| 7 |
|
* G. Ward |
| 8 |
|
*/ |
| 9 |
|
|
| 10 |
+ |
/**************************************************************** |
| 11 |
+ |
1) Collect samples into a grid using the Shirley-Chiu |
| 12 |
+ |
angular mapping from a hemisphere to a square. |
| 13 |
+ |
|
| 14 |
+ |
2) Compute an adaptive quadtree by subdividing the grid so that |
| 15 |
+ |
each leaf node has at least one sample up to as many |
| 16 |
+ |
samples as fit nicely on a plane to within a certain |
| 17 |
+ |
MSE tolerance. |
| 18 |
+ |
|
| 19 |
+ |
3) Place one Gaussian lobe at each leaf node in the quadtree, |
| 20 |
+ |
sizing it to have a radius equal to the leaf size and |
| 21 |
+ |
a volume equal to the energy in that node. |
| 22 |
+ |
*****************************************************************/ |
| 23 |
+ |
|
| 24 |
|
#define _USE_MATH_DEFINES |
| 25 |
|
#include <stdio.h> |
| 26 |
|
#include <stdlib.h> |
| 28 |
|
#include <math.h> |
| 29 |
|
#include "bsdfrep.h" |
| 30 |
|
|
| 31 |
< |
#ifndef MINRSCA |
| 32 |
< |
#define MINRSCA 0.5 /* minimum radius scaling factor */ |
| 31 |
> |
#ifndef RSCA |
| 32 |
> |
#define RSCA 2.0 /* radius scaling factor (empirical) */ |
| 33 |
|
#endif |
| 34 |
< |
#ifndef MAXRSCA |
| 35 |
< |
#define MAXRSCA 2.7 /* maximum radius scaling factor */ |
| 34 |
> |
#ifndef SMOOTH_MSE |
| 35 |
> |
#define SMOOTH_MSE 5e-5 /* acceptable mean squared error */ |
| 36 |
|
#endif |
| 37 |
< |
#ifndef DIFFTHRESH |
| 38 |
< |
#define DIFFTHRESH 0.2 /* culling difference threshold */ |
| 37 |
> |
#ifndef SMOOTH_MSER |
| 38 |
> |
#define SMOOTH_MSER 0.03 /* acceptable relative MSE */ |
| 39 |
|
#endif |
| 40 |
< |
#ifndef MAXFRAC |
| 41 |
< |
#define MAXFRAC 0.5 /* maximum contribution to neighbor */ |
| 42 |
< |
#endif |
| 43 |
< |
#ifndef NNEIGH |
| 44 |
< |
#define NNEIGH 10 /* number of neighbors to consider */ |
| 31 |
< |
#endif |
| 32 |
< |
/* our loaded grid for this incident angle */ |
| 40 |
> |
#define MAX_RAD (GRIDRES/8) /* maximum lobe radius */ |
| 41 |
> |
|
| 42 |
> |
#define RBFALLOCB 10 /* RBF allocation block size */ |
| 43 |
> |
|
| 44 |
> |
/* loaded grid or comparison DSFs */ |
| 45 |
|
GRIDVAL dsf_grid[GRIDRES][GRIDRES]; |
| 46 |
+ |
/* allocated chrominance sums if any */ |
| 47 |
+ |
float (*spec_grid)[GRIDRES][GRIDRES]; |
| 48 |
+ |
int nspec_grid = 0; |
| 49 |
|
|
| 50 |
+ |
/* Set up visible spectrum sampling */ |
| 51 |
+ |
void |
| 52 |
+ |
set_spectral_samples(int nspec) |
| 53 |
+ |
{ |
| 54 |
+ |
if (rbf_colorimetry == RBCunknown) { |
| 55 |
+ |
if (nspec_grid > 0) { |
| 56 |
+ |
free(spec_grid); |
| 57 |
+ |
spec_grid = NULL; |
| 58 |
+ |
nspec_grid = 0; |
| 59 |
+ |
} |
| 60 |
+ |
if (nspec == 1) { |
| 61 |
+ |
rbf_colorimetry = RBCphotopic; |
| 62 |
+ |
return; |
| 63 |
+ |
} |
| 64 |
+ |
if (nspec == 3) { |
| 65 |
+ |
rbf_colorimetry = RBCtristimulus; |
| 66 |
+ |
spec_grid = (float (*)[GRIDRES][GRIDRES])calloc( |
| 67 |
+ |
2*GRIDRES*GRIDRES, sizeof(float) ); |
| 68 |
+ |
if (spec_grid == NULL) |
| 69 |
+ |
goto mem_error; |
| 70 |
+ |
nspec_grid = 2; |
| 71 |
+ |
return; |
| 72 |
+ |
} |
| 73 |
+ |
fprintf(stderr, |
| 74 |
+ |
"%s: only 1 or 3 spectral samples currently supported\n", |
| 75 |
+ |
progname); |
| 76 |
+ |
exit(1); |
| 77 |
+ |
} |
| 78 |
+ |
if (nspec != nspec_grid+1) { |
| 79 |
+ |
fprintf(stderr, |
| 80 |
+ |
"%s: number of spectral samples cannot be changed\n", |
| 81 |
+ |
progname); |
| 82 |
+ |
exit(1); |
| 83 |
+ |
} |
| 84 |
+ |
return; |
| 85 |
+ |
mem_error: |
| 86 |
+ |
fprintf(stderr, "%s: out of memory in set_spectral_samples()\n", |
