| 1 |
– |
/* Copyright (c) 1991 Regents of the University of California */ |
| 2 |
– |
|
| 1 |
|
#ifndef lint |
| 2 |
< |
static char SCCSid[] = "$SunId$ LBL"; |
| 2 |
> |
static const char RCSid[] = "$Id$"; |
| 3 |
|
#endif |
| 6 |
– |
|
| 4 |
|
/* |
| 5 |
< |
* Routines to do the actual calcultion and output for mkillum |
| 5 |
> |
* Routines to do the actual calculation for mkillum |
| 6 |
|
*/ |
| 7 |
|
|
| 8 |
< |
#include "mkillum.h" |
| 8 |
> |
#include <string.h> |
| 9 |
|
|
| 10 |
+ |
#include "mkillum.h" |
| 11 |
|
#include "face.h" |
| 14 |
– |
|
| 12 |
|
#include "cone.h" |
| 16 |
– |
|
| 13 |
|
#include "random.h" |
| 14 |
|
|
| 15 |
|
|
| 16 |
< |
printobj(mod, obj) /* print out an object */ |
| 17 |
< |
char *mod; |
| 18 |
< |
register OBJREC *obj; |
| 19 |
< |
{ |
| 20 |
< |
register int i; |
| 16 |
> |
int o_default(FUN_ARGLIST); |
| 17 |
> |
int o_face(FUN_ARGLIST); |
| 18 |
> |
int o_sphere(FUN_ARGLIST); |
| 19 |
> |
int o_ring(FUN_ARGLIST); |
| 20 |
> |
void raysamp(float res[3], FVECT org, FVECT dir, struct rtproc *rt); |
| 21 |
> |
void rayflush(struct rtproc *rt); |
| 22 |
> |
void mkaxes(FVECT u, FVECT v, FVECT n); |
| 23 |
> |
void rounddir(FVECT dv, double alt, double azi); |
| 24 |
> |
void flatdir(FVECT dv, double alt, double azi); |
| 25 |
|
|
| 26 |
– |
printf("\n%s %s %s", mod, ofun[obj->otype].funame, obj->oname); |
| 27 |
– |
printf("\n%d", obj->oargs.nsargs); |
| 28 |
– |
for (i = 0; i < obj->oargs.nsargs; i++) |
| 29 |
– |
printf(" %s", obj->oargs.sarg[i]); |
| 30 |
– |
#ifdef IARGS |
| 31 |
– |
printf("\n%d", obj->oargs.niargs); |
| 32 |
– |
for (i = 0; i < obj->oargs.niargs; i++) |
| 33 |
– |
printf(" %d", obj->oargs.iarg[i]); |
| 34 |
– |
#else |
| 35 |
– |
printf("\n0"); |
| 36 |
– |
#endif |
| 37 |
– |
printf("\n%d", obj->oargs.nfargs); |
| 38 |
– |
for (i = 0; i < obj->oargs.nfargs; i++) { |
| 39 |
– |
if (i%3 == 0) |
| 40 |
– |
putchar('\n'); |
| 41 |
– |
printf(" %18.12g", obj->oargs.farg[i]); |
| 42 |
– |
} |
| 43 |
– |
putchar('\n'); |
| 44 |
– |
} |
| 26 |
|
|
| 27 |
< |
|
| 28 |
< |
o_default(ob, il, rt, nm) /* default illum action */ |
| 29 |
< |
OBJREC *ob; |
| 30 |
< |
struct illum_args *il; |
| 31 |
< |
struct rtproc *rt; |
| 32 |
< |
char *nm; |
| 27 |
> |
int /* XXX type conflict with otypes.h */ |
| 28 |
> |
o_default( /* default illum action */ |
| 29 |
> |
OBJREC *ob, |
| 30 |
