| 1 |
#ifndef lint
|
| 2 |
static const char RCSid[] = "$Id: glarendx.c,v 2.12 2018/04/02 16:45:41 greg Exp $";
|
| 3 |
#endif
|
| 4 |
/*
|
| 5 |
* Compute Glare Index given by program name or -t option:
|
| 6 |
*
|
| 7 |
* dgi - Daylight Glare Index
|
| 8 |
* brs_gi - Building Research Station Glare Index (Petherbridge
|
| 9 |
* & Hopkinson)
|
| 10 |
* ugr - Unified Glare Rating System (Fischer)
|
| 11 |
* guth_dgr - Guth discomfort glare rating
|
| 12 |
* guth_vcp - Guth visual comfort probability
|
| 13 |
* cie_cgi - CIE Glare Index (1983, due to Einhorn)
|
| 14 |
* vert_dir - Direct vertical illuminance
|
| 15 |
* vert_ind - Indirect vertical illuminance (from input)
|
| 16 |
* vert_ill - Total vertical illuminance
|
| 17 |
*
|
| 18 |
* 12 April 1991 Greg Ward EPFL
|
| 19 |
* 19 April 1993 R. Compagnon EPFL (added dgi, brs_gi, ugr)
|
| 20 |
*/
|
| 21 |
|
| 22 |
#include <string.h>
|
| 23 |
|
| 24 |
#include "standard.h"
|
| 25 |
#include "view.h"
|
| 26 |
|
| 27 |
|
| 28 |
struct glare_src {
|
| 29 |
FVECT dir; /* source direction */
|
| 30 |
double dom; /* solid angle */
|
| 31 |
double lum; /* average luminance */
|
| 32 |
struct glare_src *next;
|
| 33 |
} *all_srcs = NULL;
|
| 34 |
|
| 35 |
struct glare_dir {
|
| 36 |
double ang; /* angle (in radians) */
|
| 37 |
double indirect; /* indirect illuminance */
|
| 38 |
struct glare_dir *next;
|
| 39 |
} *all_dirs = NULL;
|
| 40 |
|
| 41 |
typedef double gdfun(struct glare_dir *gd);
|
| 42 |
|
| 43 |
static gdfun dgi;
|
| 44 |
static gdfun brs_gi;
|
| 45 |
static gdfun ugr;
|
| 46 |
static gdfun guth_dgr;
|
| 47 |
static gdfun guth_vcp;
|
| 48 |
static gdfun cie_cgi;
|
| 49 |
static gdfun direct;
|
| 50 |
static gdfun indirect;
|
| 51 |
static gdfun total;
|
| 52 |
|
| 53 |
static gethfunc headline;
|
| 54 |
static void init(void);
|
| 55 |
static void read_input(void);
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| 56 |
static void print_values(gdfun *func);
|
| 57 |
static double posindex(FVECT sd, FVECT vd, FVECT vu);
|
| 58 |
|
| 59 |
|
| 60 |
struct named_func {
|
| 61 |
char *name;
|
| 62 |
gdfun *func;
|
| 63 |
char *descrip;
|
| 64 |
} all_funcs[] = {
|
| 65 |
{"dgi", dgi, "Daylight Glare Index"},
|
| 66 |
{"brs_gi", brs_gi, "BRS Glare Index"},
|
| 67 |
{"ugr", ugr, "Unified Glare Rating"},
|
| 68 |
{"guth_vcp", guth_vcp, "Guth Visual Comfort Probability"},
|
| 69 |
{"cie_cgi", cie_cgi, "CIE Glare Index (Einhorn)"},
|
| 70 |
{"guth_dgr", guth_dgr, "Guth Disability Glare Rating"},
|
| 71 |
{"vert_dir", direct, "Direct Vertical Illuminance"},
|
| 72 |
{"vert_ill", total, "Total Vertical Illuminance"},
|
| 73 |
{"vert_ind", indirect, "Indirect Vertical Illuminance"},
|
| 74 |
{NULL}
|
| 75 |
};
|
| 76 |
|
| 77 |
#define newp(type) (type *)malloc(sizeof(type))
|
| 78 |
|
| 79 |
char *progname;
|
| 80 |
int print_header = 1;
|
| 81 |
|
| 82 |
VIEW midview = STDVIEW;
|
| 83 |
|
| 84 |
int wrongformat = 0;
|
| 85 |
|
| 86 |
|
| 87 |
int
|
| 88 |
main(
|
| 89 |
int argc,
|
| 90 |
char *argv[]
|
| 91 |
)
|
| 92 |
{
|
| 93 |
struct named_func *funp;
|
| 94 |
char *progtail;
|
| 95 |
int i;
|
| 96 |
/* get program name */
|
| 97 |
progname = argv[0];
|
| 98 |
progtail = strrchr(progname, '/'); /* final component */
|
| 99 |
if (progtail == NULL)
|
| 100 |
progtail = progname;
|
| 101 |
else
|
| 102 |
progtail++;
|
| 103 |
/* get options */
|
| 104 |
for (i = 1; i < argc && argv[i][0] == '-'; i++)
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| 105 |
switch (argv[i][1]) {
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| 106 |
