summaryrefslogtreecommitdiff
path: root/Build/source/texk/dvipdfm-x/spc_tpic.c
blob: 31d28972574b3f101d6601afed179e5ea51cc658 (plain)
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
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
/* This is dvipdfmx, an eXtended version of dvipdfm by Mark A. Wicks.

    Copyright (C) 2002-2020 by Jin-Hwan Cho and Shunsaku Hirata,
    the dvipdfmx project team.
    
    Copyright (C) 1998, 1999 by Mark A. Wicks <mwicks@kettering.edu>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.
    
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
    
    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "system.h"
#include "mem.h"
#include "error.h"

#include "numbers.h"
#include "dpxutil.h"

#include "pdfdoc.h"

#include "pdfdraw.h"
#include "pdfdev.h"

#include "specials.h"
#include "spc_tpic.h"

#define  DEBUG 1
#define  ENABLE_SPC_NAMESPACE 1

/*
 * Following "constant" converts milli-inches to
 * device (in this case PDF stream) coordinates.
 */

#define MI2DEV (0.072/pdf_dev_scale())

/*
 * Value for 'sh' command 'g' is interpreted as
 * 
 *   gray color value 1-g for "solid"
 *   opacity value g for "opacity"
 *   shape value g for "shape"
 */
#define TPIC_MODE__FILL_SOLID   0
#define TPIC_MODE__FILL_OPACITY 1
#define TPIC_MODE__FILL_SHAPE   2

#ifndef ISBLANK
#  define ISBLANK(c) ( (c) == ' ' || (c) == '\t' )
#endif

static void
skip_blank (const char **pp, const char *endptr)
{
  const char  *p = *pp;
  for ( ; p < endptr && ISBLANK(*p); p++);
  *pp = p;
}

struct spc_tpic_
{
  struct {
    int   fill;
  } mode;

  /* state */
  double     pen_size;
  int        fill_shape; /* boolean */
  double     fill_color;

  pdf_coord *points;
  int        num_points;
  int        max_points;
};

#if  1
static struct spc_tpic_ _tpic_state;
#endif

/* We use pdf_doc_add_page_content() here
 * since we always draw isolated graphics.
 */
static void
tpic__clear (struct spc_tpic_ *tp) 
{
  if (tp->points) {
    RELEASE(tp->points);
    tp->points = NULL;
  }
  tp->num_points = 0;
  tp->max_points = 0;
  tp->fill_shape = 0;
  tp->fill_color = 0.0;
}


static pdf_obj *
create_xgstate (double a /* alpha */, int f_ais /* alpha is shape */)
{
  pdf_obj  *dict;

  dict = pdf_new_dict();
  pdf_add_dict(dict,
               pdf_new_name("Type"),
               pdf_new_name("ExtGState"));
  if (f_ais) {
    pdf_add_dict(dict,
                 pdf_new_name("AIS"),
                 pdf_new_boolean(1));
  }
  pdf_add_dict(dict,
               pdf_new_name("ca"),
               pdf_new_number(a));

  return  dict;
}

static int
check_resourcestatus (const char *category, const char *resname)
{
  pdf_obj  *dict1, *dict2;

  dict1 = pdf_doc_current_page_resources();
  if (!dict1)
    return  0;

  dict2 = pdf_lookup_dict(dict1, category);
  if (dict2 &&
      pdf_obj_typeof(dict2) == PDF_DICT) {
    if (pdf_lookup_dict(dict2, resname))
      return  1;
  }
  return  0;
}

static int
set_linestyle (double pn, double da)
{
  double  dp[2]; /* dash pattern */

  pdf_dev_setlinejoin(1);
  pdf_dev_setmiterlimit(1.4);
  pdf_dev_setlinewidth(pn);
  if (da > 0.0) {
    dp[0] =  da * 72.0;
    pdf_dev_setdash(1, dp, 0);
    pdf_dev_setlinecap(0);
  } else if (da < 0.0) {
    dp[0] =  pn;
    dp[1] = -da * 72.0;
    pdf_dev_setdash(2, dp, 0);
    pdf_dev_setlinecap(1);
  } else {
    pdf_dev_setlinecap(0);
  }

