| 1 |
#ifndef lint |
| 2 |
static const char RCSid[] = "$Id: xf.c,v 1.14 2003/02/28 20:11:30 greg Exp $"; |
| 3 |
#endif |
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/* |
| 5 |
* Routines for 4x4 homogeneous, rigid-body transformations |
| 6 |
*/ |
| 7 |
|
| 8 |
#include <stdio.h> |
| 9 |
#include <math.h> |
| 10 |
#include <stdlib.h> |
| 11 |
#include <string.h> |
| 12 |
#include "parser.h" |
| 13 |
|
| 14 |
#define d2r(a) ((PI/180.)*(a)) |
| 15 |
|
| 16 |
#define checkarg(a,l) if (av[i][a] || badarg(ac-i-1,av+i+1,l)) goto done |
| 17 |
|
| 18 |
MAT4 m4ident = MAT4IDENT; |
| 19 |
|
| 20 |
static MAT4 m4tmp; /* for efficiency */ |
| 21 |
|
| 22 |
XF_SPEC *xf_context = NULL; /* current context */ |
| 23 |
char **xf_argend; /* end of transform argument list */ |
| 24 |
static char **xf_argbeg; /* beginning of transform argument list */ |
| 25 |
|
| 26 |
|
| 27 |
int |
| 28 |
xf_handler(ac, av) /* handle xf entity */ |
| 29 |
int ac; |
| 30 |
char **av; |
| 31 |
{ |
| 32 |
register XF_SPEC *spec; |
| 33 |
register int n; |
| 34 |
int rv; |
| 35 |
|
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if (ac == 1) { /* something with existing transform */ |
| 37 |
if ((spec = xf_context) == NULL) |
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return(MG_ECNTXT); |
| 39 |
n = -1; |
| 40 |
if (spec->xarr != NULL) { /* check for iteration */ |
| 41 |
register struct xf_array *ap = spec->xarr; |
| 42 |
|
| 43 |
(void)xf_aname((struct xf_array *)NULL); |
| 44 |
n = ap->ndim; |
| 45 |
while (n--) { |
| 46 |
if (++ap->aarg[n].i < ap->aarg[n].n) |
| 47 |
break; |
| 48 |
(void)strcpy(ap->aarg[n].arg, "0"); |
| 49 |
ap->aarg[n].i = 0; |
| 50 |
} |
| 51 |
if (n >= 0) { |
| 52 |
if ((rv = mg_fgoto(&ap->spos)) != MG_OK) |
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return(rv); |
| 54 |
sprintf(ap->aarg[n].arg, "%d", ap->aarg[n].i); |
| 55 |
(void)xf_aname(ap); |
| 56 |
} |
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} |
| 58 |
if (n < 0) { /* pop transform */ |
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xf_context = spec->prev; |
| 60 |
free_xf(spec); |
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return(MG_OK); |
| 62 |
} |
| 63 |
} else { /* else allocate transform */ |
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if ((spec = new_xf(ac-1, av+1)) == NULL) |
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return(MG_EMEM); |
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if (spec->xarr != NULL) |
| 67 |
(void)xf_aname(spec->xarr); |
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spec->prev = xf_context; /* push onto stack */ |
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xf_context = spec; |
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} |
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/* translate new specification */ |
| 72 |
n = xf_ac(spec); |
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n -= xf_ac(spec->prev); /* incremental comp. is more eff. */ |
| 74 |
if (xf(&spec->xf, n, xf_av(spec)) != n) |
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return(MG_ETYPE); |
| 76 |
/* check for vertex reversal */ |
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if ((spec->rev = (spec->xf.sca < 0.))) |
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spec->xf.sca = -spec->xf.sca; |
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/* compute total transformation */ |
| 80 |
if (spec->prev != NULL) { |
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multmat4(spec->xf.xfm, spec->xf.xfm, spec->prev->xf.xfm); |
| 82 |
spec->xf.sca *= spec->prev->xf.sca; |
| 83 |
spec->rev ^= spec->prev->rev; |
| 84 |
} |
| 85 |
spec->xid = comp_xfid(spec->xf.xfm); /* compute unique ID */ |
| 86 |
return(MG_OK); |
| 87 |
} |
| 88 |
|
| 89 |
|
| 90 |
XF_SPEC * |
| 91 |
new_xf(ac, av) /* allocate new transform structure */ |
| 92 |
int ac; |
| 93 |
char **av; |
| 94 |
{ |
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register XF_SPEC *spec; |
| 96 |
register int i; |
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char *cp; |
| 98 |
int n, ndim; |
| 99 |
|
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ndim = 0; |
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n = 0; /* compute space req'd by arguments */ |
| 102 |
for (i = 0; i < ac; i++) |
| 103 |
if (!strcmp(av[i], "-a")) { |
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ndim++; |
| 105 |
i++; |
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} else |
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n += strlen(av[i]) + 1; |
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if (ndim > XF_MAXDIM) |