> |
struct illum_args *il, |
| 31 |
> |
struct rtproc *rt, |
| 32 |
> |
char *nm |
| 33 |
> |
) |
| 34 |
|
{ |
| 35 |
|
sprintf(errmsg, "(%s): cannot make illum for %s \"%s\"", |
| 36 |
|
nm, ofun[ob->otype].funame, ob->oname); |
| 37 |
|
error(WARNING, errmsg); |
| 38 |
< |
if (!(il->flags & IL_LIGHT)) |
| 39 |
< |
printobj(il->altname, ob); |
| 38 |
> |
printobj(il->altmat, ob); |
| 39 |
> |
return(1); |
| 40 |
|
} |
| 41 |
|
|
| 42 |
|
|
| 43 |
< |
o_face(ob, il, rt, nm) /* make an illum face */ |
| 44 |
< |
OBJREC *ob; |
| 45 |
< |
struct illum_args *il; |
| 46 |
< |
struct rtproc *rt; |
| 47 |
< |
char *nm; |
| 43 |
> |
int |
| 44 |
> |
o_face( /* make an illum face */ |
| 45 |
> |
OBJREC *ob, |
| 46 |
> |
struct illum_args *il, |
| 47 |
> |
struct rtproc *rt, |
| 48 |
> |
char *nm |
| 49 |
> |
) |
| 50 |
|
{ |
| 51 |
+ |
#define MAXMISS (5*n*il->nsamps) |
| 52 |
+ |
int dim[3]; |
| 53 |
+ |
int n, nalt, nazi, h; |
| 54 |
+ |
float *distarr; |
| 55 |
+ |
double sp[2], r1, r2; |
| 56 |
+ |
FVECT dn, org, dir; |
| 57 |
+ |
FVECT u, v; |
| 58 |
+ |
double ur[2], vr[2]; |
| 59 |
+ |
int nmisses; |
| 60 |
+ |
register FACE *fa; |
| 61 |
+ |
register int i, j; |
| 62 |
+ |
/* get/check arguments */ |
| 63 |
+ |
fa = getface(ob); |
| 64 |
+ |
if (fa->area == 0.0) { |
| 65 |
+ |
freeface(ob); |
| 66 |
+ |
return(o_default(ob, il, rt, nm)); |
| 67 |
+ |
} |
| 68 |
+ |
/* set up sampling */ |
| 69 |
+ |
if (il->sampdens <= 0) |
| 70 |
+ |
nalt = nazi = 1; |
| 71 |
+ |
else { |
| 72 |
+ |
n = PI * il->sampdens; |
| 73 |
+ |
nalt = sqrt(n/PI) + .5; |
| 74 |
+ |
nazi = PI*nalt + .5; |
| 75 |
+ |
} |
| 76 |
+ |
n = nalt*nazi; |
| 77 |
+ |
distarr = (float *)calloc(n, 3*sizeof(float)); |
| 78 |
+ |
if (distarr == NULL) |
| 79 |
+ |
error(SYSTEM, "out of memory in o_face"); |
| 80 |
+ |
/* take first edge longer than sqrt(area) */ |
| 81 |
+ |
for (j = fa->nv-1, i = 0; i < fa->nv; j = i++) { |
| 82 |
+ |
u[0] = VERTEX(fa,i)[0] - VERTEX(fa,j)[0]; |
| 83 |
+ |
u[1] = VERTEX(fa,i)[1] - VERTEX(fa,j)[1]; |
| 84 |
+ |
u[2] = VERTEX(fa,i)[2] - VERTEX(fa,j)[2]; |
| 85 |
+ |
if ((r1 = DOT(u,u)) >= fa->area-FTINY) |
| 86 |
+ |
break; |
| 87 |
+ |
} |
| 88 |
+ |
if (i < fa->nv) { /* got one! -- let's align our axes */ |
| 89 |
+ |
r2 = 1.0/sqrt(r1); |
| 90 |
+ |
u[0] *= r2; u[1] *= r2; u[2] *= r2; |
| 91 |
+ |
fcross(v, fa->norm, u); |
| 92 |
+ |
