tmap.c - plan9port - [fork] Plan 9 from user space
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tmap.c (25635B)
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1 #include <u.h>
2 #include <libc.h>
3 #include <stdio.h>
4 #include "map.h"
5 #include "iplot.h"
6
7 #define NVERT 20 /* max number of vertices in a -v polygon */
8 #define HALFWIDTH 8192 /* output scaled to fit in -HALFWIDTH,HALFWIDTH */
9 #define LONGLINES (HALFWIDTH*4) /* permissible segment lengths */
10 #define SHORTLINES (HALFWIDTH/8)
11 #define SCALERATIO 10 /* of abs to rel data (see map(5)) */
12 #define RESOL 2. /* coarsest resolution for tracing grid (degrees) */
13 #define TWO_THRD 0.66666666666666667
14
15 int normproj(double, double, double *, double *);
16 int posproj(double, double, double *, double *);
17 int picut(struct place *, struct place *, double *);
18 double reduce(double);
19 short getshort(FILE *);
20 char *mapindex(char *);
21 proj projection;
22
23
24 static char *mapdir = "#9/map"; /* default map directory */
25 struct file {
26 char *name;
27 char *color;
28 char *style;
29 };
30 static struct file dfltfile = {
31 "world", BLACK, SOLID /* default map */
32 };
33 static struct file *file = &dfltfile; /* list of map files */
34 static int nfile = 1; /* length of list */
35 static char *currcolor = BLACK; /* current color */
36 static char *gridcolor = BLACK;
37 static char *bordcolor = BLACK;
38
39 extern struct index index[];
40 int halfwidth = HALFWIDTH;
41
42 static int (*cut)(struct place *, struct place *, double *);
43 static int (*limb)(double*, double*, double);
44 static void dolimb(void);
45 static int onlimb;
46 static int poles;
47 static double orientation[3] = { 90., 0., 0. }; /* -o option */
48 static int oriented; /* nonzero if -o option occurred */
49 static int upright; /* 1 if orientation[0]==90, -1 if -90, else 0*/
50 static int delta = 1; /* -d setting */
51 static double limits[4] = { /* -l parameters */
52 -90., 90., -180., 180.
53 };
54 static double klimits[4] = { /* -k parameters */
55 -90., 90., -180., 180.
56 };
57 static int limcase;
58 static double rlimits[4]; /* limits expressed in radians */
59 static double lolat, hilat, lolon, hilon;
60 static double window[4] = { /* option -w */
61 -90., 90., -180., 180.
62 };
63 static int windowed; /* nozero if option -w */
64 static struct vert { double x, y; } v[NVERT+2]; /*clipping polygon*/
65 static struct edge { double a, b, c; } e[NVERT]; /* coeffs for linear inequality */
66 static int nvert; /* number of vertices in clipping polygon */
67
68 static double rwindow[4]; /* window, expressed in radians */
69 static double params[2]; /* projection params */
70 /* bounds on output values before scaling; found by coarse survey */
71 static double xmin = 100.;
72 static double xmax = -100.;
73 static double ymin = 100.;
74 static double ymax = -100.;
75 static double xcent, ycent;
76 static double xoff, yoff;
77 double xrange, yrange;
78 static int left = -HALFWIDTH;
79 static int right = HALFWIDTH;
80 static int bottom = -HALFWIDTH;
81 static int top = HALFWIDTH;
82 static int longlines = SHORTLINES; /* drop longer segments */
83 static int shortlines = SHORTLINES;
84 static int bflag = 1; /* 0 for option -b */
85 static int s1flag = 0; /* 1 for option -s1 */
86 static int s2flag = 0; /* 1 for option -s2 */
87 static int rflag = 0; /* 1 for option -r */
88 static int kflag = 0; /* 1 if option -k occurred */
89 static int xflag = 0; /* 1 for option -x */
90 int vflag = 1; /* -1 if option -v occurred */
91 static double position[3]; /* option -p */
92 static double center[3] = {0., 0., 0.}; /* option -c */
93 static struct coord crot; /* option -c */
94 static double grid[3] = { 10., 10., RESOL }; /* option -g */
95 static double dlat, dlon; /* resolution for tracing grid in lat and lon */
96 static double scaling; /* to compute final integer output */
97 static struct file *track; /* options -t and -u */
98 static int ntrack; /* number of tracks present */
99 static char *symbolfile; /* option -y */
100
101 void clamp(double *px, double v);
102 void clipinit(void);