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return(NULL); |
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spec = (XF_SPEC *)malloc(sizeof(XF_SPEC) + n); |
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if (spec == NULL) |
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return(NULL); |
| 113 |
if (ndim) { |
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spec->xarr = (struct xf_array *)malloc(sizeof(struct xf_array)); |
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if (spec->xarr == NULL) |
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return(NULL); |
| 117 |
mg_fgetpos(&spec->xarr->spos); |
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spec->xarr->ndim = 0; /* incremented below */ |
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} else |
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spec->xarr = NULL; |
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spec->xac = ac + xf_argc; |
| 122 |
/* and store new xf arguments */ |
| 123 |
if (xf_argbeg == NULL || xf_av(spec) < xf_argbeg) { |
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register char **newav = |
| 125 |
(char **)malloc((spec->xac+1)*sizeof(char *)); |
| 126 |
if (newav == NULL) |
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return(NULL); |
| 128 |
for (i = xf_argc; i-- > 0; ) |
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newav[ac+i] = xf_argend[i-xf_context->xac]; |
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*(xf_argend = newav + spec->xac) = NULL; |
| 131 |
if (xf_argbeg != NULL) |
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free(xf_argbeg); |
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xf_argbeg = newav; |
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} |
| 135 |
cp = (char *)(spec + 1); /* use memory allocated above */ |
| 136 |
for (i = 0; i < ac; i++) |
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if (!strcmp(av[i], "-a")) { |
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xf_av(spec)[i++] = "-i"; |
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xf_av(spec)[i] = strcpy( |
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spec->xarr->aarg[spec->xarr->ndim].arg, |
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"0"); |
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spec->xarr->aarg[spec->xarr->ndim].i = 0; |
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spec->xarr->aarg[spec->xarr->ndim++].n = atoi(av[i]); |
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} else { |
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xf_av(spec)[i] = strcpy(cp, av[i]); |
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cp += strlen(av[i]) + 1; |
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} |
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return(spec); |
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} |
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|
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|
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void |
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free_xf(spec) /* free a transform */ |
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register XF_SPEC *spec; |
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{ |
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if (spec->xarr != NULL) |
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free(spec->xarr); |
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free(spec); |
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} |
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|
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|
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int |
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xf_aname(ap) /* put out name for this instance */ |
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register struct xf_array *ap; |
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{ |
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static char oname[10*XF_MAXDIM]; |
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static char *oav[3] = {mg_ename[MG_E_OBJECT], oname}; |
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register int i; |
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register char *cp1, *cp2; |
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|
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if (ap == NULL) |
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return(mg_handle(MG_E_OBJECT, 1, oav)); |
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cp1 = oname; |
