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/* Copyright (c) 1989 Regents of the University of California */ |
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|
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#ifndef lint |
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static char SCCSid[] = "$SunId$ LBL"; |
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#endif |
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|
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/* |
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* genrev.c - program to generate functions of rotation about z |
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* |
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* The program takes as input the functions of t for z and r |
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* (the radius). If z is increasing, the normal points |
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* outward, inward for decreasing z. Negative radii are forbidden. |
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* |
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* 8/6/86 |
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*/ |
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|
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#include <stdio.h> |
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|
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#define ZNAME "Z_" /* z function name */ |
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#define RNAME "R_" /* r function name */ |
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|
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#define PI 3.14159265358979323846 |
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|
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#define FTINY 1e-9 |
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/* orientation */ |
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#define OUT 01 |
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#define IN 02 |
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#define UP 04 |
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#define DOWN 010 |
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|
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double funvalue(), l_hermite(), l_bezier(), argument(); |
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|
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|
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main(argc, argv) |
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int argc; |
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char *argv[]; |
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{ |
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char stmp[256]; |
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char *modname; |
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int smooth = 0; |
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double t, lastz, z, nextz, lastr, r, nextr; |
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double lastnz, lastnr, nz, nr, nextnz, nextnr; |
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int i, nseg; |
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int orient; |
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|
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varset("PI", PI); |
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funset("hermite", 5, l_hermite); |
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funset("bezier", 5, l_bezier); |
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|
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if (argc < 6) |
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goto userror; |
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|
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for (i = 6; i < argc; i++) |
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if (!strcmp(argv[i], "-e")) |
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scompile(NULL, argv[++i]); |
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else if (!strcmp(argv[i], "-f")) |
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fcompile(argv[++i]); |
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else if (!strcmp(argv[i], "-s")) |
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smooth = 1; |
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else |
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goto userror; |
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|
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sprintf(stmp, "%s(t)=%s;", ZNAME, argv[3]); |
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scompile(NULL, stmp); |
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sprintf(stmp, "%s(t)=%s;", RNAME, argv[4]); |
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scompile(NULL, stmp); |
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nseg = atoi(argv[5]); |
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if (nseg <= 0) |
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goto userror; |
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modname = smooth ? "Phong" : argv[1]; |
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|
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printhead(argc, argv); |
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|
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lastnz = lastnr = 0.0; |
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t = 0.0; |
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lastz = funvalue(ZNAME, 1, &t); |
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lastr = funvalue(RNAME, 1, &t); |
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t = 1.0/nseg; |
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z = funvalue(ZNAME, 1, &t); |
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r = funvalue(RNAME, 1, &t); |
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computen(&nz, &nr, lastz, lastr, z, r); |
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for (i = 1; i <= nseg; i++) { |
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if (i < nseg) { |
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t = (double)(i+1)/nseg; |
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nextz = funvalue(ZNAME, 1, &t); |
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nextr = funvalue(RNAME, 1, &t); |
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computen(&nextnz, &nextnr, z, r, nextz, nextr); |
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} else |
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nextnz = nextnr = 0.0; |
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orient = 0; |
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if (z < lastz-FTINY) |
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orient |= DOWN; |
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else if (z > lastz+FTINY) |
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orient |= UP; |
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if (r < lastr-FTINY) |
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orient |= IN; |
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else if (r > lastr+FTINY) |
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orient |= OUT; |
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if (!orient) |
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goto endfor; |
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if (smooth) { |
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printf("\n%s texfunc Phong\n", argv[1]); |
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printf("4 rev_dx rev_dy rev_dz rev.cal\n"); |
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printf("0\n4\n"); |
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if (orient&(UP|DOWN)) { |
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t = (nextnz - lastnz)/(z - lastz); |
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printf("\t%15.9g\t%15.9g\n", |
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t, lastnz - t*lastz); |
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} else |
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printf("\t0\t%d\n", orient&IN ? 1 : -1); |
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if (orient&(OUT|IN)) { |
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t = (nextnr - lastnr)/(r - lastr); |
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printf("\t%15.9g\t%15.9g\n", |
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t, lastnr - t*lastr); |
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} else |
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printf("\t0\t%d\n", orient&UP ? 1 : -1); |
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} |
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if (!(orient&(IN|OUT))) { |
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printf("\n%s %s %s.%d\n", modname, |
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orient&DOWN ? "tube" : "cylinder", |
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argv[2], i); |
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printf("0\n0\n7\n"); |
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printf("\t0\t0\t%15.9g\n", lastz); |
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printf("\t0\t0\t%15.9g\n", z); |
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printf("\t%15.9g\n", r); |
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} else if (!(orient&(UP|DOWN))) { |
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printf("\n%s ring %s.%d\n", modname, argv[2], i); |
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printf("0\n0\n8\n"); |
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printf("\t0\t0\t%15.9g\n", z); |
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printf("\t0\t0\t%15.9g\n", orient&IN ? 1.0 : -1.0); |
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printf("\t%15.9g\t%15.9g\n", lastr, r); |
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} else { |
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printf("\n%s %s %s.%d\n", modname, |
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orient&DOWN ? "cup" : "cone", |
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argv[2], i); |
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printf("0\n0\n8\n"); |
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printf("\t0\t0\t%15.9g\n", lastz); |
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printf("\t0\t0\t%15.9g\n", z); |
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printf("\t%15.9g\t%15.9g\n", lastr, r); |
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} |
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endfor: |
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lastz = z; lastr = r; |
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z = nextz; r = nextr; |
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lastnz = nz; lastnr = nr; |
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nz = nextnz; nr = nextnr; |
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} |
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quit(0); |
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|
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userror: |
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fprintf(stderr, |
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"Usage: %s material name z(t) r(t) nseg [-e expr] [-f file] [-s]\n", |
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argv[0]); |
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quit(1); |
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} |
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|
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|
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computen(nzp, nrp, z0, r0, z1, r1) /* compute normal */ |
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double *nzp, *nrp, z0, r0, z1, r1; |
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{ |
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extern double sqrt(); |
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double dr, dz, len; |
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|
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dz = r0 - r1; /* right angle vector */ |
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dr = z1 - z0; |
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len = sqrt(dr*dr + dz*dz); |
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*nzp = dz/len; |
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*nrp = dr/len; |
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} |
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|
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|
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eputs(msg) |
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char *msg; |
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{ |
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fputs(msg, stderr); |
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} |
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|
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|
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wputs(msg) |
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char *msg; |
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{ |
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eputs(msg); |
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} |
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|
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|
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quit(code) |
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{ |
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exit(code); |
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} |
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|
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|
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printhead(ac, av) /* print command header */ |
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register int ac; |
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register char **av; |
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{ |
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putchar('#'); |
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while (ac--) { |
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putchar(' '); |
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fputs(*av++, stdout); |
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} |
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putchar('\n'); |
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} |
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|
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|
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double |
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l_hermite() |
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{ |
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double t; |
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|
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t = argument(5); |
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return( argument(1)*((2.0*t-3.0)*t*t+1.0) + |
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argument(2)*(-2.0*t+3.0)*t*t + |
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argument(3)*((t-2.0)*t+1.0)*t + |
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argument(4)*(t-1.0)*t*t ); |
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} |
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|
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|
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double |
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l_bezier() |
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{ |
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double t; |
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|
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t = argument(5); |
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return( argument(1) * (1.+t*(-3.+t*(3.-t))) + |
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argument(2) * 3.*t*(1.+t*(-2.+t)) + |
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argument(3) * 3.*t*t*(1.-t) + |
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argument(4) * t*t*t ); |
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} |