103 double diddle(struct place *, double, double);
104 double diddle(struct place *, double, double);
105 void dobounds(double, double, double, double, int);
106 void dogrid(double, double, double, double);
107 int duple(struct place *, double);
108 #define fmax map_fmax
109 #define fmin map_fmin
110 double fmax(double, double);
111 double fmin(double, double);
112 void getdata(char *);
113 int gridpt(double, double, int);
114 int inpoly(double, double);
115 int inwindow(struct place *);
116 void pathnames(void);
117 int pnorm(double);
118 void radbds(double *w, double *rw);
119 void revlon(struct place *, double);
120 void satellite(struct file *);
121 int seeable(double, double);
122 void windlim(void);
123 void realcut(void);
124
125 int
126 option(char *s)
127 {
128
129 if(s[0]=='-' && (s[1]<'0'||s[1]>'9'))
130 return(s[1]!='.'&&s[1]!=0);
131 else
132 return(0);
133 }
134
135 void
136 conv(int k, struct coord *g)
137 {
138 g->l = (0.0001/SCALERATIO)*k;
139 sincos(g);
140 }
141
142 int
143 main(int argc, char *argv[])
144 {
145 int i,k;
146 char *s, *t, *style;
147 double x, y;
148 double lat, lon;
149 double *wlim;
150 double dd;
151 if(sizeof(short)!=2)
152 abort(); /* getshort() won't work */
153 mapdir = unsharp(mapdir);
154 s = getenv("MAP");
155 if(s)
156 file[0].name = s;
157 s = getenv("MAPDIR");
158 if(s)
159 mapdir = s;
160 if(argc<=1)
161 error("usage: map projection params options");
162 for(k=0;index[k].name;k++) {
163 s = index[k].name;
164 t = argv[1];
165 while(*s == *t){
166 if(*s==0) goto found;
167 s++;
168 t++;
169 }
170 }
171 fprintf(stderr,"projections:\n");
172 for(i=0;index[i].name;i++) {
173 fprintf(stderr,"%s",index[i].name);
174 for(k=0; k<index[i].npar; k++)
175 fprintf(stderr," p%d", k);
176 fprintf(stderr,"\n");
177 }
178 exits("error");
179 found:
180 argv += 2;
181 argc -= 2;
182 cut = index[k].cut;
183 limb = index[k].limb;
184 poles = index[k].poles;
185 for(i=0;i<index[k].npar;i++) {
186 if(i>=argc||option(argv[i])) {
187 fprintf(stderr,"%s needs %d params\n",index[k].name,index[k].npar);
188 exits("error");
189 }
190 params[i] = atof(argv[i]);
191 }
192 argv += i;
193 argc -= i;
194 while(argc>0&&option(argv[0])) {
195 argc--;
196 argv++;
197 switch(argv[-1][1]) {
198 case 'm':
199 if(file == &dfltfile) {
200 file = 0;
201 nfile = 0;
202 }
203 while(argc && !option(*argv)) {
204 file = realloc(file,(nfile+1)*sizeof(*file));
205 file[nfile].name = *argv;
206 file[nfile].color = currcolor;
207 file[nfile].style = SOLID;
208 nfile++;
209 argv++;
210 argc--;
211 }
212 break;
213 case 'b':
214 bflag = 0;
215 for(nvert=0;nvert<NVERT&&argc>=2;nvert++) {
216 if(option(*argv))
217 break;
218 v[nvert].x = atof(*argv++);
219 argc--;
220 if(option(*argv))
221 break;
222 v[nvert].y = atof(*argv++);
223 argc--;
224 }
225 if(nvert>=NVERT)
226 error("too many clipping vertices");
227 break;
228 case 'g':
229 gridcolor = currcolor;
230 for(i=0;i<3&&argc>i&&!option(argv[i]);i++)
231 grid[i] = atof(argv[i]);
232 switch(i) {
233 case 0:
234 grid[0] = grid[1] = 0.;
235 break;
236 case 1:
237 grid[1] = grid[0];
238 }
239 argc -= i;
240 argv += i;
241 break;
242 case 't':
243 style = SOLID;
244 goto casetu;
245 case 'u':
246 style = DOTDASH;
247 casetu:
248 while(argc && !option(*argv)) {
249 track = realloc(track,(ntrack+1)*sizeof(*track));
250 track[ntrack].name = *argv;
251 track[ntrack].color = currcolor;
252 track[ntrack].style = style;
253 ntrack++;
254 argv++;
255 argc--;
256 }
257 break;
258 case 'r':
259 rflag++;
260 break;
261 case 's':
262 switch(argv[-1][2]) {
263 case '1':
264 s1flag++;
265 break;
266 case 0: /* compatibility */
267 case '2':
268 s2flag++;
269 }
270 break;
271 case 'o':
272 for(i=0;i<3&&i<argc&&!option(argv[i]);i++)
273 orientation[i] = atof(argv[i]);
274 oriented++;
275 argv += i;
276 argc -= i;
277 break;
278 case 'l':
279 bordcolor = currcolor;
280 for(i=0;i<argc&&i<4&&!option(argv[i]);i++)
281 limits[i] = atof(argv[i]);
282 argv += i;
283 argc -= i;
284 break;
285 case 'k':
286 kflag++;
287 for(i=0;i<argc&&i<4&&!option(argv[i]);i++)
288 klimits[i] = atof(argv[i]);
289 argv += i;
290 argc -= i;
291 break;
292 case 'd':