  return  0;
}

static int
set_fillstyle (double g, double a, int f_ais)
{
  pdf_obj *dict;
  char     resname[32];
  char     buf[256];
  int      alp, len = 0;

  if (a > 0.0) {
    alp = round(100.0 * a);
    sprintf(resname, "_Tps_a%03d_", alp);
    if (!check_resourcestatus("ExtGState", resname)) {
      dict = create_xgstate(ROUND(0.01 * alp, 0.01), f_ais);
      pdf_doc_add_page_resource("ExtGState",
                                resname, pdf_ref_obj(dict));
      pdf_release_obj(dict);
    }
    len += sprintf(buf + len, " /%s gs", resname);

    pdf_doc_add_page_content(buf, len);  /* op: gs */
  }

  {
    pdf_color *sc, *fc, new_fc;

    pdf_color_get_current (&sc, &fc); /* get stroking and fill colors */
    pdf_color_brighten_color(&new_fc, fc, g);
    pdf_dev_set_nonstrokingcolor(&new_fc);
  }

  return  0;
}

static void
set_styles (struct spc_tpic_ *tp,
	    const pdf_coord  *c,
	    int               f_fs,
	    int               f_vp,
	    double            pn,
	    double            da) {
  pdf_tmatrix M;

  pdf_setmatrix (&M, 1.0, 0.0, 0.0, -1.0, c->x, c->y);
  pdf_dev_concat(&M);

  if (f_vp)
    set_linestyle(pn, da);

  if (f_fs) {
    double g, a;
    int f_ais;

    if (tp->mode.fill == TPIC_MODE__FILL_SOLID || !tp->fill_color) {
      g = 1.0 - tp->fill_color;
      a = 0.0;
    } else {
      g = 0.0;
      a = tp->fill_color;
    }

    f_ais = (tp->mode.fill == TPIC_MODE__FILL_SHAPE) ? 1 : 0;

    set_fillstyle(g, a, f_ais);
  }
}

static void
showpath (int f_vp, int f_fs) /* visible_path, fill_shape */
{
  if (f_vp) {
    if (f_fs)
      pdf_dev_flushpath('b', PDF_FILL_RULE_NONZERO);
    else {
      pdf_dev_flushpath('S', PDF_FILL_RULE_NONZERO);
    }
  } else {
    /*
     * Acrobat claims 'Q' as illegal operation when there are unfinished
     * path (a path without path-painting operator applied)?
     */
    if (f_fs)
      pdf_dev_flushpath('f', PDF_FILL_RULE_NONZERO);
    else {
      pdf_dev_newpath();
    }
  }
}

#define CLOSED_PATH(s) (\
  (s)->points[0].x == (s)->points[(s)->num_points-1].x && \
  (s)->points[0].y == (s)->points[(s)->num_points-1].y \
)

static int
tpic__polyline (struct spc_tpic_ *tp,
                const pdf_coord  *c,
                int               f_vp,
                double            da)
{
  double       pn    = tp->pen_size;
  int          f_fs  = tp->fill_shape;
  int          i, error = 0;

  /* Shading is applied only to closed path. */
  f_fs  = CLOSED_PATH(tp) ? f_fs : 0;
  f_vp  = (pn > 0.0) ? f_vp : 0;

  if (f_vp || f_fs) {
    pdf_dev_gsave();

    set_styles(tp, c, f_fs, f_vp, pn, da);

    pdf_dev_moveto(tp->points[0].x, tp->points[0].y);
    for (i = 0; i < tp->num_points; i++)
      pdf_dev_lineto(tp->points[i].x, tp->points[i].y);

    showpath(f_vp, f_fs);

    pdf_dev_grestore();
  }

  tpic__clear(tp);

