src/gen/genworm.c

#ifndef lint
static const char       RCSid[] = "$Id: genworm.c,v 2.10 2018/05/04 23:56:49 greg Exp $";
#endif
/*
 *  genworm.c - program to generate worms (strings with varying thickness).
 *
 *      The program takes as input the functions of t for x, y,
 *      z and r (the radius).  Cylinders and cones will be
 *      joined by spheres.  Negative radii are forbidden.
 *
 *      9/24/87
 */

#include  <stdlib.h>
#include  <stdio.h>
#include  <math.h>
#include  <string.h>

#include  "calcomp.h"
#include  "rtio.h"
#include  "resolu.h"
#include  "rterror.h"
#include  "fvect.h"

#define  XNAME          "X`SYS`"                /* x function name */
#define  YNAME          "Y`SYS`"                /* y function name */
#define  ZNAME          "Z`SYS`"                /* z function name */
#define  RNAME          "R`SYS`"                /* r function name */

#define  PI             3.14159265358979323846

#define  max(a,b)       ((a) > (b) ? (a) : (b))


/* XXX redundant, move to library */
double  l_hermite(char *), l_bezier(char *), l_bspline(char *);


int
main(argc, argv)
int  argc;
char  *argv[];
{
        char  stmp[256];
        double  t, f, lastr = 0, r;
        FVECT  lastp, p;
        int  i, nseg;

        esupport |= E_VARIABLE|E_FUNCTION|E_RCONST;
        esupport &= ~(E_OUTCHAN|E_INCHAN);
        varset("PI", ':', PI);
        funset("hermite", 5, ':', l_hermite);
        funset("bezier", 5, ':', l_bezier);
        funset("bspline", 5, ':', l_bspline);

        if (argc < 8)
                goto userror;

        for (i = 8; i < argc; i++)
                if (!strcmp(argv[i], "-e"))
                        scompile(argv[++i], NULL, 0);
                else if (!strcmp(argv[i], "-f")) {
                        char  *fpath = getpath(argv[++i], getrlibpath(), 0);
                        if (fpath == NULL) {
                                fprintf(stderr, "%s: cannot find file '%s'\n",
                                                argv[0], argv[i]);
                                quit(1);
                        }
                        fcompile(fpath);
                } else
                        goto userror;

        sprintf(stmp, "%s(t)=%s;", XNAME, argv[3]);
        scompile(stmp, NULL, 0);
        sprintf(stmp, "%s(t)=%s;", YNAME, argv[4]);
        scompile(stmp, NULL, 0);
        sprintf(stmp, "%s(t)=%s;", ZNAME, argv[5]);
        scompile(stmp, NULL, 0);
        sprintf(stmp, "%s(t)=%s;", RNAME, argv[6]);
        scompile(stmp, NULL, 0);
        nseg = eval(argv[7]) + .5;
        if (nseg <= 0)
                goto userror;

        fputs("# ", stdout);
        printargs(argc, argv, stdout);
        eclock = 0;

        for (i = 0; i <= nseg; i++) {
                t = (double)i/nseg;
                p[0] = funvalue(XNAME, 1, &t);
                p[1] = funvalue(YNAME, 1, &t);
                p[2] = funvalue(ZNAME, 1, &t);
                r = funvalue(RNAME, 1, &t);
                if (i) {
                        if (lastr <= r+FTINY && lastr >= r-FTINY) {
                                printf("\n%s cylinder %s.c%d\n",
                                                argv[1], argv[2], i);
                                printf("0\n0\n7\n");
                                printf("%18.12g %18.12g %18.12g\n",
                                                lastp[0], lastp[1], lastp[2]);
                                printf("%18.12g %18.12g %18.12g\n",
                                                p[0], p[1], p[2]);
                                printf("%18.12g\n", r);
                        } else {
                                printf("\n%s cone %s.c%d\n",
                                                argv[1], argv[2], i);
                                printf("0\n0\n8\n");
                                f = (lastr - r)/dist2(lastp,p);
                                printf("%18.12g %18.12g %18.12g\n",
                                        lastp[0] + f*lastr*(p[0] - lastp[0]),
                                        lastp[1] + f*lastr*(p[1] - lastp[1]),
                                        lastp[2] + f*lastr*(p[2] - lastp[2]));
                                printf("%18.12g %18.12g %18.12g\n",
                                        p[0] + f*r*(p[0] - lastp[0]),
                                        p[1] + f*r*(p[1] - lastp[1]),
                                        p[2] + f*r*(p[2] - lastp[2]));
                                f = 1.0 - (lastr-r)*f;
                                f = f <= 0.0 ? 0.0 : sqrt(f);
                                printf("%18.12g %18.12g\n", f*lastr, f*r);
                        }
                }
                printf("\n%s sphere %s.s%d\n", argv[1], argv[2], i);
                printf("0\n0\n4 %18.12g %18.12g %18.12g %18.12g\n",
                                p[0], p[1], p[2], r);
                VCOPY(lastp, p);
                lastr = r;
        }
        return 0;