293 if(argc>0&&!option(argv[0])) {
294 delta = atoi(argv[0]);
295 argv++;
296 argc--;
297 }
298 break;
299 case 'w':
300 bordcolor = currcolor;
301 windowed++;
302 for(i=0;i<argc&&i<4&&!option(argv[i]);i++)
303 window[i] = atof(argv[i]);
304 argv += i;
305 argc -= i;
306 break;
307 case 'c':
308 for(i=0;i<3&&argc>i&&!option(argv[i]);i++)
309 center[i] = atof(argv[i]);
310 argc -= i;
311 argv += i;
312 break;
313 case 'p':
314 for(i=0;i<3&&argc>i&&!option(argv[i]);i++)
315 position[i] = atof(argv[i]);
316 argc -= i;
317 argv += i;
318 if(i!=3||position[2]<=0)
319 error("incomplete positioning");
320 break;
321 case 'y':
322 if(argc>0&&!option(argv[0])) {
323 symbolfile = argv[0];
324 argc--;
325 argv++;
326 }
327 break;
328 case 'v':
329 if(index[k].limb == 0)
330 error("-v does not apply here");
331 vflag = -1;
332 break;
333 case 'x':
334 xflag = 1;
335 break;
336 case 'C':
337 if(argc && !option(*argv)) {
338 currcolor = colorcode(*argv);
339 argc--;
340 argv++;
341 }
342 break;
343 }
344 }
345 if(argc>0)
346 error("error in arguments");
347 pathnames();
348 clamp(&limits[0],-90.);
349 clamp(&limits[1],90.);
350 clamp(&klimits[0],-90.);
351 clamp(&klimits[1],90.);
352 clamp(&window[0],-90.);
353 clamp(&window[1],90.);
354 radbds(limits,rlimits);
355 limcase = limits[2]<-180.?0:
356 limits[3]>180.?2:
357 1;
358 if(
359 window[0]>=window[1]||
360 window[2]>=window[3]||
361 window[0]>90.||
362 window[1]<-90.||
363 window[2]>180.||
364 window[3]<-180.)
365 error("unreasonable window");
366 windlim();
367 radbds(window,rwindow);
368 upright = orientation[0]==90? 1: orientation[0]==-90? -1: 0;
369 if(index[k].spheroid && !upright)
370 error("can't tilt the spheroid");
371 if(limits[2]>limits[3])
372 limits[3] += 360;
373 if(!oriented)
374 orientation[2] = (limits[2]+limits[3])/2;
375 orient(orientation[0],orientation[1],orientation[2]);
376 projection = (*index[k].prog)(params[0],params[1]);
377 if(projection == 0)
378 error("unreasonable projection parameters");
379 clipinit();
380 grid[0] = fabs(grid[0]);
381 grid[1] = fabs(grid[1]);
382 if(!kflag)
383 for(i=0;i<4;i++)
384 klimits[i] = limits[i];
385 if(klimits[2]>klimits[3])
386 klimits[3] += 360;
387 lolat = limits[0];
388 hilat = limits[1];
389 lolon = limits[2];
390 hilon = limits[3];
391 if(lolon>=hilon||lolat>=hilat||lolat<-90.||hilat>90.)
392 error("unreasonable limits");
393 wlim = kflag? klimits: window;
394 dlat = fmin(hilat-lolat,wlim[1]-wlim[0])/16;
395 dlon = fmin(hilon-lolon,wlim[3]-wlim[2])/32;
396 dd = fmax(dlat,dlon);
397 while(grid[2]>fmin(dlat,dlon)/2)
398 grid[2] /= 2;
399 realcut();
400 if(nvert<=0) {
401 for(lat=klimits[0];lat<klimits[1]+dd-FUZZ;lat+=dd) {
402 if(lat>klimits[1])
403 lat = klimits[1];
404 for(lon=klimits[2];lon<klimits[3]+dd-FUZZ;lon+=dd) {
405 i = (kflag?posproj:normproj)
406 (lat,lon+(lon<klimits[3]?FUZZ:-FUZZ),
407 &x,&y);
408 if(i*vflag <= 0)
409 continue;
410 if(x<xmin) xmin = x;
411 if(x>xmax) xmax = x;
412 if(y<ymin) ymin = y;
413 if(y>ymax) ymax = y;
414 }
415 }
416 } else {
417 for(i=0; i<nvert; i++) {
418 x = v[i].x;
419 y = v[i].y;
420 if(x<xmin) xmin = x;
421 if(x>xmax) xmax = x;
422 if(y<ymin) ymin = y;
423 if(y>ymax) ymax = y;
424 }
425 }
426 xrange = xmax - xmin;
427 yrange = ymax - ymin;
428 if(xrange<=0||yrange<=0)
429 error("map seems to be empty");
430 scaling = 2; /*plotting area from -1 to 1*/
431 if(position[2]!=0) {
432 if(posproj(position[0]-.5,position[1],&xcent,&ycent)==0||
433 posproj(position[0]+.5,position[1],&x,&y)==0)
434 error("unreasonable position");
435 scaling /= (position[2]*hypot(x-xcent,y-ycent));
436 if(posproj(position[0],position[1],&xcent,&ycent)==0)
437 error("unreasonable position");
438 } else {
439 scaling /= (xrange>yrange?xrange:yrange);
440 xcent = (xmin+xmax)/2;
441 ycent = (ymin+ymax)/2;
442 }
443 xoff = center[0]/scaling;
444 yoff = center[1]/scaling;
445 crot.l = center[2]*RAD;
446 sincos(&crot);
447 scaling *= HALFWIDTH*0.9;
448 if(symbolfile)
449 getsyms(symbolfile);
450 if(!s2flag) {
451 openpl();
452 erase();
453 }
454 range(left,bottom,right,top);
455 comment("grid","");
456 colorx(gridcolor);
457 pen(DOTTED);
458 if(grid[0]>0.)
