implement Polyhedra; include "sys.m";	sys: Sys;include "bufio.m";	bufio: Bufio;	Iobuf: import bufio;include "math/polyhedra.m"; scanpolyhedra(f: string): (int, ref Polyhedron, ref Iobuf){	first, last: ref Polyhedron;	D: int; 	if(sys == nil)		sys = load Sys Sys->PATH;	if(bufio == nil)		bufio = load Bufio Bufio->PATH;	b := bufio->open(f, Sys->OREAD);	if(b == nil)		return (0, nil, nil);	n := 0;	for(;;){		s := getstring(b);		if(s == nil)			break;		n++;		p := ref Polyhedron;		if(first == nil)			first = p;		else{			last.nxt = p;			p.prv = last;		}		last = p;		p.name = s;		p.dname = getstring(b);		b.gets('\n');		(p.allf, p.adj) = scanvc(getstring(b));		b.gets('\n');		b.gets('\n');		b.gets('\n');		l := getstring(b);		(p.indx, l) = getint(l);		(p.V, l) = getint(l);		(p.E, l) = getint(l);		(p.F, l) = getint(l);		(nil, l) = getint(l);		(D, l) = getint(l);		(p.anti, l) = getint(l);		p.concave = D != 1 || p.allf;		p.offset = b.offset();		tot := 2*p.V+2*p.F;		for(i := 0; i < tot; i++)			b.gets('\n');		if(p.indx < 58 || p.indx == 59 || p.indx == 66 || p.indx == 67)			p.inc = 0.1;		else			p.inc = 0.0;		# sys->print("%d:	%d %d %d %d %s\n", p.indx, p.allf, D != 1, p.anti, p.concave, vc);	}	first.prv = last;	last.nxt = first;	return (n, first, b);} getpolyhedra(p: ref Polyhedron, b: ref Iobuf){	q := p;	do{		getpolyhedron(q, b);		q = q.nxt;	}while(q != p);	} getpolyhedron(p: ref Polyhedron, b: ref Iobuf){	if(p.v != nil)		return;	b.seek(p.offset, Bufio->SEEKSTART);	p.v = array[p.V] of Vector;	for(i := 0; i < p.V; i++)		p.v[i] = getvector(b);	p.f = array[p.F] of Vector;	for(i = 0; i < p.F; i++)		p.f[i] = getvector(b);	p.fv = array[p.F] of array of int;	for(i = 0; i < p.F; i++)		p.fv[i] = getarray(b, p.adj);	p.vf = array[p.V] of array of int;	for(i = 0; i < p.V; i++)		p.vf[i] = getarray(b, p.adj);} getstring(b: ref Iobuf): string{	s := b.gets('\n');	if(s == nil)		return nil;	if(s[0] == '#')		return getstring(b);	if(s[len s - 1] == '\n')		return s[0: len s - 1];	return s;} getvector(b: ref Iobuf): Vector{	v: Vector; 	s := getstring(b);	(v.x, s) = getreal(s);	(v.y, s) = getreal(s);	(v.z, s) = getreal(s);	return v;} getarray(b: ref Iobuf, adj: int): array of int{	n, d: int; 	s := getstring(b);	(n, s) = getint(s);	a := array[n+2] of int;	a[0] = n;	for(i := 1; i <= n; i++)		(a[i], s) = getint(s);	(d, s) = getint(s);	if(d == 0 || d == n-1 || adj)		d = 1;	a[n+1] = d;	return a;} getint(s: string): (int, string){	n := int s;	for(i := 0; i < len s && s[i] == ' '; i++)		;	for( ; i < len s; i++)		if(s[i] == ' ')			return (n, s[i+1:]);	return (n, nil);} getreal(s: string): (real, string){	r := real s;	for(i := 0; i < len s && s[i] == ' '; i++)		;	for( ; i < len s; i++)		if(s[i] == ' ')			return (r, s[i+1:]);	return (r, nil);} vftab := array[] of { 0, 0, 0, 2, 3, 3, 5, 0, 3, 0, 3 }; scanvc(s: string): (int, int){	af := 0;	ad := 0;	fd := ld := 1;	ln := len s;	if(ln > 0 && s[0] == '('){		s = s[1:];		ln--;	}	while(ln > 0 && s[ln-1] != ')'){		s = s[0: ln-1];		ln--;	}	(m, lst) := sys->tokenize(s, ".");	for(l := lst ; l != nil; l = tl l){		(m, lst) = sys->tokenize(hd l, "/");		if(m == 1)			(n, d) := (int hd lst, 1);		else if(m == 2)			(n, d) = (int hd lst, int hd tl lst);		else			sys->print("vc error\n");		if(d != 1 && d == vftab[n])			af = 1;		if(d == n-1)			d = 1;		if(l == lst)			fd = d;		else if(ld != 1 && d != 1)			ad = 1;		ld = d;	}	if(ld != 1 && fd != 1)		ad = 1;	return (af, ad);}