| 87 |
+ |
progname); |
| 88 |
+ |
exit(1); |
| 89 |
+ |
} |
| 90 |
+ |
|
| 91 |
|
/* Start new DSF input grid */ |
| 92 |
|
void |
| 93 |
|
new_bsdf_data(double new_theta, double new_phi) |
| 95 |
|
if (!new_input_direction(new_theta, new_phi)) |
| 96 |
|
exit(1); |
| 97 |
|
memset(dsf_grid, 0, sizeof(dsf_grid)); |
| 98 |
+ |
if (nspec_grid > 0) |
| 99 |
+ |
memset(spec_grid, 0, sizeof(float)*GRIDRES*GRIDRES*nspec_grid); |
| 100 |
|
} |
| 101 |
|
|
| 102 |
|
/* Add BSDF data point */ |
| 103 |
|
void |
| 104 |
< |
add_bsdf_data(double theta_out, double phi_out, double val, int isDSF) |
| 104 |
> |
add_bsdf_data(double theta_out, double phi_out, const double val[], int isDSF) |
| 105 |
|
{ |
| 106 |
|
FVECT ovec; |
| 107 |
+ |
double cfact, Yval; |
| 108 |
|
int pos[2]; |
| 109 |
|
|
| 110 |
+ |
if (nspec_grid > 2) { |
| 111 |
+ |
fprintf(stderr, "%s: unsupported color space\n", progname); |
| 112 |
+ |
exit(1); |
| 113 |
+ |
} |
| 114 |
|
if (!output_orient) /* check output orientation */ |
| 115 |
|
output_orient = 1 - 2*(theta_out > 90.); |
| 116 |
|
else if (output_orient > 0 ^ theta_out < 90.) { |
| 117 |
< |
fputs("Cannot handle output angles on both sides of surface\n", |
| 118 |
< |
stderr); |
| 117 |
> |
fprintf(stderr, |
| 118 |
> |
"%s: cannot handle output angles on both sides of surface\n", |
| 119 |
> |
progname); |
| 120 |
|
exit(1); |
| 121 |
|
} |
| 122 |
|
ovec[2] = sin((M_PI/180.)*theta_out); |
| 123 |
|
ovec[0] = cos((M_PI/180.)*phi_out) * ovec[2]; |
| 124 |
|
ovec[1] = sin((M_PI/180.)*phi_out) * ovec[2]; |
| 125 |
|
ovec[2] = sqrt(1. - ovec[2]*ovec[2]); |
| 126 |
+ |
/* BSDF to DSF correction */ |
| 127 |
+ |
cfact = isDSF ? 1. : ovec[2]; |
| 128 |
|
|
| 129 |
< |
if (val <= 0) /* truncate to zero */ |
| 64 |
< |
val = 0; |
| 65 |
< |
else if (!isDSF) |
| 66 |
< |
val *= ovec[2]; /* convert from BSDF to DSF */ |
| 67 |
< |
|
| 129 |
> |
Yval = cfact * val[rbf_colorimetry==RBCtristimulus]; |
| 130 |
|
/* update BSDF histogram */ |
| 131 |
< |
if (val < BSDF2BIG*ovec[2] && val > BSDF2SML*ovec[2]) |
| 132 |
< |
++bsdf_hist[histndx(val/ovec[2])]; |
| 131 |
> |
if (BSDF2SML*ovec[2] < Yval && Yval < BSDF2BIG*ovec[2]) |
| 132 |
> |
++bsdf_hist[histndx(Yval/ovec[2])]; |
| 133 |
|
|
| 134 |
|
pos_from_vec(pos, ovec); |
| 135 |
|
|
| 136 |
< |
dsf_grid[pos[0]][pos[1]].vsum += val; |
| 137 |
< |
dsf_grid[pos[0]][pos[1]].nval++; |
| 136 |
> |
dsf_grid[pos[0]][pos[1]].sum.v += Yval; |
| 137 |
> |
dsf_grid[pos[0]][pos[1]].sum.n++; |
| 138 |
> |
/* add in X and Z values */ |
| 139 |
> |
if (rbf_colorimetry == RBCtristimulus) { |
| 140 |
> |
spec_grid[0][pos[0]][pos[1]] += cfact * val[0]; |
| 141 |
> |
spec_grid[1][pos[0]][pos[1]] += cfact * val[2]; |
| 142 |
> |
} |
| 143 |
|
} |
| 144 |
|
|
| 145 |
< |
/* Check if the two DSF values are significantly different */ |
| 79 |
< |
static int |
| 80 |
< |
big_diff(double ref, double tst) |
| 81 |
< |
{ |
| 82 |
< |
if (ref > 0) { |
| 83 |
< |
tst = tst/ref - 1.; |
| 84 |
< |
if (tst < 0) tst = -tst; |
| 85 |
< |
} else |
| 86 |
< |
tst *= 50.; |
| 87 |
< |
return(tst > DIFFTHRESH); |
| 88 |
< |
} |
| 89 |
< |
|
| 90 |
< |
/* Compute radii for non-empty bins */ |
| 91 |
< |
/* (distance to furthest empty bin for which non-empty test bin is closest) */ |
| 145 |
> |
/* Compute minimum BSDF from histogram (does not clear) */ |
| 146 |
|
static void |
| 93 |
– |
compute_radii(void) |
| 94 |
– |
{ |
| 95 |
– |
const int cradmin = ANG2R(.5*M_PI/GRIDRES); |
| 96 |
– |
unsigned int fill_grid[GRIDRES][GRIDRES]; |
| 97 |