459 for(lat=ceil(lolat/grid[0])*grid[0];
460 lat<=hilat;lat+=grid[0])
461 dogrid(lat,lat,lolon,hilon);
462 if(grid[1]>0.)
463 for(lon=ceil(lolon/grid[1])*grid[1];
464 lon<=hilon;lon+=grid[1])
465 dogrid(lolat,hilat,lon,lon);
466 comment("border","");
467 colorx(bordcolor);
468 pen(SOLID);
469 if(bflag) {
470 dolimb();
471 dobounds(lolat,hilat,lolon,hilon,0);
472 dobounds(window[0],window[1],window[2],window[3],1);
473 }
474 lolat = floor(limits[0]/10)*10;
475 hilat = ceil(limits[1]/10)*10;
476 lolon = floor(limits[2]/10)*10;
477 hilon = ceil(limits[3]/10)*10;
478 if(lolon>hilon)
479 hilon += 360.;
480 /*do tracks first so as not to lose the standard input*/
481 for(i=0;i<ntrack;i++) {
482 longlines = LONGLINES;
483 satellite(&track[i]);
484 longlines = shortlines;
485 }
486 for(i=0;i<nfile;i++) {
487 comment("mapfile",file[i].name);
488 colorx(file[i].color);
489 pen(file[i].style);
490 getdata(file[i].name);
491 }
492 move(right,bottom);
493 if(!s1flag)
494 closepl();
495 return 0;
496 }
497
498 /* Out of perverseness (really to recover from a dubious,
499 but documented, convention) the returns from projection
500 functions (-1 unplottable, 0 wrong sheet, 1 good) are
501 recoded into -1 wrong sheet, 0 unplottable, 1 good. */
502
503 int
504 fixproj(struct place *g, double *x, double *y)
505 {
506 int i = (*projection)(g,x,y);
507 return i<0? 0: i==0? -1: 1;
508 }
509
510 int
511 normproj(double lat, double lon, double *x, double *y)
512 {
513 int i;
514 struct place geog;
515 latlon(lat,lon,&geog);
516 /*
517 printp(&geog);
518 */
519 normalize(&geog);
520 if(!inwindow(&geog))
521 return(-1);
522 i = fixproj(&geog,x,y);
523 if(rflag)
524 *x = -*x;
525 /*
526 printp(&geog);
527 fprintf(stderr,"%d %.3f %.3f\n",i,*x,*y);
528 */
529 return(i);
530 }
531
532 int
533 posproj(double lat, double lon, double *x, double *y)
534 {
535 int i;
536 struct place geog;
537 latlon(lat,lon,&geog);
538 normalize(&geog);
539 i = fixproj(&geog,x,y);
540 if(rflag)
541 *x = -*x;
542 return(i);
543 }
544
545 int
546 inwindow(struct place *geog)
547 {
548 if(geog->nlat.l<rwindow[0]-FUZZ||
549 geog->nlat.l>rwindow[1]+FUZZ||
550 geog->wlon.l<rwindow[2]-FUZZ||
551 geog->wlon.l>rwindow[3]+FUZZ)
552 return(0);
553 else return(1);
554 }
555
556 int
557 inlimits(struct place *g)
558 {
559 if(rlimits[0]-FUZZ>g->nlat.l||
560 rlimits[1]+FUZZ<g->nlat.l)
561 return(0);
562 switch(limcase) {
563 case 0:
564 if(rlimits[2]+TWOPI-FUZZ>g->wlon.l&&
565 rlimits[3]+FUZZ<g->wlon.l)
566 return(0);
567 break;
568 case 1:
569 if(rlimits[2]-FUZZ>g->wlon.l||
570 rlimits[3]+FUZZ<g->wlon.l)
571 return(0);
572 break;
573 case 2:
574 if(rlimits[2]>g->wlon.l&&
575 rlimits[3]-TWOPI+FUZZ<g->wlon.l)
576 return(0);
577 break;
578 }
579 return(1);
580 }
581
582
583 long patch[18][36];
584
585 void
586 getdata(char *mapfile)
587 {
588 char *indexfile;
589 int kx,ky,c;
590 int k;
591 long b;
592 long *p;
593 int ip, jp;
594 int n;
595 struct place g;
596 int i, j;
597 double lat, lon;
598 int conn;
599 FILE *ifile, *xfile;
600
601 indexfile = mapindex(mapfile);
602 xfile = fopen(indexfile,"r");
603 if(xfile==NULL)
604 filerror("can't find map index", indexfile);
605 free(indexfile);
606 for(i=0,p=patch[0];i<18*36;i++,p++)
607 *p = 1;
608 while(!feof(xfile) && fscanf(xfile,"%d%d%ld",&i,&j,&b)==3)
609 patch[i+9][j+18] = b;
610 fclose(xfile);
611 ifile = fopen(mapfile,"r");
612 if(ifile==NULL)
613 filerror("can't find map data", mapfile);
614 for(lat=lolat;lat<hilat;lat+=10.)
