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/* Copyright (c) 1991 Regents of the University of California */ |
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|
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#ifndef lint |
2 |
< |
static char SCCSid[] = "$SunId$ LBL"; |
2 |
> |
static const char RCSid[] = "$Id$"; |
3 |
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#endif |
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|
4 |
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/* |
5 |
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* Compute Glare Index given by program name: |
5 |
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* Compute Glare Index given by program name or -t option: |
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* |
7 |
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* dgi - Daylight Glare Index |
8 |
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* brs_gi - Building Research Station Glare Index (Petherbridge |
9 |
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* & Hopkinson) |
10 |
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* ugr - Unified Glare Rating System (Fischer) |
11 |
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* guth_dgr - Guth discomfort glare rating |
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* guth_vcp - Guth visual comfort probability |
13 |
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* cie_cgi - CIE Glare Index (1983, due to Einhorn) |
14 |
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* vert_dir - Direct vertical illuminance |
15 |
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* vert_ind - Indirect vertical illuminance (from input) |
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* vert_ill - Total vertical illuminance |
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* |
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* 12 April 1991 Greg Ward EPFL |
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* 19 April 1993 R. Compagnon EPFL (added dgi, brs_gi, ugr) |
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*/ |
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|
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#include <string.h> |
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|
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#include "standard.h" |
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#include "paths.h" |
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#include "view.h" |
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|
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extern double erfc(); |
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|
21 |
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double posindex(); |
22 |
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int headline(); |
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|
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double direct(), guth_dgr(), guth_vcp(); |
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|
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struct named_func { |
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char *name; |
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double (*func)(); |
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} all_funcs[] = { |
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{"direct", direct}, |
31 |
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{"guth_dgr", guth_dgr}, |
32 |
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{"guth_vcp", guth_vcp}, |
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{NULL} |
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}; |
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|
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struct glare_src { |
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FVECT dir; /* source direction */ |
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double dom; /* solid angle */ |
39 |
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struct glare_dir *next; |
40 |
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} *all_dirs = NULL; |
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|