case 't':
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| 107 |
progtail = argv[++i];
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| 108 |
break;
|
| 109 |
case 'h':
|
| 110 |
print_header = 0;
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| 111 |
break;
|
| 112 |
default:
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| 113 |
goto userr;
|
| 114 |
}
|
| 115 |
if (i < argc-1)
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| 116 |
goto userr;
|
| 117 |
if (i == argc-1) /* open file */
|
| 118 |
if (freopen(argv[i], "r", stdin) == NULL) {
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| 119 |
perror(argv[i]);
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| 120 |
exit(1);
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| 121 |
}
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| 122 |
/* find and run calculation */
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| 123 |
for (funp = all_funcs; funp->name != NULL; funp++)
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| 124 |
if (!strcmp(funp->name, progtail)) {
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| 125 |
init();
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| 126 |
read_input();
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| 127 |
if (print_header) {
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| 128 |
printargs(i, argv, stdout);
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| 129 |
putchar('\n');
|
| 130 |
}
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| 131 |
print_values(funp->func);
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| 132 |
exit(0); /* we're done */
|
| 133 |
}
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| 134 |
/* invalid function */
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| 135 |
userr:
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| 136 |
fprintf(stderr, "Usage: %s -t type [-h] [input]\n", progname);
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| 137 |
fprintf(stderr, "\twhere 'type' is one of the following:\n");
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| 138 |
for (funp = all_funcs; funp->name != NULL; funp++)
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| 139 |
fprintf(stderr, "\t%12s\t%s\n", funp->name, funp->descrip);
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| 140 |
exit(1);
|
| 141 |
}
|
| 142 |
|
| 143 |
|
| 144 |
static int
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| 145 |
headline( /* get line from header */
|
| 146 |
char *s,
|
| 147 |
void *p
|
| 148 |
)
|
| 149 |
{
|
| 150 |
char fmt[MAXFMTLEN];
|
| 151 |
|
| 152 |
if (print_header) /* copy to output */
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| 153 |
fputs(s, stdout);
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| 154 |
if (isview(s))
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| 155 |
sscanview(&midview, s);
|
| 156 |
else if (isformat(s)) {
|
| 157 |
formatval(fmt, s);
|
| 158 |
wrongformat = strcmp(fmt, "ascii");
|
| 159 |
}
|
| 160 |
return(0);
|
| 161 |
}
|
| 162 |
|
| 163 |
|
| 164 |
static void
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| 165 |
init(void) /* initialize calculation */
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| 166 |
{
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| 167 |
/* read header */
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| 168 |
getheader(stdin, headline, NULL);
|
| 169 |
if (wrongformat) {
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| 170 |
