inboundstars, i);
                constellations_get_star_radec(star, &ra, &dec);
                if (!sip_radec2pixelxy(&sip, ra, dec, &px, &py))
                    continue;
                if (px < 0 || py < 0 || px*scale > W || py*scale > H)
                    continue;
                if (!justlist) {
                    cairo_arc(cairobg, px, py, crad+1.0, 0.0, 2.0*M_PI);
                    cairo_stroke(cairobg);
                    cairo_arc(cairoshapes, px, py, crad, 0.0, 2.0*M_PI);
                    cairo_stroke(cairoshapes);
                }
                radecdeg2xyzarr(ra, dec, xyz);
                cmass[0] += xyz[0];
                cmass[1] += xyz[1];
                cmass[2] += xyz[2];
            }
            cmass[0] /= il_size(inboundstars);
            cmass[1] /= il_size(inboundstars);
            cmass[2] /= il_size(inboundstars);
            xyzarr2radecdeg(cmass, &ra, &dec);

            il_free(inboundstars);

            if (!sip_radec2pixelxy(&sip, ra, dec, &px, &py))
                continue;

            shortname = constellations_get_shortname(c);
            longname = constellations_get_longname(c);
            assert(shortname && longname);

            logverb("%s at (%g, %g)\n", longname, px, py);

            if (Ninbounds == Nunique) {
                printf("The constellation %s (%s)\n", longname, shortname);
            } else {
                printf("Part of the constellation %s (%s)\n", longname, shortname);
            }

            if (justlist)
                continue;

            // If the label will be off-screen, move it back on.
            cairo_text_extents(cairo, shortname, &textents);
			
            if (px < 0)
                px = 0;
            if (py < textents.height)
                py = textents.height;
            if ((px + textents.width)*scale > W)
                px = W/scale - textents.width;
            if ((py+textents.height)*scale > H)
                py = H/scale - textents.height;
            logverb("%s at (%g, %g)\n", shortname, px, py);

            add_text(cairos, longname, px, py, halign, valign);

            // Draw the lines.
            cairo_set_line_width(cairo, lw);
            lines = constellations_get_lines(c);
            for (i=0; i<il_size(lines)/2; i++) {
                int star1, star2;
                double ra1, dec1, ra2, dec2;
                double px1, px2, py1, py2;
                double dx, dy;
                double dist;
                double gapfrac;
                star1 = il_get(lines, i*2+0);
                star2 = il_get(lines, i*2+1);
                constellations_get_star_radec(star1, &ra1, &dec1);
                constellations_get_star_radec(star2, &ra2, &dec2);
                if (!sip_radec2pixelxy(&sip, ra1, dec1, &px1, &py1) ||
                    !sip_radec2pixelxy(&sip, ra2, dec2, &px2, &py2))
                    continue;
                dx = px2 - px1;
                dy = py2 - py1;
                dist = hypot(dx, dy);
                gapfrac = endgap / dist;
                cairo_move_to(cairoshapes, px1 + dx*gapfrac, py1 + dy*gapfrac);
                cairo_line_to(cairoshapes, px1 + dx*(1.0-gapfrac), py1 + dy*(1.0-gapfrac));
                cairo_stroke(cairoshapes);
            }
            il_free(lines);
        }
        logverb("done constellations.\n");
    }

    if (bright) {
        double dy = 0;
        cairo_font_extents_t extents;
        pl* brightstars = pl_new(16);

        if (!justlist) {
            cairo_set_source_rgba(cairoshapes, 0.75, 0.75, 0.75, 0.8);
            cairo_font_extents(cairo, &extents);
            dy = extents.ascent * 0.5;
            cairo_set_line_width(cairoshapes, cw);
        }