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typedef double gdfun(struct glare_dir *gd); |
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|
44 |
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static gdfun dgi; |
45 |
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static gdfun brs_gi; |
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static gdfun ugr; |
47 |
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static gdfun guth_dgr; |
48 |
+ |
static gdfun guth_vcp; |
49 |
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static gdfun cie_cgi; |
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static gdfun direct; |
51 |
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static gdfun indirect; |
52 |
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static gdfun total; |
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|
54 |
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static gethfunc headline; |
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static void init(void); |
56 |
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static void read_input(void); |
57 |
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static void print_values(gdfun *func); |
58 |
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static double posindex(FVECT sd, FVECT vd, FVECT vu); |
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|
60 |
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|
61 |
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struct named_func { |
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char *name; |
63 |
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gdfun *func; |
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char *descrip; |
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} all_funcs[] = { |
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{"dgi", dgi, "Daylight Glare Index"}, |
67 |
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{"brs_gi", brs_gi, "BRS Glare Index"}, |
68 |
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{"ugr", ugr, "Unified Glare Rating"}, |
69 |
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{"guth_vcp", guth_vcp, "Guth Visual Comfort Probability"}, |
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{"cie_cgi", cie_cgi, "CIE Glare Index (Einhorn)"}, |
71 |
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{"guth_dgr", guth_dgr, "Guth Disability Glare Rating"}, |
72 |
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{"vert_dir", direct, "Direct Vertical Illuminance"}, |
73 |
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{"vert_ill", total, "Total Vertical Illuminance"}, |
74 |
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{"vert_ind", indirect, "Indirect Vertical Illuminance"}, |
75 |
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{NULL} |
76 |
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}; |
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|
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#define newp(type) (type *)malloc(sizeof(type)) |
79 |
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|
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char *progname; |
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|
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VIEW midview = STDVIEW; |
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|
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int wrongformat = 0; |
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|
87 |
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main(argc, argv) |
88 |
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int argc; |
89 |
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char *argv[]; |
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|
88 |
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int |
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main( |
90 |
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int argc, |
91 |
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char *argv[] |
92 |
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) |
93 |
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{ |
61 |
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extern char *rindex(); |
