1 |
greg |
1.1 |
#ifndef lint |
2 |
greg |
2.46 |
static const char RCSid[] = "$Id: ambcomp.c,v 2.45 2014/05/01 22:34:25 greg Exp $"; |
3 |
greg |
1.1 |
#endif |
4 |
|
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/* |
5 |
|
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* Routines to compute "ambient" values using Monte Carlo |
6 |
greg |
2.9 |
* |
7 |
greg |
2.27 |
* Hessian calculations based on "Practical Hessian-Based Error Control |
8 |
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* for Irradiance Caching" by Schwarzhaupt, Wann Jensen, & Jarosz |
9 |
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* from ACM SIGGRAPH Asia 2012 conference proceedings. |
10 |
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* |
11 |
greg |
2.46 |
* Added book-keeping optimization to avoid calculations that would |
12 |
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* cancel due to traversal both directions on edges that are adjacent |
13 |
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* to same-valued triangles. This cuts about half of Hessian math. |
14 |
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* |
15 |
greg |
2.9 |
* Declarations of external symbols in ambient.h |
16 |
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*/ |
17 |
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18 |
greg |
2.10 |
#include "copyright.h" |
19 |
greg |
1.1 |
|
20 |
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#include "ray.h" |
21 |
greg |
2.25 |
#include "ambient.h" |
22 |
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#include "random.h" |
23 |
greg |
1.1 |
|
24 |
greg |
2.25 |
#ifdef NEWAMB |
25 |
greg |
1.1 |
|
26 |
greg |
2.26 |
extern void SDsquare2disk(double ds[2], double seedx, double seedy); |
27 |
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|
28 |
greg |
2.46 |
/* vertex direction bit positions */ |
29 |
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#define VDB_xy 0 |
30 |
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#define VDB_y 01 |
31 |
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#define VDB_x 02 |
32 |
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#define VDB_Xy 03 |
33 |
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#define VDB_xY 04 |
34 |
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#define VDB_X 05 |
35 |
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#define VDB_Y 06 |
36 |
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#define VDB_XY 07 |
37 |
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/* get opposite vertex direction bit */ |
38 |
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#define VDB_OPP(f) (~(f) & 07) |
39 |
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/* adjacent triangle vertex flags */ |
40 |
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static const int adjacent_trifl[8] = { |
41 |
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0, /* forbidden diagonal */ |
42 |
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1<<VDB_x|1<<VDB_y|1<<VDB_Xy, |
43 |
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1<<VDB_y|1<<VDB_x|1<<VDB_xY, |
44 |
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1<<VDB_y|1<<VDB_Xy|1<<VDB_X, |
45 |
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1<<VDB_x|1<<VDB_xY|1<<VDB_Y, |
46 |
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1<<VDB_Xy|1<<VDB_X|1<<VDB_Y, |
47 |
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1<<VDB_xY|1<<VDB_Y|1<<VDB_X, |
48 |
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0, /* forbidden diagonal */ |
49 |
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}; |
50 |
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51 |
greg |
2.26 |
typedef struct { |
52 |
greg |
2.44 |
COLOR v; /* hemisphere sample value */ |
53 |
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FVECT p; /* intersection point */ |
54 |
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} AMBSAMP; /* sample value */ |
55 |
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56 |
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typedef struct { |
57 |
greg |
2.26 |
RAY *rp; /* originating ray sample */ |
58 |
greg |
2.27 |
FVECT ux, uy; /* tangent axis unit vectors */ |
59 |
greg |
2.26 |
int ns; /* number of samples per axis */ |
60 |
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COLOR acoef; /* division contribution coefficient */ |
61 |
greg |
2.44 |
AMBSAMP sa[1]; /* sample array (extends struct) */ |
62 |
greg |
2.26 |
} AMBHEMI; /* ambient sample hemisphere */ |
63 |
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|
64 |
greg |
2.46 |
#define ambndx(h,i,j) ((i)*(h)->ns + (j)) |
65 |
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#define ambsam(h,i,j) (h)->sa[ambndx(h,i,j)] |
66 |
greg |
2.26 |
|
67 |
greg |
2.27 |
typedef struct { |
68 |
greg |
2.35 |
FVECT r_i, r_i1, e_i, rcp, rI2_eJ2; |
69 |
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double I1, I2; |
