26 |
|
#define ANG2R(r) (int)((r)*((1<<16)/M_PI)) |
27 |
|
|
28 |
|
typedef struct { |
29 |
< |
float vsum; /* BSDF sum */ |
29 |
> |
float vsum; /* DSF sum */ |
30 |
|
unsigned short nval; /* number of values in sum */ |
31 |
|
unsigned short crad; /* radius (coded angle) */ |
32 |
|
} GRIDVAL; /* grid value */ |
33 |
|
|
34 |
|
typedef struct { |
35 |
< |
float bsdf; /* lobe value at peak */ |
35 |
> |
float peak; /* lobe value at peak */ |
36 |
|
unsigned short crad; /* radius (coded angle) */ |
37 |
|
unsigned char gx, gy; /* grid position */ |
38 |
|
} RBFVAL; /* radial basis function value */ |
42 |
|
FVECT invec; /* incident vector direction */ |
43 |
|
int nrbf; /* number of RBFs */ |
44 |
|
RBFVAL rbfa[1]; /* RBF array (extends struct) */ |
45 |
< |
} RBFLIST; /* RBF representation of BSDF @ 1 incidence */ |
45 |
> |
} RBFLIST; /* RBF representation of DSF @ 1 incidence */ |
46 |
|
|
47 |
|
/* our loaded grid for this incident angle */ |
48 |
|
static double theta_in_deg, phi_in_deg; |
49 |
< |
static GRIDVAL bsdf_grid[GRIDRES][GRIDRES]; |
49 |
> |
static GRIDVAL dsf_grid[GRIDRES][GRIDRES]; |
50 |
|
|
51 |
< |
/* processed incident BSDF measurements */ |
52 |
< |
static RBFLIST *bsdf_list = NULL; |
51 |
> |
/* processed incident DSF measurements */ |
52 |
> |
static RBFLIST *dsf_list = NULL; |
53 |
|
|
54 |
|
/* Compute outgoing vector from grid position */ |
55 |
|
static void |
80 |
|
pos[1] = (int)(sq[1]*GRIDRES); |
81 |
|
} |
82 |
|
|
83 |
< |
/* Evaluate RBF for BSDF at the given normalized outgoing direction */ |
83 |
> |
/* Evaluate RBF for DSF at the given normalized outgoing direction */ |
84 |
|
static double |
85 |
|
eval_rbfrep(const RBFLIST *rp, const FVECT outvec) |
86 |
|
{ |
96 |
|
sig2 = R2ANG(rbfp->crad); |
97 |
|
sig2 = (DOT(odir,outvec) - 1.) / (sig2*sig2); |
98 |
|
if (sig2 > -19.) |
99 |
< |
res += rbfp->bsdf * exp(sig2); |
99 |
> |
res += rbfp->peak * exp(sig2); |
100 |
|
} |
101 |
|
return(res); |
102 |
|
} |
105 |
|
static RBFLIST * |
106 |
|
make_rbfrep(void) |
107 |
|
{ |
108 |
< |
int niter = 4; |
108 |
> |
int niter = 6; |
109 |
|
int nn; |
110 |
|
RBFLIST *newnode; |
111 |
|
int i, j; |
113 |
|
nn = 0; /* count selected bins */ |
114 |
|
for (i = 0; i < GRIDRES; i++) |
115 |
|
for (j = 0; j < GRIDRES; j++) |
116 |
< |
nn += (bsdf_grid[i][j].nval > 0); |
116 |
> |
nn += (dsf_grid[i][j].nval > 0); |
117 |
|
/* allocate RBF array */ |
118 |
|
newnode = (RBFLIST *)malloc(sizeof(RBFLIST) + sizeof(RBFVAL)*(nn-1)); |
119 |
|
if (newnode == NULL) { |
129 |
|
nn = 0; /* fill RBF array */ |
130 |
|
for (i = 0; i < GRIDRES; i++) |
131 |
|
for (j = 0; j < GRIDRES; j++) |
132 |
< |
if (bsdf_grid[i][j].nval) { |
133 |
< |
newnode->rbfa[nn].bsdf = |
134 |
< |
bsdf_grid[i][j].vsum /= |
135 |
< |
(double)bsdf_grid[i][j].nval; |
136 |
< |
bsdf_grid[i][j].nval = 1; |