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struct named_func *funp; |
63 |
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char *progtail; |
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int i; |
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/* get program name */ |
97 |
< |
progname = argv[0]; |
67 |
< |
progtail = rindex(progname, '/'); /* final component */ |
68 |
< |
if (progtail == NULL) |
69 |
< |
progtail = progname; |
70 |
< |
else |
71 |
< |
progtail++; |
97 |
> |
progname = fixargv0(argv[0]); |
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/* get options */ |
99 |
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for (i = 1; i < argc && argv[i][0] == '-'; i++) |
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switch (argv[i][1]) { |
101 |
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case 't': |
102 |
< |
progtail = argv[++i]; |
102 |
> |
progname = argv[++i]; |
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break; |
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case 'h': |
105 |
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print_header = 0; |
114 |
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perror(argv[i]); |
115 |
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exit(1); |
116 |
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} |
117 |
< |
/* read header */ |
92 |
< |
getheader(stdin, headline); |
93 |
< |
if (print_header) { /* add to header */ |
94 |
< |
printargs(i, argv, stdout); |
95 |
< |
putchar('\n'); |
96 |
< |
} |
97 |
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/* set view */ |
98 |
< |
if (setview(&midview) != NULL) { |
99 |
< |
fprintf(stderr, "%s: bad view information in input\n"); |
100 |
< |
exit(1); |
101 |
< |
} |
102 |
< |
/* get findglare data */ |
103 |
< |
read_input(); |
104 |
< |
/* find calculation */ |
117 |
> |
/* find and run calculation */ |
118 |
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for (funp = all_funcs; funp->name != NULL; funp++) |
119 |
< |
if (!strcmp(funp->name, progtail)) { |
119 |
> |
if (!strcmp(funp->name, progname)) { |
120 |
> |
init(); |
121 |
> |
read_input(); |
122 |
> |
if (print_header) { |
123 |
> |
printargs(i, argv, stdout); |
124 |
> |
putchar('\n'); |
125 |
> |
} |
126 |
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print_values(funp->func); |
127 |
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exit(0); /* we're done */ |
128 |
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} |
129 |
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/* invalid function */ |
111 |
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fprintf(stderr, "%s: unknown function!\n", progtail); |
112 |
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exit(1); |
130 |
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userr: |
131 |
< |
fprintf(stderr, "Usage: %s [-t type][-h] [input]\n", progname); |
131 |
> |
fprintf(stderr, "Usage: %s -t type [-h] [input]\n", progname); |
132 |
> |
fprintf(stderr, "\twhere 'type' is one of the following:\n"); |
133 |
> |
for (funp = all_funcs; funp->name != NULL; funp++) |
134 |
> |
fprintf(stderr, "\t%12s\t%s\n", funp->name, funp->descrip); |
135 |
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exit(1); |
136 |
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} |
137 |
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|
138 |
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|
139 |
< |
headline(s) /* get line from header */ |
140 |
< |
char *s; |
139 |
> |
static int |
140 |
> |
headline( /* get line from header */ |
141 |
> |
char *s, |
142 |
> |
void *p |
143 |
> |
) |
144 |
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{ |
145 |
+ |
char fmt[MAXFMTLEN]; |
146 |
+ |
|
147 |
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if (print_header) /* copy to output */ |
148 |
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fputs(s, stdout); |
149 |
< |
if (!strncmp(s, VIEWSTR, VIEWSTRL)) |
150 |
< |
sscanview(&midview, s+VIEWSTRL); |
149 |
> |
if (isview(s)) |
150 |
> |
sscanview(&midview, s); |
151 |
> |
else if (isformat(s)) { |
152 |
> |
formatval(fmt, s); |
153 |
> |
wrongformat = strcmp(fmt, "ascii"); |
154 |
> |
} |
155 |
> |
return(0); |
156 |