615 for(lon=lolon;lon<hilon;lon+=10.) {
616 if(!seeable(lat,lon))
617 continue;
618 i = pnorm(lat);
619 j = pnorm(lon);
620 if((b=patch[i+9][j+18])&1)
621 continue;
622 fseek(ifile,b,0);
623 while((ip=getc(ifile))>=0&&(jp=getc(ifile))>=0){
624 if(ip!=(i&0377)||jp!=(j&0377))
625 break;
626 n = getshort(ifile);
627 conn = 0;
628 if(n > 0) { /* absolute coordinates */
629 kx = ky = 0; /* set */
630 for(k=0;k<n;k++){
631 kx = SCALERATIO*getshort(ifile);
632 ky = SCALERATIO*getshort(ifile);
633 if (((k%delta) != 0) && (k != (n-1)))
634 continue;
635 conv(kx,&g.nlat);
636 conv(ky,&g.wlon);
637 conn = plotpt(&g,conn);
638 }
639 } else { /* differential, scaled by SCALERATI0 */
640 n = -n;
641 kx = SCALERATIO*getshort(ifile);
642 ky = SCALERATIO*getshort(ifile);
643 for(k=0; k<n; k++) {
644 c = getc(ifile);
645 if(c&0200) c|= ~0177;
646 kx += c;
647 c = getc(ifile);
648 if(c&0200) c|= ~0177;
649 ky += c;
650 if(k%delta!=0&&k!=n-1)
651 continue;
652 conv(kx,&g.nlat);
653 conv(ky,&g.wlon);
654 conn = plotpt(&g,conn);
655 }
656 }
657 if(k==1) {
658 conv(kx,&g.nlat);
659 conv(ky,&g.wlon);
660 plotpt(&g,conn);
661 }
662 }
663 }
664 fclose(ifile);
665 }
666
667 int
668 seeable(double lat0, double lon0)
669 {
670 double x, y;
671 double lat, lon;
672 for(lat=lat0;lat<=lat0+10;lat+=2*grid[2])
673 for(lon=lon0;lon<=lon0+10;lon+=2*grid[2])
674 if(normproj(lat,lon,&x,&y)*vflag>0)
675 return(1);
676 return(0);
677 }
678
679 void
680 satellite(struct file *t)
681 {
682 char sym[50];
683 char lbl[50];
684 double scale;
685 int conn;
686 double lat,lon;
687 struct place place;
688 static FILE *ifile;
689
690 if(ifile == nil)
691 ifile = stdin;
692 if(t->name[0]!='-'||t->name[1]!=0) {
693 fclose(ifile);
694 if((ifile=fopen(t->name,"r"))==NULL)
695 filerror("can't find track", t->name);
696 }
697 comment("track",t->name);
698 colorx(t->color);
699 pen(t->style);
700 for(;;) {
701 conn = 0;
702 while(!feof(ifile) && fscanf(ifile,"%lf%lf",&lat,&lon)==2){
703 latlon(lat,lon,&place);
704 if(fscanf(ifile,"%1s",lbl) == 1) {
705 if(strchr("+-.0123456789",*lbl)==0)
706 break;
707 ungetc(*lbl,ifile);
708 }
709 conn = plotpt(&place,conn);
710 }
711 if(feof(ifile))
712 return;
713 fscanf(ifile,"%[^\n]",lbl+1);
714 switch(*lbl) {
715 case '"':
716 if(plotpt(&place,conn))
717 text(lbl+1);
718 break;
719 case ':':
720 case '!':
721 if(sscanf(lbl+1,"%s %lf",sym,&scale) <= 1)
722 scale = 1;
723 if(plotpt(&place,conn?conn:-1)) {
724 int r = *lbl=='!'?0:rflag?-1:1;
725 pen(SOLID);
726 if(putsym(&place,sym,scale,r) == 0)
727 text(lbl);
728 pen(t->style);
729 }
730 break;
731 default:
732 if(plotpt(&place,conn))
733 text(lbl);
734 break;
735 }
736 }
737 }
738
739 int
740 pnorm(double x)
741 {
742 int i;
743 i = x/10.;
744 i %= 36;
745 if(i>=18) return(i-36);
746 if(i<-18) return(i+36);
747 return(i);
748 }
749
750 void
751 error(char *s)
752 {
753 fprintf(stderr,"map: \r\n%s\n",s);
754 exits("error");
755 }
756
757 void
758 filerror(char *s, char *f)
759 {
760 fprintf(stderr,"\r\n%s %s\n",s,f);
761 exits("error");
762 }
763
764 char *
765 mapindex(char *s)
766 {
767 char *t = malloc(strlen(s)+3);
768 strcpy(t,s);
769 strcat(t,".x");
770 return t;
771 }
772
773 #define NOPT 32767
774 static int ox = NOPT;
775 static int oy = NOPT;
776