70 |
greg |
2.46 |
int valid; |
71 |
greg |
2.27 |
} FFTRI; /* vectors and coefficients for Hessian calculation */ |
72 |
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73 |
greg |
2.26 |
|
74 |
greg |
2.46 |
/* Get index for adjacent vertex */ |
75 |
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static int |
76 |
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adjacent_verti(AMBHEMI *hp, int i, int j, int dbit) |
77 |
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{ |
78 |
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int i0 = i*hp->ns + j; |
79 |
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80 |
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switch (dbit) { |
81 |
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case VDB_y: return(i0 - hp->ns); |
82 |
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case VDB_x: return(i0 - 1); |
83 |
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case VDB_Xy: return(i0 - hp->ns + 1); |
84 |
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case VDB_xY: return(i0 + hp->ns - 1); |
85 |
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case VDB_X: return(i0 + 1); |
86 |
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case VDB_Y: return(i0 + hp->ns); |
87 |
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/* the following should never occur */ |
88 |
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case VDB_xy: return(i0 - hp->ns - 1); |
89 |
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case VDB_XY: return(i0 + hp->ns + 1); |
90 |
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} |
91 |
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return(-1); |
92 |
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} |
93 |
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94 |
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95 |
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/* Get vertex direction bit for the opposite edge to complete triangle */ |
96 |
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static int |
97 |
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vdb_edge(int db1, int db2) |
98 |
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{ |
99 |
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switch (db1) { |
100 |
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case VDB_x: return(db2==VDB_y ? VDB_Xy : VDB_Y); |
101 |
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case VDB_y: return(db2==VDB_x ? VDB_xY : VDB_X); |
102 |
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case VDB_X: return(db2==VDB_Xy ? VDB_y : VDB_xY); |
103 |
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case VDB_Y: return(db2==VDB_xY ? VDB_x : VDB_Xy); |
104 |
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case VDB_xY: return(db2==VDB_x ? VDB_y : VDB_X); |
105 |
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case VDB_Xy: return(db2==VDB_y ? VDB_x : VDB_Y); |
106 |
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} |
107 |
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error(INTERNAL, "forbidden diagonal in vdb_edge()"); |
108 |
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return(-1); |
109 |
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} |
110 |
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111 |
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112 |
greg |
2.26 |
static AMBHEMI * |
113 |
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inithemi( /* initialize sampling hemisphere */ |
114 |
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COLOR ac, |
115 |
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RAY *r, |
116 |
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double wt |
117 |
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) |
118 |
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{ |
119 |
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AMBHEMI *hp; |
120 |
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double d; |
121 |
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int n, i; |
122 |
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/* set number of divisions */ |
123 |
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if (ambacc <= FTINY && |
124 |
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wt > (d = 0.8*intens(ac)*r->rweight/(ambdiv*minweight))) |
125 |
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wt = d; /* avoid ray termination */ |
126 |
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n = sqrt(ambdiv * wt) + 0.5; |
127 |
greg |
2.27 |
i = 1 + 5*(ambacc > FTINY); /* minimum number of samples */ |
128 |
greg |
2.26 |
if (n < i) |
129 |
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n = i; |
130 |
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/* allocate sampling array */ |
131 |
greg |
2.41 |
hp = (AMBHEMI *)malloc(sizeof(AMBHEMI) + sizeof(AMBSAMP)*(n*n - 1)); |
132 |
greg |
2.26 |
if (hp == NULL) |
133 |
|