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} |
157 |
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|
158 |
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|
159 |
< |
read_input() /* read glare sources from stdin */ |
159 |
> |
static void |
160 |
> |
init(void) /* initialize calculation */ |
161 |
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{ |
162 |
+ |
char *err; |
163 |
+ |
/* read header */ |
164 |
+ |
getheader(stdin, headline, NULL); |
165 |
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if (wrongformat) { |
166 |
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fprintf(stderr, "%s: bad input format\n", progname); |
167 |
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exit(1); |
168 |
+ |
} |
169 |
+ |
/* set view */ |
170 |
+ |
if ((err = setview(&midview)) != NULL) { |
171 |
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fprintf(stderr, "%s: %s\n", |
172 |
+ |
progname, err); |
173 |
+ |
exit(1); |
174 |
+ |
} |
175 |
+ |
if (fabs(DOT(midview.vdir, midview.vup)) > 1e-4) { |
176 |
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fprintf(stderr, |
177 |
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"%s: Input view direction not perpendicular to up vector\n", |
178 |
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progname); |
179 |
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exit(1); |
180 |
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} |
181 |
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} |
182 |
+ |
|
183 |
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|
184 |
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static void |
185 |
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read_input(void) /* read glare sources from stdin */ |
186 |
+ |
{ |
187 |
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#define S_SEARCH 0 |
188 |
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#define S_SOURCE 1 |
189 |
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#define S_DIREC 2 |
190 |
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int state = S_SEARCH; |
191 |
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char buf[128]; |
192 |
< |
register struct glare_src *gs; |
193 |
< |
register struct glare_dir *gd; |
192 |
> |
struct glare_src *gs; |
193 |
> |
struct glare_dir *gd; |
194 |
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|
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while (fgets(buf, sizeof(buf), stdin) != NULL) |
196 |
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switch (state) { |
207 |
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} |
208 |
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if ((gs = newp(struct glare_src)) == NULL) |
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goto memerr; |
210 |
< |
if (sscanf(buf, "%lf %lf %lf %lf %lf", |
211 |
< |
&gs->dir[0], &gs->dir[1], &gs->dir[2], |
212 |
< |
&gs->dom, &gs->lum) != 5) |
210 |
> |
if (sscanf(buf, FVFORMAT, &gs->dir[0], &gs->dir[1], |
211 |
> |
&gs->dir[2]) != 3 || |
212 |
> |
sscanf(sskip2(buf, 3), "%lf %lf", |
213 |
> |
&gs->dom, &gs->lum) != 2) |
214 |
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goto readerr; |
215 |
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normalize(gs->dir); |
216 |
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gs->next = all_srcs; |
244 |
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} |
245 |
|
|
246 |
|
|
247 |
< |
print_values(funp) /* print out calculations */ |
248 |
< |
double (*funp)(); |
247 |
> |
static void |
248 |
> |
print_values( /* print out calculations */ |
249 |
> |
gdfun *func |
250 |
> |
) |
251 |
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{ |
252 |
< |
register struct glare_dir *gd; |
252 |
> |
struct glare_dir *gd; |
253 |
|
|
254 |
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for (gd = all_dirs; gd != NULL; gd = gd->next) |
255 |
< |
printf("%f\t%f\n", gd->ang*(180.0/PI), (*funp)(gd)); |
255 |
> |
printf("%f\t%f\n", gd->ang*(180.0/PI), (*func)(gd)); |
256 |
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} |
257 |
|
|
258 |
|
|
259 |
< |
double |
260 |
< |
direct(gd) /* compute direct illuminance */ |
261 |
< |
struct glare_dir *gd; |
259 |
> |
static double |
260 |
> |
