1 |
greg |
1.1 |
/* Copyright (c) 1991 Regents of the University of California */ |
2 |
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3 |
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#ifndef lint |
4 |
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static char SCCSid[] = "$SunId$ LBL"; |
5 |
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#endif |
6 |
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7 |
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/* |
8 |
greg |
1.9 |
* Compute Glare Index given by program name or -t option: |
9 |
greg |
1.1 |
* |
10 |
greg |
2.4 |
* dgi - Daylight Glare Index |
11 |
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* brs_gi - Building Research Station Glare Index (Petherbridge |
12 |
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* & Hopkinson) |
13 |
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* ugr - Unified Glare Rating System (Fischer) |
14 |
greg |
1.2 |
* guth_dgr - Guth discomfort glare rating |
15 |
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* guth_vcp - Guth visual comfort probability |
16 |
greg |
1.9 |
* cie_cgi - CIE Glare Index (1983, due to Einhorn) |
17 |
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* vert_dir - Direct vertical illuminance |
18 |
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* vert_ind - Indirect vertical illuminance (from input) |
19 |
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* vert_ill - Total vertical illuminance |
20 |
greg |
1.1 |
* |
21 |
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* 12 April 1991 Greg Ward EPFL |
22 |
greg |
2.4 |
* 19 April 1993 R. Compagnon EPFL (added dgi, brs_gi, ugr) |
23 |
greg |
1.1 |
*/ |
24 |
greg |
2.4 |
|
25 |
greg |
1.1 |
#include "standard.h" |
26 |
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#include "view.h" |
27 |
greg |
2.4 |
|
28 |
greg |
1.1 |
extern double erfc(); |
29 |
greg |
2.4 |
|
30 |
greg |
1.1 |
double posindex(); |
31 |
greg |
2.4 |
|
32 |
greg |
1.9 |
double direct(), guth_dgr(), guth_vcp(), cie_cgi(), |
33 |
greg |
2.4 |
indirect(), total(), dgi(), brs_gi(), ugr(); |
34 |
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|
35 |
greg |
1.1 |
struct named_func { |
36 |
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char *name; |
37 |
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double (*func)(); |
38 |
greg |
1.9 |
char *descrip; |
39 |
greg |
1.1 |
} all_funcs[] = { |
40 |
greg |
2.4 |
{"dgi", dgi, "Daylight Glare Index"}, |
41 |
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{"brs_gi", brs_gi, "BRS Glare Index"}, |
42 |
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{"ugr", ugr, "Unified Glare Rating"}, |
43 |
greg |
1.9 |
{"guth_vcp", guth_vcp, "Guth Visual Comfort Probability"}, |
44 |
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{"cie_cgi", cie_cgi, "CIE Glare Index (Einhorn)"}, |
45 |
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{"guth_dgr", guth_dgr, "Guth Disability Glare Rating"}, |
46 |
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{"vert_dir", direct, "Direct Vertical Illuminance"}, |
47 |
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{"vert_ill", total, "Total Vertical Illuminance"}, |
48 |
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{"vert_ind", indirect, "Indirect Vertical Illuminance"}, |
49 |
greg |
1.1 |
{NULL} |
50 |
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}; |
51 |
greg |
2.4 |
|
52 |
greg |
1.1 |
struct glare_src { |
53 |
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FVECT dir; /* source direction */ |
54 |
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double dom; /* solid angle */ |
55 |
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double lum; /* average luminance */ |
56 |
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struct glare_src *next; |
57 |
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} *all_srcs = NULL; |
58 |
greg |
2.4 |
|
59 |
greg |
1.1 |
struct glare_dir { |
60 |
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double ang; /* angle (in radians) */ |
61 |
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double indirect; /* indirect illuminance */ |
62 |
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struct glare_dir *next; |
63 |
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} *all_dirs = NULL; |
64 |
greg |
2.4 |
|
65 |
greg |
1.1 |
#define newp(type) (type *)malloc(sizeof(type)) |
66 |
greg |
2.4 |
|
67 |
greg |
1.1 |
char *progname; |
68 |
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int print_header = 1; |
69 |
greg |
2.4 |
|
70 |
greg |
1.1 |
VIEW midview = STDVIEW; |
71 |
greg |
2.4 |
|
72 |
greg |
1.4 |
int wrongformat = 0; |
73 |
greg |
2.4 |
|
74 |
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|
75 |
greg |
1.1 |
main(argc, argv) |
76 |
