| 1 |
#ifndef lint |
| 2 |
static const char RCSid[] = "$Id: m_direct.c,v 2.11 2003/07/27 22:12:03 schorsch Exp $"; |
| 3 |
#endif |
| 4 |
/* |
| 5 |
* Routines for light-redirecting materials and |
| 6 |
* their associated virtual light sources |
| 7 |
*/ |
| 8 |
|
| 9 |
#include "copyright.h" |
| 10 |
|
| 11 |
#include "ray.h" |
| 12 |
#include "otypes.h" |
| 13 |
#include "rtotypes.h" |
| 14 |
#include "source.h" |
| 15 |
#include "func.h" |
| 16 |
|
| 17 |
/* |
| 18 |
* The arguments for MAT_DIRECT1 are: |
| 19 |
* |
| 20 |
* 5+ coef1 dx1 dy1 dz1 funcfile transform.. |
| 21 |
* 0 |
| 22 |
* n A1 A2 .. An |
| 23 |
* |
| 24 |
* The arguments for MAT_DIRECT2 are: |
| 25 |
* |
| 26 |
* 9+ coef1 dx1 dy1 dz1 coef2 dx2 dy2 dz2 funcfile transform.. |
| 27 |
* 0 |
| 28 |
* n A1 A2 .. An |
| 29 |
*/ |
| 30 |
|
| 31 |
static int redirect(OBJREC *m, RAY *r, int n); |
| 32 |
static int dir_proj(MAT4 pm, OBJREC *o, SRCREC *s, int n); |
| 33 |
|
| 34 |
VSMATERIAL direct1_vs = {dir_proj, 1}; |
| 35 |
VSMATERIAL direct2_vs = {dir_proj, 2}; |
| 36 |
|
| 37 |
#define getdfunc(m) ( (m)->otype == MAT_DIRECT1 ? \ |
| 38 |
getfunc(m, 4, 0xf, 1) : \ |
| 39 |
getfunc(m, 8, 0xff, 1) ) |
| 40 |
|
| 41 |
|
| 42 |
extern int |
| 43 |
m_direct( /* shade redirected ray */ |
| 44 |
register OBJREC *m, |
| 45 |
register RAY *r |
| 46 |
) |
| 47 |
{ |
| 48 |
/* check if source ray */ |
| 49 |
if (r->rsrc >= 0 && source[r->rsrc].so != r->ro) |
| 50 |
return(1); /* got the wrong guy */ |
| 51 |
/* compute first projection */ |
| 52 |
if (m->otype == MAT_DIRECT1 || |
| 53 |
(r->rsrc < 0 || source[r->rsrc].sa.sv.pn == 0)) |
| 54 |
redirect(m, r, 0); |
| 55 |
/* compute second projection */ |
| 56 |
if (m->otype == MAT_DIRECT2 && |
| 57 |
(r->rsrc < 0 || source[r->rsrc].sa.sv.pn == 1)) |
| 58 |
redirect(m, r, 1); |
| 59 |
return(1); |
| 60 |
} |
| 61 |
|
| 62 |
|
| 63 |
static int |
| 64 |
redirect( /* compute n'th ray redirection */ |
| 65 |
OBJREC *m, |
| 66 |
RAY *r, |
| 67 |
int n |
| 68 |
) |
| 69 |
{ |
| 70 |
MFUNC *mf; |
| 71 |
register EPNODE **va; |
| 72 |
FVECT nsdir; |
| 73 |
RAY nr; |
| 74 |
double coef; |
| 75 |
register int j; |
| 76 |
/* set up function */ |
| 77 |
mf = getdfunc(m); |
| 78 |
setfunc(m, r); |
| 79 |
/* assign direction variable */ |
| 80 |
if (r->rsrc >= 0) { |
| 81 |
register SRCREC *sp = source + source[r->rsrc].sa.sv.sn; |
| 82 |
|
| 83 |
if (sp->sflags & SDISTANT) |
| 84 |
VCOPY(nsdir, sp->sloc); |
| 85 |
else { |
| 86 |
for (j = 0; j < 3; j++) |
| 87 |
nsdir[j] = sp->sloc[j] - r->rop[j]; |
| 88 |
normalize(nsdir); |
| 89 |
} |
| 90 |
multv3(nsdir, nsdir, funcxf.xfm); |
| 91 |
varset("DxA", '=', nsdir[0]/funcxf.sca); |
| 92 |
varset("DyA", '=', nsdir[1]/funcxf.sca); |
| 93 |
varset("DzA", '=', nsdir[2]/funcxf.sca); |
| 94 |
} else { |
| 95 |
varset("DxA", '=', 0.0); |
| 96 |
varset("DyA", '=', 0.0); |
| 97 |
varset("DzA", '=', 0.0); |
| 98 |
} |
| 99 |
/* compute coefficient */ |
| 100 |
errno = 0; |
| 101 |
va = mf->ep + 4*n; |
| 102 |
coef = evalue(va[0]); |
| 103 |
if (errno == EDOM || errno == ERANGE) |
| 104 |
goto computerr; |
| 105 |
if (coef <= FTINY || rayorigin(&nr, r, TRANS, coef) < 0) |
| 106 |
return(0); |
| 107 |
va++; /* compute direction */ |
| 108 |
for (j = 0; j < 3; j++) { |
| 109 |
nr.rdir[j] = evalue(va[j]); |
| 110 |
if (errno == EDOM || errno == ERANGE) |
| 111 |
goto computerr; |
| 112 |
} |
| 113 |
