src/gen/genrev.c

#ifndef lint
static char SCCSid[] = "$SunId$ LBL";
#endif

/* Copyright (c) 1989 Regents of the University of California */

/*
 *  genrev.c - program to generate functions of rotation about z
 *
 *      The program takes as input the functions of t for z and r
 *      (the radius).  If z is increasing, the normal points
 *      outward, inward for decreasing z.  Negative radii are forbidden.
 *
 *      8/6/86
 */

#include  <stdio.h>

#define  ZNAME          "Z_"                    /* z function name */
#define  RNAME          "R_"                    /* r function name */

#define  PI             3.14159265358979323846

#define  FTINY          1e-9
                                        /* orientation */
#define  OUT            01
#define  IN             02
#define  UP             04
#define  DOWN           010

double  funvalue(), l_hermite(), l_bezier(), l_bspline(), argument();


main(argc, argv)
int  argc;
char  *argv[];
{
        char  stmp[256];
        char  *modname;
        int  smooth = 0;
        double  t, lastz, z, nextz, lastr, r, nextr;
        double  lastnz, lastnr, nz, nr, nextnz, nextnr;
        int  i, nseg;
        int  orient;

        varset("PI", PI);
        funset("hermite", 5, l_hermite);
        funset("bezier", 5, l_bezier);
        funset("bspline", 5, l_bspline);

        if (argc < 6)
                goto userror;

        for (i = 6; i < argc; i++)
                if (!strcmp(argv[i], "-e"))
                        scompile(NULL, argv[++i]);
                else if (!strcmp(argv[i], "-f"))
                        fcompile(argv[++i]);
                else if (!strcmp(argv[i], "-s"))
                        smooth = 1;
                else
                        goto userror;

        sprintf(stmp, "%s(t)=%s;", ZNAME, argv[3]);
        scompile(NULL, stmp);
        sprintf(stmp, "%s(t)=%s;", RNAME, argv[4]);
        scompile(NULL, stmp);
        nseg = atoi(argv[5]);
        if (nseg <= 0)
                goto userror;
        modname = smooth ? "Phong" : argv[1];

        printhead(argc, argv);

        lastnz = lastnr = 0.0;
        t = 0.0;
        lastz = funvalue(ZNAME, 1, &t);
        lastr = funvalue(RNAME, 1, &t);
        t = 1.0/nseg;
        z = funvalue(ZNAME, 1, &t);
        r = funvalue(RNAME, 1, &t);
        computen(&nz, &nr, lastz, lastr, z, r);
        for (i = 1; i <= nseg; i++) {
                if (i < nseg) {
                        t = (double)(i+1)/nseg;
                        nextz = funvalue(ZNAME, 1, &t);
                        nextr = funvalue(RNAME, 1, &t);
                        computen(&nextnz, &nextnr, z, r, nextz, nextr);
                } else
                        nextnz = nextnr = 0.0;
                orient = 0;
                if (z < lastz-FTINY)
                        orient |= DOWN;
                else if (z > lastz+FTINY)
                        orient |= UP;
                if (r < lastr-FTINY)
                        orient |= IN;
                else if (r > lastr+FTINY)
                        orient |= OUT;
                if (!orient)
                        goto endfor;
                if (smooth) {
                        printf("\n%s texfunc Phong\n", argv[1]);
                        printf("4 rev_dx rev_dy rev_dz rev.cal\n");
                        printf("0\n4\n");
                        if (orient&(UP|DOWN)) {
                                t = (nextnz - lastnz)/(z - lastz);
                                printf("\t%15.9g\t%15.9g\n",
                                                t, lastnz - t*lastz);
                        } else
                                printf("\t0\t%d\n", orient&IN ? 1 : -1);
                        if (orient&(OUT|IN))  {
                                t = (nextnr - lastnr)/(r - lastr);
                                printf("\t%15.9g\t%15.9g\n",
                                                t, lastnr - t*lastr);
                        } else
                                printf("\t0\t%d\n", orient&UP ? 1 : -1);
                }
                if (!(orient&(IN|OUT))) {
                        printf("\n%s %s %s.%d\n", modname,
                                        orient&DOWN ? "tube" : "cylinder",
                                        argv[2], i);
                        printf("0\n0\n7\n");
                        printf("\t0\t0\t%15.9g\n", lastz);
                        printf("\t0\t0\t%15.9g\n", z);
                        printf("\t%15.9g\n", r);
                } else if (!(orient&(UP|DOWN))) {
                        printf("\n%s ring %s.%d\n", modname, argv[2], i);
                        printf("0\n0\n8\n");
                        printf("\t0\t0\t%15.9g\n", z);
                        printf("\t0\t0\t%15.9g\n", orient&IN ? 1.0 : -1.0);
                        printf("\t%15.9g\t%15.9g\n", lastr, r);
                } else {
                        printf("\n%s %s %s.%d\n", modname,
                                        orient&DOWN ? "cup" : "cone",
                                        argv[2], i);
                        printf("0\n0\n8\n");
                        printf("\t0\t0\t%15.9g\n", lastz);
                        printf("\t0\t0\t%15.9g\n", z);
                        printf("\t%15.9g\t%15.9g\n", lastr, r);
                }
        endfor:
                lastz = z; lastr = r;
                z = nextz; r = nextr;
                lastnz = nz; lastnr = nr;
                nz = nextnz; nr = nextnr;
        }
        quit(0);