– |
unsigned short fill_cnt[GRIDRES][GRIDRES]; |
| 98 |
– |
FVECT ovec0, ovec1; |
| 99 |
– |
double ang2, lastang2; |
| 100 |
– |
int r, i, j, jn, ii, jj, inear, jnear; |
| 101 |
– |
|
| 102 |
– |
r = GRIDRES/2; /* proceed in zig-zag */ |
| 103 |
– |
for (i = 0; i < GRIDRES; i++) |
| 104 |
– |
for (jn = 0; jn < GRIDRES; jn++) { |
| 105 |
– |
j = (i&1) ? jn : GRIDRES-1-jn; |
| 106 |
– |
if (dsf_grid[i][j].nval) /* find empty grid pos. */ |
| 107 |
– |
continue; |
| 108 |
– |
ovec_from_pos(ovec0, i, j); |
| 109 |
– |
inear = jnear = -1; /* find nearest non-empty */ |
| 110 |
– |
lastang2 = M_PI*M_PI; |
| 111 |
– |
for (ii = i-r; ii <= i+r; ii++) { |
| 112 |
– |
if (ii < 0) continue; |
| 113 |
– |
if (ii >= GRIDRES) break; |
| 114 |
– |
for (jj = j-r; jj <= j+r; jj++) { |
| 115 |
– |
if (jj < 0) continue; |
| 116 |
– |
if (jj >= GRIDRES) break; |
| 117 |
– |
if (!dsf_grid[ii][jj].nval) |
| 118 |
– |
continue; |
| 119 |
– |
ovec_from_pos(ovec1, ii, jj); |
| 120 |
– |
ang2 = 2. - 2.*DOT(ovec0,ovec1); |
| 121 |
– |
if (ang2 >= lastang2) |
| 122 |
– |
continue; |
| 123 |
– |
lastang2 = ang2; |
| 124 |
– |
inear = ii; jnear = jj; |
| 125 |
– |
} |
| 126 |
– |
} |
| 127 |
– |
if (inear < 0) { |
| 128 |
– |
fprintf(stderr, |
| 129 |
– |
"%s: Could not find non-empty neighbor!\n", |
| 130 |
– |
progname); |
| 131 |
– |
exit(1); |
| 132 |
– |
} |
| 133 |
– |
ang2 = sqrt(lastang2); |
| 134 |
– |
r = ANG2R(ang2); /* record if > previous */ |
| 135 |
– |
if (r > dsf_grid[inear][jnear].crad) |
| 136 |
– |
dsf_grid[inear][jnear].crad = r; |
| 137 |
– |
/* next search radius */ |
| 138 |
– |
r = ang2*(2.*GRIDRES/M_PI) + 3; |
| 139 |
– |
} |
| 140 |
– |
for (i = 0; i < GRIDRES; i++) /* grow radii where uniform */ |
| 141 |
– |
for (j = 0; j < GRIDRES; j++) { |
| 142 |
– |
double midmean; |
| 143 |
– |
if (!dsf_grid[i][j].nval) |
| 144 |
– |
continue; |
| 145 |
– |
midmean = dsf_grid[i][j].vsum / (double)dsf_grid[i][j].nval; |
| 146 |
– |
r = R2ANG(dsf_grid[i][j].crad)*(MAXRSCA*GRIDRES/M_PI); |
| 147 |
– |
while (++r < GRIDRES) { /* attempt to grow perimeter */ |
| 148 |
– |
for (ii = i-r; ii <= i+r; ii++) { |
| 149 |
– |
int jstep = 1; |
| 150 |
– |
if (ii < 0) continue; |
| 151 |
– |
if (ii >= GRIDRES) break; |
| 152 |
– |
if ((i-r < ii) & (ii < i+r)) |
| 153 |
– |
jstep = r<<1; |
| 154 |
– |
for (jj = j-r; jj <= j+r; jj += jstep) { |
| 155 |
– |
if (jj < 0) continue; |
| 156 |
– |
if (jj >= GRIDRES) break; |
| 157 |
– |
if (dsf_grid[ii][jj].nval && big_diff(midmean, |
| 158 |
– |
dsf_grid[ii][jj].vsum / |
| 159 |
– |
(double)dsf_grid[ii][jj].nval)) |
| 160 |
– |
goto hit_diff; |
| 161 |
– |
} |
| 162 |
– |
} |
| 163 |
– |
} |
| 164 |
– |
hit_diff: --r; |
| 165 |
– |
dsf_grid[i][j].crad = ANG2R(r*(M_PI/MAXRSCA/GRIDRES)); |
| 166 |
– |
if (dsf_grid[i][j].crad < cradmin) |
| 167 |
– |
dsf_grid[i][j].crad = cradmin; |
| 168 |
– |
} |
| 169 |
– |
/* blur radii over hemisphere */ |
| 170 |
– |
memset(fill_grid, 0, sizeof(fill_grid)); |
| 171 |
– |
memset(fill_cnt, 0, sizeof(fill_cnt)); |
| 172 |
– |
for (i = 0; i < GRIDRES; i++) |
| 173 |
– |
for (j = 0; j < GRIDRES; j++) { |
| 174 |
– |
if (!dsf_grid[i][j].nval) |
| 175 |
– |
continue; /* not part of this */ |
| 176 |
– |
r = R2ANG(dsf_grid[i][j].crad)*(2.*MAXRSCA*GRIDRES/M_PI); |
| 177 |
– |
for (ii = i-r; ii <= i+r; ii++) { |
| 178 |
– |
if (ii < 0) continue; |
| 179 |
– |
if (ii >= GRIDRES) break; |
| 180 |
– |
for (jj = j-r; jj <= j+r; jj++) { |
| 181 |
– |
if (jj < 0) continue; |
| 182 |
– |
if (jj >= GRIDRES) break; |
| 183 |
– |