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return(NULL); |
134 |
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hp->rp = r; |
135 |
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hp->ns = n; |
136 |
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/* assign coefficient */ |
137 |
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copycolor(hp->acoef, ac); |
138 |
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d = 1.0/(n*n); |
139 |
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scalecolor(hp->acoef, d); |
140 |
greg |
2.28 |
/* make tangent plane axes */ |
141 |
greg |
2.38 |
hp->uy[0] = 0.5 - frandom(); |
142 |
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hp->uy[1] = 0.5 - frandom(); |
143 |
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hp->uy[2] = 0.5 - frandom(); |
144 |
greg |
2.36 |
for (i = 3; i--; ) |
145 |
greg |
2.37 |
if ((-0.6 < r->ron[i]) & (r->ron[i] < 0.6)) |
146 |
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break; |
147 |
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if (i < 0) |
148 |
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error(CONSISTENCY, "bad ray direction in inithemi"); |
149 |
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hp->uy[i] = 1.0; |
150 |
greg |
2.27 |
VCROSS(hp->ux, hp->uy, r->ron); |
151 |
greg |
2.26 |
normalize(hp->ux); |
152 |
greg |
2.27 |
VCROSS(hp->uy, r->ron, hp->ux); |
153 |
greg |
2.26 |
/* we're ready to sample */ |
154 |
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return(hp); |
155 |
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} |
156 |
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157 |
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|
158 |
greg |
2.43 |
/* Sample ambient division and apply weighting coefficient */ |
159 |
greg |
2.41 |
static int |
160 |
greg |
2.43 |
getambsamp(RAY *arp, AMBHEMI *hp, int i, int j, int n) |
161 |
greg |
2.26 |
{ |
162 |
greg |
2.41 |
int hlist[3], ii; |
163 |
|
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double spt[2], zd; |
164 |
greg |
2.26 |
/* ambient coefficient for weight */ |
165 |
|
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if (ambacc > FTINY) |
166 |
greg |
2.41 |
setcolor(arp->rcoef, AVGREFL, AVGREFL, AVGREFL); |
167 |
greg |
2.26 |
else |
168 |
greg |
2.41 |
copycolor(arp->rcoef, hp->acoef); |
169 |
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if (rayorigin(arp, AMBIENT, hp->rp, arp->rcoef) < 0) |
170 |
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return(0); |
171 |
greg |
2.26 |
if (ambacc > FTINY) { |
172 |
greg |
2.41 |
multcolor(arp->rcoef, hp->acoef); |
173 |
|
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scalecolor(arp->rcoef, 1./AVGREFL); |
174 |
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} |
175 |
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hlist[0] = hp->rp->rno; |
176 |
greg |
2.46 |
hlist[1] = j; |
177 |
|
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hlist[2] = i; |
178 |
greg |
2.41 |
multisamp(spt, 2, urand(ilhash(hlist,3)+n)); |
179 |
|
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if (!n) { /* avoid border samples for n==0 */ |
180 |
greg |
2.46 |
if ((spt[0] < 0.1) | (spt[0] >= 0.9)) |
181 |
greg |
2.41 |
spt[0] = 0.1 + 0.8*frandom(); |
182 |
greg |
2.46 |
if ((spt[1] < 0.1) | (spt[1] >= 0.9)) |
183 |
greg |
2.41 |
spt[1] = 0.1 + 0.8*frandom(); |
184 |
greg |
2.26 |
} |
185 |
greg |
2.46 |
SDsquare2disk(spt, (j+spt[1])/hp->ns, (i+spt[0])/hp->ns); |
186 |
greg |
2.26 |
zd = sqrt(1. - spt[0]*spt[0] - spt[1]*spt[1]); |
187 |
|
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for (ii = 3; ii--; ) |
188 |
greg |
2.41 |
arp->rdir[ii] = spt[0]*hp->ux[ii] + |
189 |
greg |
2.26 |
spt[1]*hp->uy[ii] + |
190 |
|
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zd*hp->rp->ron[ii]; |
191 |
greg |
2.41 |
checknorm(arp->rdir); |
192 |
greg |
2.46 |
dimlist[ndims++] = ambndx(hp,i,j) + 90171; |
193 |
greg |
2.43 |
rayvalue(arp); /* evaluate ray */ |
194 |
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ndims--; /* apply coefficient */ |
195 |
|
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multcolor(arp->rcol, arp->rcoef); |
196 |
greg |
2.41 |
return(1); |
197 |
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} |
198 |
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199 |
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200 |
|
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static AMBSAMP * |
201 |
greg |
2.43 |
ambsample( /* initial ambient division sample */ |
202 |
greg |
2.41 |
AMBHEMI *hp, |
203 |
|
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int i, |
204 |
|
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int j |
205 |
|
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) |
206 |
|
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{ |
207 |
greg |
2.43 |
AMBSAMP *ap = &ambsam(hp,i,j); |
208 |
greg |
2.41 |
RAY ar; |
209 |
|
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/* generate hemispherical sample */ |