fprintf(stderr, "%s: bad input format\n", progname);
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| 171 |
exit(1);
|
| 172 |
}
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| 173 |
/* set view */
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| 174 |
if (setview(&midview) != NULL) {
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| 175 |
fprintf(stderr, "%s: bad view information in input\n",
|
| 176 |
progname);
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| 177 |
exit(1);
|
| 178 |
}
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| 179 |
}
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| 180 |
|
| 181 |
|
| 182 |
static void
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| 183 |
read_input(void) /* read glare sources from stdin */
|
| 184 |
{
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| 185 |
#define S_SEARCH 0
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| 186 |
#define S_SOURCE 1
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| 187 |
#define S_DIREC 2
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| 188 |
int state = S_SEARCH;
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| 189 |
char buf[128];
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| 190 |
struct glare_src *gs;
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| 191 |
struct glare_dir *gd;
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| 192 |
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| 193 |
while (fgets(buf, sizeof(buf), stdin) != NULL)
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| 194 |
switch (state) {
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| 195 |
case S_SEARCH:
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| 196 |
if (!strcmp(buf, "BEGIN glare source\n"))
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| 197 |
state = S_SOURCE;
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| 198 |
else if (!strcmp(buf, "BEGIN indirect illuminance\n"))
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| 199 |
state = S_DIREC;
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| 200 |
break;
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| 201 |
case S_SOURCE:
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| 202 |
if (!strncmp(buf, "END", 3)) {
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| 203 |
state = S_SEARCH;
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| 204 |
break;
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| 205 |
}
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| 206 |
if ((gs = newp(struct glare_src)) == NULL)
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| 207 |
goto memerr;
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| 208 |
if (sscanf(buf, FVFORMAT, &gs->dir[0], &gs->dir[1],
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| 209 |
&gs->dir[2]) != 3 ||
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| 210 |
sscanf(sskip2(buf, 3), "%lf %lf",
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| 211 |
&gs->dom, &gs->lum) != 2)
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goto readerr;
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normalize(gs->dir);
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| 214 |
gs->next = all_srcs;
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| 215 |
all_srcs = gs;
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break;
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| 217 |
case S_DIREC:
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| 218 |
