1 |
#ifndef lint |
2 |
static const char RCSid[] = "$Id$"; |
3 |
#endif |
4 |
/* |
5 |
* Routines for mirror material supporting virtual light sources |
6 |
*/ |
7 |
|
8 |
/* ==================================================================== |
9 |
* The Radiance Software License, Version 1.0 |
10 |
* |
11 |
* Copyright (c) 1990 - 2002 The Regents of the University of California, |
12 |
* through Lawrence Berkeley National Laboratory. All rights reserved. |
13 |
* |
14 |
* Redistribution and use in source and binary forms, with or without |
15 |
* modification, are permitted provided that the following conditions |
16 |
* are met: |
17 |
* |
18 |
* 1. Redistributions of source code must retain the above copyright |
19 |
* notice, this list of conditions and the following disclaimer. |
20 |
* |
21 |
* 2. Redistributions in binary form must reproduce the above copyright |
22 |
* notice, this list of conditions and the following disclaimer in |
23 |
* the documentation and/or other materials provided with the |
24 |
* distribution. |
25 |
* |
26 |
* 3. The end-user documentation included with the redistribution, |
27 |
* if any, must include the following acknowledgment: |
28 |
* "This product includes Radiance software |
29 |
* (http://radsite.lbl.gov/) |
30 |
* developed by the Lawrence Berkeley National Laboratory |
31 |
* (http://www.lbl.gov/)." |
32 |
* Alternately, this acknowledgment may appear in the software itself, |
33 |
* if and wherever such third-party acknowledgments normally appear. |
34 |
* |
35 |
* 4. The names "Radiance," "Lawrence Berkeley National Laboratory" |
36 |
* and "The Regents of the University of California" must |
37 |
* not be used to endorse or promote products derived from this |
38 |
* software without prior written permission. For written |
39 |
* permission, please contact [email protected]. |
40 |
* |
41 |
* 5. Products derived from this software may not be called "Radiance", |
42 |
* nor may "Radiance" appear in their name, without prior written |
43 |
* permission of Lawrence Berkeley National Laboratory. |
44 |
* |
45 |
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED |
46 |
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
47 |
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
48 |
* DISCLAIMED. IN NO EVENT SHALL Lawrence Berkeley National Laboratory OR |
49 |
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
50 |
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
51 |
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
52 |
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
53 |
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
54 |
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
55 |
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
56 |
* SUCH DAMAGE. |
57 |
* ==================================================================== |
58 |
* |
59 |
* This software consists of voluntary contributions made by many |
60 |
* individuals on behalf of Lawrence Berkeley National Laboratory. For more |
61 |
* information on Lawrence Berkeley National Laboratory, please see |
62 |
* <http://www.lbl.gov/>. |
63 |
*/ |
64 |
|
65 |
#include "ray.h" |
66 |
|
67 |
#include "otypes.h" |
68 |
|
69 |
#include "source.h" |
70 |
|
71 |
/* |
72 |
* The real arguments for MAT_MIRROR are simply: |
73 |
* |
74 |
* 3 rrefl grefl brefl |
75 |
* |
76 |
* Additionally, the user may specify a single string argument |
77 |
* which is interpreted as the name of the material to use |
78 |
* instead of the mirror if the ray being considered is not |
79 |
* part of the direct calculation. |