210 |
greg |
2.43 |
if (!getambsamp(&ar, hp, i, j, 0)) |
211 |
greg |
2.41 |
goto badsample; |
212 |
greg |
2.34 |
/* limit vertex distance */ |
213 |
|
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if (ar.rt > 10.0*thescene.cusize) |
214 |
|
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ar.rt = 10.0*thescene.cusize; |
215 |
greg |
2.31 |
else if (ar.rt <= FTINY) /* should never happen! */ |
216 |
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goto badsample; |
217 |
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VSUM(ap->p, ar.rorg, ar.rdir, ar.rt); |
218 |
greg |
2.26 |
copycolor(ap->v, ar.rcol); |
219 |
greg |
2.28 |
return(ap); |
220 |
greg |
2.31 |
badsample: |
221 |
|
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setcolor(ap->v, 0., 0., 0.); |
222 |
|
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VCOPY(ap->p, hp->rp->rop); |
223 |
|
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return(NULL); |
224 |
greg |
2.26 |
} |
225 |
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|
226 |
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|
227 |
greg |
2.41 |
/* Estimate errors based on ambient division differences */ |
228 |
|
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static float * |
229 |
|
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getambdiffs(AMBHEMI *hp) |
230 |
|
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{ |
231 |
greg |
2.45 |
float *earr = (float *)calloc(hp->ns*hp->ns, sizeof(float)); |
232 |
greg |
2.41 |
float *ep; |
233 |
greg |
2.42 |
AMBSAMP *ap; |
234 |
greg |
2.41 |
double b, d2; |
235 |
|
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int i, j; |
236 |
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|
237 |
|
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if (earr == NULL) /* out of memory? */ |
238 |
|
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return(NULL); |
239 |
|
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/* compute squared neighbor diffs */ |
240 |
greg |
2.42 |
for (ap = hp->sa, ep = earr, i = 0; i < hp->ns; i++) |
241 |
|
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for (j = 0; j < hp->ns; j++, ap++, ep++) { |
242 |
|
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b = bright(ap[0].v); |
243 |
greg |
2.41 |
if (i) { /* from above */ |
244 |
greg |
2.42 |
d2 = b - bright(ap[-hp->ns].v); |
245 |
greg |
2.41 |
d2 *= d2; |
246 |
|
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ep[0] += d2; |
247 |
|
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ep[-hp->ns] += d2; |
248 |
|
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} |
249 |
|
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if (j) { /* from behind */ |
250 |
greg |
2.42 |
d2 = b - bright(ap[-1].v); |
251 |
greg |
2.41 |
d2 *= d2; |
252 |
|
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ep[0] += d2; |
253 |
|
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ep[-1] += d2; |
254 |
|
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} |
255 |
|
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} |
256 |
|
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/* correct for number of neighbors */ |
257 |
|
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earr[0] *= 2.f; |
258 |
|
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earr[hp->ns-1] *= 2.f; |
259 |
|
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earr[(hp->ns-1)*hp->ns] *= 2.f; |
260 |
|
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earr[(hp->ns-1)*hp->ns + hp->ns-1] *= 2.f; |
261 |
|
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for (i = 1; i < hp->ns-1; i++) { |
262 |
|
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earr[i*hp->ns] *= 4./3.; |
263 |
|
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earr[i*hp->ns + hp->ns-1] *= 4./3.; |
264 |
|
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} |
265 |
|
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for (j = 1; j < hp->ns-1; j++) { |
266 |
|
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earr[j] *= 4./3.; |
267 |
|
|
earr[(hp->ns-1)*hp->ns + j] *= 4./3.; |
268 |
|
|
} |
269 |
|
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return(earr); |
270 |
|
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} |
271 |
|
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|
272 |
|
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|
273 |
greg |
2.43 |
/* Perform super-sampling on hemisphere (introduces bias) */ |
274 |
greg |
2.41 |
static void |
275 |
|
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ambsupersamp(double acol[3], AMBHEMI *hp, int cnt) |
276 |
|
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{ |
277 |
|
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float *earr = getambdiffs(hp); |
278 |
|
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double e2sum = 0; |
279 |
|
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AMBSAMP *ap; |
280 |