userror:
        fprintf(stderr,
"Usage: %s material name x(t) y(t) z(t) r(t) nseg [-e expr] [-f file]\n",
                        argv[0]);
        return 1;
}


double
l_hermite(char *nm)
{
        double  t;
        
        t = argument(5);
        return( argument(1)*((2.0*t-3.0)*t*t+1.0) +
                argument(2)*(-2.0*t+3.0)*t*t +
                argument(3)*((t-2.0)*t+1.0)*t +
                argument(4)*(t-1.0)*t*t );
}


double
l_bezier(char *nm)
{
        double  t;

        t = argument(5);
        return( argument(1) * (1.+t*(-3.+t*(3.-t))) +
                argument(2) * 3.*t*(1.+t*(-2.+t)) +
                argument(3) * 3.*t*t*(1.-t) +
                argument(4) * t*t*t );
}


double
l_bspline(char *nm)
{
        double  t;

        t = argument(5);
        return( argument(1) * (1./6.+t*(-1./2.+t*(1./2.-1./6.*t))) +
                argument(2) * (2./3.+t*t*(-1.+1./2.*t)) +
                argument(3) * (1./6.+t*(1./2.+t*(1./2.-1./2.*t))) +
                argument(4) * (1./6.*t*t*t) );
}
Revision:	2.11
Committed:	Sat Dec 7 02:21:42 2019 UTC (4 years, 4 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.10:	+2 -2 lines
Log Message:	Changed gen{worm,surf,rev} to accept expressions for number of segments
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	greg	2.11	static const char RCSid[] = "$Id: genworm.c,v 2.10 2018/05/04 23:56:49 greg Exp $";
3	greg	1.1	#endif
4	greg	1.2	/*
5	greg	1.1	* genworm.c - program to generate worms (strings with varying thickness).
6			*
7			* The program takes as input the functions of t for x, y,
8			* z and r (the radius). Cylinders and cones will be
9			* joined by spheres. Negative radii are forbidden.
10			*
11			* 9/24/87
12			*/
13
14	schorsch	2.7	#include <stdlib.h>
15	greg	1.1	#include <stdio.h>
16	greg	2.2	#include <math.h>
17	schorsch	2.7	#include <string.h>
18
19	greg	2.6	#include "calcomp.h"
20	greg	2.10	#include "rtio.h"
21	greg	2.8	#include "resolu.h"
22			#include "rterror.h"
23	greg	1.1	#include "fvect.h"
24
25	greg	1.9	#define XNAME "X`SYS`" /* x function name */
26			#define YNAME "Y`SYS`" /* y function name */
27			#define ZNAME "Z`SYS`" /* z function name */
28			#define RNAME "R`SYS`" /* r function name */
29	greg	1.1
30			#define PI 3.14159265358979323846
31
32			#define max(a,b) ((a) > (b) ? (a) : (b))
33
34
35	schorsch	2.7	/* XXX redundant, move to library */
36	greg	2.6	double l_hermite(char ), l_bezier(char ), l_bspline(char *);
37	greg	1.1
38
39	schorsch	2.7	int
40	greg	1.1	main(argc, argv)
41			int argc;
42			char *argv[];
43			{
44			char stmp[256];
45	schorsch	2.7	double t, f, lastr = 0, r;
46	greg	1.1	FVECT lastp, p;
47			int i, nseg;
48
49	greg	2.9	esupport \|= E_VARIABLE\|E_FUNCTION\|E_RCONST;
50			esupport &= ~(E_OUTCHAN\|E_INCHAN);
51	greg	1.7	varset("PI", ':', PI);
52	greg	1.8	funset("hermite", 5, ':', l_hermite);
53			funset("bezier", 5, ':', l_bezier);
54			funset("bspline", 5, ':', l_bspline);
55	greg	1.1
56			if (argc < 8)
57			goto userror;
58
59			for (i = 8; i < argc; i++)
60			if (!strcmp(argv[i], "-e"))
61	greg	1.6	scompile(argv[++i], NULL, 0);
62	greg	2.10	else if (!strcmp(argv[i], "-f")) {
63			char *fpath = getpath(argv[++i], getrlibpath(), 0);