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*cp1 = 'a'; |
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for (i = 0; i < ap->ndim; i++) { |
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for (cp2 = ap->aarg[i].arg; *cp2; ) |
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*++cp1 = *cp2++; |
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*++cp1 = '.'; |
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} |
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*cp1 = '\0'; |
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return(mg_handle(MG_E_OBJECT, 2, oav)); |
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} |
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|
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|
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long |
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comp_xfid(xfm) /* compute unique ID from matrix */ |
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register MAT4 xfm; |
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{ |
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static char shifttab[64] = { 15, 5, 11, 5, 6, 3, |
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9, 15, 13, 2, 13, 5, 2, 12, 14, 11, |
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11, 12, 12, 3, 2, 11, 8, 12, 1, 12, |
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5, 4, 15, 9, 14, 5, 13, 14, 2, 10, |
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10, 14, 12, 3, 5, 5, 14, 6, 12, 11, |
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13, 9, 12, 8, 1, 6, 5, 12, 7, 13, |
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15, 8, 9, 2, 6, 11, 9, 11 }; |
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register int i; |
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register long xid; |
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|
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xid = 0; /* compute unique transform id */ |
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for (i = 0; i < sizeof(MAT4)/sizeof(unsigned short); i++) |
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xid ^= (long)(((unsigned short *)xfm)[i]) << shifttab[i&63]; |
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return(xid); |
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} |
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|
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|
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void |
| 207 |
xf_clear() /* clear transform stack */ |
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{ |
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register XF_SPEC *spec; |
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|
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if (xf_argbeg != NULL) { |
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free(xf_argbeg); |
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xf_argbeg = xf_argend = NULL; |
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} |
| 215 |
while ((spec = xf_context) != NULL) { |
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xf_context = spec->prev; |
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free_xf(spec); |
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} |
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} |
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|
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|
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void |
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xf_xfmpoint(v1, v2) /* transform a point by the current matrix */ |
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FVECT v1, v2; |
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{ |
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if (xf_context == NULL) { |
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VCOPY(v1, v2); |
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return; |
| 229 |
} |
| 230 |
multp3(v1, v2, xf_context->xf.xfm); |
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} |
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|
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|
| 234 |
void |
| 235 |
xf_xfmvect(v1, v2) /* transform a vector using current matrix */ |
| 236 |
FVECT v1, v2; |
| 237 |
{ |
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if (xf_context == NULL) { |
| 239 |
VCOPY(v1, v2); |
| 240 |
return; |
| 241 |
} |
| 242 |
multv3(v1, v2, xf_context->xf.xfm); |
| 243 |
} |
| 244 |
|
| 245 |
|
| 246 |
void |
| 247 |
xf_rotvect(v1, v2) /* rotate a vector using current matrix */ |
| 248 |