        N = bright_stars_n();
        logverb("Checking %i bright stars.\n", N);

        for (i=0; i<N; i++) {
            const brightstar_t* bs = bright_stars_get(i);

            if (!sip_radec2pixelxy(&sip, bs->ra, bs->dec, &px, &py))
                continue;
            if (px < 0 || py < 0 || px*scale > W || py*scale > H)
                continue;
            if (!(bs->name && strlen(bs->name)))
                continue;
            if (common_only && !(bs->common_name && strlen(bs->common_name)))
                continue;

            if (strcmp(bs->common_name, "Maia") == 0)
                continue;

            pl_append(brightstars, bs);
        }

        // keep only the Nbright brightest?
        if (Nbright && (pl_size(brightstars) > Nbright)) {
            pl_sort(brightstars, sort_by_mag);
            pl_remove_index_range(brightstars, Nbright, pl_size(brightstars)-Nbright);
        }

        for (i=0; i<pl_size(brightstars); i++) {
            char* text;
            const brightstar_t* bs = pl_get(brightstars, i);

            if (!sip_radec2pixelxy(&sip, bs->ra, bs->dec, &px, &py))
                continue;
            if (bs->common_name && strlen(bs->common_name))
                if (print_common_only || common_only)
                    text = strdup(bs->common_name);
                else
                    asprintf_safe(&text, "%s (%s)", bs->common_name, bs->name);
            else
                text = strdup(bs->name);

            logverb("%s at (%g, %g)\n", text, px, py);

            if (json) {
                sl* names = sl_new(4);
                char* namearr;
                if (bs->common_name && strlen(bs->common_name))
                    sl_append(names, bs->common_name);
                if (bs->name)
                    sl_append(names, bs->name);
				
                namearr = sl_join(names, "\", \"");

                sl_appendf(json,
                           "{ \"type\"  : \"star\", "
                           "  \"pixelx\": %g,       "
                           "  \"pixely\": %g,       "
                           "  \"name\"  : \"%s\",   "
                           "  \"names\" : [ \"%s\" ] } "
                           , px, py,
                           (bs->common_name && strlen(bs->common_name)) ? bs->common_name : bs->name,
                           namearr);
                free(namearr);
                sl_free2(names);
            }

            if (bs->common_name && strlen(bs->common_name))
                printf("The star %s (%s)\n", bs->common_name, bs->name);
            else
                printf("The star %s\n", bs->name);

            if (!justlist) {
                float r,g,b;
                // set color based on RA,Dec to match constellations above.
                if (whitetext) {
                    r = g = b = 1;
                } else {
                    color_for_radec(bs->ra, bs->dec, &r, &g, &b);
                }
                cairo_set_source_rgba(cairoshapes, r,g,b,0.8);
                cairo_set_source_rgba(cairo, r,g,b, 0.8);
            }

            if (!justlist)
                add_text(cairos, text, px + label_offset, py + dy,
                         halign, valign);

            free(text);

            if (!justlist) {
                // plot a black circle behind the light circle...
                cairo_arc(cairobg, px, py, crad+1.0, 0.0, 2.0*M_PI);
                cairo_stroke(cairobg);

                cairo_arc(cairoshapes, px, py, crad, 0.0, 2.0*M_PI);
                cairo_stroke(cairoshapes);
            }
        }
        pl_free(brightstars);
    }

    if (NGC) {
        double imscale;
        double imsize;
        double dy = 0;
        cairo_font_extents_t extents;

        if (!justlist) {
            cairo_set_source_rgb(cairoshapes, 1.0, 1.0, 1.0);
            cairo_set_source_rgb(cairo, 1.0, 1.0, 1.0);
            cairo_set_line_width(cairo, nw);
            cairo_font_extents(cairo, &extents);
            dy = extents.ascent * 0.5;
        }