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


computen(nzp, nrp, z0, r0, z1, r1)              /* compute normal */
double  *nzp, *nrp, z0, r0, z1, r1;
{
        extern double  sqrt();
        double  dr, dz, len;

        dz = r0 - r1;                           /* right angle vector */
        dr = z1 - z0;
        len = sqrt(dr*dr + dz*dz);
        *nzp = dz/len;
        *nrp = dr/len;
}


eputs(msg)
char  *msg;
{
        fputs(msg, stderr);
}


wputs(msg)
char  *msg;
{
        eputs(msg);
}


quit(code)
{
        exit(code);
}


printhead(ac, av)               /* print command header */
register int  ac;
register char  **av;
{
        putchar('#');
        while (ac--) {
                putchar(' ');
                fputs(*av++, stdout);
        }
        putchar('\n');
}


double
l_hermite()                     
{
        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()
{
        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()
{
        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:	1.5
Committed:	Wed Mar 7 11:14:40 1990 UTC (34 years, 1 month ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.4:	+17 -3 lines
Log Message:	added bezier and bspline functions
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2			static char SCCSid[] = "$SunId$ LBL";
3			#endif
4	greg	1.2
5	greg	1.5	/* Copyright (c) 1989 Regents of the University of California */
6
7	greg	1.2	/*
8	greg	1.1	* genrev.c - program to generate functions of rotation about z
9			*
10			* The program takes as input the functions of t for z and r
11			* (the radius). If z is increasing, the normal points
12			* outward, inward for decreasing z. Negative radii are forbidden.
13			*
14			* 8/6/86
15			*/
16
17			#include <stdio.h>
18
19			#define ZNAME "Z_" /* z function name */
20			#define RNAME "R_" /* r function name */
21
22			#define PI 3.14159265358979323846
23
24			#define FTINY 1e-9
25			/* orientation */
26			#define OUT 01
27			#define IN 02
28			#define UP 04
29			#define DOWN 010
30
31	greg	1.5	double funvalue(), l_hermite(), l_bezier(), l_bspline(), argument();
32	greg	1.1
33
34			main(argc, argv)
35			int argc;
36			char *argv[];
37			{
38			char stmp[256];
39			char *modname;
40			int smooth = 0;
41			double t, lastz, z, nextz, lastr, r, nextr;
42			double lastnz, lastnr, nz, nr, nextnz, nextnr;
43			int i, nseg;
44			int orient;
45
46			varset("PI", PI);
47			funset("hermite", 5, l_hermite);
48	greg	1.4	funset("bezier", 5, l_bezier);
49	greg	1.5	funset("bspline", 5, l_bspline);
50	greg	1.1
51			if (argc < 6)
52			goto userror;
53
54			for (i = 6; i < argc; i++)
55			if (!strcmp(argv[i], "-e"))
56			scompile(NULL, argv[++i]);
57			else if (!strcmp(argv[i], "-f"))
58			fcompile(argv[++i]);
59			else if (!strcmp(argv[i], "-s"))
60			smooth = 1;
61			else
62			goto userror;
63
64			sprintf(stmp, "%s(t)=%s;", ZNAME, argv[3]);
65			scompile(NULL, stmp);
66			sprintf(stmp, "%s(t)=%s;", RNAME, argv[4]);
67			scompile(NULL, stmp);
68			nseg = atoi(argv[5]);
69			if (nseg <= 0)
70			goto userror;
71	greg	1.3	modname = smooth ? "Phong" : argv[1];
72	greg	1.1
73			printhead(argc, argv);
74
75			lastnz = lastnr = 0.0;
76			t = 0.0;
77			lastz = funvalue(ZNAME, 1, &t);
78			lastr = funvalue(RNAME, 1, &t);
79			t = 1.0/nseg;
80			z = funvalue(ZNAME, 1, &t);
81			r = funvalue(RNAME, 1, &t);
82			computen(&nz, &nr, lastz, lastr, z, r);
83			for (i = 1; i <= nseg; i++) {
84			if (i < nseg) {
85			t = (double)(i+1)/nseg;
86			nextz = funvalue(ZNAME, 1, &t);
87			nextr = funvalue(RNAME, 1, &t);
88			computen(&nextnz, &nextnr, z, r, nextz, nextr);