|
|
RAY ar; |
281 |
|
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COLOR asum; |
282 |
|
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float *ep; |
283 |
|
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int i, j, n; |
284 |
|
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|
285 |
|
|
if (earr == NULL) /* just skip calc. if no memory */ |
286 |
|
|
return; |
287 |
|
|
/* add up estimated variances */ |
288 |
|
|
for (ep = earr + hp->ns*hp->ns; ep-- > earr; ) |
289 |
|
|
e2sum += *ep; |
290 |
|
|
ep = earr; /* perform super-sampling */ |
291 |
|
|
for (ap = hp->sa, i = 0; i < hp->ns; i++) |
292 |
|
|
for (j = 0; j < hp->ns; j++, ap++) { |
293 |
|
|
int nss = *ep/e2sum*cnt + frandom(); |
294 |
|
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setcolor(asum, 0., 0., 0.); |
295 |
|
|
for (n = 1; n <= nss; n++) { |
296 |
greg |
2.43 |
if (!getambsamp(&ar, hp, i, j, n)) { |
297 |
greg |
2.41 |
nss = n-1; |
298 |
|
|
break; |
299 |
|
|
} |
300 |
|
|
addcolor(asum, ar.rcol); |
301 |
|
|
} |
302 |
|
|
if (nss) { /* update returned ambient value */ |
303 |
|
|
const double ssf = 1./(nss + 1); |
304 |
|
|
for (n = 3; n--; ) |
305 |
|
|
acol[n] += ssf*colval(asum,n) + |
306 |
|
|
(ssf - 1.)*colval(ap->v,n); |
307 |
|
|
} |
308 |
|
|
e2sum -= *ep++; /* update remainders */ |
309 |
|
|
cnt -= nss; |
310 |
|
|
} |
311 |
|
|
free(earr); |
312 |
|
|
} |
313 |
|
|
|
314 |
|
|
|
315 |
greg |
2.46 |
/* Compute vertex flags, indicating farthest in each direction */ |
316 |
|
|
static uby8 * |
317 |
|
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vertex_flags(AMBHEMI *hp) |
318 |
|
|
{ |
319 |
|
|
uby8 *vflags = (uby8 *)calloc(hp->ns*hp->ns, sizeof(uby8)); |
320 |
|
|
double *dist2a = (double *)malloc(sizeof(double)*hp->ns); |
321 |
|
|
uby8 *vf; |
322 |
|
|
int i, j; |
323 |
|
|
|
324 |
|
|
if ((vflags == NULL) | (dist2a == NULL)) |
325 |
|
|
error(SYSTEM, "out of memory in vertex_flags()"); |
326 |
|
|
vf = vflags; /* compute distances along first row */ |
327 |
|
|
for (j = 0; j < hp->ns; j++) { |
328 |
|
|
dist2a[j] = dist2(ambsam(hp,0,j).p, hp->rp->rop); |
329 |
|
|
++vf; |
330 |
|
|
if (!j) continue; |
331 |
|
|
if (dist2a[j] >= dist2a[j-1]) |
332 |
|
|
vf[0] |= 1<<VDB_x; |
333 |
|
|
else |
334 |
|
|
vf[-1] |= 1<<VDB_X; |
335 |
|
|
} |
336 |
|
|
/* flag subsequent rows */ |
337 |
|
|
for (i = 1; i < hp->ns; i++) { |
338 |
|
|
double d2n = dist2(ambsam(hp,i,0).p, hp->rp->rop); |
339 |
|
|
for (j = 0; j < hp->ns-1; j++) { |
340 |
|
|
double d2 = d2n; |
341 |
|
|
if (d2 >= dist2a[j]) /* row before */ |
342 |
|
|
vf[0] |= 1<<VDB_y; |
343 |
|
|
else |
344 |
|
|
vf[-hp->ns] |= 1<<VDB_Y; |
345 |
|
|
dist2a[j] = d2n; |
346 |
|
|
if (d2 >= dist2a[j+1]) /* diagonal we care about */ |
347 |
|
|
vf[0] |= 1<<VDB_Xy; |
348 |
|
|
else |
349 |
|
|
vf[1-hp->ns] |= 1<<VDB_xY; |
350 |
|
|
d2n = dist2(ambsam(hp,i,j+1).p, hp->rp->rop); |
351 |
|
|
if (d2 >= d2n) /* column after */ |
352 |
|
|
vf[0] |= 1<<VDB_X; |
353 |
|
|
else |
354 |
|
|
vf[1] |= 1<<VDB_x; |
355 |
|
|
++vf; |
356 |
|
|
} |
357 |
|
|
if (d2n >= dist2a[j]) /* final column edge */ |
358 |
|
|
vf[0] |= 1<<VDB_y; |
359 |
|
|
else |
360 |
|
|
vf[-hp->ns] |= 1<<VDB_Y; |
361 |
|
|
dist2a[j] = d2n; |
362 |
|
|
++vf; |
363 |
|
|
} |
364 |
|
|
free(dist2a); |
365 |
|
|
return(vflags); |
366 |
|
|
} |
367 |
|
|
|
368 |
|
|
|
369 |
|
|
/* Return brightness of farthest ambient sample */ |
370 |
|
|
static double |
371 |
|
|
back_ambval(AMBHEMI *hp, int i, int j, int dbit1, int dbit2, const uby8 *vflags) |
372 |
|
|
{ |
373 |
|
|
const int v0 = ambndx(hp,i,j); |
374 |
|
|
const int tflags = (1<<dbit1 | 1<<dbit2); |
375 |
|
|
int v1, v2; |
376 |
|
|
|
377 |
|
|
if ((vflags[v0] & tflags) == tflags) /* is v0 the farthest? */ |
378 |
|
|
return(colval(hp->sa[v0].v,CIEY)); |
379 |
|
|
v1 = adjacent_verti(hp, i, j, dbit1); |
380 |
|
|
if (vflags[v0] & 1<<dbit2) /* v1 farthest if v0>v2 */ |
381 |
|
|
return(colval(hp->sa[v1].v,CIEY)); |
382 |
|
|
v2 = adjacent_verti(hp, i, j, dbit2); |
383 |
|
|
if (vflags[v0] & 1<<dbit1) /* v2 farthest if v0>v1 */ |
384 |
|
|
return(colval(hp->sa[v2].v,CIEY)); |
385 |
|
|
/* else check if v1>v2 */ |
386 |
|
|
if (vflags[v1] & 1<<vdb_edge(dbit1,dbit2)) |
387 |
|
|
return(colval(hp->sa[v1].v,CIEY)); |
388 |
|
|
return(colval(hp->sa[v2].v,CIEY)); |
389 |
|
|
} |
390 |
|
|
|
391 |
|
|
|
392 |
greg |
2.27 |
/* Compute vectors and coefficients for Hessian/gradient calcs */ |
393 |
|
|
static void |
394 |
greg |
2.46 |
comp_fftri(FFTRI *ftp, AMBHEMI *hp, int i, int j, int dbit, const uby8 *vflags) |
395 |
greg |
2.27 |
{ |
396 |
greg |
2.46 |
const int i0 = ambndx(hp,i,j); |
397 |
|
|
double rdot_cp, dot_e, dot_er, rdot_r, rdot_r1, J2; |
398 |
|
|
int i1, ii; |
399 |
|
|
|
400 |
|
|
ftp->valid = 0; /* check if we can skip this edge */ |
401 |
|
|
ii = adjacent_trifl[dbit]; |
402 |
|
|
if ((vflags[i0] & ii) == ii) /* cancels if vertex used as value */ |
403 |
|
|
return; |
404 |
|
|
i1 = adjacent_verti(hp, i, j, dbit); |
405 |
|
|