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int argc; |
77 |
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char *argv[]; |
78 |
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{ |
79 |
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extern char *rindex(); |
80 |
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struct named_func *funp; |
81 |
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char *progtail; |
82 |
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int i; |
83 |
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/* get program name */ |
84 |
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progname = argv[0]; |
85 |
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progtail = rindex(progname, '/'); /* final component */ |
86 |
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if (progtail == NULL) |
87 |
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progtail = progname; |
88 |
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else |
89 |
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progtail++; |
90 |
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/* get options */ |
91 |
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for (i = 1; i < argc && argv[i][0] == '-'; i++) |
92 |
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switch (argv[i][1]) { |
93 |
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case 't': |
94 |
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progtail = argv[++i]; |
95 |
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break; |
96 |
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case 'h': |
97 |
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print_header = 0; |
98 |
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break; |
99 |
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default: |
100 |
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goto userr; |
101 |
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} |
102 |
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if (i < argc-1) |
103 |
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goto userr; |
104 |
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if (i == argc-1) /* open file */ |
105 |
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if (freopen(argv[i], "r", stdin) == NULL) { |
106 |
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perror(argv[i]); |
107 |
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exit(1); |
108 |
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} |
109 |
greg |
1.9 |
/* find and run calculation */ |
110 |
greg |
1.1 |
for (funp = all_funcs; funp->name != NULL; funp++) |
111 |
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if (!strcmp(funp->name, progtail)) { |
112 |
greg |
1.9 |
init(); |
113 |
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read_input(); |
114 |
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if (print_header) { |
115 |
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printargs(i, argv, stdout); |
116 |
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putchar('\n'); |
117 |
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} |
118 |
greg |
1.1 |
print_values(funp->func); |
119 |
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exit(0); /* we're done */ |
120 |
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} |
121 |
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/* invalid function */ |
122 |
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userr: |
123 |
greg |
1.9 |
fprintf(stderr, "Usage: %s -t type [-h] [input]\n", progname); |
124 |
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fprintf(stderr, "\twhere 'type' is one of the following:\n"); |
125 |
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for (funp = all_funcs; funp->name != NULL; funp++) |
126 |
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fprintf(stderr, "\t%12s\t%s\n", funp->name, funp->descrip); |
127 |
greg |
1.1 |
exit(1); |
128 |
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} |
129 |
greg |
2.4 |
|
130 |
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131 |
greg |
1.1 |
headline(s) /* get line from header */ |
132 |
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char *s; |
133 |
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{ |
134 |
greg |
1.4 |
char fmt[32]; |
135 |
greg |
2.4 |
|
136 |
greg |
1.1 |
if (print_header) /* copy to output */ |
137 |
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fputs(s, stdout); |
138 |
greg |
2.2 |
if (isview(s)) |
139 |
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sscanview(&midview, s); |
140 |
greg |
1.4 |
else if (isformat(s)) { |
141 |
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formatval(fmt, s); |
142 |
greg |
1.6 |
wrongformat = strcmp(fmt, "ascii"); |
143 |
greg |
1.4 |
} |
144 |
greg |
1.1 |