  return  error;
}

/*
 * Accroding to
 * "Tpic: Pic for TEX", Tim Morgan, Original by Brian Kernighan, p.20:
 * 
 *  A spline is a smooth curve guided by a set of straight lines just
 *  like the line above. It begins at the same place, ends at the same
 *  place, and in between is tangent to the mid-point of each guiding
 *  line. The syntax for a spline is identical to a (path) line except
 *  for using spline instead of line.
 *
 * Spline is not a curve drawn by spline-fitting points p0, p1, ..., pn,
 * defined by tpic special "pa" command. Instead, a path defined by set
 * of points p0, p1, ... is guiding line mentioned above.
 *
 * Dvipsk draws them as a straight line from p0 to q1 = (p0 + p1)/2,
 * followed by a quadratic B-spline curve with starting point q1, (off-
 * curve) control point p1, end point q2 = (p1 + p2)/2, ..., and a
 * straight line from qn to pn.
 */

static int
tpic__spline (struct spc_tpic_ *tp,
              const pdf_coord  *c,
              int               f_vp,
              double            da)
{
  double       v[6];
  double       pn    = tp->pen_size;
  int          f_fs  = tp->fill_shape;
  int          i, error = 0;

  f_fs  = CLOSED_PATH(tp) ? f_fs : 0;
  f_vp  = (pn > 0.0) ? f_vp : 0;

  if (f_vp || f_fs) {
    pdf_dev_gsave();

    set_styles(tp, c, f_fs, f_vp, pn, da);

    pdf_dev_moveto(tp->points[0].x, tp->points[0].y);

    v[0] = 0.5 * (tp->points[0].x + tp->points[1].x);
    v[1] = 0.5 * (tp->points[0].y + tp->points[1].y);
    pdf_dev_lineto(v[0], v[1]);
    for (i = 1; i < tp->num_points - 1; i++) {
      /* B-spline control points */
      v[0] = 0.5 * (tp->points[i-1].x + tp->points[i].x);
      v[1] = 0.5 * (tp->points[i-1].y + tp->points[i].y);
      v[2] = tp->points[i].x;
      v[3] = tp->points[i].y;
      v[4] = 0.5 * (tp->points[i].x + tp->points[i+1].x);
      v[5] = 0.5 * (tp->points[i].y + tp->points[i+1].y);
      pdf_dev_bspline(v[0], v[1], v[2], v[3], v[4], v[5]);
    }
    pdf_dev_lineto(tp->points[i].x, tp->points[i].y);

    showpath(f_vp, f_fs);

    pdf_dev_grestore();
  }
  tpic__clear(tp);

  return  error;
}

static int
tpic__arc (struct spc_tpic_ *tp,
           const pdf_coord  *c,
           int               f_vp,
           double            da,
           double           *v /* 6 numbers */ )
{
  double       pn    = tp->pen_size;
  int          f_fs  = tp->fill_shape;

  f_fs  = (round(fabs(v[4] - v[5]) + 0.5) >= 360) ? f_fs : 0;
  f_vp  = (pn > 0.0) ? f_vp : 0;

  if (f_vp || f_fs) {
    pdf_dev_gsave();

    set_styles(tp, c, f_fs, f_vp, pn, da);

    /* The arcx operator here draws an excess straight line from current
     * point to the starting point of the arc if they are different, as in
     * PostScript language. It may cuase an unexpected behavior when DVIPS
     * transformation command is inserted before TPIC ar command: it invokes
     * moveto and sets currentpoint which may be different from the starting
     * point of arc to be drawn. We use newpath here to avoid drawing an
     * excess line. I'm not sure if it is proper TPIC implementation but this
     * seems to be DVIPS compatible behavior.
     */
    pdf_dev_newpath();
    pdf_dev_arcx(v[0], v[1], v[2], v[3], v[4], v[5], +1, 0.0);

    showpath(f_vp, f_fs);

    pdf_dev_grestore();
  }
  tpic__clear(tp);

  return  0;
}

#if  1
static int
spc_currentpoint (struct spc_env *spe, int *pg, pdf_coord *cp)
{
  *pg = 0;
  cp->x = spe->x_user;
  cp->y = spe->y_user;
  return  0;
}
#endif

static int
spc_handler_tpic_pn (struct spc_env *spe,
                     struct spc_arg *ap ) /* , void *dp) */
{
  struct spc_tpic_ *tp = &_tpic_state;
  char  *q;