} else /* oh well, we'll just have to wing it */ |
| 93 |
+ |
mkaxes(u, v, fa->norm); |
| 94 |
+ |
/* now, find limits in (u,v) coordinates */ |
| 95 |
+ |
ur[0] = vr[0] = FHUGE; |
| 96 |
+ |
ur[1] = vr[1] = -FHUGE; |
| 97 |
+ |
for (i = 0; i < fa->nv; i++) { |
| 98 |
+ |
r1 = DOT(VERTEX(fa,i),u); |
| 99 |
+ |
if (r1 < ur[0]) ur[0] = r1; |
| 100 |
+ |
if (r1 > ur[1]) ur[1] = r1; |
| 101 |
+ |
r2 = DOT(VERTEX(fa,i),v); |
| 102 |
+ |
if (r2 < vr[0]) vr[0] = r2; |
| 103 |
+ |
if (r2 > vr[1]) vr[1] = r2; |
| 104 |
+ |
} |
| 105 |
+ |
dim[0] = random(); |
| 106 |
+ |
/* sample polygon */ |
| 107 |
+ |
nmisses = 0; |
| 108 |
+ |
for (dim[1] = 0; dim[1] < nalt; dim[1]++) |
| 109 |
+ |
for (dim[2] = 0; dim[2] < nazi; dim[2]++) |
| 110 |
+ |
for (i = 0; i < il->nsamps; i++) { |
| 111 |
+ |
/* random direction */ |
| 112 |
+ |
h = ilhash(dim, 3) + i; |
| 113 |
+ |
multisamp(sp, 2, urand(h)); |
| 114 |
+ |
r1 = (dim[1] + sp[0])/nalt; |
| 115 |
+ |
r2 = (dim[2] + sp[1] - .5)/nazi; |
| 116 |
+ |
flatdir(dn, r1, r2); |
| 117 |
+ |
for (j = 0; j < 3; j++) |
| 118 |
+ |
dir[j] = -dn[0]*u[j] - dn[1]*v[j] - dn[2]*fa->norm[j]; |
| 119 |
+ |
/* random location */ |
| 120 |
+ |
do { |
| 121 |
+ |
multisamp(sp, 2, urand(h+4862+nmisses)); |
| 122 |
+ |
r1 = ur[0] + (ur[1]-ur[0]) * sp[0]; |
| 123 |
+ |
r2 = vr[0] + (vr[1]-vr[0]) * sp[1]; |
| 124 |
+ |
for (j = 0; j < 3; j++) |
| 125 |
+ |
org[j] = r1*u[j] + r2*v[j] |
| 126 |
+ |
+ fa->offset*fa->norm[j]; |
| 127 |
+ |
} while (!inface(org, fa) && nmisses++ < MAXMISS); |
| 128 |
+ |
if (nmisses > MAXMISS) { |
| 129 |
+ |
objerror(ob, WARNING, "bad aspect"); |
| 130 |
+ |
rt->nrays = 0; |
| 131 |
+ |
freeface(ob); |
| 132 |
+ |
free((void *)distarr); |
| 133 |
+ |
return(o_default(ob, il, rt, nm)); |
| 134 |
+ |
} |
| 135 |
+ |
for (j = 0; j < 3; j++) |
| 136 |
+ |
org[j] += .001*fa->norm[j]; |
| 137 |
+ |
/* send sample */ |
| 138 |
+ |
raysamp(distarr+3*(dim[1]*nazi+dim[2]), org, dir, rt); |
| 139 |
+ |
} |
| 140 |
+ |
rayflush(rt); |
| 141 |
+ |
/* write out the face and its distribution */ |
| 142 |
+ |
if (average(il, distarr, nalt*nazi)) { |
| 143 |
+ |
if (il->sampdens > 0) |
| 144 |
+ |
flatout(il, distarr, nalt, nazi, u, v, fa->norm); |
| 145 |
+ |
illumout(il, ob); |
| 146 |
+ |
} else |
| 147 |
+ |
printobj(il->altmat, ob); |
| 148 |
+ |
/* clean up */ |
| 149 |
+ |
freeface(ob); |
| 150 |
+ |