direct( /* compute direct vertical illuminance */ |
261 |
> |
struct glare_dir *gd |
262 |
> |
) |
263 |
|
{ |
264 |
|
FVECT mydir; |
265 |
|
double d, dval; |
266 |
< |
register struct glare_src *gs; |
266 |
> |
struct glare_src *gs; |
267 |
|
|
268 |
|
spinvector(mydir, midview.vdir, midview.vup, gd->ang); |
269 |
|
dval = 0.0; |
276 |
|
} |
277 |
|
|
278 |
|
|
279 |
+ |
static double |
280 |
+ |
indirect( /* return indirect vertical illuminance */ |
281 |
+ |
struct glare_dir *gd |
282 |
+ |
) |
283 |
+ |
{ |
284 |
+ |
return(gd->indirect); |
285 |
+ |
} |
286 |
+ |
|
287 |
+ |
|
288 |
+ |
static double |
289 |
+ |
total( /* return total vertical illuminance */ |
290 |
+ |
struct glare_dir *gd |
291 |
+ |
) |
292 |
+ |
{ |
293 |
+ |
return(direct(gd)+gd->indirect); |
294 |
+ |
} |
295 |
+ |
|
296 |
+ |
|
297 |
|
/* |
298 |
|
* posindex - compute glare position index from: |
299 |
|
* |
304 |
|
* All vectors are assumed to be normalized. |
305 |
|
* This function is an implementation of the method proposed by |
306 |
|
* Robert Levin in his 1975 JIES article. |
307 |
+ |
* This calculation presumes the view direction and up vectors perpendicular. |
308 |
|
* We return a value less than zero for improper positions. |
309 |
|
*/ |
310 |
|
|
311 |
< |
double |
312 |
< |
posindex(sd, vd, vu) /* compute position index */ |
313 |
< |
FVECT sd, vd, vu; |
311 |
> |
static double |
312 |
> |
posindex( /* compute position index */ |
313 |
> |
FVECT sd, |
314 |
> |
FVECT vd, |
315 |
> |
FVECT vu |
316 |
> |
) |
317 |
|
{ |
318 |
|
double sigma, tau; |
319 |
|
double d; |
321 |
|
d = DOT(sd,vd); |
322 |
|
if (d <= 0.0) |
323 |
|
return(-1.0); |
324 |
+ |
if (d >= 1.0-FTINY) |
325 |
+ |
return(1.0); |
326 |
|
sigma = acos(d) * (180./PI); |
327 |
< |
tau = acos(DOT(sd,vu)/sqrt(1.0-d*d)) * (180./PI); |
327 |
> |
d = fabs(DOT(sd,vu)/sqrt(1.0-d*d)); |
328 |
> |
tau = Acos(d) * (180./PI); |
329 |
|
return( exp( sigma*( (35.2 - tau*.31889 - 1.22*exp(-.22222*tau))*1e-3 |
330 |
|
+ sigma*(21. + tau*(.26667 + tau*-.002963))*1e-5 ) |
331 |
|
) ); |
332 |
|
} |
333 |
|
|
334 |
|
|
335 |
< |
double |
336 |
< |
guth_dgr(gd) /* compute Guth discomfort glare rating */ |
337 |
< |
struct glare_dir *gd; |
335 |
> |
static double |
336 |
> |
dgi( /* compute Daylight Glare Index */ |
337 |
> |
struct glare_dir *gd |
338 |
> |
) |
339 |
|
{ |
340 |
+ |
struct glare_src *gs; |
341 |
+ |
FVECT mydir,testdir[7],vhor; |
342 |
+ |
double r,posn,omega,p[7],sum; |
343 |
+ |
int i; |
344 |
+ |
|
345 |
+ |
spinvector(mydir, midview.vdir, midview.vup, gd->ang); |
346 |
+ |
sum = 0.0; |
347 |
+ |
for (gs = all_srcs; gs != NULL; gs = gs->next) { |
348 |
+ |
|
349 |
+ |
/* compute 1/p^2 weighted solid angle of the source */ |
350 |
+ |
r = 1. - gs->dom*(.5/PI); |
351 |
+ |
r = sqrt(1. - r*r); |
352 |
+ |
fcross(vhor,gs->dir,midview.vup); |
353 |
+ |
if (normalize(vhor) == 0.) |
354 |
+ |
continue; |
355 |
+ |
VCOPY(testdir[0],gs->dir); |
356 |
+ |
fvsum(testdir[1],gs->dir,vhor,r); |
357 |
+ |
fvsum(testdir[2],gs->dir,vhor,0.5*r); |
358 |
+ |
fvsum(testdir[5],testdir[2],midview.vup,-0.866*r); |
359 |
+ |
fvsum(testdir[2],testdir[2],midview.vup,0.866*r); |
360 |
+ |
fvsum(testdir[3],gs->dir,vhor,-r); |
361 |
+ |
fvsum(testdir[4],gs->dir,vhor,-0.5*r); |
362 |
+ |
fvsum(testdir[6],testdir[4],midview.vup,0.866*r); |
363 |
+ |
fvsum(testdir[4],testdir[4],midview.vup,-0.866*r); |
364 |
+ |
for (i = 0; i < 7; i++) { |
365 |
+ |
p[i] = 0.0; |
366 |
+ |
if (normalize(testdir[i]) == 0.) |
367 |
+ |
continue; |
368 |
+ |
posn = posindex(testdir[i],mydir,midview.vup); |
369 |
+ |
if (posn > FTINY) |
370 |
+ |
p[i] = 1./(posn*posn); |
371 |
+ |
} |
372 |
+ |
r = 1. - gs->dom*(.5/PI); |
373 |
+ |
omega = gs->dom*p[0]; |
374 |
+ |
omega += (r*PI*(1.+1./(r*r))-2.*PI)*(-p[0]+(p[1]+p[2])*0.5); |
375 |
+ |
omega += (2.*PI-r*PI*(1.+1./(r*r)))*(-p[0]-0.1667*(p[1]+p[3]) |
376 |
+ |
+0.3334*(p[2]+p[4]+p[5]+p[6])); |
377 |
+ |
if (omega <= 0.) |
378 |
+ |
continue; |
379 |
+ |
sum += pow(gs->lum,1.6) * pow(omega,0.8) / |
380 |
+ |
(gd->indirect*(1./PI) + 0.07*sqrt(gs->dom)*gs->lum); |
381 |
+ |
} |
382 |
+ |
if (sum <= FTINY) |
383 |
+ |
return(0.0); |
384 |
+ |
return( 10.*log10(0.478*sum) ); |
385 |
+ |
} |
386 |
+ |
|
387 |
+ |
|
388 |
+ |
static double |
389 |
+ |
