Pikchr

	echo >> piktcl/pkgIndex.tcl \
	      "package ifneeded $(TCL_PACKAGE_NAME) $(TCL_PACKAGE_VERSION) [list load [file join" '$$dir' "libpikchr.so]]"

lemon:	lemon.c
	$(CC) $(CFLAGS) lemon.c -o lemon

test:	pikchr
	./pikchr tests/*.pikchr >out.html || true
	open out.html || true
	./pikchr --dark-mode */*.pikchr >darkmode.html || true
	open darkmode.html

clean:	
	rm -f pikchr pikchr.c pikchr.h pikchr.out lemon out.html

  unsigned mProp;          /* Masks of properties set so far */
  unsigned mCalc;          /* Values computed from other constraints */
  PToken aTxt[5];          /* Text with .eCode holding TP flags */
  int iLayer;              /* Rendering order */
  int inDir, outDir;       /* Entry and exit directions */
  int nPath;               /* Number of path points */
  PPoint *aPath;           /* Array of path points */
  PObj *pFrom, *pTo;       /* End-point objects of a path */
  PBox bbox;               /* Bounding box */
};

/* A list of graphics objects */
struct PList {
  int n;          /* Number of statements in the list */
  int nAlloc;     /* Allocated slots in a[] */

  PToken sIn;              /* Input Pikchr-language text */
  char *zOut;              /* Result accumulates here */
  unsigned int nOut;       /* Bytes written to zOut[] so far */
  unsigned int nOutAlloc;  /* Space allocated to zOut[] */
  unsigned char eDir;      /* Current direction */
  unsigned int mFlags;     /* Flags passed to pikchr() */
  PObj *cur;               /* Object under construction */
  PObj *lastRef;           /* Last object references by "place" */
  PList *list;             /* Object list under construction */
  PMacro *pMacros;         /* List of all defined macros */
  PVar *pVar;              /* Application-defined variables */
  PBox bbox;               /* Bounding box around all statements */
                           /* Cache of layout values.  <=0.0 for unknown... */
  PNum rScale;                 /* Multiply to convert inches to pixels */
  PNum fontScale;              /* Scale fonts by this percent */

static void pik_behind(Pik*,PObj*);
static PObj *pik_assert(Pik*,PNum,PToken*,PNum);
static PObj *pik_position_assert(Pik*,PPoint*,PToken*,PPoint*);
static PNum pik_dist(PPoint*,PPoint*);
static void pik_add_macro(Pik*,PToken *pId,PToken *pCode);


#line 510 "pikchr.c"
/**************** End of %include directives **********************************/
/* These constants specify the various numeric values for terminal symbols.
***************** Begin token definitions *************************************/
#ifndef T_ID
#define T_ID                              1
#define T_EDGEPT                          2
#define T_OF                              3

    ** Note: during a reduce, the only symbols destroyed are those
    ** which appear on the RHS of the rule, but which are *not* used
    ** inside the C code.
    */
/********* Begin destructor definitions ***************************************/
    case 99: /* statement_list */
{
#line 499 "pikchr.y"
pik_elist_free(p,(yypminor->yy227));
#line 1740 "pikchr.c"
}
      break;
    case 100: /* statement */
    case 101: /* unnamed_statement */
    case 102: /* basetype */
{
#line 501 "pikchr.y"
pik_elem_free(p,(yypminor->yy36));
#line 1749 "pikchr.c"
}
      break;
/********* End destructor definitions *****************************************/
    default:  break;   /* If no destructor action specified: do nothing */
  }
}

     fprintf(yyTraceFILE,"%sStack Overflow!\n",yyTracePrompt);
   }
#endif
   while( yypParser->yytos>yypParser->yystack ) yy_pop_parser_stack(yypParser);
   /* Here code is inserted which will execute if the parser
   ** stack every overflows */
/******** Begin %stack_overflow code ******************************************/
#line 533 "pikchr.y"

  pik_error(p, 0, "parser stack overflow");
#line 1970 "pikchr.c"
/******** End %stack_overflow code ********************************************/
   pik_parserARG_STORE /* Suppress warning about unused %extra_argument var */
   pik_parserCTX_STORE
}