if ((ii-i)*(ii-i) + (jj-j)*(jj-j) > r*r) |
| 184 |
– |
continue; |
| 185 |
– |
fill_grid[ii][jj] += dsf_grid[i][j].crad; |
| 186 |
– |
fill_cnt[ii][jj]++; |
| 187 |
– |
} |
| 188 |
– |
} |
| 189 |
– |
} |
| 190 |
– |
/* copy back blurred radii */ |
| 191 |
– |
for (i = 0; i < GRIDRES; i++) |
| 192 |
– |
for (j = 0; j < GRIDRES; j++) |
| 193 |
– |
if (fill_cnt[i][j]) |
| 194 |
– |
dsf_grid[i][j].crad = fill_grid[i][j]/fill_cnt[i][j]; |
| 195 |
– |
} |
| 196 |
– |
|
| 197 |
– |
/* Cull points for more uniform distribution, leave all nval 0 or 1 */ |
| 198 |
– |
static void |
| 199 |
– |
cull_values(void) |
| 200 |
– |
{ |
| 201 |
– |
FVECT ovec0, ovec1; |
| 202 |
– |
double maxang, maxang2; |
| 203 |
– |
int i, j, ii, jj, r; |
| 204 |
– |
/* simple greedy algorithm */ |
| 205 |
– |
for (i = 0; i < GRIDRES; i++) |
| 206 |
– |
for (j = 0; j < GRIDRES; j++) { |
| 207 |
– |
if (!dsf_grid[i][j].nval) |
| 208 |
– |
continue; |
| 209 |
– |
if (!dsf_grid[i][j].crad) |
| 210 |
– |
continue; /* shouldn't happen */ |
| 211 |
– |
ovec_from_pos(ovec0, i, j); |
| 212 |
– |
maxang = 2.*R2ANG(dsf_grid[i][j].crad); |
| 213 |
– |
/* clamp near horizon */ |
| 214 |
– |
if (maxang > output_orient*ovec0[2]) |
| 215 |
– |
maxang = output_orient*ovec0[2]; |
| 216 |
– |
r = maxang*(2.*GRIDRES/M_PI) + 1; |
| 217 |
– |
maxang2 = maxang*maxang; |
| 218 |
– |
for (ii = i-r; ii <= i+r; ii++) { |
| 219 |
– |
if (ii < 0) continue; |
| 220 |
– |
if (ii >= GRIDRES) break; |
| 221 |
– |
for (jj = j-r; jj <= j+r; jj++) { |
| 222 |
– |
if ((ii == i) & (jj == j)) |
| 223 |
– |
continue; /* don't get self-absorbed */ |
| 224 |
– |
if (jj < 0) continue; |
| 225 |
– |
if (jj >= GRIDRES) break; |
| 226 |
– |
if (!dsf_grid[ii][jj].nval) |
| 227 |
– |
continue; |
| 228 |
– |
ovec_from_pos(ovec1, ii, jj); |
| 229 |
– |
if (2. - 2.*DOT(ovec0,ovec1) >= maxang2) |
| 230 |
– |
continue; |
| 231 |
– |
/* absorb sum */ |
| 232 |
– |
dsf_grid[i][j].vsum += dsf_grid[ii][jj].vsum; |
| 233 |
– |
dsf_grid[i][j].nval += dsf_grid[ii][jj].nval; |
| 234 |
– |
/* keep value, though */ |
| 235 |
– |
dsf_grid[ii][jj].vsum /= (float)dsf_grid[ii][jj].nval; |
| 236 |
– |
dsf_grid[ii][jj].nval = 0; |
| 237 |
– |
} |
| 238 |
– |
} |
| 239 |
– |
} |
| 240 |
– |
/* final averaging pass */ |
| 241 |
– |
for (i = 0; i < GRIDRES; i++) |
| 242 |
– |
for (j = 0; j < GRIDRES; j++) |
| 243 |
– |
if (dsf_grid[i][j].nval > 1) { |
| 244 |
– |
dsf_grid[i][j].vsum /= (float)dsf_grid[i][j].nval; |
| 245 |
– |
dsf_grid[i][j].nval = 1; |
| 246 |
– |
} |
| 247 |
– |
} |
| 248 |
– |
|
| 249 |
– |
/* Compute minimum BSDF from histogram and clear it */ |
| 250 |
– |
static void |
| 147 |
|
comp_bsdf_min() |
| 148 |
|
{ |
| 149 |
< |
int cnt; |
| 150 |
< |
int i, target; |
| 149 |
> |
unsigned long cnt, target; |
| 150 |
> |
int i; |
| 151 |
|
|
| 152 |
|
cnt = 0; |
| 153 |
|
for (i = HISTLEN; i--; ) |
| 161 |
|
for (i = 0; cnt <= target; i++) |
| 162 |
|
cnt += bsdf_hist[i]; |
| 163 |
|
bsdf_min = histval(i-1); |
| 268 |
– |
memset(bsdf_hist, 0, sizeof(bsdf_hist)); |
| 164 |
|
} |
| 165 |
|
|
| 166 |
< |
/* Find n nearest sub-sampled neighbors to the given grid position */ |
| 166 |
> |
/* Determine if the given region is empty of grid samples */ |
| 167 |
|
static int |
| 168 |
< |
get_neighbors(int neigh[][2], int n, const int i, const int j) |
| 168 |
> |
empty_region(int x0, int x1, int y0, int y1) |
| 169 |
|
{ |
| 170 |
< |
int k = 0; |
| 171 |
< |
int r; |
| 172 |
< |
/* search concentric squares */ |
| 173 |
< |
for (r = 1; r < GRIDRES; r++) { |
| 174 |
< |
int ii, jj; |