64			if (fpath == NULL) {
65			fprintf(stderr, "%s: cannot find file '%s'\n",
66			argv[0], argv[i]);
67			quit(1);
68			}
69			fcompile(fpath);
70			} else
71	greg	1.1	goto userror;
72
73			sprintf(stmp, "%s(t)=%s;", XNAME, argv[3]);
74	greg	1.6	scompile(stmp, NULL, 0);
75	greg	1.1	sprintf(stmp, "%s(t)=%s;", YNAME, argv[4]);
76	greg	1.6	scompile(stmp, NULL, 0);
77	greg	1.1	sprintf(stmp, "%s(t)=%s;", ZNAME, argv[5]);
78	greg	1.6	scompile(stmp, NULL, 0);
79	greg	1.1	sprintf(stmp, "%s(t)=%s;", RNAME, argv[6]);
80	greg	1.6	scompile(stmp, NULL, 0);
81	greg	2.11	nseg = eval(argv[7]) + .5;
82	greg	1.1	if (nseg <= 0)
83			goto userror;
84
85	greg	2.8	fputs("# ", stdout);
86			printargs(argc, argv, stdout);
87	greg	1.5	eclock = 0;
88	greg	1.1
89			for (i = 0; i <= nseg; i++) {
90			t = (double)i/nseg;
91			p[0] = funvalue(XNAME, 1, &t);
92			p[1] = funvalue(YNAME, 1, &t);
93			p[2] = funvalue(ZNAME, 1, &t);
94			r = funvalue(RNAME, 1, &t);
95	schorsch	2.5	if (i) {
96	greg	1.1	if (lastr <= r+FTINY && lastr >= r-FTINY) {
97			printf("\n%s cylinder %s.c%d\n",
98			argv[1], argv[2], i);
99			printf("0\n0\n7\n");
100			printf("%18.12g %18.12g %18.12g\n",
101			lastp[0], lastp[1], lastp[2]);
102			printf("%18.12g %18.12g %18.12g\n",
103			p[0], p[1], p[2]);
104			printf("%18.12g\n", r);
105			} else {
106			printf("\n%s cone %s.c%d\n",
107			argv[1], argv[2], i);
108			printf("0\n0\n8\n");
109			f = (lastr - r)/dist2(lastp,p);
110			printf("%18.12g %18.12g %18.12g\n",
111			lastp[0] + flastr(p[0] - lastp[0]),
112			lastp[1] + flastr(p[1] - lastp[1]),
113			lastp[2] + flastr(p[2] - lastp[2]));
114			printf("%18.12g %18.12g %18.12g\n",
115			p[0] + fr(p[0] - lastp[0]),
116			p[1] + fr(p[1] - lastp[1]),
117			p[2] + fr(p[2] - lastp[2]));
118			f = 1.0 - (lastr-r)*f;
119			f = f <= 0.0 ? 0.0 : sqrt(f);
120			printf("%18.12g %18.12g\n", flastr, fr);
121			}
122	schorsch	2.5	}
123	greg	1.1	printf("\n%s sphere %s.s%d\n", argv[1], argv[2], i);
124			printf("0\n0\n4 %18.12g %18.12g %18.12g %18.12g\n",
125			p[0], p[1], p[2], r);
126			VCOPY(lastp, p);
127			lastr = r;
128			}
129	schorsch	2.7	return 0;
130	greg	1.1
131			userror:
132			fprintf(stderr,
133			"Usage: %s material name x(t) y(t) z(t) r(t) nseg [-e expr] [-f file]\n",
134			argv[0]);
135	schorsch	2.7	return 1;
136	greg	1.1	}
137
138
139			double
140	greg	2.6	l_hermite(char *nm)
141	greg	1.1	{
142			double t;
143
144			t = argument(5);
145			return( argument(1)((2.0t-3.0)tt+1.0) +
146			argument(2)(-2.0t+3.0)tt +
147			argument(3)((t-2.0)t+1.0)*t +
148			argument(4)(t-1.0)t*t );
149	greg	1.3	}
150
151
152			double
153	greg	2.6	l_bezier(char *nm)
154	greg	1.3	{
155			double t;
156
157			t = argument(5);
158			return( argument(1) * (1.+t(-3.+t(3.-t))) +
159			argument(2) * 3.t(1.+t*(-2.+t)) +
160			argument(3) * 3.tt*(1.-t) +
161			argument(4) * ttt );
162	greg	1.4	}
163
164
165			double
166	greg	2.6	l_bspline(char *nm)
167	greg	1.4	{
168			double t;
169
170			t = argument(5);
171			return( argument(1) * (1./6.+t(-1./2.+t(1./2.-1./6.*t))) +
172			argument(2) * (2./3.+tt(-1.+1./2.*t)) +
173			argument(3) * (1./6.+t(1./2.+t(1./2.-1./2.*t))) +
174			argument(4) * (1./6.tt*t) );
175	greg	1.1	}