137 |
< |
newnode->rbfa[nn].crad = RSCA*bsdf_grid[i][j].crad + .5; |
132 |
> |
if (dsf_grid[i][j].nval) { |
133 |
> |
newnode->rbfa[nn].peak = |
134 |
> |
dsf_grid[i][j].vsum /= |
135 |
> |
(double)dsf_grid[i][j].nval; |
136 |
> |
dsf_grid[i][j].nval = 1; |
137 |
> |
newnode->rbfa[nn].crad = RSCA*dsf_grid[i][j].crad + .5; |
138 |
|
newnode->rbfa[nn].gx = i; |
139 |
|
newnode->rbfa[nn].gy = j; |
140 |
|
++nn; |
141 |
|
} |
142 |
|
/* iterate for better convergence */ |
143 |
|
while (niter--) { |
144 |
+ |
double dsum = .0, dsum2 = .0; |
145 |
|
nn = 0; |
146 |
|
for (i = 0; i < GRIDRES; i++) |
147 |
|
for (j = 0; j < GRIDRES; j++) |
148 |
< |
if (bsdf_grid[i][j].nval) { |
148 |
> |
if (dsf_grid[i][j].nval) { |
149 |
|
FVECT odir; |
150 |
+ |
/* double corr; */ |
151 |
|
vec_from_pos(odir, i, j); |
152 |
< |
newnode->rbfa[nn++].bsdf *= |
153 |
< |
bsdf_grid[i][j].vsum / |
152 |
> |
newnode->rbfa[nn++].peak *= /* corr = */ |
153 |
> |
dsf_grid[i][j].vsum / |
154 |
|
eval_rbfrep(newnode, odir); |
155 |
+ |
/* |
156 |
+ |
dsum += corr - 1.; |
157 |
+ |
dsum2 += (corr-1.)*(corr-1.); |
158 |
+ |
*/ |
159 |
|
} |
160 |
+ |
/* |
161 |
+ |
fprintf(stderr, "Avg., RMS error: %.1f%% %.1f%%\n", |
162 |
+ |
100.*dsum/(double)nn, |
163 |
+ |
100.*sqrt(dsum2/(double)nn)); |
164 |
+ |
*/ |
165 |
|
} |
166 |
< |
newnode->next = bsdf_list; |
167 |
< |
return(bsdf_list = newnode); |
166 |
> |
newnode->next = dsf_list; |
167 |
> |
return(dsf_list = newnode); |
168 |
|
} |
169 |
|
|
170 |
|
/* Load a set of measurements corresponding to a particular incident angle */ |
182 |
|
fputs(": cannot open\n", stderr); |
183 |
|
return(0); |
184 |
|
} |
185 |
< |
memset(bsdf_grid, 0, sizeof(bsdf_grid)); |
185 |
> |
memset(dsf_grid, 0, sizeof(dsf_grid)); |
186 |
|
/* read header information */ |
187 |
|
while ((c = getc(fp)) == '#' || c == EOF) { |
188 |
|
if (fgets(buf, sizeof(buf), fp) == NULL) { |
223 |
|
ovec[1] = sin(M_PI/180.*phi_out) * ovec[2]; |
224 |
|
ovec[2] = sqrt(1. - ovec[2]*ovec[2]); |
225 |
|
|
226 |
< |
if (inp_is_DSF) |
227 |
< |
val /= ovec[2]; /* convert from DSF to BSDF */ |
226 |
> |
if (!inp_is_DSF) |
227 |
> |
val *= ovec[2]; /* convert from BSDF to DSF */ |
228 |
|
|
229 |
|
pos_from_vec(pos, ovec); |
230 |
|
|
231 |
< |
bsdf_grid[pos[0]][pos[1]].vsum += val; |
232 |
< |
bsdf_grid[pos[0]][pos[1]].nval++; |
231 |
> |
dsf_grid[pos[0]][pos[1]].vsum += val; |
232 |
> |
dsf_grid[pos[0]][pos[1]].nval++; |
233 |
|
} |
234 |
|
n = 0; |
235 |
|
while ((c = getc(fp)) != EOF) |
247 |
|
static void |
248 |
|
compute_radii(void) |
249 |
|
{ |
250 |
< |
unsigned short fill_grid[GRIDRES][GRIDRES]; |
250 |
> |
unsigned int fill_grid[GRIDRES][GRIDRES]; |
251 |
> |
unsigned short fill_cnt[GRIDRES][GRIDRES]; |
252 |
|
FVECT ovec0, ovec1; |
253 |
|
double ang2, lastang2; |
242 |
– |
int r2, lastr2; |
254 |
|