  ASSERT(spe && ap && tp);

  skip_blank(&ap->curptr, ap->endptr);
  q = parse_float_decimal(&ap->curptr, ap->endptr);
  if (!q) {
    spc_warn(spe, "Invalid pen size specified?");
    return -1;
  }
  tp->pen_size = atof(q) * MI2DEV;
  RELEASE(q);

  return  0;
}

static int
spc_handler_tpic_pa (struct spc_env *spe,
                     struct spc_arg *ap ) /* , void *dp) */
{
  struct spc_tpic_ *tp = &_tpic_state;
  char   *q;
  int     i;
  double  v[2];

  ASSERT(spe && ap && tp);

  skip_blank(&ap->curptr, ap->endptr);
  for (i = 0;
       i < 2 && ap->curptr < ap->endptr; i++) {
    q = parse_float_decimal(&ap->curptr, ap->endptr);
    if (!q) {
      spc_warn(spe, "Missing numbers for TPIC \"pa\" command.");
      return  -1;
    }
    v[i] = atof(q);
    RELEASE(q);
    skip_blank(&ap->curptr, ap->endptr);
  }
  if (i != 2) {
    spc_warn(spe, "Invalid arg for TPIC \"pa\" command.");
    return  -1;
  }

  if (tp->num_points >= tp->max_points) {
    tp->max_points += 256;
    tp->points = RENEW(tp->points, tp->max_points, pdf_coord);
  }
  tp->points[tp->num_points].x = v[0] * MI2DEV;
  tp->points[tp->num_points].y = v[1] * MI2DEV;
  tp->num_points += 1;

  return  0;
}

static int
spc_handler_tpic_fp (struct spc_env *spe,
                     struct spc_arg *ap ) /* , void *dp) */
{
  struct spc_tpic_ *tp = &_tpic_state;
  pdf_coord  cp;
  int        pg;

  ASSERT(spe && ap && tp);

  if (tp->num_points <= 1) {
    spc_warn(spe, "Too few points (< 2) for polyline path.");
    return  -1;
  }

  spc_currentpoint(spe, &pg, &cp);

  return  tpic__polyline(tp, &cp, 1, 0.0);
}

static int
spc_handler_tpic_ip (struct spc_env *spe,
                     struct spc_arg *ap ) /* , void *dp) */
{
  struct spc_tpic_ *tp = &_tpic_state;
  pdf_coord  cp;
  int        pg;

  ASSERT(spe && ap && tp);

  if (tp->num_points <= 1) {
    spc_warn(spe, "Too few points (< 2) for polyline path.");
    return  -1;
  }

  spc_currentpoint(spe, &pg, &cp);

  return  tpic__polyline(tp, &cp, 0, 0.0);
}

static int
spc_handler_tpic_da (struct spc_env *spe,
                     struct spc_arg *ap ) /* , void *dp) */
{
  struct  spc_tpic_ *tp = &_tpic_state;
  char      *q;
  double     da = 0.0;
  pdf_coord  cp;
  int        pg;

  ASSERT(spe && ap && tp);

  skip_blank(&ap->curptr, ap->endptr);
  q = parse_float_decimal(&ap->curptr, ap->endptr);
  if (q) {
    da = atof(q);
    RELEASE(q);
  }
  if (tp->num_points <= 1) {
    spc_warn(spe, "Too few points (< 2) for polyline path.");
    return  -1;
  }

  spc_currentpoint(spe, &pg, &cp);

  return  tpic__polyline(tp, &cp, 1, da);
}

static int
spc_handler_tpic_dt (struct spc_env *spe,
                     struct spc_arg *ap ) /* , void *dp) */
{
  struct  spc_tpic_ *tp = &_tpic_state;
  char      *q;
  double     da = 0.0;
  pdf_coord  cp;
  int        pg;