        // arcsec/pixel
        imscale = sip_pixel_scale(&sip);
        // arcmin
        imsize = imscale * (imin(W, H) / scale) / 60.0;
        N = ngc_num_entries();

        logverb("Checking %i NGC/IC objects.\n", N);

        for (i=0; i<N; i++) {
            ngc_entry* ngc = ngc_get_entry(i);
            sl* str;
            sl* names;
            double pixsize;
            char* text;
	    double tx,ty;
	    double fmargin;

            if (!ngc)
                break;
            if (ngc->size < imsize * ngc_fraction)
                continue;

            if (!sip_radec2pixelxy(&sip, ngc->ra, ngc->dec, &px, &py))
                continue;
            if (px < 0 || py < 0 || px*scale > W || py*scale > H)
                continue;

	    // Due to SIP distortions, it is possible for objects WAY outside the field to
	    // "fold" into the field.
	    // An example: /home/nova/astrometry/net/data/jobs/0700/07009522/wcs.fits
	    if (!tan_radec2pixelxy(&(sip.wcstan), ngc->ra, ngc->dec, &tx, &ty))
	      continue;
	    // margin: fraction of image size
	    fmargin = 0.1;
	    if (tx < -W*fmargin || tx*scale > (W*(1+fmargin)) ||
		ty < -H*fmargin || ty*scale > (H*(1+fmargin)))
	      continue;

            str = sl_new(4);
            //sl_appendf(str, "%s %i", (ngc->is_ngc ? "NGC" : "IC"), ngc->id);
            names = ngc_get_names(ngc, NULL);
            if (names) {
                int n;
                for (n=0; n<sl_size(names); n++) {
                    if (only_messier && strncmp(sl_get(names, n), "M ", 2))
                        continue;
                    sl_append(str, sl_get(names, n));
                }
            }
            sl_free2(names);

            text = sl_implode(str, " / ");

            printf("%s\n", text);

            pixsize = ngc->size * 60.0 / imscale;

            if (!justlist) {
                // black circle behind the white one...
                cairo_arc(cairobg, px, py, pixsize/2.0+1.0, 0.0, 2.0*M_PI);
                cairo_stroke(cairobg);

                cairo_move_to(cairoshapes, px + pixsize/2.0, py);
                cairo_arc(cairoshapes, px, py, pixsize/2.0, 0.0, 2.0*M_PI);
                debug("size: %f arcsec, pixsize: %f pixels\n", ngc->size, pixsize);
                cairo_stroke(cairoshapes);

                add_text(cairos, text, px + label_offset, py + dy,
                         halign, valign);
            }

            if (json) {
                char* namelist = sl_implode(str, "\", \"");
                sl_appendf(json,
                           "{ \"type\"   : \"ngc\", "
                           "  \"names\"  : [ \"%s\" ], "
                           "  \"pixelx\" : %g, "
                           "  \"pixely\" : %g, "
                           "  \"radius\" : %g }"
                           , namelist, px, py, pixsize/2.0);
                free(namelist);
            }

            free(text);
            sl_free2(str);
        }
    }

    if (HD) {
        double rac, decc, ra2, dec2;
        double arcsec;
        hd_catalog_t* hdcat;
        bl* hdlist;
        int i;

        if (!justlist)
            cairo_set_source_rgb(cairo, 1.0, 1.0, 1.0);

        logverb("Reading HD catalog: %s\n", hdpath);
        hdcat = henry_draper_open(hdpath);
        if (!hdcat) {
            ERROR("Failed to open HD catalog");
            exit(-1);
        }
        logverb("Got %i HD stars\n", henry_draper_n(hdcat));

        sip_pixelxy2radec(&sip, W/(2.0*scale), H/(2.0*scale), &rac, &decc);
        sip_pixelxy2radec(&sip, 0.0, 0.0, &ra2, &dec2);
        arcsec = arcsec_between_radecdeg(rac, decc, ra2, dec2);
        // Fudge
        arcsec *= 1.1;
        hdlist = henry_draper_get(hdcat, rac, decc, arcsec);
        logverb("Found %zu HD stars within range (%g arcsec of RA,Dec %g,%g)\n", bl_size(hdlist), arcsec, rac, decc);