free((void *)distarr); |
| 151 |
+ |
#undef MAXMISS |
| 152 |
|
} |
| 153 |
|
|
| 154 |
|
|
| 155 |
< |
o_sphere(ob, il, rt, nm) /* make an illum sphere */ |
| 156 |
< |
OBJREC *ob; |
| 157 |
< |
struct illum_args *il; |
| 158 |
< |
struct rtproc *rt; |
| 159 |
< |
char *nm; |
| 155 |
> |
int |
| 156 |
> |
o_sphere( /* make an illum sphere */ |
| 157 |
> |
register OBJREC *ob, |
| 158 |
> |
struct illum_args *il, |
| 159 |
> |
struct rtproc *rt, |
| 160 |
> |
char *nm |
| 161 |
> |
) |
| 162 |
|
{ |
| 163 |
< |
int dim[4]; |
| 163 |
> |
int dim[3]; |
| 164 |
|
int n, nalt, nazi; |
| 165 |
|
float *distarr; |
| 166 |
< |
double r1, r2; |
| 167 |
< |
FVECT pos, dir; |
| 166 |
> |
double sp[4], r1, r2, r3; |
| 167 |
> |
FVECT org, dir; |
| 168 |
|
FVECT u, v; |
| 169 |
|
register int i, j; |
| 170 |
|
/* check arguments */ |
| 171 |
|
if (ob->oargs.nfargs != 4) |
| 172 |
|
objerror(ob, USER, "bad # of arguments"); |
| 173 |
|
/* set up sampling */ |
| 174 |
< |
n = 4.*PI * il->sampdens; |
| 175 |
< |
nalt = sqrt(n/PI) + .5; |
| 176 |
< |
nazi = PI*nalt + .5; |
| 174 |
> |
if (il->sampdens <= 0) |
| 175 |
> |
nalt = nazi = 1; |
| 176 |
> |
else { |
| 177 |
> |
n = 4.*PI * il->sampdens; |
| 178 |
> |
nalt = sqrt(2./PI*n) + .5; |
| 179 |
> |
nazi = PI/2.*nalt + .5; |
| 180 |
> |
} |
| 181 |
|
n = nalt*nazi; |
| 182 |
|
distarr = (float *)calloc(n, 3*sizeof(float)); |
| 183 |
|
if (distarr == NULL) |
| 187 |
|
for (dim[1] = 0; dim[1] < nalt; dim[1]++) |
| 188 |
|
for (dim[2] = 0; dim[2] < nazi; dim[2]++) |
| 189 |
|
for (i = 0; i < il->nsamps; i++) { |
| 190 |
+ |
/* next sample point */ |
| 191 |
+ |
multisamp(sp, 4, urand(ilhash(dim,3)+i)); |
| 192 |
|
/* random direction */ |
| 193 |
< |
dim[3] = 1; |
| 194 |
< |
r1 = (dim[1]+urand(urind(ilhash(dim,4),i)))/nalt; |
| 102 |
< |
dim[3] = 2; |
| 103 |
< |
r2 = (dim[2]+urand(urind(ilhash(dim,4),i)))/nalt; |
| 193 |
> |
r1 = (dim[1] + sp[0])/nalt; |
| 194 |
> |
r2 = (dim[2] + sp[1] - .5)/nazi; |
| 195 |
|
rounddir(dir, r1, r2); |
| 196 |
|
/* random location */ |
| 197 |
|
mkaxes(u, v, dir); /* yuck! */ |
| 198 |
< |
dim[3] = 3; |
| 199 |
< |
r1 = sqrt(urand(urind(ilhash(dim,4),i))); |
| 200 |
< |
dim[3] = 4; |
| 201 |
< |
r2 = 2.*PI*urand(urind(ilhash(dim,4),i)); |
| 202 |
< |
for (j = 0; j < 3; j++) |
| 203 |
< |
org[j] = obj->oargs.farg[j] + obj->oargs.farg[3] * |
| 204 |
< |