| 175 |
< |
for (ii = i-r; ii <= i+r; ii++) { |
| 176 |
< |
int jstep = 1; |
| 177 |
< |
if (ii < 0) continue; |
| 178 |
< |
if (ii >= GRIDRES) break; |
| 179 |
< |
if ((i-r < ii) & (ii < i+r)) |
| 180 |
< |
jstep = r<<1; |
| 181 |
< |
for (jj = j-r; jj <= j+r; jj += jstep) { |
| 182 |
< |
if (jj < 0) continue; |
| 183 |
< |
if (jj >= GRIDRES) break; |
| 184 |
< |
if (dsf_grid[ii][jj].nval) { |
| 185 |
< |
neigh[k][0] = ii; |
| 186 |
< |
neigh[k][1] = jj; |
| 187 |
< |
if (++k >= n) |
| 188 |
< |
return(n); |
| 189 |
< |
} |
| 190 |
< |
} |
| 170 |
> |
int x, y; |
| 171 |
> |
|
| 172 |
> |
for (x = x0; x < x1; x++) |
| 173 |
> |
for (y = y0; y < y1; y++) |
| 174 |
> |
if (dsf_grid[x][y].sum.n) |
| 175 |
> |
return(0); |
| 176 |
> |
return(1); |
| 177 |
> |
} |
| 178 |
> |
|
| 179 |
> |
/* Determine if the given region is smooth enough to be a single lobe */ |
| 180 |
> |
static int |
| 181 |
> |
smooth_region(int x0, int x1, int y0, int y1) |
| 182 |
> |
{ |
| 183 |
> |
RREAL rMtx[3][3]; |
| 184 |
> |
FVECT xvec; |
| 185 |
> |
double A, B, C, nvs, sqerr; |
| 186 |
> |
int x, y, n; |
| 187 |
> |
/* compute planar regression */ |
| 188 |
> |
memset(rMtx, 0, sizeof(rMtx)); |
| 189 |
> |
memset(xvec, 0, sizeof(xvec)); |
| 190 |
> |
for (x = x0; x < x1; x++) |
| 191 |
> |
for (y = y0; y < y1; y++) |
| 192 |
> |
if ((n = dsf_grid[x][y].sum.n) > 0) { |
| 193 |
> |
double z = dsf_grid[x][y].sum.v; |
| 194 |
> |
rMtx[0][0] += x*x*(double)n; |
| 195 |
> |
rMtx[0][1] += x*y*(double)n; |
| 196 |
> |
rMtx[0][2] += x*(double)n; |
| 197 |
> |
rMtx[1][1] += y*y*(double)n; |
| 198 |
> |
rMtx[1][2] += y*(double)n; |
| 199 |
> |
rMtx[2][2] += (double)n; |
| 200 |
> |
xvec[0] += x*z; |
| 201 |
> |
xvec[1] += y*z; |
| 202 |
> |
xvec[2] += z; |
| 203 |
|
} |
| 204 |
< |
} |
| 205 |
< |
return(k); |
| 204 |
> |
rMtx[1][0] = rMtx[0][1]; |
| 205 |
> |
rMtx[2][0] = rMtx[0][2]; |
| 206 |
> |
rMtx[2][1] = rMtx[1][2]; |
| 207 |
> |
nvs = rMtx[2][2]; |
| 208 |
> |
if (SDinvXform(rMtx, rMtx) != SDEnone) |
| 209 |
> |
return(1); /* colinear values */ |
| 210 |
> |
A = DOT(rMtx[0], xvec); |
| 211 |
> |
B = DOT(rMtx[1], xvec); |
| 212 |
> |
C = DOT(rMtx[2], xvec); |
| 213 |
> |
sqerr = 0.0; /* compute mean squared error */ |
| 214 |
> |
for (x = x0; x < x1; x++) |
| 215 |
> |
for (y = y0; y < y1; y++) |
| 216 |
> |
if ((n = dsf_grid[x][y].sum.n) > 0) { |
| 217 |
> |
double d = A*x + B*y + C - dsf_grid[x][y].sum.v/n; |
| 218 |
> |
sqerr += n*d*d; |
| 219 |
> |
} |
| 220 |
> |
if (sqerr <= nvs*SMOOTH_MSE) /* below absolute MSE threshold? */ |
| 221 |
> |
return(1); |
| 222 |
> |
/* OR below relative MSE threshold? */ |
| 223 |
> |
return(sqerr*nvs <= xvec[2]*xvec[2]*SMOOTH_MSER); |
| 224 |
|
} |
| 225 |
|
|
| 226 |
< |
/* Adjust coded radius for the given grid position based on neighborhood */ |
| 226 |
> |
/* Create new lobe based on integrated samples in region */ |
| 227 |
|
static int |
| 228 |
< |
adj_coded_radius(const int i, const int j) |
| 228 |
> |
create_lobe(RBFVAL *rvp, int x0, int x1, int y0, int y1) |
| 229 |
|
{ |
| 230 |
< |
const double rad0 = R2ANG(dsf_grid[i][j].crad); |
| 231 |
< |
const double minrad = MINRSCA * rad0; |
| 232 |
< |
double currad = MAXRSCA * rad0; |
| 233 |
< |
int neigh[NNEIGH][2]; |
| 234 |
< |
int n; |
| 235 |
< |
FVECT our_dir; |
| 230 |
> |
double vtot = 0.0; |
| 231 |
> |
double CIEXtot = 0.0, CIEZtot = 0.0; |
| 232 |
> |
int nv = 0; |
| 233 |
> |
double wxsum = 0.0, wysum = 0.0, wtsum = 0.0; |
| 234 |
> |
double rad; |
| 235 |
> |
int x, y; |
| 236 |
> |
/* compute average for region */ |