brs_gi( /* compute BRS Glare Index */ |
390 |
+ |
struct glare_dir *gd |
391 |
+ |
) |
392 |
+ |
{ |
393 |
+ |
struct glare_src *gs; |
394 |
+ |
FVECT mydir; |
395 |
+ |
double p; |
396 |
+ |
double sum; |
397 |
+ |
|
398 |
+ |
spinvector(mydir, midview.vdir, midview.vup, gd->ang); |
399 |
+ |
sum = 0.0; |
400 |
+ |
for (gs = all_srcs; gs != NULL; gs = gs->next) { |
401 |
+ |
p = posindex(gs->dir, mydir, midview.vup); |
402 |
+ |
if (p <= FTINY) |
403 |
+ |
continue; |
404 |
+ |
sum += pow(gs->lum/p,1.6) * pow(gs->dom,0.8); |
405 |
+ |
} |
406 |
+ |
if (sum <= FTINY) |
407 |
+ |
return(0.0); |
408 |
+ |
sum *= PI/gd->indirect; |
409 |
+ |
return(10*log10(0.478*sum)); |
410 |
+ |
} |
411 |
+ |
|
412 |
+ |
|
413 |
+ |
static double |
414 |
+ |
guth_dgr( /* compute Guth discomfort glare rating */ |
415 |
+ |
struct glare_dir *gd |
416 |
+ |
) |
417 |
+ |
{ |
418 |
|
#define q(w) (20.4*w+1.52*pow(w,.2)-.075) |
419 |
< |
register struct glare_src *gs; |
419 |
> |
struct glare_src *gs; |
420 |
> |
FVECT mydir; |
421 |
|
double p; |
422 |
|
double sum; |
423 |
+ |
double wtot, brsum; |
424 |
|
int n; |
425 |
|
|
426 |
< |
sum = 0.0; n = 0; |
426 |
> |
spinvector(mydir, midview.vdir, midview.vup, gd->ang); |
427 |
> |
sum = wtot = brsum = 0.0; n = 0; |
428 |
|
for (gs = all_srcs; gs != NULL; gs = gs->next) { |
429 |
< |
p = posindex(gs->dir, midview.vdir, midview.vup); |
429 |
> |
p = posindex(gs->dir, mydir, midview.vup); |
430 |
|
if (p <= FTINY) |
431 |
|
continue; |
432 |
|
sum += gs->lum * q(gs->dom) / p; |
433 |
+ |
brsum += gs->lum * gs->dom; |
434 |
+ |
wtot += gs->dom; |
435 |
|
n++; |
436 |
|
} |
437 |
|
if (n == 0) |
438 |
|
return(0.0); |
439 |
< |
else |
271 |
< |
return( pow( |
272 |
< |
.5*sum/pow(direct(gd)+gd->indirect,.44), |
439 |
> |
return( pow(.5*sum/pow((brsum+(5.-wtot)*gd->indirect/PI)/5.,.44), |
440 |
|
pow((double)n, -.0914) ) ); |
441 |
|
#undef q |
442 |
|
} |
443 |
|
|
444 |
|
|
278 |
– |
extern double erf(), erfc(); |
279 |
– |
|
445 |
|
#ifndef M_SQRT2 |
446 |
|
#define M_SQRT2 1.41421356237309504880 |
447 |
|
#endif |
449 |
|
#define norm_integral(z) (1.-.5*erfc((z)/M_SQRT2)) |
450 |
|
|
451 |
|
|
452 |
< |
double |
453 |
< |
guth_vcp(gd) /* compute Guth visual comfort probability */ |
454 |
< |
struct glare_dir *gd; |
452 |
> |
static double |
453 |
> |
guth_vcp( /* compute Guth visual comfort probability */ |
454 |
> |
struct glare_dir *gd |
455 |
> |
) |
456 |
|
{ |
457 |
< |
return(100.*norm_integral(-6.374+1.3227*log(guth_dgr(gd)))); |
457 |
> |
extern double erfc(); |
458 |
> |
double dgr; |
459 |
> |
|
460 |
> |
dgr = guth_dgr(gd); |
461 |
> |
if (dgr <= FTINY) |
462 |
> |
return(100.0); |
463 |
> |
return(100.*norm_integral(6.374-1.3227*log(dgr))); |
464 |
> |
} |
465 |
> |
|
466 |
> |
|
467 |
> |
static double |
468 |
> |
cie_cgi( /* compute CIE Glare Index */ |
469 |
> |
struct glare_dir *gd |
470 |
> |
) |
471 |
> |
{ |
472 |
> |
struct glare_src *gs; |
473 |
> |
FVECT mydir; |
474 |
> |
double dillum; |
475 |
> |
double p; |
476 |
> |
double sum; |
477 |
> |
|
478 |
> |
spinvector(mydir, midview.vdir, midview.vup, gd->ang); |
479 |
> |
sum = 0.0; |
480 |
> |
for (gs = all_srcs; gs != NULL; gs = gs->next) { |
481 |
> |
p = posindex(gs->dir, mydir, midview.vup); |
482 |
> |
if (p <= FTINY) |
483 |
> |
continue; |
484 |
> |
sum += gs->lum*gs->lum * gs->dom / (p*p); |
485 |
> |
} |
486 |
> |
if (sum <= FTINY) |
487 |
> |
return(0.0); |
488 |
> |
dillum = direct(gd); |
489 |
> |
return(8.*log10(2.*sum*(1.+dillum/500.)/(dillum+gd->indirect))); |
490 |
> |
} |
491 |
> |
|
492 |
> |
|
493 |
> |
static double |
494 |
> |
ugr( /* compute Unified Glare Rating */ |
495 |
> |
struct glare_dir *gd |
496 |
> |
) |
497 |
> |
{ |
498 |
> |
struct glare_src *gs; |
499 |
> |
FVECT mydir; |
500 |
> |
double p; |
501 |
> |
double sum; |
502 |
> |
|
503 |
> |
spinvector(mydir, midview.vdir, midview.vup, gd->ang); |
504 |
> |
sum = 0.0; |
505 |
> |
for (gs = all_srcs; gs != NULL; gs = gs->next) { |
506 |
> |
p = posindex(gs->dir, mydir, midview.vup); |
507 |
> |
if (p <= FTINY) |
508 |
> |
continue; |
509 |
> |
sum += gs->lum*gs->lum * gs->dom / (p*p); |
510 |
> |
} |
511 |
> |
if (sum <= FTINY) |
512 |
> |
return(0.0); |
513 |
> |
return(8.*log10(0.25*sum*PI/gd->indirect)); |
514 |
|
} |