/*
** Print tracing information for a SHIFT action

  **     { ... }           // User supplied code
  **  #line <lineno> <thisfile>
  **     break;
  */
/********** Begin reduce actions **********************************************/
        YYMINORTYPE yylhsminor;
      case 0: /* document ::= statement_list */
#line 537 "pikchr.y"
{pik_render(p,yymsp[0].minor.yy227);}
#line 2452 "pikchr.c"
        break;
      case 1: /* statement_list ::= statement */
#line 540 "pikchr.y"
{ yylhsminor.yy227 = pik_elist_append(p,0,yymsp[0].minor.yy36); }
#line 2457 "pikchr.c"
  yymsp[0].minor.yy227 = yylhsminor.yy227;
        break;
      case 2: /* statement_list ::= statement_list EOL statement */
#line 542 "pikchr.y"
{ yylhsminor.yy227 = pik_elist_append(p,yymsp[-2].minor.yy227,yymsp[0].minor.yy36); }
#line 2463 "pikchr.c"
  yymsp[-2].minor.yy227 = yylhsminor.yy227;
        break;
      case 3: /* statement ::= */
#line 545 "pikchr.y"
{ yymsp[1].minor.yy36 = 0; }
#line 2469 "pikchr.c"
        break;
      case 4: /* statement ::= direction */
#line 546 "pikchr.y"
{ pik_set_direction(p,yymsp[0].minor.yy0.eCode);  yylhsminor.yy36=0; }
#line 2474 "pikchr.c"
  yymsp[0].minor.yy36 = yylhsminor.yy36;
        break;
      case 5: /* statement ::= lvalue ASSIGN rvalue */
#line 547 "pikchr.y"
{pik_set_var(p,&yymsp[-2].minor.yy0,yymsp[0].minor.yy153,&yymsp[-1].minor.yy0); yylhsminor.yy36=0;}
#line 2480 "pikchr.c"
  yymsp[-2].minor.yy36 = yylhsminor.yy36;
        break;
      case 6: /* statement ::= PLACENAME COLON unnamed_statement */
#line 549 "pikchr.y"
{ yylhsminor.yy36 = yymsp[0].minor.yy36;  pik_elem_setname(p,yymsp[0].minor.yy36,&yymsp[-2].minor.yy0); }
#line 2486 "pikchr.c"
  yymsp[-2].minor.yy36 = yylhsminor.yy36;
        break;
      case 7: /* statement ::= PLACENAME COLON position */
#line 551 "pikchr.y"
{ yylhsminor.yy36 = pik_elem_new(p,0,0,0);
                 if(yylhsminor.yy36){ yylhsminor.yy36->ptAt = yymsp[0].minor.yy79; pik_elem_setname(p,yylhsminor.yy36,&yymsp[-2].minor.yy0); }}
#line 2493 "pikchr.c"
  yymsp[-2].minor.yy36 = yylhsminor.yy36;
        break;
      case 8: /* statement ::= unnamed_statement */
#line 553 "pikchr.y"
{yylhsminor.yy36 = yymsp[0].minor.yy36;}
#line 2499 "pikchr.c"
  yymsp[0].minor.yy36 = yylhsminor.yy36;
        break;
      case 9: /* statement ::= print prlist */
#line 554 "pikchr.y"
{pik_append(p,"<br>\n",5); yymsp[-1].minor.yy36=0;}
#line 2505 "pikchr.c"
        break;
      case 10: /* statement ::= ASSERT LP expr EQ expr RP */
#line 559 "pikchr.y"
{yymsp[-5].minor.yy36=pik_assert(p,yymsp[-3].minor.yy153,&yymsp[-2].minor.yy0,yymsp[-1].minor.yy153);}
#line 2510 "pikchr.c"
        break;
      case 11: /* statement ::= ASSERT LP position EQ position RP */
#line 561 "pikchr.y"
{yymsp[-5].minor.yy36=pik_position_assert(p,&yymsp[-3].minor.yy79,&yymsp[-2].minor.yy0,&yymsp[-1].minor.yy79);}
#line 2515 "pikchr.c"
        break;
      case 12: /* statement ::= DEFINE ID CODEBLOCK */
#line 562 "pikchr.y"
{yymsp[-2].minor.yy36=0; pik_add_macro(p,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy0);}
#line 2520 "pikchr.c"
        break;
      case 13: /* rvalue ::= PLACENAME */
#line 573 "pikchr.y"
{yylhsminor.yy153 = pik_lookup_color(p,&yymsp[0].minor.yy0);}
#line 2525 "pikchr.c"
  yymsp[0].minor.yy153 = yylhsminor.yy153;
        break;
      case 14: /* pritem ::= FILL */
      case 15: /* pritem ::= COLOR */ yytestcase(yyruleno==15);
      case 16: /* pritem ::= THICKNESS */ yytestcase(yyruleno==16);
#line 578 "pikchr.y"
{pik_append_num(p,"",pik_value(p,yymsp[0].minor.yy0.z,yymsp[0].minor.yy0.n,0));}
#line 2533 "pikchr.c"
        break;
      case 17: /* pritem ::= rvalue */
#line 581 "pikchr.y"
{pik_append_num(p,"",yymsp[0].minor.yy153);}
#line 2538 "pikchr.c"
        break;
      case 18: /* pritem ::= STRING */
#line 582 "pikchr.y"
{pik_append_text(p,yymsp[0].minor.yy0.z+1,yymsp[0].minor.yy0.n-2,0);}
#line 2543 "pikchr.c"
        break;
      case 19: /* prsep ::= COMMA */
#line 583 "pikchr.y"
{pik_append(p, " ", 1);}
#line 2548 "pikchr.c"
        break;
      case 20: /* unnamed_statement ::= basetype attribute_list */
#line 586 "pikchr.y"
{yylhsminor.yy36 = yymsp[-1].minor.yy36; pik_after_adding_attributes(p,yylhsminor.yy36);}
#line 2553 "pikchr.c"
  yymsp[-1].minor.yy36 = yylhsminor.yy36;
        break;
      case 21: /* basetype ::= CLASSNAME */
#line 588 "pikchr.y"
{yylhsminor.yy36 = pik_elem_new(p,&yymsp[0].minor.yy0,0,0); }
#line 2559 "pikchr.c"
  yymsp[0].minor.yy36 = yylhsminor.yy36;
        break;
      case 22: /* basetype ::= STRING textposition */
#line 590 "pikchr.y"
{yymsp[-1].minor.yy0.eCode = yymsp[0].minor.yy164; yylhsminor.yy36 = pik_elem_new(p,0,&yymsp[-1].minor.yy0,0); }
