| 1 |
/* Copyright (c) 1991 Regents of the University of California */ |
| 2 |
|
| 3 |
#ifndef lint |
| 4 |
static char SCCSid[] = "$SunId$ LBL"; |
| 5 |
#endif |
| 6 |
|
| 7 |
/* |
| 8 |
* Routines for light-redirecting materials and |
| 9 |
* their associated virtual light sources |
| 10 |
*/ |
| 11 |
|
| 12 |
#include "ray.h" |
| 13 |
|
| 14 |
#include "otypes.h" |
| 15 |
|
| 16 |
#include "source.h" |
| 17 |
|
| 18 |
/* |
| 19 |
* The arguments for MAT_DIRECT1 are: |
| 20 |
* |
| 21 |
* 5+ coef1 dx1 dy1 dz1 funcfile transform.. |
| 22 |
* 0 |
| 23 |
* n A1 A2 .. An |
| 24 |
* |
| 25 |
* The arguments for MAT_DIRECT2 are: |
| 26 |
* |
| 27 |
* 9+ coef1 dx1 dy1 dz1 coef2 dx2 dy2 dz2 funcfile transform.. |
| 28 |
* 0 |
| 29 |
* n A1 A2 .. An |
| 30 |
*/ |
| 31 |
|
| 32 |
|
| 33 |
extern double varvalue(); |
| 34 |
|
| 35 |
int dir_proj(); |
| 36 |
VSMATERIAL direct1_vs = {dir_proj, 1}; |
| 37 |
VSMATERIAL direct2_vs = {dir_proj, 2}; |
| 38 |
|
| 39 |
#define fndx(m) ((m)->otype == MAT_DIRECT1 ? 4 : 8) |
| 40 |
|
| 41 |
|
| 42 |
static |
| 43 |
dir_check(m) /* check arguments and load function file */ |
| 44 |
register OBJREC *m; |
| 45 |
{ |
| 46 |
register FULLXF *mxf; |
| 47 |
register int ff; |
| 48 |
|
| 49 |
ff = fndx(m)+1; |
| 50 |
if (ff > m->oargs.nsargs) |
| 51 |
objerror(m, USER, "too few arguments"); |
| 52 |
if (m->os == NULL) { |
| 53 |
mxf = (FULLXF *)malloc(sizeof(FULLXF)); |
| 54 |
if (mxf == NULL) |
| 55 |
error(SYSTEM, "out of memory in dir_check"); |
| 56 |
if (fullxf(mxf, m->oargs.nsargs-ff, m->oargs.sarg+ff) != |
| 57 |
m->oargs.nsargs-ff) |
| 58 |
objerror(m, USER, "bad transform"); |
| 59 |
if (mxf->f.sca < 0.0) |
| 60 |
mxf->f.sca = -mxf->f.sca; |
| 61 |
if (mxf->b.sca < 0.0) |
| 62 |
mxf->b.sca = -mxf->b.sca; |
| 63 |
m->os = (char *)mxf; |
| 64 |
} |
| 65 |
} |
| 66 |
|
| 67 |
|
| 68 |
m_direct(m, r) /* shade redirected ray */ |
| 69 |
register OBJREC *m; |
| 70 |
register RAY *r; |
| 71 |
{ |
| 72 |
/* check if source ray */ |
| 73 |
if (r->rsrc >= 0 && source[r->rsrc].so != r->ro) |
| 74 |
return; /* got the wrong guy */ |
| 75 |
dir_check(m); |
| 76 |
/* compute first projection */ |
| 77 |
if (m->otype == MAT_DIRECT1 || |
| 78 |
(r->rsrc < 0 || source[r->rsrc].sa.sv.pn == 0)) |
| 79 |
redirect(m, r, 0); |
| 80 |
/* compute second projection */ |
| 81 |
if (m->otype == MAT_DIRECT2 && |
| 82 |
(r->rsrc < 0 || source[r->rsrc].sa.sv.pn == 1)) |
| 83 |
redirect(m, r, 1); |
| 84 |
} |
| 85 |
|
| 86 |
|
| 87 |
redirect(m, r, n) /* compute n'th ray redirection */ |
| 88 |
OBJREC *m; |
| 89 |
RAY *r; |
| 90 |
int n; |
| 91 |
{ |
| 92 |
register char **sa; |
| 93 |
RAY nr; |
| 94 |
double coef; |
| 95 |
register int j; |
| 96 |
/* set up function */ |
| 97 |
setmap(m, r, &((FULLXF *)m->os)->b); |
| 98 |
funcfile(m->oargs.sarg[fndx(m)]); |
| 99 |
sa = m->oargs.sarg + 4*n; |
| 100 |
/* compute coefficient */ |
| 101 |
errno = 0; |
| 102 |
coef = varvalue(sa[0]); |
| 103 |
if (errno) |
| 104 |
goto computerr; |
| 105 |
if (coef <= FTINY || rayorigin(&nr, r, TRANS, coef) < 0) |
| 106 |
return(0); |
| 107 |
/* compute direction */ |
| 108 |
errno = 0; |
| 109 |
for (j = 0; j < 3; j++) |
| 110 |