if (!strncmp(buf, "END", 3)) {
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state = S_SEARCH;
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break;
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}
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| 222 |
if ((gd = newp(struct glare_dir)) == NULL)
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goto memerr;
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| 224 |
if (sscanf(buf, "%lf %lf",
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| 225 |
&gd->ang, &gd->indirect) != 2)
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| 226 |
goto readerr;
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| 227 |
gd->ang *= PI/180.0; /* convert to radians */
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gd->next = all_dirs;
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all_dirs = gd;
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break;
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}
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return;
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memerr:
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perror(progname);
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exit(1);
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| 236 |
readerr:
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fprintf(stderr, "%s: read error on input\n", progname);
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exit(1);
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| 239 |
#undef S_SEARCH
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| 240 |
#undef S_SOURCE
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#undef S_DIREC
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| 242 |
}
|
| 243 |
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| 244 |
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| 245 |
static void
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| 246 |
print_values( /* print out calculations */
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| 247 |
gdfun *func
|
| 248 |
)
|
| 249 |
{
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| 250 |
struct glare_dir *gd;
|
| 251 |
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| 252 |
for (gd = all_dirs; gd != NULL; gd = gd->next)
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| 253 |
printf("%f\t%f\n", gd->ang*(180.0/PI), (*func)(gd));
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| 254 |
}
|
| 255 |
|
| 256 |
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| 257 |
static double
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| 258 |
direct( /* compute direct vertical illuminance */
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| 259 |
struct glare_dir *gd
|
| 260 |
)
|
| 261 |
{
|
| 262 |
FVECT mydir;
|
| 263 |
double d, dval;
|
| 264 |
struct glare_src *gs;
|
| 265 |
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| 266 |
spinvector(mydir, midview.vdir, midview.vup, gd->ang);
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| 267 |
dval = 0.0;
|
| 268 |
for (gs = all_srcs; gs != NULL; gs = gs->next) {
|
| 269 |
d = DOT(mydir,gs->dir);
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| 270 |
if (d > FTINY)
|
| 271 |
dval += d * gs->dom * gs->lum;
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| 272 |
}
|
| 273 |
return(dval);
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| 274 |
}
|
| 275 |
|
| 276 |
|
| 277 |
static double
|
| 278 |