  ASSERT(spe && ap && tp);

  skip_blank(&ap->curptr, ap->endptr);
  q = parse_float_decimal(&ap->curptr, ap->endptr);
  if (q) {
    da = -atof(q);
    RELEASE(q);
  }
  if (tp->num_points <= 1) {
    spc_warn(spe, "Too few points (< 2) for polyline path.");
    return  -1;
  }

  spc_currentpoint(spe, &pg, &cp);

  return  tpic__polyline(tp, &cp, 1, da);
}

static int
spc_handler_tpic_sp (struct spc_env *spe,
                     struct spc_arg *ap ) /* , void *dp) */
{
  struct  spc_tpic_ *tp = &_tpic_state;
  char      *q;
  double     da = 0.0;
  pdf_coord  cp;
  int        pg;

  ASSERT(spe && ap && tp);

  skip_blank(&ap->curptr, ap->endptr);
  q = parse_float_decimal(&ap->curptr, ap->endptr);
  if (q) {
    da = atof(q);
    RELEASE(q);
  }
  if (tp->num_points <= 2) {
    spc_warn(spe, "Too few points (< 3) for spline path.");
    return  -1;
  }

  spc_currentpoint(spe, &pg, &cp);

  return  tpic__spline(tp, &cp, 1, da);
}

static int
spc_handler_tpic_ar (struct spc_env *spe,
                     struct spc_arg *ap ) /* , void *dp) */
{
  struct  spc_tpic_ *tp = &_tpic_state;
  double     v[6];
  pdf_coord  cp;
  int        pg;
  char      *q;
  int        i;

  ASSERT(spe && ap && tp);

  skip_blank(&ap->curptr, ap->endptr);
  for (i = 0;
       i < 6 && ap->curptr < ap->endptr; i++) {
    q = parse_float_decimal(&ap->curptr, ap->endptr);
    if (!q) {
      spc_warn(spe, "Invalid args. in TPIC \"ar\" command.");
      return  -1;
    }
    v[i] = atof(q);
    RELEASE(q);
    skip_blank(&ap->curptr, ap->endptr);
  }
  if (i != 6) {
    spc_warn(spe, "Invalid arg for TPIC \"ar\" command.");
    return  -1;
  }

  v[0] *= MI2DEV; v[1] *= MI2DEV;
  v[2] *= MI2DEV; v[3] *= MI2DEV;
  v[4] *= 180.0 / M_PI;
  v[5] *= 180.0 / M_PI;

  spc_currentpoint(spe, &pg, &cp);

  return  tpic__arc(tp, &cp, 1, 0.0, v);
}

static int
spc_handler_tpic_ia (struct spc_env *spe,
                     struct spc_arg *ap ) /* , void *dp) */
{
  struct  spc_tpic_ *tp = &_tpic_state;
  double     v[6];
  pdf_coord  cp;
  int        pg;
  char      *q;
  int        i;

  ASSERT(spe && ap && tp);

  skip_blank(&ap->curptr, ap->endptr);
  for (i = 0;
       i < 6 && ap->curptr < ap->endptr; i++) {
    q = parse_float_decimal(&ap->curptr, ap->endptr);
    if (!q) {
      spc_warn(spe, "Invalid args. in TPIC \"ia\" command.");
      return  -1;
    }
    v[i] = atof(q);
    RELEASE(q);
    skip_blank(&ap->curptr, ap->endptr);
  }
  if (i != 6) {
    spc_warn(spe, "Invalid arg for TPIC \"ia\" command.");
    return  -1;
  }

  v[0] *= MI2DEV; v[1] *= MI2DEV;
  v[2] *= MI2DEV; v[3] *= MI2DEV;
  v[4] *= 180.0 / M_PI;
  v[5] *= 180.0 / M_PI;

  spc_currentpoint(spe, &pg, &cp);

  return  tpic__arc(tp, &cp, 0, 0.0, v);
}

static int
spc_handler_tpic_sh (struct spc_env *spe,
                     struct spc_arg *ap ) /* , void *dp) */
{
  struct  spc_tpic_ *tp = &_tpic_state;
  char   *q;