ii = adjacent_trifl[VDB_OPP(dbit)]; |
406 |
|
|
if ((vflags[i1] & ii) == ii) /* on either end (for both triangles) */ |
407 |
|
|
return; |
408 |
|
|
/* else go ahead with calculation */ |
409 |
|
|
VSUB(ftp->r_i, hp->sa[i0].p, hp->rp->rop); |
410 |
|
|
VSUB(ftp->r_i1, hp->sa[i1].p, hp->rp->rop); |
411 |
|
|
VSUB(ftp->e_i, hp->sa[i1].p, hp->sa[i0].p); |
412 |
greg |
2.35 |
VCROSS(ftp->rcp, ftp->r_i, ftp->r_i1); |
413 |
|
|
rdot_cp = 1.0/DOT(ftp->rcp,ftp->rcp); |
414 |
greg |
2.27 |
dot_e = DOT(ftp->e_i,ftp->e_i); |
415 |
|
|
dot_er = DOT(ftp->e_i, ftp->r_i); |
416 |
greg |
2.32 |
rdot_r = 1.0/DOT(ftp->r_i,ftp->r_i); |
417 |
|
|
rdot_r1 = 1.0/DOT(ftp->r_i1,ftp->r_i1); |
418 |
|
|
ftp->I1 = acos( DOT(ftp->r_i, ftp->r_i1) * sqrt(rdot_r*rdot_r1) ) * |
419 |
greg |
2.35 |
sqrt( rdot_cp ); |
420 |
greg |
2.32 |
ftp->I2 = ( DOT(ftp->e_i, ftp->r_i1)*rdot_r1 - dot_er*rdot_r + |
421 |
greg |
2.35 |
dot_e*ftp->I1 )*0.5*rdot_cp; |
422 |
greg |
2.32 |
J2 = ( 0.5*(rdot_r - rdot_r1) - dot_er*ftp->I2 ) / dot_e; |
423 |
greg |
2.46 |
for (ii = 3; ii--; ) |
424 |
|
|
ftp->rI2_eJ2[ii] = ftp->I2*ftp->r_i[ii] + J2*ftp->e_i[ii]; |
425 |
|
|
ftp->valid++; |
426 |
greg |
2.27 |
} |
427 |
|
|
|
428 |
|
|
|
429 |
greg |
2.28 |
/* Compose 3x3 matrix from two vectors */ |
430 |
greg |
2.27 |
static void |
431 |
|
|
compose_matrix(FVECT mat[3], FVECT va, FVECT vb) |
432 |
|
|
{ |
433 |
|
|
mat[0][0] = 2.0*va[0]*vb[0]; |
434 |
|
|
mat[1][1] = 2.0*va[1]*vb[1]; |
435 |
|
|
mat[2][2] = 2.0*va[2]*vb[2]; |
436 |
|
|
mat[0][1] = mat[1][0] = va[0]*vb[1] + va[1]*vb[0]; |
437 |
|
|
mat[0][2] = mat[2][0] = va[0]*vb[2] + va[2]*vb[0]; |
438 |
|
|
mat[1][2] = mat[2][1] = va[1]*vb[2] + va[2]*vb[1]; |
439 |
|
|
} |
440 |
|
|
|
441 |
|
|
|
442 |
|
|
/* Compute partial 3x3 Hessian matrix for edge */ |
443 |
|
|
static void |
444 |
|
|
comp_hessian(FVECT hess[3], FFTRI *ftp, FVECT nrm) |
445 |
|
|
{ |
446 |
greg |
2.35 |
FVECT ncp; |
447 |
greg |
2.27 |
FVECT m1[3], m2[3], m3[3], m4[3]; |
448 |
|
|
double d1, d2, d3, d4; |
449 |
|
|
double I3, J3, K3; |
450 |
|
|
int i, j; |
451 |
greg |
2.46 |
|
452 |
|
|
if (!ftp->valid) { /* preemptive test */ |
453 |
|
|
memset(hess, 0, sizeof(FVECT)*3); |
454 |
|
|
return; |
455 |
|
|
} |
456 |
greg |
2.27 |
/* compute intermediate coefficients */ |
457 |
|
|
d1 = 1.0/DOT(ftp->r_i,ftp->r_i); |
458 |
|
|
d2 = 1.0/DOT(ftp->r_i1,ftp->r_i1); |
459 |
|
|
d3 = 1.0/DOT(ftp->e_i,ftp->e_i); |
460 |
|
|
d4 = DOT(ftp->e_i, ftp->r_i); |
461 |
greg |
2.35 |
I3 = ( DOT(ftp->e_i, ftp->r_i1)*d2*d2 - d4*d1*d1 + 3.0/d3*ftp->I2 ) |
462 |
|
|
/ ( 4.0*DOT(ftp->rcp,ftp->rcp) ); |
463 |
greg |
2.27 |
J3 = 0.25*d3*(d1*d1 - d2*d2) - d4*d3*I3; |
464 |
|
|
K3 = d3*(ftp->I2 - I3/d1 - 2.0*d4*J3); |
465 |
|
|
/* intermediate matrices */ |
466 |
greg |
2.35 |
VCROSS(ncp, nrm, ftp->e_i); |
467 |
|
|
compose_matrix(m1, ncp, ftp->rI2_eJ2); |
468 |
greg |
2.27 |
compose_matrix(m2, ftp->r_i, ftp->r_i); |
469 |
|
|
compose_matrix(m3, ftp->e_i, ftp->e_i); |
470 |
|
|
compose_matrix(m4, ftp->r_i, ftp->e_i); |
471 |
greg |
2.35 |
d1 = DOT(nrm, ftp->rcp); |
472 |
greg |
2.27 |
d2 = -d1*ftp->I2; |
473 |
|
|
d1 *= 2.0; |
474 |
|
|
for (i = 3; i--; ) /* final matrix sum */ |
475 |
|
|
for (j = 3; j--; ) { |
476 |
|
|
hess[i][j] = m1[i][j] + d1*( I3*m2[i][j] + K3*m3[i][j] + |
477 |
|
|
2.0*J3*m4[i][j] ); |
478 |
|
|
hess[i][j] += d2*(i==j); |
479 |
greg |
2.46 |
hess[i][j] *= -1.0/PI; |
480 |
greg |
2.27 |
} |
481 |
|
|
} |
482 |
|
|
|
483 |
|
|
|
484 |
|
|
/* Reverse hessian calculation result for edge in other direction */ |
485 |
|
|
static void |
486 |
|
|
rev_hessian(FVECT hess[3]) |
487 |
|
|
{ |
488 |
|
|
int i; |
489 |
|
|
|
490 |
|
|
for (i = 3; i--; ) { |
491 |
|
|
hess[i][0] = -hess[i][0]; |
492 |
|
|
hess[i][1] = -hess[i][1]; |
493 |
|
|
hess[i][2] = -hess[i][2]; |
494 |
|
|
} |
495 |
|
|
} |
496 |
|
|
|
497 |
|
|
|
498 |
|
|
/* Add to radiometric Hessian from the given triangle */ |
499 |
|
|
static void |
500 |
|
|
add2hessian(FVECT hess[3], FVECT ehess1[3], |
501 |
greg |
2.46 |
FVECT ehess2[3], FVECT ehess3[3], double v) |
502 |
greg |
2.27 |
{ |
503 |
|
|
int i, j; |
504 |
|
|
|
505 |
|
|
for (i = 3; i--; ) |
506 |
|
|
for (j = 3; j--; ) |
507 |
|
|
hess[i][j] += v*( ehess1[i][j] + ehess2[i][j] + ehess3[i][j] ); |
508 |
|
|
} |
509 |
|
|
|
510 |
|
|
|
511 |
|
|
/* Compute partial displacement form factor gradient for edge */ |
512 |
|
|
static void |
513 |
|
|
comp_gradient(FVECT grad, FFTRI *ftp, FVECT nrm) |
514 |
|
|
{ |
515 |
greg |
2.35 |
FVECT ncp; |
516 |
greg |
2.27 |
double f1; |
517 |
|
|
int i; |
518 |
|
|
|
519 |
greg |
2.46 |
if (!ftp->valid) { /* preemptive test */ |
520 |
|
|
memset(grad, 0, sizeof(FVECT)); |
521 |
|
|
return; |
522 |
|
|
} |
523 |
greg |
2.35 |
f1 = 2.0*DOT(nrm, ftp->rcp); |
524 |
|
|
VCROSS(ncp, nrm, ftp->e_i); |
525 |
greg |
2.27 |
for (i = 3; i--; ) |
526 |
greg |
2.46 |
grad[i] = (0.5/PI)*( ftp->I1*ncp[i] + f1*ftp->rI2_eJ2[i] ); |
527 |
greg |
2.27 |
} |
528 |
|
|
|
529 |
|
|
|
530 |
|
|