int r, i, j, jn, ii, jj, inear, jnear; |
255 |
|
|
256 |
|
r = GRIDRES/2; /* proceed in zig-zag */ |
257 |
|
for (i = 0; i < GRIDRES; i++) |
258 |
|
for (jn = 0; jn < GRIDRES; jn++) { |
259 |
|
j = (i&1) ? jn : GRIDRES-1-jn; |
260 |
< |
if (bsdf_grid[i][j].nval) /* find empty grid pos. */ |
260 |
> |
if (dsf_grid[i][j].nval) /* find empty grid pos. */ |
261 |
|
continue; |
262 |
|
vec_from_pos(ovec0, i, j); |
263 |
|
inear = jnear = -1; /* find nearest non-empty */ |
268 |
|
for (jj = j-r; jj <= j+r; jj++) { |
269 |
|
if (jj < 0) continue; |
270 |
|
if (jj >= GRIDRES) break; |
271 |
< |
if (!bsdf_grid[ii][jj].nval) |
271 |
> |
if (!dsf_grid[ii][jj].nval) |
272 |
|
continue; |
273 |
|
vec_from_pos(ovec1, ii, jj); |
274 |
|
ang2 = 2. - 2.*DOT(ovec0,ovec1); |
284 |
|
} |
285 |
|
ang2 = sqrt(lastang2); |
286 |
|
r = ANG2R(ang2); /* record if > previous */ |
287 |
< |
if (r > bsdf_grid[inear][jnear].crad) |
288 |
< |
bsdf_grid[inear][jnear].crad = r; |
287 |
> |
if (r > dsf_grid[inear][jnear].crad) |
288 |
> |
dsf_grid[inear][jnear].crad = r; |
289 |
|
/* next search radius */ |
290 |
|
r = ang2*(2.*GRIDRES/M_PI) + 1; |
291 |
|
} |
292 |
< |
/* fill in neighbors */ |
292 |
> |
/* blur radii over hemisphere */ |
293 |
|
memset(fill_grid, 0, sizeof(fill_grid)); |
294 |
+ |
memset(fill_cnt, 0, sizeof(fill_cnt)); |
295 |
|
for (i = 0; i < GRIDRES; i++) |
296 |
|
for (j = 0; j < GRIDRES; j++) { |
297 |
< |
if (!bsdf_grid[i][j].nval) |
298 |
< |
continue; /* no value -- skip */ |
299 |
< |
if (bsdf_grid[i][j].crad) |
288 |
< |
continue; /* has distance already */ |
289 |
< |
r = GRIDRES/20; |
290 |
< |
lastr2 = 2*r*r + 1; |
297 |
> |
if (!dsf_grid[i][j].crad) |
298 |
> |
continue; /* missing distance */ |
299 |
> |
r = R2ANG(dsf_grid[i][j].crad)*(2.*RSCA*GRIDRES/M_PI); |
300 |
|
for (ii = i-r; ii <= i+r; ii++) { |
301 |
|
if (ii < 0) continue; |
302 |
|
if (ii >= GRIDRES) break; |
303 |
|
for (jj = j-r; jj <= j+r; jj++) { |
304 |
|
if (jj < 0) continue; |
305 |
|
if (jj >= GRIDRES) break; |
306 |
< |
if (!bsdf_grid[ii][jj].crad) |
306 |
> |
if ((ii-i)*(ii-i) + (jj-j)*(jj-j) > r*r) |
307 |
|
continue; |
308 |
< |
/* OK to use approx. closest */ |
309 |
< |
r2 = (ii-i)*(ii-i) + (jj-j)*(jj-j); |
301 |
< |
if (r2 >= lastr2) |
302 |
< |
continue; |
303 |
< |
fill_grid[i][j] = bsdf_grid[ii][jj].crad; |
304 |
< |
lastr2 = r2; |
308 |
> |
fill_grid[ii][jj] += dsf_grid[i][j].crad; |
309 |
> |
fill_cnt[ii][jj]++; |
310 |
|
} |
311 |
|
} |
312 |
|
} |
313 |
< |
/* copy back filled entries */ |
313 |
> |
/* copy back averaged radii */ |
314 |
|
for (i = 0; i < GRIDRES; i++) |
315 |
|
for (j = 0; j < GRIDRES; j++) |
316 |
< |
if (fill_grid[i][j]) |
317 |
< |
bsdf_grid[i][j].crad = fill_grid[i][j]; |
316 |
> |
if (fill_cnt[i][j]) |
317 |
> |
dsf_grid[i][j].crad = fill_grid[i][j]/fill_cnt[i][j]; |
318 |
|
} |
319 |
|
|
320 |