        for (i=0; i<bl_size(hdlist); i++) {
            double px, py;
            char* txt;
            hd_entry_t* hd = bl_access(hdlist, i);
            if (!sip_radec2pixelxy(&sip, hd->ra, hd->dec, &px, &py)) {
                continue;
            }
            if (px < 0 || py < 0 || px*scale > W || py*scale > H) {
                logverb("  HD %i at RA,Dec (%g, %g) -> pixel (%.1f, %.1f) is out of bounds\n",
                        hd->hd, hd->ra, hd->dec, px, py);
                continue;
            }
            asprintf_safe(&txt, "HD %i", hd->hd);
            if (!justlist) {
                cairo_text_extents_t textents;
                cairo_text_extents(cairo, txt, &textents);
                cairo_arc(cairobg, px, py, crad+1.0, 0.0, 2.0*M_PI);
                cairo_stroke(cairobg);
                cairo_arc(cairoshapes, px, py, crad, 0.0, 2.0*M_PI);
                cairo_stroke(cairoshapes);

                px -= (textents.width * 0.5);
                py -= (crad + 4.0);

                add_text(cairos, txt, px, py, halign, valign);
            }

            if (json)
                sl_appendf(json,
                           "{ \"type\"  : \"hd\","
                           "  \"pixelx\": %g, "
                           "  \"pixely\": %g, "
                           "  \"name\"  : \"HD %i\" }"
                           , px, py, hd->hd);

            printf("%s\n", txt);
            free(txt);
        }
        bl_free(hdlist);
        henry_draper_close(hdcat);
    }

    if (json) {
        FILE* fout = stderr;
        char* annstr = sl_implode(json, ",\n");
        fprintf(fout, "{ \n");
        fprintf(fout, "  \"status\": \"solved\",\n");
        fprintf(fout, "  \"git-revision\": %s,\n", AN_GIT_REVISION);
        fprintf(fout, "  \"git-date\": \"%s\",\n", AN_GIT_DATE);
        fprintf(fout, "  \"annotations\": [\n%s\n]\n", annstr);
        fprintf(fout, "}\n");
        free(annstr);
    }
    sl_free2(json);
    json = NULL;

    if (justlist)
        return 0;

    target = cairo_image_surface_create_for_data(img, CAIRO_FORMAT_ARGB32, W, H, W*4);
    cairot = cairo_create(target);
    cairo_set_source_rgba(cairot, 0, 0, 0, 1);

    // Here's where you set the background surface's properties...
    cairo_set_source_surface(cairot, surfbg, 0, 0);
    cairo_mask_surface(cairot, surfshapesmask, 0, 0);
    cairo_stroke(cairot);

    // Add on the shapes.
    cairo_set_source_surface(cairot, surfshapes, 0, 0);
    //cairo_mask_surface(cairot, surfshapes, 0, 0);
    cairo_mask_surface(cairot, surfshapesmask, 0, 0);
    cairo_stroke(cairot);

    // Add on the foreground.
    cairo_set_source_surface(cairot, surffg, 0, 0);
    cairo_mask_surface(cairot, surffg, 0, 0);
    cairo_stroke(cairot);

    // Convert image for output...
    cairoutils_argb32_to_rgba(img, W, H);

    if (pngformat) {
        if (cairoutils_write_png(outfn, img, W, H)) {
            ERROR("Failed to write PNG");
            exit(-1);
        }
    } else {
        if (cairoutils_write_ppm(outfn, img, W, H)) {
            ERROR("Failed to write PPM");
            exit(-1);
        }
    }

    cairo_surface_destroy(target);
    cairo_surface_destroy(surfshapesmask);
    cairo_surface_destroy(surffg);
    cairo_surface_destroy(surfbg);
    cairo_surface_destroy(surfshapes);
    cairo_destroy(cairo);
    cairo_destroy(cairot);
    cairo_destroy(cairobg);
    cairo_destroy(cairoshapes);
    cairo_destroy(cairoshapesmask);
    free(img);

    return 0;
}