80 |
*/ |
81 |
|
82 |
|
83 |
static int mir_proj(), mirrorproj(); |
84 |
|
85 |
VSMATERIAL mirror_vs = {mir_proj, 1}; |
86 |
|
87 |
|
88 |
int |
89 |
m_mirror(m, r) /* shade mirrored ray */ |
90 |
register OBJREC *m; |
91 |
register RAY *r; |
92 |
{ |
93 |
COLOR mcolor; |
94 |
RAY nr; |
95 |
int rpure = 1; |
96 |
register int i; |
97 |
/* check arguments */ |
98 |
if (m->oargs.nfargs != 3 || m->oargs.nsargs > 1) |
99 |
objerror(m, USER, "bad number of arguments"); |
100 |
/* check for substitute material */ |
101 |
if (m->oargs.nsargs > 0 && |
102 |
(r->rsrc < 0 || source[r->rsrc].so != r->ro)) { |
103 |
if (!strcmp(m->oargs.sarg[0], VOIDID)) { |
104 |
raytrans(r); |
105 |
return(1); |
106 |
} |
107 |
return(rayshade(r, lastmod(objndx(m), m->oargs.sarg[0]))); |
108 |
} |
109 |
/* check for bad source ray */ |
110 |
if (r->rsrc >= 0 && source[r->rsrc].so != r->ro) |
111 |
return(1); |
112 |
|
113 |
if (r->rod < 0.) /* back is black */ |
114 |
return(1); |
115 |
/* get modifiers */ |
116 |
raytexture(r, m->omod); |
117 |
/* assign material color */ |
118 |
setcolor(mcolor, m->oargs.farg[0], |
119 |
m->oargs.farg[1], |
120 |
m->oargs.farg[2]); |
121 |
multcolor(mcolor, r->pcol); |
122 |
/* compute reflected ray */ |
123 |
if (r->rsrc >= 0) { /* relayed light source */ |
124 |
rayorigin(&nr, r, REFLECTED, 1.); |
125 |
/* ignore textures */ |
126 |
for (i = 0; i < 3; i++) |
127 |
nr.rdir[i] = r->rdir[i] + 2.*r->rod*r->ron[i]; |
128 |
/* source we're aiming for next */ |
129 |
nr.rsrc = source[r->rsrc].sa.sv.sn; |
130 |
} else { /* ordinary reflection */ |
131 |
FVECT pnorm; |
132 |
double pdot; |
133 |
|
134 |
if (rayorigin(&nr, r, REFLECTED, bright(mcolor)) < 0) |
135 |
return(1); |
136 |
if (DOT(r->pert,r->pert) > FTINY*FTINY) { |
137 |
pdot = raynormal(pnorm, r); /* use textures */ |
138 |
for (i = 0; i < 3; i++) |
139 |
nr.rdir[i] = r->rdir[i] + 2.*pdot*pnorm[i]; |
140 |
rpure = 0; |
141 |
} |
142 |
/* check for penetration */ |
143 |
if (rpure || DOT(nr.rdir, r->ron) <= FTINY) |
144 |
for (i = 0; i < 3; i++) |
145 |
nr.rdir[i] = r->rdir[i] + 2.*r->rod*r->ron[i]; |
146 |
} |
147 |
rayvalue(&nr); |
148 |
multcolor(nr.rcol, mcolor); |
149 |
addcolor(r->rcol, nr.rcol); |
150 |
if (rpure && r->ro != NULL && isflat(r->ro->otype)) |
151 |
r->rt = r->rot + nr.rt; |
152 |
return(1); |
153 |
} |
154 |
|
155 |
|
156 |
static int |
157 |
mir_proj(pm, o, s, n) /* compute a mirror's projection */ |
158 |
MAT4 pm; |
159 |
register OBJREC *o; |
160 |
SRCREC *s; |
161 |
int n; |
162 |
{ |
163 |
FVECT nv, sc; |
164 |
double od; |
165 |
register int i, j; |
166 |
/* get surface normal and offset */ |
167 |
od = getplaneq(nv, o); |
168 |
/* check for extreme point for behind */ |
169 |
VCOPY(sc, s->sloc); |
170 |
for (i = s->sflags & SFLAT ? SV : SW; i >= 0; i--) |
171 |
if (DOT(nv, s->ss[i]) > 0.) |
172 |
for (j = 0; j < 3; j++) |
173 |
sc[j] += s->ss[i][j]; |
174 |
else |
175 |
for (j = 0; j < 3; j++) |
176 |
sc[j] -= s->ss[i][j]; |
177 |
if (DOT(sc, nv) <= (s->sflags & SDISTANT ? FTINY : od+FTINY)) |
178 |
return(0); |
179 |
/* everything OK -- compute projection */ |
180 |
mirrorproj(pm, nv, od); |
181 |
return(1); |
182 |
} |
183 |
|
184 |
|
185 |
static int |
186 |
mirrorproj(m, nv, offs) /* get mirror projection for surface */ |
187 |
register MAT4 m; |
188 |
FVECT nv; |
189 |
double offs; |
190 |
{ |
191 |
register int i, j; |
192 |
/* assign matrix */ |
193 |
setident4(m); |
194 |
for (j = 0; j < 3; j++) { |
195 |
for (i = 0; i < 3; i++) |
196 |
m[i][j] -= 2.*nv[i]*nv[j]; |
197 |
m[3][j] = 2.*offs*nv[j]; |
198 |
} |
199 |
} |