|
/* Cull points for more uniform distribution */ |
327 |
|
/* simple greedy algorithm */ |
328 |
|
for (i = 0; i < GRIDRES; i++) |
329 |
|
for (j = 0; j < GRIDRES; j++) { |
330 |
< |
if (!bsdf_grid[i][j].nval) |
330 |
> |
if (!dsf_grid[i][j].nval) |
331 |
|
continue; |
332 |
< |
if (!bsdf_grid[i][j].crad) |
332 |
> |
if (!dsf_grid[i][j].crad) |
333 |
|
continue; /* shouldn't happen */ |
334 |
|
vec_from_pos(ovec0, i, j); |
335 |
< |
maxang = 2.*R2ANG(bsdf_grid[i][j].crad); |
335 |
> |
maxang = 2.*R2ANG(dsf_grid[i][j].crad); |
336 |
|
if (maxang > ovec0[2]) /* clamp near horizon */ |
337 |
|
maxang = ovec0[2]; |
338 |
|
r = maxang*(2.*GRIDRES/M_PI) + 1; |
343 |
|
for (jj = j-r; jj <= j+r; jj++) { |
344 |
|
if (jj < 0) continue; |
345 |
|
if (jj >= GRIDRES) break; |
346 |
< |
if (!bsdf_grid[ii][jj].nval) |
346 |
> |
if (!dsf_grid[ii][jj].nval) |
347 |
|
continue; |
348 |
|
if ((ii == i) & (jj == j)) |
349 |
|
continue; /* don't get self-absorbed */ |
351 |
|
if (2. - 2.*DOT(ovec0,ovec1) >= maxang2) |
352 |
|
continue; |
353 |
|
/* absorb sum */ |
354 |
< |
bsdf_grid[i][j].vsum += bsdf_grid[ii][jj].vsum; |
355 |
< |
bsdf_grid[i][j].nval += bsdf_grid[ii][jj].nval; |
354 |
> |
dsf_grid[i][j].vsum += dsf_grid[ii][jj].vsum; |
355 |
> |
dsf_grid[i][j].nval += dsf_grid[ii][jj].nval; |
356 |
|
/* keep value, though */ |
357 |
< |
bsdf_grid[ii][jj].vsum /= (double)bsdf_grid[ii][jj].nval; |
358 |
< |
bsdf_grid[ii][jj].nval = 0; |
357 |
> |
dsf_grid[ii][jj].vsum /= (double)dsf_grid[ii][jj].nval; |
358 |
> |
dsf_grid[ii][jj].nval = 0; |
359 |
|
} |
360 |
|
} |
361 |
|
} |
389 |
|
n = 0; |
390 |
|
for (i = 0; i < GRIDRES; i++) |
391 |
|
for (j = 0; j < GRIDRES; j++) |
392 |
< |
if (bsdf_grid[i][j].vsum > .0f) { |
388 |
< |
bsdf = bsdf_grid[i][j].vsum; |
392 |
> |
if (dsf_grid[i][j].vsum > .0f) { |
393 |
|
vec_from_pos(dir, i, j); |
394 |
< |
if (bsdf_grid[i][j].nval) { |
394 |
> |
bsdf = dsf_grid[i][j].vsum / dir[2]; |
395 |
> |
if (dsf_grid[i][j].nval) { |
396 |
|
printf("pink cone c%04d\n0\n0\n8\n", ++n); |
397 |
|
printf("\t%.6g %.6g %.6g\n", |
398 |
|
dir[0]*bsdf, dir[1]*bsdf, dir[2]*bsdf); |
410 |
|
/* output continuous surface */ |
411 |
|
puts("void trans tgreen\n0\n0\n7 .7 1 .7 .04 .04 .9 .9\n"); |
412 |
|
fflush(stdout); |
413 |
< |
sprintf(buf, "gensurf tgreen bsdf - - - %d %d", GRIDRES, GRIDRES); |
413 |
> |
sprintf(buf, "gensurf tgreen bsdf - - - %d %d", GRIDRES-1, GRIDRES-1); |
414 |
|
pfp = popen(buf, "w"); |
415 |
|
if (pfp == NULL) { |
416 |
|
fputs(buf, stderr); |
420 |
|
for (i = 0; i < GRIDRES; i++) |
421 |
|
for (j = 0; j < GRIDRES; j++) { |
422 |
|
vec_from_pos(dir, i, j); |
423 |
< |
bsdf = eval_rbfrep(bsdf_list, dir); |
423 |
> |
bsdf = eval_rbfrep(dsf_list, dir) / dir[2]; |
424 |
|
fprintf(pfp, "%.8e %.8e %.8e\n", |
425 |
|
dir[0]*bsdf, dir[1]*bsdf, dir[2]*bsdf); |
426 |
|
} |