#line 2565 "pikchr.c"
  yymsp[-1].minor.yy36 = yylhsminor.yy36;
        break;
      case 23: /* basetype ::= LB savelist statement_list RB */
#line 592 "pikchr.y"
{ p->list = yymsp[-2].minor.yy227; yymsp[-3].minor.yy36 = pik_elem_new(p,0,0,yymsp[-1].minor.yy227); if(yymsp[-3].minor.yy36) yymsp[-3].minor.yy36->errTok = yymsp[0].minor.yy0; }
#line 2571 "pikchr.c"
        break;
      case 24: /* savelist ::= */
#line 597 "pikchr.y"
{yymsp[1].minor.yy227 = p->list; p->list = 0;}
#line 2576 "pikchr.c"
        break;
      case 25: /* relexpr ::= expr */
#line 604 "pikchr.y"
{yylhsminor.yy10.rAbs = yymsp[0].minor.yy153; yylhsminor.yy10.rRel = 0;}
#line 2581 "pikchr.c"
  yymsp[0].minor.yy10 = yylhsminor.yy10;
        break;
      case 26: /* relexpr ::= expr PERCENT */
#line 605 "pikchr.y"
{yylhsminor.yy10.rAbs = 0; yylhsminor.yy10.rRel = yymsp[-1].minor.yy153/100;}
#line 2587 "pikchr.c"
  yymsp[-1].minor.yy10 = yylhsminor.yy10;
        break;
      case 27: /* optrelexpr ::= */
#line 607 "pikchr.y"
{yymsp[1].minor.yy10.rAbs = 0; yymsp[1].minor.yy10.rRel = 1.0;}
#line 2593 "pikchr.c"
        break;
      case 28: /* attribute_list ::= relexpr alist */
#line 609 "pikchr.y"
{pik_add_direction(p,0,&yymsp[-1].minor.yy10);}
#line 2598 "pikchr.c"
        break;
      case 29: /* attribute ::= numproperty relexpr */
#line 613 "pikchr.y"
{ pik_set_numprop(p,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy10); }
#line 2603 "pikchr.c"
        break;
      case 30: /* attribute ::= dashproperty expr */
#line 614 "pikchr.y"
{ pik_set_dashed(p,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy153); }
#line 2608 "pikchr.c"
        break;
      case 31: /* attribute ::= dashproperty */
#line 615 "pikchr.y"
{ pik_set_dashed(p,&yymsp[0].minor.yy0,0);  }
#line 2613 "pikchr.c"
        break;
      case 32: /* attribute ::= colorproperty rvalue */
#line 616 "pikchr.y"
{ pik_set_clrprop(p,&yymsp[-1].minor.yy0,yymsp[0].minor.yy153); }
#line 2618 "pikchr.c"
        break;
      case 33: /* attribute ::= go direction optrelexpr */
#line 617 "pikchr.y"
{ pik_add_direction(p,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy10);}
#line 2623 "pikchr.c"
        break;
      case 34: /* attribute ::= go direction even position */
#line 618 "pikchr.y"
{pik_evenwith(p,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy79);}
#line 2628 "pikchr.c"
        break;
      case 35: /* attribute ::= CLOSE */
#line 619 "pikchr.y"
{ pik_close_path(p,&yymsp[0].minor.yy0); }
#line 2633 "pikchr.c"
        break;
      case 36: /* attribute ::= CHOP */
#line 620 "pikchr.y"
{ p->cur->bChop = 1; }
#line 2638 "pikchr.c"
        break;
      case 37: /* attribute ::= FROM position */
#line 621 "pikchr.y"
{ pik_set_from(p,p->cur,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy79); }
#line 2643 "pikchr.c"
        break;
      case 38: /* attribute ::= TO position */
#line 622 "pikchr.y"
{ pik_add_to(p,p->cur,&yymsp[-1].minor.yy0,&yymsp[0].minor.yy79); }
#line 2648 "pikchr.c"
        break;
      case 39: /* attribute ::= THEN */
#line 623 "pikchr.y"
{ pik_then(p, &yymsp[0].minor.yy0, p->cur); }
#line 2653 "pikchr.c"
        break;
      case 40: /* attribute ::= THEN optrelexpr HEADING expr */
      case 42: /* attribute ::= GO optrelexpr HEADING expr */ yytestcase(yyruleno==42);
#line 625 "pikchr.y"
{pik_move_hdg(p,&yymsp[-2].minor.yy10,&yymsp[-1].minor.yy0,yymsp[0].minor.yy153,0,&yymsp[-3].minor.yy0);}
#line 2659 "pikchr.c"
        break;
      case 41: /* attribute ::= THEN optrelexpr EDGEPT */
      case 43: /* attribute ::= GO optrelexpr EDGEPT */ yytestcase(yyruleno==43);
#line 626 "pikchr.y"
{pik_move_hdg(p,&yymsp[-1].minor.yy10,0,0,&yymsp[0].minor.yy0,&yymsp[-2].minor.yy0);}
#line 2665 "pikchr.c"
        break;
      case 44: /* attribute ::= AT position */
#line 631 "pikchr.y"
{ pik_set_at(p,0,&yymsp[0].minor.yy79,&yymsp[-1].minor.yy0); }
#line 2670 "pikchr.c"
        break;
      case 45: /* attribute ::= SAME */
#line 633 "pikchr.y"
{pik_same(p,0,&yymsp[0].minor.yy0);}
#line 2675 "pikchr.c"
        break;
      case 46: /* attribute ::= SAME AS object */
#line 634 "pikchr.y"
{pik_same(p,yymsp[0].minor.yy36,&yymsp[-2].minor.yy0);}
#line 2680 "pikchr.c"
        break;
      case 47: /* attribute ::= STRING textposition */
#line 635 "pikchr.y"
{pik_add_txt(p,&yymsp[-1].minor.yy0,yymsp[0].minor.yy164);}
#line 2685 "pikchr.c"
        break;
      case 48: /* attribute ::= FIT */
#line 636 "pikchr.y"
{pik_size_to_fit(p,&yymsp[0].minor.yy0,3); }
#line 2690 "pikchr.c"
        break;
      case 49: /* attribute ::= BEHIND object */
#line 637 "pikchr.y"
{pik_behind(p,yymsp[0].minor.yy36);}