if (mf->f != &unitxf) |
| 114 |
multv3(nr.rdir, nr.rdir, mf->f->xfm); |
| 115 |
if (r->rox != NULL) |
| 116 |
multv3(nr.rdir, nr.rdir, r->rox->f.xfm); |
| 117 |
if (normalize(nr.rdir) == 0.0) |
| 118 |
goto computerr; |
| 119 |
/* compute value */ |
| 120 |
if (r->rsrc >= 0) |
| 121 |
nr.rsrc = source[r->rsrc].sa.sv.sn; |
| 122 |
rayvalue(&nr); |
| 123 |
scalecolor(nr.rcol, coef); |
| 124 |
addcolor(r->rcol, nr.rcol); |
| 125 |
if (r->ro != NULL && isflat(r->ro->otype)) |
| 126 |
r->rt = r->rot + nr.rt; |
| 127 |
return(1); |
| 128 |
computerr: |
| 129 |
objerror(m, WARNING, "compute error"); |
| 130 |
return(-1); |
| 131 |
} |
| 132 |
|
| 133 |
|
| 134 |
static int |
| 135 |
dir_proj( /* compute a director's projection */ |
| 136 |
MAT4 pm, |
| 137 |
OBJREC *o, |
| 138 |
SRCREC *s, |
| 139 |
int n |
| 140 |
) |
| 141 |
{ |
| 142 |
RAY tr; |
| 143 |
OBJREC *m; |
| 144 |
MFUNC *mf; |
| 145 |
EPNODE **va; |
| 146 |
FVECT cent, newdir, nv, h; |
| 147 |
double coef, olddot, newdot, od; |
| 148 |
register int i, j; |
| 149 |
/* initialize test ray */ |
| 150 |
getmaxdisk(cent, o); |
| 151 |
if (s->sflags & SDISTANT) |
| 152 |
for (i = 0; i < 3; i++) { |
| 153 |
tr.rdir[i] = -s->sloc[i]; |
| 154 |
tr.rorg[i] = cent[i] - tr.rdir[i]; |
| 155 |
} |
| 156 |
else { |
| 157 |
for (i = 0; i < 3; i++) { |
| 158 |
tr.rdir[i] = cent[i] - s->sloc[i]; |
| 159 |
tr.rorg[i] = s->sloc[i]; |
| 160 |
} |
| 161 |
if (normalize(tr.rdir) == 0.0) |
| 162 |
return(0); /* at source! */ |
| 163 |
} |
| 164 |
od = getplaneq(nv, o); |
| 165 |
olddot = DOT(tr.rdir, nv); |
| 166 |
if (olddot <= FTINY && olddot >= -FTINY) |
| 167 |
return(0); /* old dir parallels plane */ |
| 168 |
tr.rmax = 0.0; |
| 169 |
rayorigin(&tr, NULL, PRIMARY, 1.0); |
| 170 |
if (!(*ofun[o->otype].funp)(o, &tr)) |
| 171 |
return(0); /* no intersection! */ |
| 172 |
/* compute redirection */ |
| 173 |
m = vsmaterial(o); |
| 174 |
mf = getdfunc(m); |
| 175 |
setfunc(m, &tr); |
| 176 |
varset("DxA", '=', 0.0); |
| 177 |
varset("DyA", '=', 0.0); |
| 178 |
varset("DzA", '=', 0.0); |
| 179 |
errno = 0; |
| 180 |
va = mf->ep + 4*n; |
| 181 |
coef = evalue(va[0]); |
| 182 |
if (errno == EDOM || errno == ERANGE) |
| 183 |
goto computerr; |
| 184 |
if (coef <= FTINY) |
| 185 |
return(0); /* insignificant */ |
| 186 |
va++; |
| 187 |
for (i = 0; i < 3; i++) { |
| 188 |
newdir[i] = evalue(va[i]); |
| 189 |
if (errno == EDOM || errno == ERANGE) |
| 190 |
goto computerr; |
| 191 |
} |
| 192 |
if (mf->f != &unitxf) |
| 193 |
multv3(newdir, newdir, mf->f->xfm); |
| 194 |
/* normalization unnecessary */ |
| 195 |
newdot = DOT(newdir, nv); |
| 196 |
if (newdot <= FTINY && newdot >= -FTINY) |
| 197 |
return(0); /* new dir parallels plane */ |
| 198 |
/* everything OK -- compute shear */ |
| 199 |
for (i = 0; i < 3; i++) |
| 200 |
h[i] = newdir[i]/newdot - tr.rdir[i]/olddot; |
| 201 |
setident4(pm); |
| 202 |
for (j = 0; j < 3; j++) { |
| 203 |
for (i = 0; i < 3; i++) |
| 204 |
pm[i][j] += nv[i]*h[j]; |
| 205 |
pm[3][j] = -od*h[j]; |
| 206 |
} |
| 207 |
if ((newdot > 0.0) ^ (olddot > 0.0)) /* add mirroring */ |
| 208 |
for (j = 0; j < 3; j++) { |
| 209 |
for (i = 0; i < 3; i++) |
| 210 |
pm[i][j] -= 2.*nv[i]*nv[j]; |
| 211 |
pm[3][j] += 2.*od*nv[j]; |
| 212 |
} |
| 213 |
return(1); |
| 214 |
computerr: |
| 215 |
objerror(m, WARNING, "projection compute error"); |
| 216 |
return(0); |
| 217 |
} |