} |
145 |
greg |
2.4 |
|
146 |
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147 |
greg |
1.9 |
init() /* initialize calculation */ |
148 |
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{ |
149 |
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/* read header */ |
150 |
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getheader(stdin, headline, NULL); |
151 |
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if (wrongformat) { |
152 |
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fprintf(stderr, "%s: bad input format\n", progname); |
153 |
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exit(1); |
154 |
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} |
155 |
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/* set view */ |
156 |
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if (setview(&midview) != NULL) { |
157 |
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fprintf(stderr, "%s: bad view information in input\n", |
158 |
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progname); |
159 |
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exit(1); |
160 |
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} |
161 |
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} |
162 |
greg |
2.4 |
|
163 |
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164 |
greg |
1.1 |
read_input() /* read glare sources from stdin */ |
165 |
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{ |
166 |
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#define S_SEARCH 0 |
167 |
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#define S_SOURCE 1 |
168 |
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#define S_DIREC 2 |
169 |
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int state = S_SEARCH; |
170 |
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char buf[128]; |
171 |
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register struct glare_src *gs; |
172 |
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register struct glare_dir *gd; |
173 |
greg |
2.4 |
|
174 |
greg |
1.1 |
while (fgets(buf, sizeof(buf), stdin) != NULL) |
175 |
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switch (state) { |
176 |
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case S_SEARCH: |
177 |
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if (!strcmp(buf, "BEGIN glare source\n")) |
178 |
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state = S_SOURCE; |
179 |
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else if (!strcmp(buf, "BEGIN indirect illuminance\n")) |
180 |
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state = S_DIREC; |
181 |
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break; |
182 |
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case S_SOURCE: |
183 |
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if (!strncmp(buf, "END", 3)) { |
184 |
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state = S_SEARCH; |
185 |
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break; |
186 |
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} |
187 |
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if ((gs = newp(struct glare_src)) == NULL) |
188 |
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goto memerr; |
189 |
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if (sscanf(buf, "%lf %lf %lf %lf %lf", |
190 |
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&gs->dir[0], &gs->dir[1], &gs->dir[2], |
191 |
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&gs->dom, &gs->lum) != 5) |
192 |
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goto readerr; |
193 |
greg |
1.2 |
normalize(gs->dir); |
194 |
greg |
1.1 |
gs->next = all_srcs; |
195 |
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all_srcs = gs; |
196 |
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break; |
197 |
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case S_DIREC: |
198 |
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if (!strncmp(buf, "END", 3)) { |
199 |
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state = S_SEARCH; |
200 |
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break; |
201 |
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} |
202 |
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if ((gd = newp(struct glare_dir)) == NULL) |
203 |
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goto memerr; |
204 |
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if (sscanf(buf, "%lf %lf", |
205 |
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&gd->ang, &gd->indirect) != 2) |
206 |
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goto readerr; |
207 |
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gd->ang *= PI/180.0; /* convert to radians */ |
208 |
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gd->next = all_dirs; |