#line 2695 "pikchr.c"
        break;
      case 50: /* withclause ::= DOT_E edge AT position */
      case 51: /* withclause ::= edge AT position */ yytestcase(yyruleno==51);
#line 645 "pikchr.y"
{ pik_set_at(p,&yymsp[-2].minor.yy0,&yymsp[0].minor.yy79,&yymsp[-1].minor.yy0); }
#line 2701 "pikchr.c"
        break;
      case 52: /* numproperty ::= HEIGHT|WIDTH|RADIUS|DIAMETER|THICKNESS */
#line 649 "pikchr.y"
{yylhsminor.yy0 = yymsp[0].minor.yy0;}
#line 2706 "pikchr.c"
  yymsp[0].minor.yy0 = yylhsminor.yy0;
        break;
      case 53: /* boolproperty ::= CW */
#line 660 "pikchr.y"
{p->cur->cw = 1;}
#line 2712 "pikchr.c"
        break;
      case 54: /* boolproperty ::= CCW */
#line 661 "pikchr.y"
{p->cur->cw = 0;}
#line 2717 "pikchr.c"
        break;
      case 55: /* boolproperty ::= LARROW */
#line 662 "pikchr.y"
{p->cur->larrow=1; p->cur->rarrow=0; }
#line 2722 "pikchr.c"
        break;
      case 56: /* boolproperty ::= RARROW */
#line 663 "pikchr.y"
{p->cur->larrow=0; p->cur->rarrow=1; }
#line 2727 "pikchr.c"
        break;
      case 57: /* boolproperty ::= LRARROW */
#line 664 "pikchr.y"
{p->cur->larrow=1; p->cur->rarrow=1; }
#line 2732 "pikchr.c"
        break;
      case 58: /* boolproperty ::= INVIS */
#line 665 "pikchr.y"
{p->cur->sw = 0.0;}
#line 2737 "pikchr.c"
        break;
      case 59: /* boolproperty ::= THICK */
#line 666 "pikchr.y"
{p->cur->sw *= 1.5;}
#line 2742 "pikchr.c"
        break;
      case 60: /* boolproperty ::= THIN */
#line 667 "pikchr.y"
{p->cur->sw *= 0.67;}
#line 2747 "pikchr.c"
        break;
      case 61: /* boolproperty ::= SOLID */
#line 668 "pikchr.y"
{p->cur->sw = pik_value(p,"thickness",9,0);
                               p->cur->dotted = p->cur->dashed = 0.0;}
#line 2753 "pikchr.c"
        break;
      case 62: /* textposition ::= */
#line 671 "pikchr.y"
{yymsp[1].minor.yy164 = 0;}
#line 2758 "pikchr.c"
        break;
      case 63: /* textposition ::= textposition CENTER|LJUST|RJUST|ABOVE|BELOW|ITALIC|BOLD|ALIGNED|BIG|SMALL */
#line 674 "pikchr.y"
{yylhsminor.yy164 = (short int)pik_text_position(yymsp[-1].minor.yy164,&yymsp[0].minor.yy0);}
#line 2763 "pikchr.c"
  yymsp[-1].minor.yy164 = yylhsminor.yy164;
        break;
      case 64: /* position ::= expr COMMA expr */
#line 677 "pikchr.y"
{yylhsminor.yy79.x=yymsp[-2].minor.yy153; yylhsminor.yy79.y=yymsp[0].minor.yy153;}
#line 2769 "pikchr.c"
  yymsp[-2].minor.yy79 = yylhsminor.yy79;
        break;
      case 65: /* position ::= place PLUS expr COMMA expr */
#line 679 "pikchr.y"
{yylhsminor.yy79.x=yymsp[-4].minor.yy79.x+yymsp[-2].minor.yy153; yylhsminor.yy79.y=yymsp[-4].minor.yy79.y+yymsp[0].minor.yy153;}
#line 2775 "pikchr.c"
  yymsp[-4].minor.yy79 = yylhsminor.yy79;
        break;
      case 66: /* position ::= place MINUS expr COMMA expr */
#line 680 "pikchr.y"
{yylhsminor.yy79.x=yymsp[-4].minor.yy79.x-yymsp[-2].minor.yy153; yylhsminor.yy79.y=yymsp[-4].minor.yy79.y-yymsp[0].minor.yy153;}
#line 2781 "pikchr.c"
  yymsp[-4].minor.yy79 = yylhsminor.yy79;
        break;
      case 67: /* position ::= place PLUS LP expr COMMA expr RP */
#line 682 "pikchr.y"
{yylhsminor.yy79.x=yymsp[-6].minor.yy79.x+yymsp[-3].minor.yy153; yylhsminor.yy79.y=yymsp[-6].minor.yy79.y+yymsp[-1].minor.yy153;}
#line 2787 "pikchr.c"
  yymsp[-6].minor.yy79 = yylhsminor.yy79;
        break;
      case 68: /* position ::= place MINUS LP expr COMMA expr RP */
#line 684 "pikchr.y"
{yylhsminor.yy79.x=yymsp[-6].minor.yy79.x-yymsp[-3].minor.yy153; yylhsminor.yy79.y=yymsp[-6].minor.yy79.y-yymsp[-1].minor.yy153;}
#line 2793 "pikchr.c"
  yymsp[-6].minor.yy79 = yylhsminor.yy79;
        break;
      case 69: /* position ::= LP position COMMA position RP */
#line 685 "pikchr.y"
{yymsp[-4].minor.yy79.x=yymsp[-3].minor.yy79.x; yymsp[-4].minor.yy79.y=yymsp[-1].minor.yy79.y;}
#line 2799 "pikchr.c"
        break;
      case 70: /* position ::= LP position RP */
#line 686 "pikchr.y"
{yymsp[-2].minor.yy79=yymsp[-1].minor.yy79;}
#line 2804 "pikchr.c"
        break;
      case 71: /* position ::= expr between position AND position */
#line 688 "pikchr.y"
{yylhsminor.yy79 = pik_position_between(yymsp[-4].minor.yy153,yymsp[-2].minor.yy79,yymsp[0].minor.yy79);}
#line 2809 "pikchr.c"
  yymsp[-4].minor.yy79 = yylhsminor.yy79;
        break;
      case 72: /* position ::= expr LT position COMMA position GT */
#line 690 "pikchr.y"
{yylhsminor.yy79 = pik_position_between(yymsp[-5].minor.yy153,yymsp[-3].minor.yy79,yymsp[-1].minor.yy79);}
#line 2815 "pikchr.c"
  yymsp[-5].minor.yy79 = yylhsminor.yy79;
        break;
      case 73: /* position ::= expr ABOVE position */
#line 691 "pikchr.y"
{yylhsminor.yy79=yymsp[0].minor.yy79; yylhsminor.yy79.y += yymsp[-2].minor.yy153;}