/* Reverse gradient calculation result for edge in other direction */ |
531 |
|
|
static void |
532 |
|
|
rev_gradient(FVECT grad) |
533 |
|
|
{ |
534 |
|
|
grad[0] = -grad[0]; |
535 |
|
|
grad[1] = -grad[1]; |
536 |
|
|
grad[2] = -grad[2]; |
537 |
|
|
} |
538 |
|
|
|
539 |
|
|
|
540 |
|
|
/* Add to displacement gradient from the given triangle */ |
541 |
|
|
static void |
542 |
greg |
2.46 |
add2gradient(FVECT grad, FVECT egrad1, FVECT egrad2, FVECT egrad3, double v) |
543 |
greg |
2.27 |
{ |
544 |
|
|
int i; |
545 |
|
|
|
546 |
|
|
for (i = 3; i--; ) |
547 |
|
|
grad[i] += v*( egrad1[i] + egrad2[i] + egrad3[i] ); |
548 |
|
|
} |
549 |
|
|
|
550 |
|
|
|
551 |
|
|
/* Compute anisotropic radii and eigenvector directions */ |
552 |
|
|
static int |
553 |
|
|
eigenvectors(FVECT uv[2], float ra[2], FVECT hessian[3]) |
554 |
|
|
{ |
555 |
|
|
double hess2[2][2]; |
556 |
|
|
FVECT a, b; |
557 |
|
|
double evalue[2], slope1, xmag1; |
558 |
|
|
int i; |
559 |
|
|
/* project Hessian to sample plane */ |
560 |
|
|
for (i = 3; i--; ) { |
561 |
|
|
a[i] = DOT(hessian[i], uv[0]); |
562 |
|
|
b[i] = DOT(hessian[i], uv[1]); |
563 |
|
|
} |
564 |
|
|
hess2[0][0] = DOT(uv[0], a); |
565 |
|
|
hess2[0][1] = DOT(uv[0], b); |
566 |
|
|
hess2[1][0] = DOT(uv[1], a); |
567 |
|
|
hess2[1][1] = DOT(uv[1], b); |
568 |
greg |
2.38 |
/* compute eigenvalue(s) */ |
569 |
|
|
i = quadratic(evalue, 1.0, -hess2[0][0]-hess2[1][1], |
570 |
|
|
hess2[0][0]*hess2[1][1]-hess2[0][1]*hess2[1][0]); |
571 |
|
|
if (i == 1) /* double-root (circle) */ |
572 |
|
|
evalue[1] = evalue[0]; |
573 |
|
|
if (!i || ((evalue[0] = fabs(evalue[0])) <= FTINY*FTINY) | |
574 |
greg |
2.35 |
((evalue[1] = fabs(evalue[1])) <= FTINY*FTINY) ) |
575 |
greg |
2.27 |
error(INTERNAL, "bad eigenvalue calculation"); |
576 |
|
|
|
577 |
|
|
if (evalue[0] > evalue[1]) { |
578 |
greg |
2.29 |
ra[0] = sqrt(sqrt(4.0/evalue[0])); |
579 |
|
|
ra[1] = sqrt(sqrt(4.0/evalue[1])); |
580 |
greg |
2.27 |
slope1 = evalue[1]; |
581 |
|
|
} else { |
582 |
greg |
2.29 |
ra[0] = sqrt(sqrt(4.0/evalue[1])); |
583 |
|
|
ra[1] = sqrt(sqrt(4.0/evalue[0])); |
584 |
greg |
2.27 |
slope1 = evalue[0]; |
585 |
|
|
} |
586 |
|
|
/* compute unit eigenvectors */ |
587 |
|
|
if (fabs(hess2[0][1]) <= FTINY) |
588 |
|
|
return; /* uv OK as is */ |
589 |
|
|
slope1 = (slope1 - hess2[0][0]) / hess2[0][1]; |
590 |
|
|
xmag1 = sqrt(1.0/(1.0 + slope1*slope1)); |
591 |
|
|
for (i = 3; i--; ) { |
592 |
|
|
b[i] = xmag1*uv[0][i] + slope1*xmag1*uv[1][i]; |
593 |
|
|
a[i] = slope1*xmag1*uv[0][i] - xmag1*uv[1][i]; |
594 |
|
|
} |
595 |
|
|
VCOPY(uv[0], a); |
596 |
|
|
VCOPY(uv[1], b); |
597 |
|
|
} |
598 |
|
|
|
599 |
|
|
|
600 |
greg |
2.26 |
static void |
601 |
|
|
ambHessian( /* anisotropic radii & pos. gradient */ |
602 |
|
|
AMBHEMI *hp, |
603 |
|
|
FVECT uv[2], /* returned */ |
604 |
greg |
2.28 |
float ra[2], /* returned (optional) */ |
605 |
|
|
float pg[2] /* returned (optional) */ |
606 |
greg |
2.26 |
) |
607 |
|
|
{ |
608 |
greg |
2.27 |
static char memerrmsg[] = "out of memory in ambHessian()"; |
609 |
|
|
FVECT (*hessrow)[3] = NULL; |
610 |
|
|
FVECT *gradrow = NULL; |
611 |
greg |
2.46 |
uby8 *vflags; |
612 |
greg |
2.27 |
FVECT hessian[3]; |
613 |
|
|
FVECT gradient; |
614 |
|
|
FFTRI fftr; |
615 |
|
|
int i, j; |
616 |
|
|
/* be sure to assign unit vectors */ |
617 |
|
|
VCOPY(uv[0], hp->ux); |
618 |
|
|
VCOPY(uv[1], hp->uy); |
619 |
|
|
/* clock-wise vertex traversal from sample POV */ |
620 |
|
|
if (ra != NULL) { /* initialize Hessian row buffer */ |
621 |
greg |
2.28 |
hessrow = (FVECT (*)[3])malloc(sizeof(FVECT)*3*(hp->ns-1)); |
622 |
greg |
2.27 |
if (hessrow == NULL) |
623 |
|
|
error(SYSTEM, memerrmsg); |
624 |
|
|
memset(hessian, 0, sizeof(hessian)); |
625 |
|
|
} else if (pg == NULL) /* bogus call? */ |
626 |
|
|
return; |
627 |
|
|
if (pg != NULL) { /* initialize form factor row buffer */ |
628 |
greg |
2.28 |
gradrow = (FVECT *)malloc(sizeof(FVECT)*(hp->ns-1)); |
629 |
greg |
2.27 |
if (gradrow == NULL) |
630 |
|
|
error(SYSTEM, memerrmsg); |
631 |
|
|
memset(gradient, 0, sizeof(gradient)); |
632 |
|
|
} |
633 |
greg |
2.46 |
/* get vertex position flags */ |
634 |
|
|
vflags = vertex_flags(hp); |
635 |
greg |
2.27 |
/* compute first row of edges */ |
636 |
|
|
for (j = 0; j < hp->ns-1; j++) { |
637 |
greg |
2.46 |
comp_fftri(&fftr, hp, 0, j, VDB_X, vflags); |
638 |
greg |
2.27 |
if (hessrow != NULL) |
639 |
|
|
comp_hessian(hessrow[j], &fftr, hp->rp->ron); |
640 |
|
|
if (gradrow != NULL) |
641 |
|
|
comp_gradient(gradrow[j], &fftr, hp->rp->ron); |
642 |
|
|
} |
643 |
|
|
/* sum each row of triangles */ |
644 |
|
|
for (i = 0; i < hp->ns-1; i++) { |
645 |
|
|
FVECT hesscol[3]; /* compute first vertical edge */ |
646 |
|
|
FVECT gradcol; |
647 |
greg |
2.46 |
comp_fftri(&fftr, hp, i, 0, VDB_Y, vflags); |
648 |
greg |
2.27 |
if (hessrow != NULL) |
649 |
|
|
comp_hessian(hesscol, &fftr, hp->rp->ron); |
650 |
|
|
if (gradrow != NULL) |
651 |
|
|
comp_gradient(gradcol, &fftr, hp->rp->ron); |
652 |
|
|
for (j = 0; j < hp->ns-1; j++) { |