( r1*cos(r2)*u[j] + r1*sin(r2)*v[j] |
| 205 |
< |
- sqrt(1.01-r1*r1)*dir[j] ); |
| 206 |
< |
|
| 198 |
> |
r3 = sqrt(sp[2]); |
| 199 |
> |
r2 = 2.*PI*sp[3]; |
| 200 |
> |
r1 = r3*ob->oargs.farg[3]*cos(r2); |
| 201 |
> |
r2 = r3*ob->oargs.farg[3]*sin(r2); |
| 202 |
> |
r3 = ob->oargs.farg[3]*sqrt(1.01-r3*r3); |
| 203 |
> |
for (j = 0; j < 3; j++) { |
| 204 |
> |
org[j] = ob->oargs.farg[j] + r1*u[j] + r2*v[j] + |
| 205 |
> |
r3*dir[j]; |
| 206 |
> |
dir[j] = -dir[j]; |
| 207 |
> |
} |
| 208 |
|
/* send sample */ |
| 209 |
< |
raysamp(distarr+dim[1]*nazi+dim[2], org, dir, rt); |
| 209 |
> |
raysamp(distarr+3*(dim[1]*nazi+dim[2]), org, dir, rt); |
| 210 |
|
} |
| 211 |
|
rayflush(rt); |
| 212 |
< |
/* write out distribution */ |
| 213 |
< |
rounddist(distarr, nalt, nazi, il, ob); |
| 212 |
> |
/* write out the sphere and its distribution */ |
| 213 |
> |
if (average(il, distarr, nalt*nazi)) { |
| 214 |
> |
if (il->sampdens > 0) |
| 215 |
> |
roundout(il, distarr, nalt, nazi); |
| 216 |
> |
else |
| 217 |
> |
objerror(ob, WARNING, "diffuse distribution"); |
| 218 |
> |
illumout(il, ob); |
| 219 |
> |
} else |
| 220 |
> |
printobj(il->altmat, ob); |
| 221 |
|
/* clean up */ |
| 222 |
< |
free((char *)distarr); |
| 222 |
> |
free((void *)distarr); |
| 223 |
> |
return(1); |
| 224 |
|
} |
| 225 |
|
|
| 226 |
|
|
| 227 |
< |
o_ring(ob, il, rt, nm) /* make an illum ring */ |
| 228 |
< |
OBJREC *ob; |
| 229 |
< |
struct illum_args *il; |
| 230 |
< |
struct rtproc *rt; |
| 231 |
< |
char *nm; |
| 227 |
> |
int |
| 228 |
> |
o_ring( /* make an illum ring */ |
| 229 |
> |
OBJREC *ob, |
| 230 |
> |
struct illum_args *il, |
| 231 |
> |
struct rtproc *rt, |
| 232 |
> |
char *nm |
| 233 |
> |
) |
| 234 |
|
{ |
| 235 |
+ |
int dim[3]; |
| 236 |
+ |
int n, nalt, nazi; |
| 237 |
+ |
float *distarr; |
| 238 |
+ |
double sp[4], r1, r2, r3; |
| 239 |
+ |
FVECT dn, org, dir; |
| 240 |
+ |
FVECT u, v; |
| 241 |
+ |
register CONE *co; |
| 242 |
+ |
register int i, j; |
| 243 |
+ |
/* get/check arguments */ |
| 244 |
+ |
co = getcone(ob, 0); |
| 245 |
+ |
/* set up sampling */ |
| 246 |
+ |
if (il->sampdens <= 0) |
| 247 |
+ |
nalt = nazi = 1; |
| 248 |
+ |
else { |
| 249 |
+ |
n = PI * il->sampdens; |
| 250 |
+ |
nalt = sqrt(n/PI) + .5; |
| 251 |
+ |
nazi = PI*nalt + .5; |
| 252 |
+ |
} |
| 253 |
+ |
n = nalt*nazi; |
| 254 |
+ |
distarr = (float *)calloc(n, 3*sizeof(float)); |