#line 2821 "pikchr.c"
  yymsp[-2].minor.yy79 = yylhsminor.yy79;
        break;
      case 74: /* position ::= expr BELOW position */
#line 692 "pikchr.y"
{yylhsminor.yy79=yymsp[0].minor.yy79; yylhsminor.yy79.y -= yymsp[-2].minor.yy153;}
#line 2827 "pikchr.c"
  yymsp[-2].minor.yy79 = yylhsminor.yy79;
        break;
      case 75: /* position ::= expr LEFT OF position */
#line 693 "pikchr.y"
{yylhsminor.yy79=yymsp[0].minor.yy79; yylhsminor.yy79.x -= yymsp[-3].minor.yy153;}
#line 2833 "pikchr.c"
  yymsp[-3].minor.yy79 = yylhsminor.yy79;
        break;
      case 76: /* position ::= expr RIGHT OF position */
#line 694 "pikchr.y"
{yylhsminor.yy79=yymsp[0].minor.yy79; yylhsminor.yy79.x += yymsp[-3].minor.yy153;}
#line 2839 "pikchr.c"
  yymsp[-3].minor.yy79 = yylhsminor.yy79;
        break;
      case 77: /* position ::= expr ON HEADING EDGEPT OF position */
#line 696 "pikchr.y"
{yylhsminor.yy79 = pik_position_at_hdg(yymsp[-5].minor.yy153,&yymsp[-2].minor.yy0,yymsp[0].minor.yy79);}
#line 2845 "pikchr.c"
  yymsp[-5].minor.yy79 = yylhsminor.yy79;
        break;
      case 78: /* position ::= expr HEADING EDGEPT OF position */
#line 698 "pikchr.y"
{yylhsminor.yy79 = pik_position_at_hdg(yymsp[-4].minor.yy153,&yymsp[-2].minor.yy0,yymsp[0].minor.yy79);}
#line 2851 "pikchr.c"
  yymsp[-4].minor.yy79 = yylhsminor.yy79;
        break;
      case 79: /* position ::= expr EDGEPT OF position */
#line 700 "pikchr.y"
{yylhsminor.yy79 = pik_position_at_hdg(yymsp[-3].minor.yy153,&yymsp[-2].minor.yy0,yymsp[0].minor.yy79);}
#line 2857 "pikchr.c"
  yymsp[-3].minor.yy79 = yylhsminor.yy79;
        break;
      case 80: /* position ::= expr ON HEADING expr FROM position */
#line 702 "pikchr.y"
{yylhsminor.yy79 = pik_position_at_angle(yymsp[-5].minor.yy153,yymsp[-2].minor.yy153,yymsp[0].minor.yy79);}
#line 2863 "pikchr.c"
  yymsp[-5].minor.yy79 = yylhsminor.yy79;
        break;
      case 81: /* position ::= expr HEADING expr FROM position */
#line 704 "pikchr.y"
{yylhsminor.yy79 = pik_position_at_angle(yymsp[-4].minor.yy153,yymsp[-2].minor.yy153,yymsp[0].minor.yy79);}
#line 2869 "pikchr.c"
  yymsp[-4].minor.yy79 = yylhsminor.yy79;
        break;
      case 82: /* place ::= edge OF object */
#line 716 "pikchr.y"
{yylhsminor.yy79 = pik_place_of_elem(p,yymsp[0].minor.yy36,&yymsp[-2].minor.yy0);}
#line 2875 "pikchr.c"
  yymsp[-2].minor.yy79 = yylhsminor.yy79;
        break;
      case 83: /* place2 ::= object */
#line 717 "pikchr.y"
{yylhsminor.yy79 = pik_place_of_elem(p,yymsp[0].minor.yy36,0);}
#line 2881 "pikchr.c"
  yymsp[0].minor.yy79 = yylhsminor.yy79;
        break;
      case 84: /* place2 ::= object DOT_E edge */
#line 718 "pikchr.y"
{yylhsminor.yy79 = pik_place_of_elem(p,yymsp[-2].minor.yy36,&yymsp[0].minor.yy0);}
#line 2887 "pikchr.c"
  yymsp[-2].minor.yy79 = yylhsminor.yy79;
        break;
      case 85: /* place2 ::= NTH VERTEX OF object */
#line 719 "pikchr.y"
{yylhsminor.yy79 = pik_nth_vertex(p,&yymsp[-3].minor.yy0,&yymsp[-2].minor.yy0,yymsp[0].minor.yy36);}
#line 2893 "pikchr.c"
  yymsp[-3].minor.yy79 = yylhsminor.yy79;
        break;
      case 86: /* object ::= nth */
#line 731 "pikchr.y"
{yylhsminor.yy36 = pik_find_nth(p,0,&yymsp[0].minor.yy0);}
#line 2899 "pikchr.c"
  yymsp[0].minor.yy36 = yylhsminor.yy36;
        break;
      case 87: /* object ::= nth OF|IN object */
#line 732 "pikchr.y"
{yylhsminor.yy36 = pik_find_nth(p,yymsp[0].minor.yy36,&yymsp[-2].minor.yy0);}
#line 2905 "pikchr.c"
  yymsp[-2].minor.yy36 = yylhsminor.yy36;
        break;
      case 88: /* objectname ::= THIS */
#line 734 "pikchr.y"
{yymsp[0].minor.yy36 = p->cur;}
#line 2911 "pikchr.c"
        break;
      case 89: /* objectname ::= PLACENAME */
#line 735 "pikchr.y"
{yylhsminor.yy36 = pik_find_byname(p,0,&yymsp[0].minor.yy0);}
#line 2916 "pikchr.c"
  yymsp[0].minor.yy36 = yylhsminor.yy36;
        break;
      case 90: /* objectname ::= objectname DOT_U PLACENAME */
#line 737 "pikchr.y"
{yylhsminor.yy36 = pik_find_byname(p,yymsp[-2].minor.yy36,&yymsp[0].minor.yy0);}
#line 2922 "pikchr.c"
  yymsp[-2].minor.yy36 = yylhsminor.yy36;
        break;
      case 91: /* nth ::= NTH CLASSNAME */
#line 739 "pikchr.y"
{yylhsminor.yy0=yymsp[0].minor.yy0; yylhsminor.yy0.eCode = pik_nth_value(p,&yymsp[-1].minor.yy0); }
#line 2928 "pikchr.c"
  yymsp[-1].minor.yy0 = yylhsminor.yy0;
        break;
      case 92: /* nth ::= NTH LAST CLASSNAME */
#line 740 "pikchr.y"
{yylhsminor.yy0=yymsp[0].minor.yy0; yylhsminor.yy0.eCode = -pik_nth_value(p,&yymsp[-2].minor.yy0); }
#line 2934 "pikchr.c"
  yymsp[-2].minor.yy0 = yylhsminor.yy0;
        break;
      case 93: /* nth ::= LAST CLASSNAME */
#line 741 "pikchr.y"