  ASSERT(spe && ap && tp);

  tp->fill_shape = 1;
  tp->fill_color = 0.5;

  skip_blank(&ap->curptr, ap->endptr);
  q = parse_float_decimal(&ap->curptr, ap->endptr);
  if (q) {
    double g = atof(q);
    RELEASE(q);
    if (g >= 0.0 && g <= 1.0)
      tp->fill_color = g;
    else {
      WARN("Invalid fill color specified: %g\n", g);
      return -1;
    }      
  }

  return  0;
}

static int
spc_handler_tpic_wh (struct spc_env *spe,
                     struct spc_arg *ap ) /* , void *dp) */
{
  struct  spc_tpic_ *tp = &_tpic_state;

  ASSERT(spe && ap && tp);

  tp->fill_shape = 1;
  tp->fill_color = 0.0;

  return  0;
}

static int
spc_handler_tpic_bk (struct spc_env *spe,
                     struct spc_arg *ap ) /* , void *dp) */
{
  struct  spc_tpic_ *tp = &_tpic_state;

  ASSERT(spe && ap && tp);

  tp->fill_shape = 1;
  tp->fill_color = 1.0;

  return  0;
}

static int
spc_handler_tpic_tx (struct spc_env *spe,
                     struct spc_arg *ap ) /* , void *dp) */
{
  struct  spc_tpic_ *tp = &_tpic_state;

  ASSERT(spe && ap && tp);

  spc_warn(spe, "TPIC command \"tx\" not supported.");

  return  -1;
}


static int
spc_handler_tpic__init (struct spc_env *spe, void *dp)
{
  struct spc_tpic_ *tp = dp;

#if  0
  tp->mode.fill  = TPIC_MODE__FILL_SOLID;
#endif 
  tp->pen_size   = 1.0;
  tp->fill_shape = 0;
  tp->fill_color = 0.0;

  tp->points     = NULL;
  tp->num_points = 0;
  tp->max_points = 0;

  if (tp->mode.fill != TPIC_MODE__FILL_SOLID &&
      pdf_check_version(1, 4) < 0) {
      spc_warn(spe, "Tpic shading support requires PDF version 1.4.");
    tp->mode.fill = TPIC_MODE__FILL_SOLID;
  }

  return  0;
}

static int
spc_handler_tpic__bophook (void *dp)
{
  struct spc_tpic_ *tp = dp;

  ASSERT(tp);

  tpic__clear(tp);

  return  0;
}

static int
spc_handler_tpic__eophook (struct spc_env *spe, void *dp)
{
  struct spc_tpic_ *tp = dp;

  ASSERT(tp);

  if (tp->num_points > 0)
    spc_warn(spe, "Unflushed tpic path at end of the page.");
  tpic__clear(tp);

  return  0;
}

static int
spc_handler_tpic__clean (struct spc_env *spe, void *dp)
{
  struct spc_tpic_ *tp = dp;

  ASSERT(tp);

  if (tp->num_points > 0)
    spc_warn(spe, "Unflushed tpic path at end of the document.");

  tpic__clear(tp);
#if  0
  RELEASE(tp);
#endif

  return  0;
}

void
tpic_set_fill_mode (int mode)
{
  struct spc_tpic_ *tp = &_tpic_state;
  tp->mode.fill = mode;
}


int
spc_tpic_at_begin_page (void)
{
  struct spc_tpic_ *tp = &_tpic_state;
  return  spc_handler_tpic__bophook(tp);
}

int
spc_tpic_at_end_page (void)
{
  struct spc_tpic_ *tp = &_tpic_state;
  return  spc_handler_tpic__eophook(NULL, tp);
}


int
spc_tpic_at_begin_document (void)
{
  struct spc_tpic_ *tp = &_tpic_state;
  return  spc_handler_tpic__init(NULL, tp);
}

int
spc_tpic_at_end_document (void)
{
  struct spc_tpic_ *tp = &_tpic_state;
  return  spc_handler_tpic__clean(NULL, tp);
}