FVECT v1, v2; |
| 249 |
{ |
| 250 |
xf_xfmvect(v1, v2); |
| 251 |
if (xf_context == NULL) |
| 252 |
return; |
| 253 |
v1[0] /= xf_context->xf.sca; |
| 254 |
v1[1] /= xf_context->xf.sca; |
| 255 |
v1[2] /= xf_context->xf.sca; |
| 256 |
} |
| 257 |
|
| 258 |
|
| 259 |
double |
| 260 |
xf_scale(d) /* scale a number by the current transform */ |
| 261 |
double d; |
| 262 |
{ |
| 263 |
if (xf_context == NULL) |
| 264 |
return(d); |
| 265 |
return(d*xf_context->xf.sca); |
| 266 |
} |
| 267 |
|
| 268 |
|
| 269 |
void |
| 270 |
multmat4(m4a, m4b, m4c) /* multiply m4b X m4c and put into m4a */ |
| 271 |
MAT4 m4a; |
| 272 |
register MAT4 m4b, m4c; |
| 273 |
{ |
| 274 |
register int i, j; |
| 275 |
|
| 276 |
for (i = 4; i--; ) |
| 277 |
for (j = 4; j--; ) |
| 278 |
m4tmp[i][j] = m4b[i][0]*m4c[0][j] + |
| 279 |
m4b[i][1]*m4c[1][j] + |
| 280 |
m4b[i][2]*m4c[2][j] + |
| 281 |
m4b[i][3]*m4c[3][j]; |
| 282 |
|
| 283 |
copymat4(m4a, m4tmp); |
| 284 |
} |
| 285 |
|
| 286 |
|
| 287 |
void |
| 288 |
multv3(v3a, v3b, m4) /* transform vector v3b by m4 and put into v3a */ |
| 289 |
FVECT v3a; |
| 290 |
register FVECT v3b; |
| 291 |
register MAT4 m4; |
| 292 |
{ |
| 293 |
m4tmp[0][0] = v3b[0]*m4[0][0] + v3b[1]*m4[1][0] + v3b[2]*m4[2][0]; |
| 294 |
m4tmp[0][1] = v3b[0]*m4[0][1] + v3b[1]*m4[1][1] + v3b[2]*m4[2][1]; |
| 295 |
m4tmp[0][2] = v3b[0]*m4[0][2] + v3b[1]*m4[1][2] + v3b[2]*m4[2][2]; |
| 296 |
|
| 297 |
v3a[0] = m4tmp[0][0]; |
| 298 |
v3a[1] = m4tmp[0][1]; |
| 299 |
v3a[2] = m4tmp[0][2]; |
| 300 |
} |
| 301 |
|
| 302 |
|
| 303 |
void |
| 304 |
multp3(p3a, p3b, m4) /* transform p3b by m4 and put into p3a */ |
| 305 |
register FVECT p3a; |
| 306 |
FVECT p3b; |
| 307 |
register MAT4 m4; |
| 308 |
{ |
| 309 |
multv3(p3a, p3b, m4); /* transform as vector */ |
| 310 |
p3a[0] += m4[3][0]; /* translate */ |
| 311 |
p3a[1] += m4[3][1]; |
| 312 |
p3a[2] += m4[3][2]; |
| 313 |
} |
| 314 |
|
| 315 |
|
| 316 |
int |
| 317 |
xf(ret, ac, av) /* get transform specification */ |
| 318 |
register XF *ret; |
| 319 |
int ac; |
| 320 |
char **av; |
| 321 |
{ |
| 322 |
MAT4 xfmat, m4; |
| 323 |
double xfsca, dtmp; |
| 324 |
int i, icnt; |
| 325 |
|
| 326 |
setident4(ret->xfm); |
| 327 |
ret->sca = 1.0; |
| 328 |
|
| 329 |
icnt = 1; |
| 330 |
setident4(xfmat); |
| 331 |
xfsca = 1.0; |
| 332 |
|
| 333 |
for (i = 0; i < ac && av[i][0] == '-'; i++) { |
| 334 |
|
| 335 |
setident4(m4); |
| 336 |
|
| 337 |
switch (av[i][1]) { |
| 338 |
|
| 339 |
case 't': /* translate */ |
| 340 |
checkarg(2,"fff"); |
| 341 |
m4[3][0] = atof(av[++i]); |
| 342 |
m4[3][1] = atof(av[++i]); |
| 343 |
m4[3][2] = atof(av[++i]); |
| 344 |
break; |
| 345 |
|
| 346 |
case 'r': /* rotate */ |
| 347 |
switch (av[i][2]) { |
| 348 |
case 'x': |
| 349 |
checkarg(3,"f"); |
| 350 |
dtmp = d2r(atof(av[++i])); |
| 351 |
m4[1][1] = m4[2][2] = cos(dtmp); |
| 352 |
m4[2][1] = -(m4[1][2] = sin(dtmp)); |
| 353 |
break; |
| 354 |
case 'y': |
| 355 |
checkarg(3,"f"); |
| 356 |
dtmp = d2r(atof(av[++i])); |
| 357 |
m4[0][0] = m4[2][2] = cos(dtmp); |
| 358 |
m4[0][2] = -(m4[2][0] = sin(dtmp)); |
| 359 |
break; |
| 360 |
case 'z': |
| 361 |
checkarg(3,"f"); |
| 362 |
dtmp = d2r(atof(av[++i])); |
| 363 |
m4[0][0] = m4[1][1] = cos(dtmp); |
| 364 |
m4[1][0] = -(m4[0][1] = sin(dtmp)); |
| 365 |
break; |
| 366 |
default: |
| 367 |
goto done; |
| 368 |
} |
| 369 |
break; |
| 370 |
|
| 371 |
case 's': /* scale */ |
| 372 |
checkarg(2,"f"); |
| 373 |
dtmp = atof(av[i+1]); |
| 374 |
if (dtmp == 0.0) goto done; |
| 375 |
i++; |
| 376 |
xfsca *= |
| 377 |
m4[0][0] = |
| 378 |
m4[1][1] = |
| 379 |
m4[2][2] = dtmp; |
| 380 |
break; |
| 381 |
|
| 382 |
case 'm': /* mirror */ |
| 383 |
switch (av[i][2]) { |
| 384 |
case 'x': |
| 385 |
checkarg(3,""); |
| 386 |
xfsca *= |
| 387 |
m4[0][0] = -1.0; |
| 388 |
break; |
| 389 |
case 'y': |
| 390 |
checkarg(3,""); |
| 391 |
xfsca *= |
| 392 |
m4[1][1] = -1.0; |
| 393 |
break; |
| 394 |
case 'z': |
| 395 |
checkarg(3,""); |
| 396 |
xfsca *= |
| 397 |
m4[2][2] = -1.0; |
| 398 |
break; |
| 399 |
default: |
| 400 |
goto done; |
| 401 |
} |
| 402 |
break; |
| 403 |
|
| 404 |
case 'i': /* iterate */ |
| 405 |
checkarg(2,"i"); |
| 406 |
while (icnt-- > 0) { |
| 407 |
multmat4(ret->xfm, ret->xfm, xfmat); |
| 408 |
ret->sca *= xfsca; |
| 409 |
} |
| 410 |
icnt = atoi(av[++i]); |
| 411 |
setident4(xfmat); |
| 412 |
xfsca = 1.0; |
| 413 |
continue; |
| 414 |
|
| 415 |
default: |
| 416 |
goto done; |
| 417 |
|
| 418 |
} |
| 419 |
multmat4(xfmat, xfmat, m4); |
| 420 |
} |
| 421 |
done: |
| 422 |
while (icnt-- > 0) { |
| 423 |
multmat4(ret->xfm, ret->xfm, xfmat); |
| 424 |
ret->sca *= xfsca; |
| 425 |
} |
| 426 |
return(i); |
| 427 |
} |