{yymsp[-1].minor.yy0=yymsp[0].minor.yy0; yymsp[-1].minor.yy0.eCode = -1;}
#line 2940 "pikchr.c"
        break;
      case 94: /* nth ::= LAST */
#line 742 "pikchr.y"
{yylhsminor.yy0=yymsp[0].minor.yy0; yylhsminor.yy0.eCode = -1;}
#line 2945 "pikchr.c"
  yymsp[0].minor.yy0 = yylhsminor.yy0;
        break;
      case 95: /* nth ::= NTH LB RB */
#line 743 "pikchr.y"
{yylhsminor.yy0=yymsp[-1].minor.yy0; yylhsminor.yy0.eCode = pik_nth_value(p,&yymsp[-2].minor.yy0);}
#line 2951 "pikchr.c"
  yymsp[-2].minor.yy0 = yylhsminor.yy0;
        break;
      case 96: /* nth ::= NTH LAST LB RB */
#line 744 "pikchr.y"
{yylhsminor.yy0=yymsp[-1].minor.yy0; yylhsminor.yy0.eCode = -pik_nth_value(p,&yymsp[-3].minor.yy0);}
#line 2957 "pikchr.c"
  yymsp[-3].minor.yy0 = yylhsminor.yy0;
        break;
      case 97: /* nth ::= LAST LB RB */
#line 745 "pikchr.y"
{yymsp[-2].minor.yy0=yymsp[-1].minor.yy0; yymsp[-2].minor.yy0.eCode = -1; }
#line 2963 "pikchr.c"
        break;
      case 98: /* expr ::= expr PLUS expr */
#line 747 "pikchr.y"
{yylhsminor.yy153=yymsp[-2].minor.yy153+yymsp[0].minor.yy153;}
#line 2968 "pikchr.c"
  yymsp[-2].minor.yy153 = yylhsminor.yy153;
        break;
      case 99: /* expr ::= expr MINUS expr */
#line 748 "pikchr.y"
{yylhsminor.yy153=yymsp[-2].minor.yy153-yymsp[0].minor.yy153;}
#line 2974 "pikchr.c"
  yymsp[-2].minor.yy153 = yylhsminor.yy153;
        break;
      case 100: /* expr ::= expr STAR expr */
#line 749 "pikchr.y"
{yylhsminor.yy153=yymsp[-2].minor.yy153*yymsp[0].minor.yy153;}
#line 2980 "pikchr.c"
  yymsp[-2].minor.yy153 = yylhsminor.yy153;
        break;
      case 101: /* expr ::= expr SLASH expr */
#line 750 "pikchr.y"
{
  if( yymsp[0].minor.yy153==0.0 ){ pik_error(p, &yymsp[-1].minor.yy0, "division by zero"); yylhsminor.yy153 = 0.0; }
  else{ yylhsminor.yy153 = yymsp[-2].minor.yy153/yymsp[0].minor.yy153; }
}
#line 2989 "pikchr.c"
  yymsp[-2].minor.yy153 = yylhsminor.yy153;
        break;
      case 102: /* expr ::= MINUS expr */
#line 754 "pikchr.y"
{yymsp[-1].minor.yy153=-yymsp[0].minor.yy153;}
#line 2995 "pikchr.c"
        break;
      case 103: /* expr ::= PLUS expr */
#line 755 "pikchr.y"
{yymsp[-1].minor.yy153=yymsp[0].minor.yy153;}
#line 3000 "pikchr.c"
        break;
      case 104: /* expr ::= LP expr RP */
#line 756 "pikchr.y"
{yymsp[-2].minor.yy153=yymsp[-1].minor.yy153;}
#line 3005 "pikchr.c"
        break;
      case 105: /* expr ::= LP FILL|COLOR|THICKNESS RP */
#line 757 "pikchr.y"
{yymsp[-2].minor.yy153=pik_get_var(p,&yymsp[-1].minor.yy0);}
#line 3010 "pikchr.c"
        break;
      case 106: /* expr ::= NUMBER */
#line 758 "pikchr.y"
{yylhsminor.yy153=pik_atof(&yymsp[0].minor.yy0);}
#line 3015 "pikchr.c"
  yymsp[0].minor.yy153 = yylhsminor.yy153;
        break;
      case 107: /* expr ::= ID */
#line 759 "pikchr.y"
{yylhsminor.yy153=pik_get_var(p,&yymsp[0].minor.yy0);}
#line 3021 "pikchr.c"
  yymsp[0].minor.yy153 = yylhsminor.yy153;
        break;
      case 108: /* expr ::= FUNC1 LP expr RP */
#line 760 "pikchr.y"
{yylhsminor.yy153 = pik_func(p,&yymsp[-3].minor.yy0,yymsp[-1].minor.yy153,0.0);}
#line 3027 "pikchr.c"
  yymsp[-3].minor.yy153 = yylhsminor.yy153;
        break;
      case 109: /* expr ::= FUNC2 LP expr COMMA expr RP */
#line 761 "pikchr.y"
{yylhsminor.yy153 = pik_func(p,&yymsp[-5].minor.yy0,yymsp[-3].minor.yy153,yymsp[-1].minor.yy153);}
#line 3033 "pikchr.c"
  yymsp[-5].minor.yy153 = yylhsminor.yy153;
        break;
      case 110: /* expr ::= DIST LP position COMMA position RP */
#line 762 "pikchr.y"
{yymsp[-5].minor.yy153 = pik_dist(&yymsp[-3].minor.yy79,&yymsp[-1].minor.yy79);}
#line 3039 "pikchr.c"
        break;
      case 111: /* expr ::= place2 DOT_XY X */
#line 763 "pikchr.y"
{yylhsminor.yy153 = yymsp[-2].minor.yy79.x;}
#line 3044 "pikchr.c"
  yymsp[-2].minor.yy153 = yylhsminor.yy153;
        break;
      case 112: /* expr ::= place2 DOT_XY Y */
#line 764 "pikchr.y"
{yylhsminor.yy153 = yymsp[-2].minor.yy79.y;}
#line 3050 "pikchr.c"
  yymsp[-2].minor.yy153 = yylhsminor.yy153;
        break;
      case 113: /* expr ::= object DOT_L numproperty */
      case 114: /* expr ::= object DOT_L dashproperty */ yytestcase(yyruleno==114);
      case 115: /* expr ::= object DOT_L colorproperty */ yytestcase(yyruleno==115);
#line 765 "pikchr.y"
{yylhsminor.yy153=pik_property_of(yymsp[-2].minor.yy36,&yymsp[0].minor.yy0);}
#line 3058 "pikchr.c"
  yymsp[-2].minor.yy153 = yylhsminor.yy153;
        break;
      default:
      /* (116) lvalue ::= ID */ yytestcase(yyruleno==116);
      /* (117) lvalue ::= FILL */ yytestcase(yyruleno==117);
      /* (118) lvalue ::= COLOR */ yytestcase(yyruleno==118);
      /* (119) lvalue ::= THICKNESS */ yytestcase(yyruleno==119);