89			} else
90			nextnz = nextnr = 0.0;
91			orient = 0;
92			if (z < lastz-FTINY)
93			orient \|= DOWN;
94			else if (z > lastz+FTINY)
95			orient \|= UP;
96			if (r < lastr-FTINY)
97			orient \|= IN;
98			else if (r > lastr+FTINY)
99			orient \|= OUT;
100			if (!orient)
101			goto endfor;
102			if (smooth) {
103	greg	1.3	printf("\n%s texfunc Phong\n", argv[1]);
104	greg	1.1	printf("4 rev_dx rev_dy rev_dz rev.cal\n");
105			printf("0\n4\n");
106			if (orient&(UP\|DOWN)) {
107			t = (nextnz - lastnz)/(z - lastz);
108			printf("\t%15.9g\t%15.9g\n",
109			t, lastnz - t*lastz);
110			} else
111			printf("\t0\t%d\n", orient&IN ? 1 : -1);
112			if (orient&(OUT\|IN)) {
113			t = (nextnr - lastnr)/(r - lastr);
114			printf("\t%15.9g\t%15.9g\n",
115			t, lastnr - t*lastr);
116			} else
117			printf("\t0\t%d\n", orient&UP ? 1 : -1);
118			}
119			if (!(orient&(IN\|OUT))) {
120			printf("\n%s %s %s.%d\n", modname,
121			orient&DOWN ? "tube" : "cylinder",
122			argv[2], i);
123			printf("0\n0\n7\n");
124			printf("\t0\t0\t%15.9g\n", lastz);
125			printf("\t0\t0\t%15.9g\n", z);
126			printf("\t%15.9g\n", r);
127			} else if (!(orient&(UP\|DOWN))) {
128			printf("\n%s ring %s.%d\n", modname, argv[2], i);
129			printf("0\n0\n8\n");
130			printf("\t0\t0\t%15.9g\n", z);
131			printf("\t0\t0\t%15.9g\n", orient&IN ? 1.0 : -1.0);
132			printf("\t%15.9g\t%15.9g\n", lastr, r);
133			} else {
134			printf("\n%s %s %s.%d\n", modname,
135			orient&DOWN ? "cup" : "cone",
136			argv[2], i);
137			printf("0\n0\n8\n");
138			printf("\t0\t0\t%15.9g\n", lastz);
139			printf("\t0\t0\t%15.9g\n", z);
140			printf("\t%15.9g\t%15.9g\n", lastr, r);
141			}
142			endfor:
143			lastz = z; lastr = r;
144			z = nextz; r = nextr;
145			lastnz = nz; lastnr = nr;
146			nz = nextnz; nr = nextnr;
147			}
148			quit(0);
149
150			userror:
151			fprintf(stderr,
152			"Usage: %s material name z(t) r(t) nseg [-e expr] [-f file] [-s]\n",
153			argv[0]);
154			quit(1);
155			}
156
157
158			computen(nzp, nrp, z0, r0, z1, r1) /* compute normal */
159			double nzp, nrp, z0, r0, z1, r1;
160			{
161			extern double sqrt();
162			double dr, dz, len;
163
164			dz = r0 - r1; /* right angle vector */
165			dr = z1 - z0;
166			len = sqrt(drdr + dzdz);
167			*nzp = dz/len;
168			*nrp = dr/len;
169			}
170
171
172			eputs(msg)
173			char *msg;
174			{
175			fputs(msg, stderr);
176			}
177
178
179			wputs(msg)
180			char *msg;
181			{
182			eputs(msg);
183			}
184
185
186			quit(code)
187			{
188			exit(code);
189			}
190
191
192			printhead(ac, av) /* print command header */
193			register int ac;
194			register char **av;
195			{
196			putchar('#');
197			while (ac--) {
198			putchar(' ');
199			fputs(*av++, stdout);
200			}
201			putchar('\n');
202			}
203
204
205			double
206			l_hermite()
207			{
208			double t;
209
210			t = argument(5);
211			return( argument(1)((2.0t-3.0)tt+1.0) +
212			argument(2)(-2.0t+3.0)tt +
213			argument(3)((t-2.0)t+1.0)*t +
214			argument(4)(t-1.0)t*t );
215	greg	1.4	}
216
217
218			double
219			l_bezier()
220			{
221			double t;
222
223			t = argument(5);
224			return( argument(1) * (1.+t(-3.+t(3.-t))) +
225			argument(2) * 3.t(1.+t*(-2.+t)) +
226			argument(3) * 3.tt*(1.-t) +
227			argument(4) * ttt );
228	greg	1.5	}
229
230
231			double
232			l_bspline()
233			{
234			double t;
235
236			t = argument(5);
237			return( argument(1) * (1./6.+t(-1./2.+t(1./2.-1./6.*t))) +
238			argument(2) * (2./3.+tt(-1.+1./2.*t)) +
239			argument(3) * (1./6.+t(1./2.+t(1./2.-1./2.*t))) +
240			argument(4) * (1./6.tt*t) );
241	greg	1.1	}