#if  DEBUG
#include "pdfparse.h" /* parse_val_ident :( */

static pdf_obj *
spc_parse_kvpairs (struct spc_arg *ap)
{
  pdf_obj *dict;
  char    *kp, *vp;
  int      error = 0;

  dict = pdf_new_dict();

  skip_blank(&ap->curptr, ap->endptr);
  while (!error && ap->curptr < ap->endptr) {
    kp = parse_val_ident(&ap->curptr, ap->endptr);
    if (!kp)
      break;
    skip_blank(&ap->curptr, ap->endptr);
    if (ap->curptr < ap->endptr &&
        ap->curptr[0] == '=') {
      ap->curptr++;
      skip_blank(&ap->curptr, ap->endptr);
      if (ap->curptr == ap->endptr) {
        RELEASE(kp);
        error = -1;
        break;
      }
      vp = parse_c_string(&ap->curptr, ap->endptr);
      if (!vp)
        error = -1;
      else {
        pdf_add_dict(dict,
                     pdf_new_name(kp),
                     pdf_new_string(vp, strlen(vp) + 1)); /* NULL terminate */
        RELEASE(vp);
      }
    } else {
      /* Treated as 'flag' */
      pdf_add_dict(dict,
                   pdf_new_name(kp),
                   pdf_new_boolean(1));
    }
    RELEASE(kp);
    if (!error)
      skip_blank(&ap->curptr, ap->endptr);
  }

  if (error) {
    pdf_release_obj(dict);
    dict = NULL;
  }

  return  dict;
}

static int
tpic_filter_getopts (pdf_obj *kp, pdf_obj *vp, void *dp)
{
  struct spc_tpic_ *tp = dp;
  char  *k, *v;
  int    error = 0;

  ASSERT( kp && vp && tp );

  k = pdf_name_value(kp);
  if (!strcmp(k, "fill-mode")) {
    if (pdf_obj_typeof(vp) != PDF_STRING) {
      WARN("Invalid value for TPIC option fill-mode...");
      error = -1;
    } else {
      v = pdf_string_value(vp);
      if (!strcmp(v, "shape"))
        tp->mode.fill = TPIC_MODE__FILL_SHAPE;
      else if (!strcmp(v, "opacity"))
        tp->mode.fill = TPIC_MODE__FILL_OPACITY;
      else if (!strcmp(v, "solid"))
        tp->mode.fill = TPIC_MODE__FILL_SOLID;
      else {
        WARN("Invalid value for TPIC option fill-mode: %s", v);
        error = -1;
      }
    }
  } else {
    WARN("Unrecognized option for TPIC special handler: %s", k);
    error = -1;
  }

  return  error;
}

static int
spc_handler_tpic__setopts (struct spc_env *spe,
                           struct spc_arg *ap)
{
  struct spc_tpic_ *tp = &_tpic_state;
  pdf_obj  *dict;
  int       error = 0;

  dict  = spc_parse_kvpairs(ap);
  if (!dict)
    return  -1;
  error = pdf_foreach_dict(dict, tpic_filter_getopts, tp);
  if (!error) {
    if (tp->mode.fill != TPIC_MODE__FILL_SOLID &&
        pdf_check_version(1, 4) < 0) {
      spc_warn(spe, "Transparent fill mode requires PDF version 1.4.");
      tp->mode.fill = TPIC_MODE__FILL_SOLID;
    }
  }

  return  error;
}
#endif  /* DEBUG */


static struct spc_handler tpic_handlers[] = {
  {"pn", spc_handler_tpic_pn},
  {"pa", spc_handler_tpic_pa},
  {"fp", spc_handler_tpic_fp},
  {"ip", spc_handler_tpic_ip},
  {"da", spc_handler_tpic_da},
  {"dt", spc_handler_tpic_dt},
  {"sp", spc_handler_tpic_sp},
  {"ar", spc_handler_tpic_ar},
  {"ia", spc_handler_tpic_ia},
  {"sh", spc_handler_tpic_sh},
  {"wh", spc_handler_tpic_wh},
  {"bk", spc_handler_tpic_bk},
  {"tx", spc_handler_tpic_tx}
};

int
spc_tpic_check_special (const char *buf, int len)
{
  int    istpic = 0;
  char  *q;
  const char *p, *endptr;
  int    i, hasnsp = 0;

  p      = buf;
  endptr = p + len;