| 255 |
+ |
if (distarr == NULL) |
| 256 |
+ |
error(SYSTEM, "out of memory in o_ring"); |
| 257 |
+ |
mkaxes(u, v, co->ad); |
| 258 |
+ |
dim[0] = random(); |
| 259 |
+ |
/* sample disk */ |
| 260 |
+ |
for (dim[1] = 0; dim[1] < nalt; dim[1]++) |
| 261 |
+ |
for (dim[2] = 0; dim[2] < nazi; dim[2]++) |
| 262 |
+ |
for (i = 0; i < il->nsamps; i++) { |
| 263 |
+ |
/* next sample point */ |
| 264 |
+ |
multisamp(sp, 4, urand(ilhash(dim,3)+i)); |
| 265 |
+ |
/* random direction */ |
| 266 |
+ |
r1 = (dim[1] + sp[0])/nalt; |
| 267 |
+ |
r2 = (dim[2] + sp[1] - .5)/nazi; |
| 268 |
+ |
flatdir(dn, r1, r2); |
| 269 |
+ |
for (j = 0; j < 3; j++) |
| 270 |
+ |
dir[j] = -dn[0]*u[j] - dn[1]*v[j] - dn[2]*co->ad[j]; |
| 271 |
+ |
/* random location */ |
| 272 |
+ |
r3 = sqrt(CO_R0(co)*CO_R0(co) + |
| 273 |
+ |
sp[2]*(CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co))); |
| 274 |
+ |
r2 = 2.*PI*sp[3]; |
| 275 |
+ |
r1 = r3*cos(r2); |
| 276 |
+ |
r2 = r3*sin(r2); |
| 277 |
+ |
for (j = 0; j < 3; j++) |
| 278 |
+ |
org[j] = CO_P0(co)[j] + r1*u[j] + r2*v[j] + |
| 279 |
+ |
.001*co->ad[j]; |
| 280 |
+ |
|
| 281 |
+ |
/* send sample */ |
| 282 |
+ |
raysamp(distarr+3*(dim[1]*nazi+dim[2]), org, dir, rt); |
| 283 |
+ |
} |
| 284 |
+ |
rayflush(rt); |
| 285 |
+ |
/* write out the ring and its distribution */ |
| 286 |
+ |
if (average(il, distarr, nalt*nazi)) { |
| 287 |
+ |
if (il->sampdens > 0) |
| 288 |
+ |
flatout(il, distarr, nalt, nazi, u, v, co->ad); |
| 289 |
+ |
illumout(il, ob); |
| 290 |
+ |
} else |
| 291 |
+ |
printobj(il->altmat, ob); |
| 292 |
+ |
/* clean up */ |
| 293 |
+ |
freecone(ob); |
| 294 |
+ |
free((void *)distarr); |
| 295 |
+ |
return(1); |
| 296 |
|
} |
| 297 |
|
|
| 298 |
|
|
| 299 |
< |
raysamp(res, org, dir, rt) /* compute a ray sample */ |
| 300 |
< |
float res[3]; |
| 301 |
< |
FVECT org, dir; |
| 302 |
< |
register struct rtproc *rt; |
| 299 |
> |
void |
| 300 |
> |
raysamp( /* compute a ray sample */ |
| 301 |
> |
float res[3], |
| 302 |
> |
FVECT org, |
| 303 |
> |
FVECT dir, |
| 304 |
> |
register struct rtproc *rt |
| 305 |
> |
) |
| 306 |
|
{ |
| 307 |
|
register float *fp; |
| 308 |
|
|
| 315 |
|
} |
| 316 |
|
|
| 317 |
|
|
| 318 |
< |
rayflush(rt) /* flush buffered rays */ |
| 319 |
< |
register struct rtproc *rt; |
| 318 |
> |
void |
| 319 |
> |
rayflush( /* flush buffered rays */ |
| 320 |
> |