209 |
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all_dirs = gd; |
210 |
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break; |
211 |
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} |
212 |
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return; |
213 |
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memerr: |
214 |
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perror(progname); |
215 |
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exit(1); |
216 |
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readerr: |
217 |
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fprintf(stderr, "%s: read error on input\n", progname); |
218 |
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exit(1); |
219 |
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#undef S_SEARCH |
220 |
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#undef S_SOURCE |
221 |
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#undef S_DIREC |
222 |
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} |
223 |
greg |
2.4 |
|
224 |
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|
225 |
greg |
1.1 |
print_values(funp) /* print out calculations */ |
226 |
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double (*funp)(); |
227 |
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{ |
228 |
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register struct glare_dir *gd; |
229 |
greg |
2.4 |
|
230 |
greg |
1.1 |
for (gd = all_dirs; gd != NULL; gd = gd->next) |
231 |
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printf("%f\t%f\n", gd->ang*(180.0/PI), (*funp)(gd)); |
232 |
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} |
233 |
greg |
2.4 |
|
234 |
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|
235 |
greg |
1.1 |
double |
236 |
greg |
1.9 |
direct(gd) /* compute direct vertical illuminance */ |
237 |
greg |
1.1 |
struct glare_dir *gd; |
238 |
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{ |
239 |
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FVECT mydir; |
240 |
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double d, dval; |
241 |
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register struct glare_src *gs; |
242 |
greg |
2.4 |
|
243 |
greg |
1.1 |
spinvector(mydir, midview.vdir, midview.vup, gd->ang); |
244 |
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dval = 0.0; |
245 |
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for (gs = all_srcs; gs != NULL; gs = gs->next) { |
246 |
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d = DOT(mydir,gs->dir); |
247 |
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if (d > FTINY) |
248 |
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dval += d * gs->dom * gs->lum; |
249 |
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} |
250 |
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return(dval); |
251 |
greg |
1.9 |
} |
252 |
greg |
2.4 |
|
253 |
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|
254 |
greg |
1.9 |
double |
255 |
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indirect(gd) /* return indirect vertical illuminance */ |
256 |
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struct glare_dir *gd; |
257 |
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{ |
258 |
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return(gd->indirect); |
259 |
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} |
260 |
greg |
2.4 |
|
261 |
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|
262 |
greg |
1.9 |
double |
263 |
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total(gd) /* return total vertical illuminance */ |
264 |
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struct glare_dir *gd; |
265 |
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{ |
266 |
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return(direct(gd)+gd->indirect); |
267 |
greg |
1.1 |
} |
268 |
greg |
2.4 |
|
269 |
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|
270 |
greg |
1.1 |
/* |
271 |
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* posindex - compute glare position index from: |
272 |
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* |
273 |
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* Source Direction |
274 |
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* View Direction |
275 |
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* View Up Direction |
276 |
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* |
277 |
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* All vectors are assumed to be normalized. |
278 |
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* This function is an implementation of the method proposed by |
279 |
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* Robert Levin in his 1975 JIES article. |
280 |
greg |