  int yymajor,                   /* The major type of the error token */
  pik_parserTOKENTYPE yyminor         /* The minor type of the error token */
){
  pik_parserARG_FETCH
  pik_parserCTX_FETCH
#define TOKEN yyminor
/************ Begin %syntax_error code ****************************************/
#line 525 "pikchr.y"

  if( TOKEN.z && TOKEN.z[0] ){
    pik_error(p, &TOKEN, "syntax error");
  }else{
    pik_error(p, 0, "syntax error");
  }
  UNUSED_PARAMETER(yymajor);
#line 3169 "pikchr.c"
/************ End %syntax_error code ******************************************/
  pik_parserARG_STORE /* Suppress warning about unused %extra_argument variable */
  pik_parserCTX_STORE
}

/*
** The following is executed when the parser accepts

  assert( iToken<(int)(sizeof(yyFallback)/sizeof(yyFallback[0])) );
  return yyFallback[iToken];
#else
  (void)iToken;
  return 0;
#endif
}
#line 770 "pikchr.y"



/* Chart of the 148 official CSS color names with their
** corresponding RGB values thru Color Module Level 4:
** https://developer.mozilla.org/en-US/docs/Web/CSS/color_value
**

       if( p->mTPath & 1 ) n = pik_next_rpath(p, pDir);
       p->aTPath[n].x = pPlace->x;
       p->mTPath |= 1;
       break;
  }
  pObj->outDir = pDir->eCode;
}

/* If the last referenced object is centered at point pPt then return
** a pointer to that object.  If there is no prior object reference,
** or if the points are not the same, return NULL.
**
** This is a side-channel hack used to find the objects at which a
** line begins and ends.  For example, in
**
**        arrow from OBJ1 to OBJ2 chop
**
** The arrow object is normally just handed the coordinates of the
** centers for OBJ1 and OBJ2.  But we also want to know the specific
** object named in case there are multiple objects centered at the
** same point.
**
** See forum post 1d46e3a0bc
*/
static PObj *pik_last_ref_object(Pik *p, PPoint *pPt){
  PObj *pRes = 0;
  if( p->lastRef==0 ) return 0;
  if( p->lastRef->ptAt.x==pPt->x
   && p->lastRef->ptAt.y==pPt->y
  ){
    pRes = p->lastRef;
  }
  p->lastRef = 0;
  return pRes;
}

/* Set the "from" of an object
*/
static void pik_set_from(Pik *p, PObj *pObj, PToken *pTk, PPoint *pPt){
  if( !pObj->type->isLine ){
    pik_error(p, pTk, "use \"at\" to position this object");
    return;

      p->aTPath[i].x += dx;
      p->aTPath[i].y += dy;
    }
  }
  p->aTPath[0] = *pPt;
  p->mTPath = 3;
  pObj->mProp |= A_FROM;
  pObj->pFrom = pik_last_ref_object(p, pPt);
}

/* Set the "to" of an object
*/
static void pik_add_to(Pik *p, PObj *pObj, PToken *pTk, PPoint *pPt){
  int n = p->nTPath-1;
  if( !pObj->type->isLine ){
    pik_error(p, pTk, "use \"at\" to position this object");
    return;
  }
  if( pObj->bClose ){
    pik_error(p, pTk, "polygon is closed");
    return;
  }
  pik_reset_samepath(p);
  if( n==0 || p->mTPath==3 || p->thenFlag ){
    n = pik_next_rpath(p, pTk);
  }
  p->aTPath[n] = *pPt;
  p->mTPath = 3;
  pObj->pTo = pik_last_ref_object(p, pPt);
}

static void pik_close_path(Pik *p, PToken *pErr){
  PObj *pObj = p->cur;
  if( p->nTPath<3 ){
    pik_error(p, pErr,
      "need at least 3 vertexes in order to close the polygon");

    pik_error(p, pName, "no such object");
    return 0;
  }
  /* First look explicitly tagged objects */
  for(i=pList->n-1; i>=0; i--){
    PObj *pObj = pList->a[i];
    if( pObj->zName && pik_token_eq(pName,pObj->zName)==0 ){
      p->lastRef = pObj;
      return pObj;
    }
  }
  /* If not found, do a second pass looking for any object containing
  ** text which exactly matches pName */
  for(i=pList->n-1; i>=0; i--){
    PObj *pObj = pList->a[i];
    for(j=0; j<pObj->nTxt; j++){
      if( pObj->aTxt[j].n==pName->n+2
       && memcmp(pObj->aTxt[j].z+1,pName->z,pName->n)==0 ){
        p->lastRef = pObj;
        return pObj;
      }
    }
  }
  pik_error(p, pName, "no such object");
  return 0;
}

/*
** There is a line traveling from pFrom to pTo.
**
** If point pTo is the exact enter of a choppable object,
** then adjust pTo by the appropriate amount in the direction
** of pFrom.
*/
static void pik_autochop(Pik *p, PPoint *pFrom, PPoint *pTo, PObj *pObj){
  if( pObj==0 || pObj->type->xChop==0 ){
    pObj = pik_find_chopper(p->list, pTo, pFrom);
  }
  if( pObj ){
    *pTo = pObj->type->xChop(p, pObj, pFrom);
  }
}

/* This routine runs after all attributes have been received
** on an object.

    /* "chop" processing:
    ** If the line goes to the center of an object with an
    ** xChop method, then use the xChop method to trim the line.
    */
    if( pObj->bChop && pObj->nPath>=2 ){
      int n = pObj->nPath;
      pik_autochop(p, &pObj->aPath[n-2], &pObj->aPath[n-1], pObj->pTo);
      pik_autochop(p, &pObj->aPath[1], &pObj->aPath[0], pObj->pFrom);
    }

    pObj->ptEnter = pObj->aPath[0];
    pObj->ptExit = pObj->aPath[pObj->nPath-1];

    /* Compute the center of the line based on the bounding box over
    ** the vertexes.  This is a difference from PIC.  In Pikchr, the

  return TCL_OK;
}


#endif /* PIKCHR_TCL */


#line 8107 "pikchr.c"

  unsigned mProp;          /* Masks of properties set so far */
  unsigned mCalc;          /* Values computed from other constraints */
  PToken aTxt[5];          /* Text with .eCode holding TP flags */
  int iLayer;              /* Rendering order */
  int inDir, outDir;       /* Entry and exit directions */
  int nPath;               /* Number of path points */
  PPoint *aPath;           /* Array of path points */
  PObj *pFrom, *pTo;       /* End-point objects of a path */
  PBox bbox;               /* Bounding box */
};

/* A list of graphics objects */
struct PList {
  int n;          /* Number of statements in the list */
  int nAlloc;     /* Allocated slots in a[] */