register struct rtproc *rt |
| 321 |
> |
) |
| 322 |
|
{ |
| 323 |
|
register int i; |
| 324 |
|
|
| 325 |
|
if (rt->nrays <= 0) |
| 326 |
|
return; |
| 327 |
< |
i = 6*rt->nrays + 3; |
| 328 |
< |
rt->buf[i++] = 0.; rt->buf[i++] = 0.; rt->buf[i] = 0.; |
| 329 |
< |
if ( process(rt->pd, (char *)rt->buf, (char *)rt->buf, |
| 330 |
< |
3*sizeof(float)*rt->nrays, |
| 327 |
> |
memset(rt->buf+6*rt->nrays, '\0', 6*sizeof(float)); |
| 328 |
> |
errno = 0; |
| 329 |
> |
if ( process(&(rt->pd), (char *)rt->buf, (char *)rt->buf, |
| 330 |
> |
3*sizeof(float)*(rt->nrays+1), |
| 331 |
|
6*sizeof(float)*(rt->nrays+1)) < |
| 332 |
< |
3*sizeof(float)*rt->nrays ) |
| 332 |
> |
3*sizeof(float)*(rt->nrays+1) ) |
| 333 |
|
error(SYSTEM, "error reading from rtrace process"); |
| 334 |
|
i = rt->nrays; |
| 335 |
|
while (i--) { |
| 338 |
|
rt->dest[i][2] += rt->buf[3*i+2]; |
| 339 |
|
} |
| 340 |
|
rt->nrays = 0; |
| 341 |
+ |
} |
| 342 |
+ |
|
| 343 |
+ |
|
| 344 |
+ |
void |
| 345 |
+ |
mkaxes( /* compute u and v to go with n */ |
| 346 |
+ |
FVECT u, |
| 347 |
+ |
FVECT v, |
| 348 |
+ |
FVECT n |
| 349 |
+ |
) |
| 350 |
+ |
{ |
| 351 |
+ |
register int i; |
| 352 |
+ |
|
| 353 |
+ |
v[0] = v[1] = v[2] = 0.0; |
| 354 |
+ |
for (i = 0; i < 3; i++) |
| 355 |
+ |
if (n[i] < 0.6 && n[i] > -0.6) |
| 356 |
+ |
break; |
| 357 |
+ |
v[i] = 1.0; |
| 358 |
+ |
fcross(u, v, n); |
| 359 |
+ |
normalize(u); |
| 360 |
+ |
fcross(v, n, u); |
| 361 |
+ |
} |
| 362 |
+ |
|
| 363 |
+ |
|
| 364 |
+ |
void |
| 365 |
+ |
rounddir( /* compute uniform spherical direction */ |
| 366 |
+ |
register FVECT dv, |
| 367 |
+ |
double alt, |
| 368 |
+ |
double azi |
| 369 |
+ |
) |
| 370 |
+ |
{ |
| 371 |
+ |
double d1, d2; |
| 372 |
+ |
|
| 373 |
+ |
dv[2] = 1. - 2.*alt; |
| 374 |
+ |
d1 = sqrt(1. - dv[2]*dv[2]); |
| 375 |
+ |
d2 = 2.*PI * azi; |
| 376 |
+ |
dv[0] = d1*cos(d2); |
| 377 |
+ |
dv[1] = d1*sin(d2); |
| 378 |
+ |
} |
| 379 |
+ |
|
| 380 |
+ |
|
| 381 |
+ |
void |
| 382 |
+ |
flatdir( /* compute uniform hemispherical direction */ |
| 383 |
+ |
register FVECT dv, |
| 384 |
+ |
double alt, |
| 385 |
+ |
double azi |
| 386 |
+ |
) |
| 387 |
+ |
{ |
| 388 |
+ |
double d1, d2; |
| 389 |
+ |
|
| 390 |
+ |
d1 = sqrt(alt); |
| 391 |
+ |
d2 = 2.*PI * azi; |
| 392 |
+ |
dv[0] = d1*cos(d2); |
| 393 |
+ |
dv[1] = d1*sin(d2); |
| 394 |
+ |
dv[2] = sqrt(1. - alt); |
| 395 |
|
} |