1.5 |
* This calculation presumes the view direction and up vectors perpendicular. |
281 |
greg |
1.1 |
* We return a value less than zero for improper positions. |
282 |
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*/ |
283 |
greg |
2.4 |
|
284 |
greg |
1.1 |
double |
285 |
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posindex(sd, vd, vu) /* compute position index */ |
286 |
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FVECT sd, vd, vu; |
287 |
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{ |
288 |
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double sigma, tau; |
289 |
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double d; |
290 |
greg |
2.4 |
|
291 |
greg |
1.1 |
d = DOT(sd,vd); |
292 |
|
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if (d <= 0.0) |
293 |
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return(-1.0); |
294 |
greg |
1.5 |
if (d >= 1.0) |
295 |
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return(1.0); |
296 |
greg |
1.1 |
sigma = acos(d) * (180./PI); |
297 |
greg |
2.4 |
d = fabs(DOT(sd,vu)/sqrt(1.0-d*d)); |
298 |
greg |
1.5 |
if (d >= 1.0) |
299 |
|
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tau = 0.0; |
300 |
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else |
301 |
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tau = acos(d) * (180./PI); |
302 |
greg |
1.1 |
return( exp( sigma*( (35.2 - tau*.31889 - 1.22*exp(-.22222*tau))*1e-3 |
303 |
|
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+ sigma*(21. + tau*(.26667 + tau*-.002963))*1e-5 ) |
304 |
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) ); |
305 |
|
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} |
306 |
greg |
2.4 |
|
307 |
|
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|
308 |
|
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double |
309 |
|
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dgi(gd) /* compute Daylight Glare Index */ |
310 |
|
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struct glare_dir *gd; |
311 |
|
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{ |
312 |
|
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register struct glare_src *gs; |
313 |
|
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FVECT mydir,testdir[7],vhor; |
314 |
|
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double r,omega,p[7],sum; |
315 |
|
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int i,n; |
316 |
|
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|
317 |
|
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spinvector(mydir, midview.vdir, midview.vup, gd->ang); |
318 |
|
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sum = 0.0; n = 0; |
319 |
|
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for (gs = all_srcs; gs != NULL; gs = gs->next) { |
320 |
greg |
1.1 |
|
321 |
greg |
2.4 |
/* compute 1/p^2 weighted solid angle of the source */ |
322 |
|
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r = sqrt(1 - pow(1.-gs->dom/2./PI,2.)); |
323 |
|
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fcross(vhor,gs->dir,midview.vup); |
324 |
|
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normalize(vhor); |
325 |
|
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VCOPY(testdir[0],gs->dir); |
326 |
|
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fvsum(testdir[1],gs->dir,vhor,r); |
327 |
|
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fvsum(testdir[2],gs->dir,vhor,0.5*r); |
328 |
|
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fvsum(testdir[5],testdir[2],midview.vup,-0.866*r); |
329 |
|
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fvsum(testdir[2],testdir[2],midview.vup,0.866*r); |
330 |
|
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fvsum(testdir[3],gs->dir,vhor,-r); |
331 |
|
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fvsum(testdir[4],gs->dir,vhor,-0.5*r); |
332 |
|
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fvsum(testdir[6],testdir[4],midview.vup,0.866*r); |
333 |
|
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fvsum(testdir[4],testdir[4],midview.vup,-0.866*r); |
334 |
|
|
for (i = 0; i < 7; i++) { |
335 |
|
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normalize(testdir[i]); |
336 |
|
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p[i] = pow(posindex(testdir[i],mydir,midview.vup),-2.0); |
337 |
|
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if (p[i] <= FTINY) p[i] = 0.0; |
338 |
|
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} |
339 |
|
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r = 1-gs->dom/2./PI; |
340 |
|
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omega = gs->dom*p[0]; |
341 |
|
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omega += (r*PI*(1+1/r/r)-2*PI)*(-p[0]+(p[1]+p[2])*0.5); |
342 |
|
