1 |
greg |
1.1 |
#ifndef lint |
2 |
greg |
2.16 |
static const char RCSid[] = "$Id: m_mirror.c,v 2.15 2014/01/25 18:27:39 greg Exp $"; |
3 |
greg |
1.1 |
#endif |
4 |
|
|
/* |
5 |
|
|
* Routines for mirror material supporting virtual light sources |
6 |
|
|
*/ |
7 |
|
|
|
8 |
greg |
2.9 |
#include "copyright.h" |
9 |
greg |
2.8 |
|
10 |
greg |
1.1 |
#include "ray.h" |
11 |
|
|
#include "otypes.h" |
12 |
schorsch |
2.10 |
#include "rtotypes.h" |
13 |
greg |
1.1 |
#include "source.h" |
14 |
|
|
|
15 |
|
|
/* |
16 |
|
|
* The real arguments for MAT_MIRROR are simply: |
17 |
|
|
* |
18 |
|
|
* 3 rrefl grefl brefl |
19 |
|
|
* |
20 |
|
|
* Additionally, the user may specify a single string argument |
21 |
|
|
* which is interpreted as the name of the material to use |
22 |
|
|
* instead of the mirror if the ray being considered is not |
23 |
|
|
* part of the direct calculation. |
24 |
|
|
*/ |
25 |
|
|
|
26 |
schorsch |
2.10 |
static int mir_proj(MAT4 pm, OBJREC *o, SRCREC *s, int n); |
27 |
|
|
static void mirrorproj(MAT4 m, FVECT nv, double offs); |
28 |
greg |
2.8 |
|
29 |
greg |
1.1 |
VSMATERIAL mirror_vs = {mir_proj, 1}; |
30 |
|
|
|
31 |
|
|
|
32 |
greg |
2.16 |
int |
33 |
schorsch |
2.10 |
m_mirror( /* shade mirrored ray */ |
34 |
greg |
2.16 |
OBJREC *m, |
35 |
|
|
RAY *r |
36 |
schorsch |
2.10 |
) |
37 |
greg |
1.1 |
{ |
38 |
|
|
COLOR mcolor; |
39 |
|
|
RAY nr; |
40 |
greg |
2.6 |
int rpure = 1; |
41 |
greg |
2.16 |
int i; |
42 |
greg |
1.1 |
/* check arguments */ |
43 |
|
|
if (m->oargs.nfargs != 3 || m->oargs.nsargs > 1) |
44 |
|
|
objerror(m, USER, "bad number of arguments"); |
45 |
greg |
1.3 |
/* check for substitute material */ |
46 |
greg |
2.14 |
/* but avoid double-counting */ |
47 |
|
|
if (m->oargs.nsargs > 0 && !(r->crtype & (AMBIENT|SPECULAR)) && |
48 |
greg |
1.3 |
(r->rsrc < 0 || source[r->rsrc].so != r->ro)) { |
49 |
greg |
2.4 |
if (!strcmp(m->oargs.sarg[0], VOIDID)) { |
50 |
|
|
raytrans(r); |
51 |
|
|
return(1); |
52 |
|
|
} |
53 |
gwlarson |
2.7 |
return(rayshade(r, lastmod(objndx(m), m->oargs.sarg[0]))); |
54 |
greg |
1.1 |
} |
55 |
greg |
1.3 |
/* check for bad source ray */ |
56 |
|
|
if (r->rsrc >= 0 && source[r->rsrc].so != r->ro) |
57 |
greg |
2.3 |
return(1); |
58 |
greg |
1.3 |
|
59 |
greg |
2.15 |
if (r->rod < 0.) { /* back is black */ |
60 |
|
|
if (!backvis) |
61 |
|
|
raytrans(r); /* unless back visibility is off */ |
62 |
greg |
2.3 |
return(1); |
63 |
greg |
2.15 |
} |
64 |
greg |
1.1 |
/* get modifiers */ |
65 |
|
|
raytexture(r, m->omod); |
66 |
|
|
/* assign material color */ |
67 |
|
|
setcolor(mcolor, m->oargs.farg[0], |
68 |
|
|
m->oargs.farg[1], |
69 |
|
|
m->oargs.farg[2]); |
70 |
|
|
multcolor(mcolor, r->pcol); |
71 |
|
|
/* compute reflected ray */ |
72 |
|
|
if (r->rsrc >= 0) { /* relayed light source */ |
73 |
greg |
2.11 |
rayorigin(&nr, REFLECTED, r, mcolor); |
74 |
greg |
1.1 |
/* ignore textures */ |
75 |
|
|
for (i = 0; i < 3; i++) |
76 |
|
|
nr.rdir[i] = r->rdir[i] + 2.*r->rod*r->ron[i]; |
77 |
|
|
/* source we're aiming for next */ |