| 237 |
> |
for (x = x0; x < x1; x++) |
| 238 |
> |
for (y = y0; y < y1; y++) |
| 239 |
> |
if (dsf_grid[x][y].sum.n) { |
| 240 |
> |
const double v = dsf_grid[x][y].sum.v; |
| 241 |
> |
const int n = dsf_grid[x][y].sum.n; |
| 242 |
|
|
| 243 |
< |
ovec_from_pos(our_dir, i, j); |
| 244 |
< |
n = get_neighbors(neigh, NNEIGH, i, j); |
| 245 |
< |
while (n--) { |
| 246 |
< |
FVECT their_dir; |
| 247 |
< |
double max_ratio, rad_ok2; |
| 248 |
< |
/* check our value at neighbor */ |
| 249 |
< |
ovec_from_pos(their_dir, neigh[n][0], neigh[n][1]); |
| 250 |
< |
max_ratio = MAXFRAC * dsf_grid[neigh[n][0]][neigh[n][1]].vsum |
| 251 |
< |
/ dsf_grid[i][j].vsum; |
| 252 |
< |
if (max_ratio >= 1) |
| 253 |
< |
continue; |
| 254 |
< |
rad_ok2 = (DOT(their_dir,our_dir) - 1.)/log(max_ratio); |
| 255 |
< |
if (rad_ok2 >= currad*currad) |
| 256 |
< |
continue; /* value fraction OK */ |
| 257 |
< |
currad = sqrt(rad_ok2); /* else reduce lobe radius */ |
| 258 |
< |
if (currad <= minrad) /* limit how small we'll go */ |
| 259 |
< |
return(ANG2R(minrad)); |
| 243 |
> |
if (v > 0) { |
| 244 |
> |
const double wt = v / (double)n; |
| 245 |
> |
wxsum += wt * x; |
| 246 |
> |
wysum += wt * y; |
| 247 |
> |
wtsum += wt; |
| 248 |
> |
} |
| 249 |
> |
vtot += v; |
| 250 |
> |
nv += n; |
| 251 |
> |
if (rbf_colorimetry == RBCtristimulus) { |
| 252 |
> |
CIEXtot += spec_grid[0][x][y]; |
| 253 |
> |
CIEZtot += spec_grid[1][x][y]; |
| 254 |
> |
} |
| 255 |
> |
} |
| 256 |
> |
if (!nv) { |
| 257 |
> |
fprintf(stderr, "%s: internal - missing samples in create_lobe\n", |
| 258 |
> |
progname); |
| 259 |
> |
exit(1); |
| 260 |
|
} |
| 261 |
< |
return(ANG2R(currad)); /* encode selected radius */ |
| 261 |
> |
if (vtot <= 0) /* only create positive lobes */ |
| 262 |
> |
return(0); |
| 263 |
> |
/* assign color */ |
| 264 |
> |
if (rbf_colorimetry == RBCtristimulus) { |
| 265 |
> |
const double df = 1.0 / (CIEXtot + vtot + CIEZtot); |
| 266 |
> |
C_COLOR cclr; |
| 267 |
> |
c_cset(&cclr, CIEXtot*df, vtot*df); |
| 268 |
> |
rvp->chroma = c_encodeChroma(&cclr); |
| 269 |
> |
} else |
| 270 |
> |
rvp->chroma = c_dfchroma; |
| 271 |
> |
/* peak value based on integral */ |
| 272 |
> |
vtot *= (x1-x0)*(y1-y0)*(2.*M_PI/GRIDRES/GRIDRES)/(double)nv; |
| 273 |
> |
rad = (RSCA/(double)GRIDRES)*(x1-x0); |
| 274 |
> |
rvp->peak = vtot / ((2.*M_PI) * rad*rad); |
| 275 |
> |
rvp->crad = ANG2R(rad); /* put peak at centroid */ |
| 276 |
> |
rvp->gx = (int)(wxsum/wtsum + .5); |
| 277 |
> |
rvp->gy = (int)(wysum/wtsum + .5); |
| 278 |
> |
return(1); |
| 279 |
|
} |
| 280 |
|
|
| 281 |
+ |
/* Recursive function to build radial basis function representation */ |
| 282 |
+ |
static int |
| 283 |
+ |
build_rbfrep(RBFVAL **arp, int *np, int x0, int x1, int y0, int y1) |
| 284 |
+ |
{ |
| 285 |
+ |
int xmid = (x0+x1)>>1; |
| 286 |
+ |
int ymid = (y0+y1)>>1; |
| 287 |
+ |
int branched[4]; |
| 288 |
+ |
int nadded, nleaves; |
| 289 |
+ |
/* need to make this a leaf? */ |
| 290 |
+ |
if (empty_region(x0, xmid, y0, ymid) || |
| 291 |
+ |
empty_region(xmid, x1, y0, ymid) || |
| 292 |
+ |
empty_region(x0, xmid, ymid, y1) || |
| 293 |
+ |
empty_region(xmid, x1, ymid, y1)) |
| 294 |
+ |
return(0); |
| 295 |
+ |
/* add children (branches+leaves) */ |
| 296 |
+ |
if ((branched[0] = build_rbfrep(arp, np, x0, xmid, y0, ymid)) < 0) |
| 297 |
+ |
return(-1); |
| 298 |
+ |
if ((branched[1] = build_rbfrep(arp, np, xmid, x1, y0, ymid)) < 0) |
| 299 |
+ |
return(-1); |
| 300 |
+ |
if ((branched[2] = build_rbfrep(arp, np, x0, xmid, ymid, y1)) < 0) |