777 int
778 cpoint(int xi, int yi, int conn)
779 {
780 int dx = abs(ox-xi);
781 int dy = abs(oy-yi);
782 if(!xflag && (xi<left||xi>=right || yi<bottom||yi>=top)) {
783 ox = oy = NOPT;
784 return 0;
785 }
786 if(conn == -1) /* isolated plotting symbol */
787 {}
788 else if(!conn)
789 point(xi,yi);
790 else {
791 if(dx+dy>longlines) {
792 ox = oy = NOPT; /* don't leap across cuts */
793 return 0;
794 }
795 if(dx || dy)
796 vec(xi,yi);
797 }
798 ox = xi, oy = yi;
799 return dx+dy<=2? 2: 1; /* 2=very near; see dogrid */
800 }
801
802
803 struct place oldg;
804
805 int
806 plotpt(struct place *g, int conn)
807 {
808 int kx,ky;
809 int ret;
810 double cutlon;
811 if(!inlimits(g)) {
812 return(0);
813 }
814 normalize(g);
815 if(!inwindow(g)) {
816 return(0);
817 }
818 switch((*cut)(g,&oldg,&cutlon)) {
819 case 2:
820 if(conn) {
821 ret = duple(g,cutlon)|duple(g,cutlon);
822 oldg = *g;
823 return(ret);
824 }
825 case 0:
826 conn = 0;
827 default: /* prevent diags about bad return value */
828 case 1:
829 oldg = *g;
830 ret = doproj(g,&kx,&ky);
831 if(ret==0 || !onlimb && ret*vflag<=0)
832 return(0);
833 ret = cpoint(kx,ky,conn);
834 return ret;
835 }
836 }
837
838 int
839 doproj(struct place *g, int *kx, int *ky)
840 {
841 int i;
842 double x,y,x1,y1;
843 /*fprintf(stderr,"dopr1 %f %f \n",g->nlat.l,g->wlon.l);*/
844 i = fixproj(g,&x,&y);
845 if(i == 0)
846 return(0);
847 if(rflag)
848 x = -x;
849 /*fprintf(stderr,"dopr2 %f %f\n",x,y);*/
850 if(!inpoly(x,y)) {
851 return 0;
852 }
853 x1 = x - xcent;
854 y1 = y - ycent;
855 x = (x1*crot.c - y1*crot.s + xoff)*scaling;
856 y = (x1*crot.s + y1*crot.c + yoff)*scaling;
857 *kx = x + (x>0?.5:-.5);
858 *ky = y + (y>0?.5:-.5);
859 return(i);
860 }
861
862 int
863 duple(struct place *g, double cutlon)
864 {
865 int kx,ky;
866 int okx,oky;
867 struct place ig;
868 revlon(g,cutlon);
869 revlon(&oldg,cutlon);
870 ig = *g;
871 invert(&ig);
872 if(!inlimits(&ig))
873 return(0);
874 if(doproj(g,&kx,&ky)*vflag<=0 ||
875 doproj(&oldg,&okx,&oky)*vflag<=0)
876 return(0);
877 cpoint(okx,oky,0);
878 cpoint(kx,ky,1);
879 return(1);
880 }
881
882 void
883 revlon(struct place *g, double cutlon)
884 {
885 g->wlon.l = reduce(cutlon-reduce(g->wlon.l-cutlon));
886 sincos(&g->wlon);
887 }
888
889
890 /* recognize problems of cuts
891 * move a point across cut to side of its predecessor
892 * if its very close to the cut
893 * return(0) if cut interrupts the line
894 * return(1) if line is to be drawn normally
895 * return(2) if line is so close to cut as to
896 * be properly drawn on both sheets
897 */
898
899 int
900 picut(struct place *g, struct place *og, double *cutlon)
901 {
902 *cutlon = PI;
903 return(ckcut(g,og,PI));
904 }
905
906 int
907 nocut(struct place *g, struct place *og, double *cutlon)
908 {
909 USED(g);
910 USED(og);
911 USED(cutlon);
912 /*
913 #pragma ref g
914 #pragma ref og
915 #pragma ref cutlon
916 */
917 return(1);
918 }
919
920 int
921 ckcut(struct place *g1, struct place *g2, double lon)
922 {
923 double d1, d2;
924 double f1, f2;
925 int kx,ky;
926 d1 = reduce(g1->wlon.l -lon);
927 d2 = reduce(g2->wlon.l -lon);
928 if((f1=fabs(d1))<FUZZ)
929 d1 = diddle(g1,lon,d2);
930 if((f2=fabs(d2))<FUZZ) {
931 d2 = diddle(g2,lon,d1);
932 if(doproj(g2,&kx,&ky)*vflag>0)