  skip_blank(&p, endptr);
#if  ENABLE_SPC_NAMESPACE
  if (p + strlen("tpic:") < endptr &&
      !memcmp(p, "tpic:", strlen("tpic:")))
  {
    p += strlen("tpic:");
    hasnsp = 1;
  }
#endif
  q = parse_c_ident(&p, endptr);

  if (!q)
    istpic = 0;
  else if (q && hasnsp && !strcmp(q, "__setopt__")) {
#if  DEBUG
    istpic = 1;
#endif
    RELEASE(q);
  } else {
    for (i = 0;
         i < sizeof(tpic_handlers)/sizeof(struct spc_handler); i++) {
      if (!strcmp(q, tpic_handlers[i].key)) {
        istpic = 1;
        break;
      }
    }
    RELEASE(q);
  }

  return  istpic;
}


int
spc_tpic_setup_handler (struct spc_handler *sph,
                        struct spc_env *spe, struct spc_arg *ap)
{
  char  *q;
  int    i, hasnsp = 0, error = -1;

  ASSERT(sph && spe && ap);

  skip_blank(&ap->curptr, ap->endptr);
#if  ENABLE_SPC_NAMESPACE
  if (ap->curptr + strlen("tpic:") < ap->endptr &&
      !memcmp(ap->curptr, "tpic:", strlen("tpic:")))
  {
    ap->curptr += strlen("tpic:");
    hasnsp = 1;
  }
#endif
  q = parse_c_ident(&ap->curptr, ap->endptr);

  if (!q)
    error = -1;
  else if (q && hasnsp && !strcmp(q, "__setopt__")) {
#if  DEBUG
    ap->command = "__setopt__";
    sph->key    = "tpic:";
    sph->exec   = spc_handler_tpic__setopts;
    skip_blank(&ap->curptr, ap->endptr);
    error = 0;
#endif
    RELEASE(q);
  } else {
    for (i = 0;
         i < sizeof(tpic_handlers)/sizeof(struct spc_handler); i++) {
      if (!strcmp(q, tpic_handlers[i].key)) {
        ap->command = tpic_handlers[i].key;
        sph->key    = "tpic:";
        sph->exec   = tpic_handlers[i].exec;
        skip_blank(&ap->curptr, ap->endptr);
        error = 0;
        break;
      }
    }
    RELEASE(q);
  }

  return  error;
}


#if  0
int
spc_load_tpic_special  (struct spc_env *spe, pdf_obj *lopts)
{
  struct spc_def   *spd;
  struct spc_tpic_ *sd;

  sd  = NEW(1, struct spc_tpic_);

  spd = NEW(1, struct spc_def);
  spc_init_def(spd);

  spc_def_init   (spd, &spc_handler_tpic__init);
  spc_def_setopts(spd, &spc_handler_tpic__setopts);
  spc_def_bophook(spd, &spc_handler_tpic__bophook);
  spc_def_eophook(spd, &spc_handler_tpic__eophook);
  spc_def_clean  (spd, &spc_handler_tpic__clean);

  spc_def_func(spd, "pn", &spc_handler_tpic_pn);
  spc_def_func(spd, "pa", &spc_handler_tpic_pa);
  spc_def_func(spd, "fp", &spc_handler_tpic_fp);
  spc_def_func(spd, "ip", &spc_handler_tpic_ip);
  spc_def_func(spd, "da", &spc_handler_tpic_da);
  spc_def_func(spd, "dt", &spc_handler_tpic_dt);
  spc_def_func(spd, "sp", &spc_handler_tpic_sp);
  spc_def_func(spd, "ar", &spc_handler_tpic_ar);
  spc_def_func(spd, "ia", &spc_handler_tpic_ia);
  spc_def_func(spd, "sh", &spc_handler_tpic_sh);
  spc_def_func(spd, "wh", &spc_handler_tpic_wh);
  spc_def_func(spd, "bk", &spc_handler_tpic_bk);
  spc_def_func(spd, "tx", &spc_handler_tpic_tx);

  spc_add_special(spe, "tpic", spd, sd);

  return  0;
}
#endif /* 0 */