| 301 |
+ |
return(-1); |
| 302 |
+ |
if ((branched[3] = build_rbfrep(arp, np, xmid, x1, ymid, y1)) < 0) |
| 303 |
+ |
return(-1); |
| 304 |
+ |
nadded = branched[0] + branched[1] + branched[2] + branched[3]; |
| 305 |
+ |
nleaves = !branched[0] + !branched[1] + !branched[2] + !branched[3]; |
| 306 |
+ |
if (!nleaves) /* nothing but branches? */ |
| 307 |
+ |
return(nadded); |
| 308 |
+ |
/* combine 4 leaves into 1? */ |
| 309 |
+ |
if ((nleaves == 4) & (x1-x0 <= MAX_RAD) && |
| 310 |
+ |
smooth_region(x0, x1, y0, y1)) |
| 311 |
+ |
return(0); |
| 312 |
+ |
/* need more array space? */ |
| 313 |
+ |
if ((*np+nleaves-1)>>RBFALLOCB != (*np-1)>>RBFALLOCB) { |
| 314 |
+ |
*arp = (RBFVAL *)realloc(*arp, |
| 315 |
+ |
sizeof(RBFVAL)*(*np+nleaves-1+(1<<RBFALLOCB))); |
| 316 |
+ |
if (*arp == NULL) |
| 317 |
+ |
return(-1); |
| 318 |
+ |
} |
| 319 |
+ |
/* create lobes for leaves */ |
| 320 |
+ |
if (!branched[0] && create_lobe(*arp+*np, x0, xmid, y0, ymid)) { |
| 321 |
+ |
++(*np); ++nadded; |
| 322 |
+ |
} |
| 323 |
+ |
if (!branched[1] && create_lobe(*arp+*np, xmid, x1, y0, ymid)) { |
| 324 |
+ |
++(*np); ++nadded; |
| 325 |
+ |
} |
| 326 |
+ |
if (!branched[2] && create_lobe(*arp+*np, x0, xmid, ymid, y1)) { |
| 327 |
+ |
++(*np); ++nadded; |
| 328 |
+ |
} |
| 329 |
+ |
if (!branched[3] && create_lobe(*arp+*np, xmid, x1, ymid, y1)) { |
| 330 |
+ |
++(*np); ++nadded; |
| 331 |
+ |
} |
| 332 |
+ |
return(nadded); |
| 333 |
+ |
} |
| 334 |
+ |
|
| 335 |
|
/* Count up filled nodes and build RBF representation from current grid */ |
| 336 |
|
RBFNODE * |
| 337 |
< |
make_rbfrep(void) |
| 337 |
> |
make_rbfrep() |
| 338 |
|
{ |
| 337 |
– |
long cradsum = 0, ocradsum = 0; |
| 338 |
– |
int niter = 16; |
| 339 |
– |
double lastVar, thisVar = 100.; |
| 340 |
– |
int nn; |
| 339 |
|
RBFNODE *newnode; |
| 340 |
< |
RBFVAL *itera; |
| 341 |
< |
int i, j; |
| 344 |
< |
|
| 345 |
< |
#ifdef DEBUG |
| 346 |
< |
{ |
| 347 |
< |
int maxcnt = 0, nempty = 0; |
| 348 |
< |
long cntsum = 0; |
| 349 |
< |
for (i = 0; i < GRIDRES; i++) |
| 350 |
< |
for (j = 0; j < GRIDRES; j++) |
| 351 |
< |
if (!dsf_grid[i][j].nval) { |
| 352 |
< |
++nempty; |
| 353 |
< |
} else { |
| 354 |
< |
if (dsf_grid[i][j].nval > maxcnt) |
| 355 |
< |
maxcnt = dsf_grid[i][j].nval; |
| 356 |
< |
cntsum += dsf_grid[i][j].nval; |
| 357 |
< |
} |
| 358 |
< |
fprintf(stderr, "Average, maximum bin count: %d, %d (%.1f%% empty)\n", |
| 359 |
< |
(int)(cntsum/((GRIDRES*GRIDRES)-nempty)), maxcnt, |
| 360 |
< |
100./(GRIDRES*GRIDRES)*nempty); |
| 361 |
< |
} |
| 362 |
< |
#endif |
| 363 |
< |
/* compute RBF radii */ |
| 364 |
< |
compute_radii(); |
| 365 |
< |
/* coagulate lobes */ |
| 366 |
< |
cull_values(); |
| 367 |
< |
nn = 0; /* count selected bins */ |
| 368 |
< |
for (i = 0; i < GRIDRES; i++) |
| 369 |
< |
for (j = 0; j < GRIDRES; j++) |
| 370 |
< |
nn += dsf_grid[i][j].nval; |
| 340 |
> |
RBFVAL *rbfarr; |
| 341 |
> |
int nn; |
| 342 |
|
/* compute minimum BSDF */ |
| 343 |
|
comp_bsdf_min(); |
| 344 |
< |
/* allocate RBF array */ |
| 345 |
< |
newnode = (RBFNODE *)malloc(sizeof(RBFNODE) + sizeof(RBFVAL)*(nn-1)); |
| 344 |
> |
/* create RBF node list */ |
| 345 |
> |
rbfarr = NULL; nn = 0; |
| 346 |
> |
if (build_rbfrep(&rbfarr, &nn, 0, GRIDRES, 0, GRIDRES) <= 0) { |
| 347 |
> |
if (nn) |
| 348 |
> |
goto memerr; |
| 349 |
> |
fprintf(stderr, |
| 350 |
> |
"%s: warning - skipping bad incidence (%.1f,%.1f)\n", |
| 351 |
> |
progname, theta_in_deg, phi_in_deg); |
| 352 |
> |
return(NULL); |
| 353 |
> |
} |
| 354 |
> |