933 cpoint(kx,ky,0);
934 }
935 if(f1<FUZZ&&f2<FUZZ)
936 return(2);
937 if(f1>PI*TWO_THRD||f2>PI*TWO_THRD)
938 return(1);
939 return(d1*d2>=0);
940 }
941
942 double
943 diddle(struct place *g, double lon, double d)
944 {
945 double d1;
946 d1 = FUZZ/2;
947 if(d<0)
948 d1 = -d1;
949 g->wlon.l = reduce(lon+d1);
950 sincos(&g->wlon);
951 return(d1);
952 }
953
954 double
955 reduce(double lon)
956 {
957 if(lon>PI)
958 lon -= 2*PI;
959 else if(lon<-PI)
960 lon += 2*PI;
961 return(lon);
962 }
963
964
965 double tetrapt = 35.26438968; /* atan(1/sqrt(2)) */
966
967 void
968 dogrid(double lat0, double lat1, double lon0, double lon1)
969 {
970 double slat,slon,tlat,tlon;
971 register int conn, oconn;
972 slat = tlat = slon = tlon = 0;
973 if(lat1>lat0)
974 slat = tlat = fmin(grid[2],dlat);
975 else
976 slon = tlon = fmin(grid[2],dlon);;
977 conn = oconn = 0;
978 while(lat0<=lat1&&lon0<=lon1) {
979 conn = gridpt(lat0,lon0,conn);
980 if(projection==Xguyou&&slat>0) {
981 if(lat0<-45&&lat0+slat>-45)
982 conn = gridpt(-45.,lon0,conn);
983 else if(lat0<45&&lat0+slat>45)
984 conn = gridpt(45.,lon0,conn);
985 } else if(projection==Xtetra&&slat>0) {
986 if(lat0<-tetrapt&&lat0+slat>-tetrapt) {
987 gridpt(-tetrapt-.001,lon0,conn);
988 conn = gridpt(-tetrapt+.001,lon0,0);
989 }
990 else if(lat0<tetrapt&&lat0+slat>tetrapt) {
991 gridpt(tetrapt-.001,lon0,conn);
992 conn = gridpt(tetrapt+.001,lon0,0);
993 }
994 }
995 if(conn==0 && oconn!=0) {
996 if(slat+slon>.05) {
997 lat0 -= slat; /* steps too big */
998 lon0 -= slon; /* or near bdry */
999 slat /= 2;
1000 slon /= 2;
1001 conn = oconn = gridpt(lat0,lon0,conn);
1002 } else
1003 oconn = 0;
1004 } else {
1005 if(conn==2) {
1006 slat = tlat;
1007 slon = tlon;
1008 conn = 1;
1009 }
1010 oconn = conn;
1011 }
1012 lat0 += slat;
1013 lon0 += slon;
1014 }
1015 gridpt(lat1,lon1,conn);
1016 }
1017
1018 static int gridinv; /* nonzero when doing window bounds */
1019
1020 int
1021 gridpt(double lat, double lon, int conn)
1022 {
1023 struct place g;
1024 /*fprintf(stderr,"%f %f\n",lat,lon);*/
1025 latlon(lat,lon,&g);
1026 if(gridinv)
1027 invert(&g);
1028 return(plotpt(&g,conn));
1029 }
1030
1031 /* win=0 ordinary grid lines, win=1 window lines */
1032
1033 void
1034 dobounds(double lolat, double hilat, double lolon, double hilon, int win)
1035 {
1036 gridinv = win;
1037 if(lolat>-90 || win && (poles&1)!=0)
1038 dogrid(lolat+FUZZ,lolat+FUZZ,lolon,hilon);
1039 if(hilat<90 || win && (poles&2)!=0)
1040 dogrid(hilat-FUZZ,hilat-FUZZ,lolon,hilon);
1041 if(hilon-lolon<360 || win && cut==picut) {
1042 dogrid(lolat,hilat,lolon+FUZZ,lolon+FUZZ);
1043 dogrid(lolat,hilat,hilon-FUZZ,hilon-FUZZ);
1044 }
1045 gridinv = 0;
1046 }
1047
1048 static void
1049 dolimb(void)
1050 {
1051 double lat, lon;
1052 double res = fmin(dlat, dlon)/4;
1053 int conn = 0;
1054 int newconn;
1055 if(limb == 0)
1056 return;
1057 onlimb = gridinv = 1;
1058 for(;;) {
1059 newconn = (*limb)(&lat, &lon, res);
1060 if(newconn == -1)
1061 break;
1062 conn = gridpt(lat, lon, conn*newconn);
1063 }
1064 onlimb = gridinv = 0;
1065 }
1066
1067
1068 void
1069 radbds(double *w, double *rw)
1070 {
1071 int i;
1072 for(i=0;i<4;i++)
1073 rw[i] = w[i]*RAD;
1074 rw[0] -= FUZZ;
1075 rw[1] += FUZZ;
1076 rw[2] -= FUZZ;