nr.rdir[j] = varvalue(sa[j+1]); |
| 111 |
if (errno) |
| 112 |
goto computerr; |
| 113 |
multv3(nr.rdir, nr.rdir, ((FULLXF *)m->os)->f.xfm); |
| 114 |
if (r->rox != NULL) |
| 115 |
multv3(nr.rdir, nr.rdir, r->rox->f.xfm); |
| 116 |
if (normalize(nr.rdir) == 0.0) |
| 117 |
goto computerr; |
| 118 |
/* compute value */ |
| 119 |
if (r->rsrc >= 0) |
| 120 |
nr.rsrc = source[r->rsrc].sa.sv.sn; |
| 121 |
rayvalue(&nr); |
| 122 |
scalecolor(nr.rcol, coef); |
| 123 |
addcolor(r->rcol, nr.rcol); |
| 124 |
return(1); |
| 125 |
computerr: |
| 126 |
objerror(m, WARNING, "compute error"); |
| 127 |
return(-1); |
| 128 |
} |
| 129 |
|
| 130 |
|
| 131 |
dir_proj(pm, o, s, n) /* compute a director's projection */ |
| 132 |
MAT4 pm; |
| 133 |
OBJREC *o; |
| 134 |
SRCREC *s; |
| 135 |
int n; |
| 136 |
{ |
| 137 |
RAY tr; |
| 138 |
register OBJREC *m; |
| 139 |
char **sa; |
| 140 |
FVECT cent, newdir, nv, h; |
| 141 |
double olddot, newdot, od; |
| 142 |
register int i, j; |
| 143 |
/* get material arguments */ |
| 144 |
m = objptr(o->omod); |
| 145 |
dir_check(m); |
| 146 |
sa = m->oargs.sarg + 4*n; |
| 147 |
/* initialize test ray */ |
| 148 |
getmaxdisk(cent, o); |
| 149 |
if (s->sflags & SDISTANT) |
| 150 |
for (i = 0; i < 3; i++) { |
| 151 |
tr.rdir[i] = -s->sloc[i]; |
| 152 |
tr.rorg[i] = cent[i] - tr.rdir[i]; |
| 153 |
} |
| 154 |
else { |
| 155 |
for (i = 0; i < 3; i++) { |
| 156 |
tr.rdir[i] = cent[i] - s->sloc[i]; |
| 157 |
tr.rorg[i] = s->sloc[i]; |
| 158 |
} |
| 159 |
if (normalize(tr.rdir) == 0.0) |
| 160 |
return(0); /* at source! */ |
| 161 |
} |
| 162 |
od = getplaneq(nv, o); |
| 163 |
olddot = DOT(tr.rdir, nv); |
| 164 |
if (olddot <= FTINY && olddot >= -FTINY) |
| 165 |
return(0); /* old dir parallels plane */ |
| 166 |
rayorigin(&tr, NULL, PRIMARY, 1.0); |
| 167 |
if (!(*ofun[o->otype].funp)(o, &tr)) |
| 168 |
return(0); /* no intersection! */ |
| 169 |
/* compute redirection */ |
| 170 |
setmap(m, &tr, &((FULLXF *)m->os)->b); |
| 171 |
funcfile(m->oargs.sarg[fndx(m)]); |
| 172 |
errno = 0; |
| 173 |
if (varvalue(sa[0]) <= FTINY) |
| 174 |
return(0); /* insignificant */ |
| 175 |
if (errno) |
| 176 |
goto computerr; |
| 177 |
for (i = 0; i < 3; i++) |
| 178 |
newdir[i] = varvalue(sa[i+1]); |
| 179 |
if (errno) |
| 180 |
goto computerr; |
| 181 |
multv3(newdir, newdir, ((FULLXF *)m->os)->f.xfm); |
| 182 |
/* normalization unnecessary */ |
| 183 |
newdot = DOT(newdir, nv); |
| 184 |
if (newdot <= FTINY && newdot >= -FTINY) |
| 185 |
return(0); /* new dir parallels plane */ |
| 186 |
/* everything OK -- compute shear */ |
| 187 |
for (i = 0; i < 3; i++) |
| 188 |
h[i] = newdir[i]/newdot - tr.rdir[i]/olddot; |
| 189 |
setident4(pm); |
| 190 |
for (j = 0; j < 3; j++) { |
| 191 |
for (i = 0; i < 3; i++) |
| 192 |
pm[i][j] += nv[i]*h[j]; |
| 193 |
pm[3][j] = -od*h[j]; |
| 194 |
} |
| 195 |
if (newdot > 0.0 ^ olddot > 0.0) /* add mirroring */ |
| 196 |
for (j = 0; j < 3; j++) { |
| 197 |
for (i = 0; i < 3; i++) |
| 198 |
pm[i][j] -= 2.*nv[i]*nv[j]; |
| 199 |
pm[3][j] += 2.*od*nv[j]; |
| 200 |
} |
| 201 |
return(1); |
| 202 |
computerr: |
| 203 |
objerror(m, WARNING, "projection compute error"); |
| 204 |
return(0); |
| 205 |
} |