indirect( /* return indirect vertical illuminance */
|
| 279 |
struct glare_dir *gd
|
| 280 |
)
|
| 281 |
{
|
| 282 |
return(gd->indirect);
|
| 283 |
}
|
| 284 |
|
| 285 |
|
| 286 |
static double
|
| 287 |
total( /* return total vertical illuminance */
|
| 288 |
struct glare_dir *gd
|
| 289 |
)
|
| 290 |
{
|
| 291 |
return(direct(gd)+gd->indirect);
|
| 292 |
}
|
| 293 |
|
| 294 |
|
| 295 |
/*
|
| 296 |
* posindex - compute glare position index from:
|
| 297 |
*
|
| 298 |
* Source Direction
|
| 299 |
* View Direction
|
| 300 |
* View Up Direction
|
| 301 |
*
|
| 302 |
* All vectors are assumed to be normalized.
|
| 303 |
* This function is an implementation of the method proposed by
|
| 304 |
* Robert Levin in his 1975 JIES article.
|
| 305 |
* This calculation presumes the view direction and up vectors perpendicular.
|
| 306 |
* We return a value less than zero for improper positions.
|
| 307 |
*/
|
| 308 |
|
| 309 |
static double
|
| 310 |
posindex( /* compute position index */
|
| 311 |
FVECT sd,
|
| 312 |
FVECT vd,
|
| 313 |
FVECT vu
|
| 314 |
)
|
| 315 |
{
|
| 316 |
double sigma, tau;
|
| 317 |
double d;
|
| 318 |
|
| 319 |
d = DOT(sd,vd);
|
| 320 |
if (d <= 0.0)
|
| 321 |
return(-1.0);
|
| 322 |
if (d >= 1.0)
|
| 323 |
return(1.0);
|
| 324 |
sigma = acos(d) * (180./PI);
|
| 325 |
d = fabs(DOT(sd,vu)/sqrt(1.0-d*d));
|
| 326 |
if (d >= 1.0)
|
| 327 |
tau = 0.0;
|
| 328 |
else
|
| 329 |
tau = acos(d) * (180./PI);
|
| 330 |
return( exp( sigma*( (35.2 - tau*.31889 - 1.22*exp(-.22222*tau))*1e-3
|
| 331 |
+ sigma*(21. + tau*(.26667 + tau*-.002963))*1e-5 )
|
| 332 |
) );
|
| 333 |
}
|
| 334 |
|
| 335 |
|
| 336 |
static double
|
| 337 |
dgi( /* compute Daylight Glare Index */
|
| 338 |
struct glare_dir *gd
|
| 339 |
)
|
| 340 |
{
|
| 341 |
struct glare_src *gs;
|
| 342 |
FVECT mydir,testdir[7],vhor;
|
| 343 |
double r,posn,omega,p[7],sum;
|
| 344 |
int i,n;
|
| 345 |
|
| 346 |
spinvector(mydir, midview.vdir, midview.vup, gd->ang);
|
| 347 |
sum = 0.0; n = 0;
|
| 348 |
for (gs = all_srcs; gs != NULL; gs = gs->next) {
|
| 349 |
|
| 350 |
/* compute 1/p^2 weighted solid angle of the source */
|
| 351 |
r = sqrt(1 - pow(1.-gs->dom/2./PI,2.));
|
| 352 |
fcross(vhor,gs->dir,midview.vup);
|
| 353 |
normalize(vhor);
|
| 354 |
VCOPY(testdir[0],gs->dir);
|
| 355 |
fvsum(testdir[1],gs->dir,vhor,r);
|
| 356 |
fvsum(testdir[2],gs->dir,vhor,0.5*r);
|
| 357 |
fvsum(testdir[5],testdir[2],midview.vup,-0.866*r);
|
| 358 |
fvsum(testdir[2],testdir[2],midview.vup,0.866*r);
|
| 359 |
fvsum(testdir[3],gs->dir,vhor,-r);
|
| 360 |
fvsum(testdir[4],gs->dir,vhor,-0.5*r);
|
| 361 |
fvsum(testdir[6],testdir[4],midview.vup,0.866*r);
|
| 362 |
fvsum(testdir[4],testdir[4],midview.vup,-0.866*r);
|
| 363 |
for (i = 0; i < 7; i++) {
|
| 364 |
normalize(testdir[i]);
|
| 365 |
posn = posindex(testdir[i],mydir,midview.vup);
|
| 366 |
if (posn <= FTINY)
|
| 367 |
p[i] = 0.0;
|
| 368 |
else
|
| 369 |
p[i] = 1./(posn*posn);
|
| 370 |
}
|
| 371 |
r = 1-gs->dom/2./PI;
|
| 372 |
omega = gs->dom*p[0];
|
| 373 |
omega += (r*PI*(1+1/r/r)-2*PI)*(-p[0]+(p[1]+p[2])*0.5);
|
| 374 |
omega += (2*PI-r*PI*(1+1/r/r))*(-p[0]-0.1667*(p[1]+p[3])
|
| 375 |
+0.3334*(p[2]+p[4]+p[5]+p[6]));
|
| 376 |
|
| 377 |
sum += pow(gs->lum,1.6) * pow(omega,0.8) /
|
| 378 |
(gd->indirect/PI + 0.07*sqrt(gs->dom)*gs->lum);
|
| 379 |
n++;
|
| 380 |
}
|
| 381 |
if (n == 0)
|
| 382 |
return(0.0);
|
| 383 |
return( 10*log10(0.478*sum) );
|
| 384 |
}
|
| 385 |
|
| 386 |
|
| 387 |
static double
|
| 388 |
brs_gi( /* compute BRS Glare Index */
|
| 389 |
struct glare_dir *gd