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omega += (2*PI-r*PI*(1+1/r/r))*(-p[0]-0.1667*(p[1]+p[3]) |
343 |
|
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+0.3334*(p[2]+p[4]+p[5]+p[6])); |
344 |
greg |
1.1 |
|
345 |
greg |
2.4 |
sum += pow(gs->lum,1.6) * pow(omega,0.8) / |
346 |
|
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(gd->indirect/PI + 0.07*sqrt(gs->dom)*gs->lum); |
347 |
|
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n++; |
348 |
|
|
} |
349 |
|
|
if (n == 0) |
350 |
|
|
return(0.0); |
351 |
|
|
return( 10*log10(0.478*sum) ); |
352 |
|
|
} |
353 |
|
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|
354 |
|
|
|
355 |
greg |
1.1 |
double |
356 |
greg |
2.4 |
brs_gi(gd) /* compute BRS Glare Index */ |
357 |
|
|
struct glare_dir *gd; |
358 |
|
|
{ |
359 |
|
|
register struct glare_src *gs; |
360 |
|
|
FVECT mydir; |
361 |
|
|
double p; |
362 |
|
|
double sum; |
363 |
|
|
|
364 |
|
|
spinvector(mydir, midview.vdir, midview.vup, gd->ang); |
365 |
|
|
sum = 0.0; |
366 |
|
|
for (gs = all_srcs; gs != NULL; gs = gs->next) { |
367 |
|
|
p = posindex(gs->dir, mydir, midview.vup); |
368 |
|
|
if (p <= FTINY) |
369 |
|
|
continue; |
370 |
|
|
sum += pow(gs->lum/p,1.6) * pow(gs->dom,0.8); |
371 |
|
|
} |
372 |
|
|
if (sum <= FTINY) |
373 |
|
|
return(0.0); |
374 |
|
|
sum /= gd->indirect/PI; |
375 |
|
|
return(10*log10(0.478*sum)); |
376 |
|
|
} |
377 |
|
|
|
378 |
|
|
|
379 |
|
|
double |
380 |
greg |
1.2 |
guth_dgr(gd) /* compute Guth discomfort glare rating */ |
381 |
greg |
1.1 |
struct glare_dir *gd; |
382 |
|
|
{ |
383 |
|
|
#define q(w) (20.4*w+1.52*pow(w,.2)-.075) |
384 |
|
|
register struct glare_src *gs; |
385 |
greg |
1.7 |
FVECT mydir; |
386 |
greg |
1.1 |
double p; |
387 |
|
|
double sum; |
388 |
greg |
1.3 |
double wtot, brsum; |
389 |
greg |
1.1 |
int n; |
390 |
greg |
2.4 |
|
391 |
greg |
1.7 |
spinvector(mydir, midview.vdir, midview.vup, gd->ang); |
392 |
greg |
1.3 |
sum = wtot = brsum = 0.0; n = 0; |
393 |
greg |
1.1 |
for (gs = all_srcs; gs != NULL; gs = gs->next) { |
394 |
greg |
1.7 |
p = posindex(gs->dir, mydir, midview.vup); |
395 |
greg |
1.1 |
if (p <= FTINY) |
396 |
|
|
continue; |
397 |
|
|
sum += gs->lum * q(gs->dom) / p; |
398 |
greg |
1.3 |
brsum += gs->lum * gs->dom; |
399 |
|
|
wtot += gs->dom; |
400 |
greg |
1.1 |
n++; |
401 |
|
|
} |
402 |
|
|
if (n == 0) |
403 |
|
|
return(0.0); |
404 |
greg |
1.8 |
return( pow(.5*sum/pow((brsum+(5.-wtot)*gd->indirect/PI)/5.,.44), |
405 |
greg |
1.1 |
pow((double)n, -.0914) ) ); |
406 |
|
|
#undef q |
407 |
|
|
} |
408 |
greg |
2.4 |
|
409 |
|
|
|
410 |
greg |
1.1 |
extern double erf(), erfc(); |
411 |
greg |
2.4 |
|
412 |
greg |
1.1 |
#ifndef M_SQRT2 |
413 |
|
|
#define M_SQRT2 1.41421356237309504880 |
414 |
|
|
#endif |
415 |
greg |
2.4 |
|
416 |
greg |
1.1 |
#define norm_integral(z) (1.-.5*erfc((z)/M_SQRT2)) |
417 |
greg |
2.4 |
|
418 |
|
|
|
419 |
greg |
1.1 |
double |
420 |
greg |
1.2 |
guth_vcp(gd) /* compute Guth visual comfort probability */ |
421 |
greg |
1.1 |
struct glare_dir *gd; |
422 |
|
|
{ |
423 |
greg |
1.7 |
double dgr; |
424 |
greg |
2.4 |
|
425 |
greg |
1.7 |
dgr = guth_dgr(gd); |
426 |
|
|
if (dgr <= FTINY) |
427 |
|
|
return(100.0); |
428 |
|
|
return(100.*norm_integral(6.374-1.3227*log(dgr))); |
429 |
greg |
1.8 |
} |
430 |
greg |
2.4 |
|
431 |
|
|
|
432 |
greg |
1.8 |
double |
433 |
|
|
cie_cgi(gd) /* compute CIE Glare Index */ |
434 |
|
|
struct glare_dir *gd; |
435 |
|
|
{ |
436 |
|
|
register struct glare_src *gs; |
437 |
|
|
FVECT mydir; |
438 |
|
|
double dillum; |
439 |
|
|
double p; |
440 |
|
|
double sum; |
441 |
greg |
2.4 |
|
442 |
greg |
1.8 |
spinvector(mydir, midview.vdir, midview.vup, gd->ang); |
443 |
|
|
sum = 0.0; |
444 |
|
|
for (gs = all_srcs; gs != NULL; gs = gs->next) { |
445 |
|
|
p = posindex(gs->dir, mydir, midview.vup); |
446 |
|
|
if (p <= FTINY) |
447 |
|
|
continue; |
448 |
|
|
sum += gs->lum*gs->lum * gs->dom / (p*p); |
449 |
|
|
} |
450 |
|
|
if (sum <= FTINY) |
451 |
|
|
return(0.0); |
452 |
|
|
dillum = direct(gd); |
453 |
|
|
return(8.*log10(2.*sum*(1.+dillum/500.)/(dillum+gd->indirect))); |
454 |
greg |
2.4 |
} |
455 |
|
|
|
456 |
|
|
|
457 |
|
|
double |
458 |
|
|
ugr(gd) /* compute Unified Glare Rating */ |
459 |
|
|
struct glare_dir *gd; |
460 |
|
|
{ |
461 |
|
|
register struct glare_src *gs; |
462 |
|
|
FVECT mydir; |
463 |
|
|
double p; |
464 |
|
|
double sum; |
465 |
|
|
|
466 |
|
|
spinvector(mydir, midview.vdir, midview.vup, gd->ang); |
467 |
|
|
sum = 0.0; |
468 |
|
|
for (gs = all_srcs; gs != NULL; gs = gs->next) { |
469 |
|
|
p = posindex(gs->dir, mydir, midview.vup); |
470 |
|
|
if (p <= FTINY) |
471 |
|
|
continue; |
472 |
|
|
sum += gs->lum*gs->lum * gs->dom / (p*p); |
473 |
|
|
} |
474 |
|
|
if (sum <= FTINY) |
475 |
|
|
return(0.0); |
476 |
|
|
return(8.*log10(0.25*sum*PI/gd->indirect)); |
477 |
greg |
1.1 |
} |