/* (re)allocate RBF array */ |
| 355 |
> |
newnode = (RBFNODE *)realloc(rbfarr, |
| 356 |
> |
sizeof(RBFNODE) + sizeof(RBFVAL)*(nn-1)); |
| 357 |
|
if (newnode == NULL) |
| 358 |
|
goto memerr; |
| 359 |
+ |
/* copy computed lobes into RBF node */ |
| 360 |
+ |
memmove(newnode->rbfa, newnode, sizeof(RBFVAL)*nn); |
| 361 |
|
newnode->ord = -1; |
| 362 |
|
newnode->next = NULL; |
| 363 |
|
newnode->ejl = NULL; |
| 365 |
|
newnode->invec[0] = cos((M_PI/180.)*phi_in_deg)*newnode->invec[2]; |
| 366 |
|
newnode->invec[1] = sin((M_PI/180.)*phi_in_deg)*newnode->invec[2]; |
| 367 |
|
newnode->invec[2] = input_orient*sqrt(1. - newnode->invec[2]*newnode->invec[2]); |
| 368 |
< |
newnode->vtotal = 0; |
| 368 |
> |
newnode->vtotal = .0; |
| 369 |
|
newnode->nrbf = nn; |
| 370 |
< |
nn = 0; /* fill RBF array */ |
| 371 |
< |
for (i = 0; i < GRIDRES; i++) |
| 372 |
< |
for (j = 0; j < GRIDRES; j++) |
| 389 |
< |
if (dsf_grid[i][j].nval) { |
| 390 |
< |
newnode->rbfa[nn].peak = dsf_grid[i][j].vsum; |
| 391 |
< |
ocradsum += dsf_grid[i][j].crad; |
| 392 |
< |
cradsum += |
| 393 |
< |
newnode->rbfa[nn].crad = adj_coded_radius(i, j); |
| 394 |
< |
newnode->rbfa[nn].gx = i; |
| 395 |
< |
newnode->rbfa[nn].gy = j; |
| 396 |
< |
++nn; |
| 397 |
< |
} |
| 370 |
> |
/* compute sum for normalization */ |
| 371 |
> |
while (nn-- > 0) |
| 372 |
> |
newnode->vtotal += rbf_volume(&newnode->rbfa[nn]); |
| 373 |
|
#ifdef DEBUG |
| 374 |
< |
fprintf(stderr, |
| 400 |
< |
"Average radius reduced from %.2f to %.2f degrees for %d lobes\n", |
| 401 |
< |
180./M_PI*MAXRSCA*R2ANG(ocradsum/newnode->nrbf), |
| 402 |
< |
180./M_PI*R2ANG(cradsum/newnode->nrbf), newnode->nrbf); |
| 403 |
< |
#endif |
| 404 |
< |
/* iterate to improve interpolation accuracy */ |
| 405 |
< |
itera = (RBFVAL *)malloc(sizeof(RBFVAL)*newnode->nrbf); |
| 406 |
< |
if (itera == NULL) |
| 407 |
< |
goto memerr; |
| 408 |
< |
memcpy(itera, newnode->rbfa, sizeof(RBFVAL)*newnode->nrbf); |
| 409 |
< |
do { |
| 410 |
< |
double dsum = 0, dsum2 = 0; |
| 411 |
< |
nn = 0; |
| 412 |
< |
for (i = 0; i < GRIDRES; i++) |
| 413 |
< |
for (j = 0; j < GRIDRES; j++) |
| 414 |
< |
if (dsf_grid[i][j].nval) { |
| 415 |
< |
FVECT odir; |
| 416 |
< |
double corr; |
| 417 |
< |
ovec_from_pos(odir, i, j); |
| 418 |
< |
itera[nn++].peak *= corr = |
| 419 |
< |
dsf_grid[i][j].vsum / |
| 420 |
< |
eval_rbfrep(newnode, odir); |
| 421 |
< |
dsum += 1. - corr; |
| 422 |
< |
dsum2 += (1.-corr)*(1.-corr); |
| 423 |
< |
} |
| 424 |
< |
memcpy(newnode->rbfa, itera, sizeof(RBFVAL)*newnode->nrbf); |
| 425 |
< |
lastVar = thisVar; |
| 426 |
< |
thisVar = dsum2/(double)nn; |
| 427 |
< |
#ifdef DEBUG |
| 428 |
< |
fprintf(stderr, "Avg., RMS error: %.1f%% %.1f%%\n", |
| 429 |
< |
100.*dsum/(double)nn, |
| 430 |
< |
100.*sqrt(thisVar)); |
| 431 |
< |
#endif |
| 432 |
< |
} while (--niter > 0 && lastVar-thisVar > 0.02*lastVar); |
| 433 |
< |
|
| 434 |
< |
free(itera); |
| 435 |
< |
nn = 0; /* compute sum for normalization */ |
| 436 |
< |
while (nn < newnode->nrbf) |
| 437 |
< |
newnode->vtotal += rbf_volume(&newnode->rbfa[nn++]); |
| 438 |
< |
#ifdef DEBUG |
| 374 |
> |
fprintf(stderr, "Built RBF with %d lobes\n", newnode->nrbf); |
| 375 |
|
fprintf(stderr, "Integrated DSF at (%.1f,%.1f) deg. is %.2f\n", |
| 376 |
|
get_theta180(newnode->invec), get_phi360(newnode->invec), |
| 377 |
|
newnode->vtotal); |
| 378 |
|
#endif |
| 379 |
|
insert_dsf(newnode); |
| 444 |
– |
|
| 380 |
|
return(newnode); |
| 381 |
|
memerr: |
| 382 |
|
fprintf(stderr, "%s: Out of memory in make_rbfrep()\n", progname); |