  PToken sIn;              /* Input Pikchr-language text */
  char *zOut;              /* Result accumulates here */
  unsigned int nOut;       /* Bytes written to zOut[] so far */
  unsigned int nOutAlloc;  /* Space allocated to zOut[] */
  unsigned char eDir;      /* Current direction */
  unsigned int mFlags;     /* Flags passed to pikchr() */
  PObj *cur;               /* Object under construction */
  PObj *lastRef;           /* Last object references by "place" */
  PList *list;             /* Object list under construction */
  PMacro *pMacros;         /* List of all defined macros */
  PVar *pVar;              /* Application-defined variables */
  PBox bbox;               /* Bounding box around all statements */
                           /* Cache of layout values.  <=0.0 for unknown... */
  PNum rScale;                 /* Multiply to convert inches to pixels */
  PNum fontScale;              /* Scale fonts by this percent */

       if( p->mTPath & 1 ) n = pik_next_rpath(p, pDir);
       p->aTPath[n].x = pPlace->x;
       p->mTPath |= 1;
       break;
  }
  pObj->outDir = pDir->eCode;
}

/* If the last referenced object is centered at point pPt then return
** a pointer to that object.  If there is no prior object reference,
** or if the points are not the same, return NULL.
**
** This is a side-channel hack used to find the objects at which a
** line begins and ends.  For example, in
**
**        arrow from OBJ1 to OBJ2 chop
**
** The arrow object is normally just handed the coordinates of the
** centers for OBJ1 and OBJ2.  But we also want to know the specific
** object named in case there are multiple objects centered at the
** same point.
**
** See forum post 1d46e3a0bc
*/
static PObj *pik_last_ref_object(Pik *p, PPoint *pPt){
  PObj *pRes = 0;
  if( p->lastRef==0 ) return 0;
  if( p->lastRef->ptAt.x==pPt->x
   && p->lastRef->ptAt.y==pPt->y
  ){
    pRes = p->lastRef;
  }
  p->lastRef = 0;
  return pRes;
}

/* Set the "from" of an object
*/
static void pik_set_from(Pik *p, PObj *pObj, PToken *pTk, PPoint *pPt){
  if( !pObj->type->isLine ){
    pik_error(p, pTk, "use \"at\" to position this object");
    return;

      p->aTPath[i].x += dx;
      p->aTPath[i].y += dy;
    }
  }
  p->aTPath[0] = *pPt;
  p->mTPath = 3;
  pObj->mProp |= A_FROM;
  pObj->pFrom = pik_last_ref_object(p, pPt);
}

/* Set the "to" of an object
*/
static void pik_add_to(Pik *p, PObj *pObj, PToken *pTk, PPoint *pPt){
  int n = p->nTPath-1;
  if( !pObj->type->isLine ){
    pik_error(p, pTk, "use \"at\" to position this object");
    return;
  }
  if( pObj->bClose ){
    pik_error(p, pTk, "polygon is closed");
    return;
  }
  pik_reset_samepath(p);
  if( n==0 || p->mTPath==3 || p->thenFlag ){
    n = pik_next_rpath(p, pTk);
  }
  p->aTPath[n] = *pPt;
  p->mTPath = 3;
  pObj->pTo = pik_last_ref_object(p, pPt);
}

static void pik_close_path(Pik *p, PToken *pErr){
  PObj *pObj = p->cur;
  if( p->nTPath<3 ){
    pik_error(p, pErr,
      "need at least 3 vertexes in order to close the polygon");

    pik_error(p, pName, "no such object");
    return 0;
  }
  /* First look explicitly tagged objects */
  for(i=pList->n-1; i>=0; i--){
    PObj *pObj = pList->a[i];
    if( pObj->zName && pik_token_eq(pName,pObj->zName)==0 ){
      p->lastRef = pObj;
      return pObj;
    }
  }
  /* If not found, do a second pass looking for any object containing
  ** text which exactly matches pName */
  for(i=pList->n-1; i>=0; i--){
    PObj *pObj = pList->a[i];
    for(j=0; j<pObj->nTxt; j++){
      if( pObj->aTxt[j].n==pName->n+2
       && memcmp(pObj->aTxt[j].z+1,pName->z,pName->n)==0 ){
        p->lastRef = pObj;
        return pObj;
      }
    }
  }
  pik_error(p, pName, "no such object");
  return 0;
}

/*
** There is a line traveling from pFrom to pTo.
**
** If point pTo is the exact enter of a choppable object,
** then adjust pTo by the appropriate amount in the direction
** of pFrom.
*/
static void pik_autochop(Pik *p, PPoint *pFrom, PPoint *pTo, PObj *pObj){
  if( pObj==0 || pObj->type->xChop==0 ){
    pObj = pik_find_chopper(p->list, pTo, pFrom);
  }
  if( pObj ){
    *pTo = pObj->type->xChop(p, pObj, pFrom);
  }
}

/* This routine runs after all attributes have been received
** on an object.

    /* "chop" processing:
    ** If the line goes to the center of an object with an
    ** xChop method, then use the xChop method to trim the line.
    */
    if( pObj->bChop && pObj->nPath>=2 ){
      int n = pObj->nPath;
      pik_autochop(p, &pObj->aPath[n-2], &pObj->aPath[n-1], pObj->pTo);
      pik_autochop(p, &pObj->aPath[1], &pObj->aPath[0], pObj->pFrom);
    }

    pObj->ptEnter = pObj->aPath[0];
    pObj->ptExit = pObj->aPath[pObj->nPath-1];

    /* Compute the center of the line based on the bounding box over
    ** the vertexes.  This is a difference from PIC.  In Pikchr, the

circle "C0" fit color blue
C1: circle at C0 radius 2.5*C0.radius color red
text "C1" with .n at C1.n color red
circle "X1" at 8*C0.radius heading 60 from C0 fit color blue
circle "X2" at 8*C0.radius heading 80 from C0 fit color red
circle "X3" at 8*C0.radius heading 100 from C0 fit color blue
circle "X4" at 8*C0.radius heading 120 from C0 fit color red
arrow color blue from C0 to X1 chop
arrow color red from C1 to X2 chop
arrow color blue from X3 to C0 chop
arrow color red from X4 to C1 chop

text "chop bug 2021-07-17" \
     "forum 1d46e3a0bc5c5631" \
     "red lines to red circles" \
     "blue lines to blue circle" \
     at 2cm below C0