1077 rw[3] += FUZZ;
1078 }
1079
1080 void
1081 windlim(void)
1082 {
1083 double center = orientation[0];
1084 double colat;
1085 if(center>90)
1086 center = 180 - center;
1087 if(center<-90)
1088 center = -180 - center;
1089 if(fabs(center)>90)
1090 error("unreasonable orientation");
1091 colat = 90 - window[0];
1092 if(center-colat>limits[0])
1093 limits[0] = center - colat;
1094 if(center+colat<limits[1])
1095 limits[1] = center + colat;
1096 }
1097
1098
1099 short
1100 getshort(FILE *f)
1101 {
1102 int c, r;
1103 c = getc(f);
1104 r = (c | getc(f)<<8);
1105 if (r&0x8000)
1106 r |= ~0xFFFF; /* in case short > 16 bits */
1107 return r;
1108 }
1109
1110 double
1111 fmin(double x, double y)
1112 {
1113 return(x<y?x:y);
1114 }
1115
1116 double
1117 fmax(double x, double y)
1118 {
1119 return(x>y?x:y);
1120 }
1121
1122 void
1123 clamp(double *px, double v)
1124 {
1125 *px = (v<0?fmax:fmin)(*px,v);
1126 }
1127
1128 void
1129 pathnames(void)
1130 {
1131 int i;
1132 char *t, *indexfile, *name;
1133 FILE *f, *fx;
1134 for(i=0; i<nfile; i++) {
1135 name = file[i].name;
1136 if(*name=='/')
1137 continue;
1138 indexfile = mapindex(name);
1139 /* ansi equiv of unix access() call */
1140 f = fopen(name, "r");
1141 fx = fopen(indexfile, "r");
1142 if(f) fclose(f);
1143 if(fx) fclose(fx);
1144 free(indexfile);
1145 if(f && fx)
1146 continue;
1147 t = malloc(strlen(name)+strlen(mapdir)+2);
1148 strcpy(t,mapdir);
1149 strcat(t,"/");
1150 strcat(t,name);
1151 file[i].name = t;
1152 }
1153 }
1154
1155 void
1156 clipinit(void)
1157 {
1158 int i;
1159 double s,t;
1160 if(nvert<=0)
1161 return;
1162 for(i=0; i<nvert; i++) { /*convert latlon to xy*/
1163 if(normproj(v[i].x,v[i].y,&v[i].x,&v[i].y)==0)
1164 error("invisible clipping vertex");
1165 }
1166 if(nvert==2) { /*rectangle with diag specified*/
1167 nvert = 4;
1168 v[2] = v[1];
1169 v[1].x=v[0].x, v[1].y=v[2].y, v[3].x=v[2].x, v[3].y=v[0].y;
1170 }
1171 v[nvert] = v[0];
1172 v[nvert+1] = v[1];
1173 s = 0;
1174 for(i=1; i<=nvert; i++) { /*test for convexity*/
1175 t = (v[i-1].x-v[i].x)*(v[i+1].y-v[i].y) -
1176 (v[i-1].y-v[i].y)*(v[i+1].x-v[i].x);
1177 if(t<-FUZZ && s>=0) s = 1;
1178 if(t>FUZZ && s<=0) s = -1;
1179 if(-FUZZ<=t&&t<=FUZZ || t*s>0) {
1180 s = 0;
1181 break;
1182 }
1183 }
1184 if(s==0)
1185 error("improper clipping polygon");
1186 for(i=0; i<nvert; i++) { /*edge equation ax+by=c*/
1187 e[i].a = s*(v[i+1].y - v[i].y);
1188 e[i].b = s*(v[i].x - v[i+1].x);
1189 e[i].c = s*(v[i].x*v[i+1].y - v[i].y*v[i+1].x);
1190 }
1191 }
1192
1193 int
1194 inpoly(double x, double y)
1195 {
1196 int i;
1197 for(i=0; i<nvert; i++) {
1198 register struct edge *ei = &e[i];
1199 double val = x*ei->a + y*ei->b - ei->c;
1200 if(val>10*FUZZ)
1201 return(0);
1202 }
1203 return 1;
1204 }
1205
1206 void
1207 realcut(void)
1208 {
1209 struct place g;
1210 double lat;
1211
1212 if(cut != picut) /* punt on unusual cuts */
1213 return;
1214 for(lat=window[0]; lat<=window[1]; lat+=grid[2]) {
1215 g.wlon.l = PI;
1216 sincos(&g.wlon);
1217 g.nlat.l = lat*RAD;
1218 sincos(&g.nlat);
1219 if(!inwindow(&g)) {
1220 break;
1221 }
1222 invert(&g);
1223 if(inlimits(&g)) {
1224 return;
1225 }
1226 }
1227 longlines = shortlines = LONGLINES;
1228 cut = nocut; /* not necessary; small eff. gain */
1229 }