78 |
greg |
1.2 |
nr.rsrc = source[r->rsrc].sa.sv.sn; |
79 |
greg |
1.1 |
} else { /* ordinary reflection */ |
80 |
|
|
FVECT pnorm; |
81 |
|
|
double pdot; |
82 |
|
|
|
83 |
greg |
2.11 |
if (rayorigin(&nr, REFLECTED, r, mcolor) < 0) |
84 |
greg |
2.3 |
return(1); |
85 |
greg |
2.16 |
if (!(r->crtype & AMBIENT) && |
86 |
|
|
DOT(r->pert,r->pert) > FTINY*FTINY) { |
87 |
greg |
2.6 |
pdot = raynormal(pnorm, r); /* use textures */ |
88 |
|
|
for (i = 0; i < 3; i++) |
89 |
|
|
nr.rdir[i] = r->rdir[i] + 2.*pdot*pnorm[i]; |
90 |
|
|
rpure = 0; |
91 |
|
|
} |
92 |
greg |
2.2 |
/* check for penetration */ |
93 |
greg |
2.6 |
if (rpure || DOT(nr.rdir, r->ron) <= FTINY) |
94 |
greg |
2.2 |
for (i = 0; i < 3; i++) |
95 |
|
|
nr.rdir[i] = r->rdir[i] + 2.*r->rod*r->ron[i]; |
96 |
greg |
1.1 |
} |
97 |
greg |
2.13 |
checknorm(nr.rdir); |
98 |
greg |
1.1 |
rayvalue(&nr); |
99 |
greg |
2.11 |
multcolor(nr.rcol, nr.rcoef); |
100 |
greg |
1.1 |
addcolor(r->rcol, nr.rcol); |
101 |
greg |
2.6 |
if (rpure && r->ro != NULL && isflat(r->ro->otype)) |
102 |
|
|
r->rt = r->rot + nr.rt; |
103 |
greg |
2.3 |
return(1); |
104 |
greg |
1.1 |
} |
105 |
|
|
|
106 |
|
|
|
107 |
greg |
2.8 |
static int |
108 |
schorsch |
2.10 |
mir_proj( /* compute a mirror's projection */ |
109 |
|
|
MAT4 pm, |
110 |
greg |
2.16 |
OBJREC *o, |
111 |
schorsch |
2.10 |
SRCREC *s, |
112 |
|
|
int n |
113 |
|
|
) |
114 |
greg |
1.1 |
{ |
115 |
greg |
2.12 |
double corr = 1.; |
116 |
greg |
2.5 |
FVECT nv, sc; |
117 |
greg |
2.12 |
double od, offs; |
118 |
|
|
int i; |
119 |
greg |
1.1 |
/* get surface normal and offset */ |
120 |
greg |
2.12 |
offs = od = getplaneq(nv, o); |
121 |
|
|
if (s->sflags & SDISTANT) |
122 |
|
|
offs = 0.; |
123 |
|
|
/* check for extreme point behind */ |
124 |
|
|
if (s->sflags & SCIR) { |
125 |
|
|
if (s->sflags & (SFLAT|SDISTANT)) |
126 |
|
|
corr = 1.12837917; /* correct setflatss() */ |
127 |
|
|
else |
128 |
|
|
corr = 1.0/0.7236; /* correct sphsetsrc() */ |
129 |
|
|
} |
130 |
greg |
2.5 |
VCOPY(sc, s->sloc); |
131 |
|
|
for (i = s->sflags & SFLAT ? SV : SW; i >= 0; i--) |
132 |
greg |
2.12 |
if (DOT(nv, s->ss[i]) > offs) |
133 |
|
|
VSUM(sc, sc, s->ss[i], corr); |
134 |
greg |
2.5 |
else |
135 |
greg |
2.12 |
VSUM(sc, sc, s->ss[i], -corr); |
136 |
|
|
if (DOT(sc, nv) <= offs+FTINY) |
137 |
greg |
1.1 |
return(0); |
138 |
|
|
/* everything OK -- compute projection */ |
139 |
|
|
mirrorproj(pm, nv, od); |
140 |
|
|
return(1); |
141 |
|
|
} |
142 |
|
|
|
143 |
|
|
|
144 |
schorsch |
2.10 |
static void |
145 |
|
|
mirrorproj( /* get mirror projection for surface */ |
146 |
greg |
2.16 |
MAT4 m, |
147 |
schorsch |
2.10 |
FVECT nv, |
148 |
|
|
double offs |
149 |
|
|
) |
150 |
greg |
1.1 |
{ |
151 |
greg |
2.16 |
int i, j; |
152 |
greg |
1.1 |
/* assign matrix */ |
153 |
|
|
setident4(m); |
154 |
greg |
1.2 |
for (j = 0; j < 3; j++) { |
155 |
|
|
for (i = 0; i < 3; i++) |
156 |
greg |
1.1 |
m[i][j] -= 2.*nv[i]*nv[j]; |
157 |
|
|
m[3][j] = 2.*offs*nv[j]; |
158 |
greg |
1.2 |
} |
159 |
greg |
1.1 |
} |