|
| 390 |
)
|
| 391 |
{
|
| 392 |
struct glare_src *gs;
|
| 393 |
FVECT mydir;
|
| 394 |
double p;
|
| 395 |
double sum;
|
| 396 |
|
| 397 |
spinvector(mydir, midview.vdir, midview.vup, gd->ang);
|
| 398 |
sum = 0.0;
|
| 399 |
for (gs = all_srcs; gs != NULL; gs = gs->next) {
|
| 400 |
p = posindex(gs->dir, mydir, midview.vup);
|
| 401 |
if (p <= FTINY)
|
| 402 |
continue;
|
| 403 |
sum += pow(gs->lum/p,1.6) * pow(gs->dom,0.8);
|
| 404 |
}
|
| 405 |
if (sum <= FTINY)
|
| 406 |
return(0.0);
|
| 407 |
sum /= gd->indirect/PI;
|
| 408 |
return(10*log10(0.478*sum));
|
| 409 |
}
|
| 410 |
|
| 411 |
|
| 412 |
static double
|
| 413 |
guth_dgr( /* compute Guth discomfort glare rating */
|
| 414 |
struct glare_dir *gd
|
| 415 |
)
|
| 416 |
{
|
| 417 |
#define q(w) (20.4*w+1.52*pow(w,.2)-.075)
|
| 418 |
struct glare_src *gs;
|
| 419 |
FVECT mydir;
|
| 420 |
double p;
|
| 421 |
double sum;
|
| 422 |
double wtot, brsum;
|
| 423 |
int n;
|
| 424 |
|
| 425 |
spinvector(mydir, midview.vdir, midview.vup, gd->ang);
|
| 426 |
sum = wtot = brsum = 0.0; n = 0;
|
| 427 |
for (gs = all_srcs; gs != NULL; gs = gs->next) {
|
| 428 |
p = posindex(gs->dir, mydir, midview.vup);
|
| 429 |
if (p <= FTINY)
|
| 430 |
continue;
|
| 431 |
sum += gs->lum * q(gs->dom) / p;
|
| 432 |
brsum += gs->lum * gs->dom;
|
| 433 |
wtot += gs->dom;
|
| 434 |
n++;
|
| 435 |
}
|
| 436 |
if (n == 0)
|
| 437 |
return(0.0);
|
| 438 |
return( pow(.5*sum/pow((brsum+(5.-wtot)*gd->indirect/PI)/5.,.44),
|
| 439 |
pow((double)n, -.0914) ) );
|
| 440 |
#undef q
|
| 441 |
}
|
| 442 |
|
| 443 |
|
| 444 |
#ifndef M_SQRT2
|
| 445 |
#define M_SQRT2 1.41421356237309504880
|
| 446 |
#endif
|
| 447 |
|
| 448 |
#define norm_integral(z) (1.-.5*erfc((z)/M_SQRT2))
|
| 449 |
|
| 450 |
|
| 451 |
static double
|
| 452 |
guth_vcp( /* compute Guth visual comfort probability */
|
| 453 |
struct glare_dir *gd
|
| 454 |
)
|
| 455 |
{
|
| 456 |
extern double erfc();
|
| 457 |
double dgr;
|
| 458 |
|
| 459 |
dgr = guth_dgr(gd);
|
| 460 |
if (dgr <= FTINY)
|
| 461 |
return(100.0);
|
| 462 |
return(100.*norm_integral(6.374-1.3227*log(dgr)));
|
| 463 |
}
|
| 464 |
|
| 465 |
|
| 466 |
static double
|
| 467 |
cie_cgi( /* compute CIE Glare Index */
|
| 468 |
struct glare_dir *gd
|
| 469 |
)
|
| 470 |
{
|
| 471 |
struct glare_src *gs;
|
| 472 |
FVECT mydir;
|
| 473 |
double dillum;
|
| 474 |
double p;
|
| 475 |
double sum;
|
| 476 |
|
| 477 |
spinvector(mydir, midview.vdir, midview.vup, gd->ang);
|
| 478 |
sum = 0.0;
|
| 479 |
for (gs = all_srcs; gs != NULL; gs = gs->next) {
|
| 480 |
p = posindex(gs->dir, mydir, midview.vup);
|
| 481 |
if (p <= FTINY)
|
| 482 |
continue;
|
| 483 |
sum += gs->lum*gs->lum * gs->dom / (p*p);
|
| 484 |
}
|
| 485 |
if (sum <= FTINY)
|
| 486 |
return(0.0);
|
| 487 |
dillum = direct(gd);
|
| 488 |
return(8.*log10(2.*sum*(1.+dillum/500.)/(dillum+gd->indirect)));
|
| 489 |
}
|
| 490 |
|
| 491 |
|
| 492 |
static double
|
| 493 |
ugr( /* compute Unified Glare Rating */
|
| 494 |
struct glare_dir *gd
|
| 495 |
)
|
| 496 |
{
|
| 497 |
struct glare_src *gs;
|
| 498 |
FVECT mydir;
|
| 499 |
double p;
|
| 500 |
double sum;
|
| 501 |
|
| 502 |
spinvector(mydir, midview.vdir, midview.vup, gd->ang);
|
| 503 |
sum = 0.0;
|
| 504 |
for (gs = all_srcs; gs != NULL; gs = gs->next) {
|
| 505 |
p = posindex(gs->dir, mydir, midview.vup);
|
| 506 |
if (p <= FTINY)
|
| 507 |
continue;
|
| 508 |
sum += gs->lum*gs->lum * gs->dom / (p*p);
|
| 509 |
}
|
| 510 |
if (sum <= FTINY)
|
| 511 |
return(0.0);
|
| 512 |
return(8.*log10(0.25*sum*PI/gd->indirect));
|
| 513 |
}
|