653 |
|
|
FVECT hessdia[3]; /* compute triangle contributions */ |
654 |
|
|
FVECT graddia; |
655 |
greg |
2.46 |
double backg; |
656 |
|
|
backg = back_ambval(hp, i, j, VDB_X, VDB_Y, vflags); |
657 |
greg |
2.27 |
/* diagonal (inner) edge */ |
658 |
greg |
2.46 |
comp_fftri(&fftr, hp, i, j+1, VDB_xY, vflags); |
659 |
greg |
2.27 |
if (hessrow != NULL) { |
660 |
|
|
comp_hessian(hessdia, &fftr, hp->rp->ron); |
661 |
|
|
rev_hessian(hesscol); |
662 |
|
|
add2hessian(hessian, hessrow[j], hessdia, hesscol, backg); |
663 |
|
|
} |
664 |
greg |
2.39 |
if (gradrow != NULL) { |
665 |
greg |
2.27 |
comp_gradient(graddia, &fftr, hp->rp->ron); |
666 |
|
|
rev_gradient(gradcol); |
667 |
|
|
add2gradient(gradient, gradrow[j], graddia, gradcol, backg); |
668 |
|
|
} |
669 |
|
|
/* initialize edge in next row */ |
670 |
greg |
2.46 |
comp_fftri(&fftr, hp, i+1, j+1, VDB_x, vflags); |
671 |
greg |
2.27 |
if (hessrow != NULL) |
672 |
|
|
comp_hessian(hessrow[j], &fftr, hp->rp->ron); |
673 |
|
|
if (gradrow != NULL) |
674 |
|
|
comp_gradient(gradrow[j], &fftr, hp->rp->ron); |
675 |
|
|
/* new column edge & paired triangle */ |
676 |
greg |
2.46 |
backg = back_ambval(hp, i+1, j+1, VDB_x, VDB_y, vflags); |
677 |
|
|
comp_fftri(&fftr, hp, i, j+1, VDB_Y, vflags); |
678 |
greg |
2.27 |
if (hessrow != NULL) { |
679 |
|
|
comp_hessian(hesscol, &fftr, hp->rp->ron); |
680 |
|
|
rev_hessian(hessdia); |
681 |
|
|
add2hessian(hessian, hessrow[j], hessdia, hesscol, backg); |
682 |
|
|
if (i < hp->ns-2) |
683 |
|
|
rev_hessian(hessrow[j]); |
684 |
|
|
} |
685 |
|
|
if (gradrow != NULL) { |
686 |
|
|
comp_gradient(gradcol, &fftr, hp->rp->ron); |
687 |
|
|
rev_gradient(graddia); |
688 |
|
|
add2gradient(gradient, gradrow[j], graddia, gradcol, backg); |
689 |
|
|
if (i < hp->ns-2) |
690 |
|
|
rev_gradient(gradrow[j]); |
691 |
|
|
} |
692 |
|
|
} |
693 |
|
|
} |
694 |
|
|
/* release row buffers */ |
695 |
|
|
if (hessrow != NULL) free(hessrow); |
696 |
|
|
if (gradrow != NULL) free(gradrow); |
697 |
greg |
2.46 |
free(vflags); |
698 |
greg |
2.27 |
|
699 |
|
|
if (ra != NULL) /* extract eigenvectors & radii */ |
700 |
|
|
eigenvectors(uv, ra, hessian); |
701 |
greg |
2.32 |
if (pg != NULL) { /* tangential position gradient */ |
702 |
|
|
pg[0] = DOT(gradient, uv[0]); |
703 |
|
|
pg[1] = DOT(gradient, uv[1]); |
704 |
greg |
2.27 |
} |
705 |
|
|
} |
706 |
|
|
|
707 |
|
|
|
708 |
|
|
/* Compute direction gradient from a hemispherical sampling */ |
709 |
|
|
static void |
710 |
|
|
ambdirgrad(AMBHEMI *hp, FVECT uv[2], float dg[2]) |
711 |
|
|
{ |
712 |
greg |
2.41 |
AMBSAMP *ap; |
713 |
|
|
double dgsum[2]; |
714 |
|
|
int n; |
715 |
|
|
FVECT vd; |
716 |
|
|
double gfact; |
717 |
greg |
2.27 |
|
718 |
greg |
2.29 |
dgsum[0] = dgsum[1] = 0.0; /* sum values times -tan(theta) */ |
719 |
greg |
2.27 |
for (ap = hp->sa, n = hp->ns*hp->ns; n--; ap++) { |
720 |
|
|
/* use vector for azimuth + 90deg */ |
721 |
|
|
VSUB(vd, ap->p, hp->rp->rop); |
722 |
greg |
2.29 |
/* brightness over cosine factor */ |
723 |
|
|
gfact = colval(ap->v,CIEY) / DOT(hp->rp->ron, vd); |
724 |
greg |
2.40 |
/* sine = proj_radius/vd_length */ |
725 |
|
|
dgsum[0] -= DOT(uv[1], vd) * gfact; |
726 |
|
|
dgsum[1] += DOT(uv[0], vd) * gfact; |
727 |
greg |
2.26 |
} |
728 |
greg |
2.29 |
dg[0] = dgsum[0] / (hp->ns*hp->ns); |
729 |
|
|
dg[1] = dgsum[1] / (hp->ns*hp->ns); |
730 |
greg |
2.26 |
} |
731 |
|
|
|
732 |
greg |
2.27 |
|
733 |
greg |
2.26 |
int |
734 |
|
|
doambient( /* compute ambient component */ |
735 |
|
|
COLOR rcol, /* input/output color */ |
736 |
|
|
RAY *r, |
737 |
|
|
double wt, |
738 |
greg |
2.27 |
FVECT uv[2], /* returned (optional) */ |
739 |
|
|
float ra[2], /* returned (optional) */ |
740 |
|
|
float pg[2], /* returned (optional) */ |
741 |
|
|
float dg[2] /* returned (optional) */ |
742 |
greg |
2.26 |
) |
743 |
|
|
{ |
744 |
greg |
2.41 |
AMBHEMI *hp = inithemi(rcol, r, wt); |
745 |
greg |
2.45 |
int cnt; |
746 |
greg |
2.41 |
FVECT my_uv[2]; |
747 |
|
|
double d, K, acol[3]; |
748 |
|
|
AMBSAMP *ap; |
749 |
|
|
int i, j; |
750 |
greg |
2.28 |
/* check/initialize */ |
751 |
|
|
if (hp == NULL) |
752 |
greg |
2.26 |
return(0); |
753 |
|
|
if (uv != NULL) |
754 |
|
|
memset(uv, 0, sizeof(FVECT)*2); |
755 |
|
|
if (ra != NULL) |
756 |
|
|
ra[0] = ra[1] = 0.0; |
757 |
|
|
if (pg != NULL) |
758 |
|
|
pg[0] = pg[1] = 0.0; |
759 |
|
|
if (dg != NULL) |
760 |
|
|
dg[0] = dg[1] = 0.0; |
761 |
|
|
/* sample the hemisphere */ |
762 |
|
|
acol[0] = acol[1] = acol[2] = 0.0; |
763 |
greg |
2.45 |
cnt = 0; |
764 |
greg |
2.27 |
for (i = hp->ns; i--; ) |
765 |
|
|
for (j = hp->ns; j--; ) |
766 |
greg |
2.28 |
if ((ap = ambsample(hp, i, j)) != NULL) { |
767 |
greg |
2.26 |
addcolor(acol, ap->v); |
768 |
|
|
++cnt; |
769 |
|
|
} |
770 |
|
|
if (!cnt) { |
771 |
|
|
setcolor(rcol, 0.0, 0.0, 0.0); |
772 |
|
|
free(hp); |
773 |
|
|
return(0); /* no valid samples */ |
774 |
|
|
} |
775 |
greg |
2.41 |
if (cnt < hp->ns*hp->ns) { /* incomplete sampling? */ |
776 |
|
|
copycolor(rcol, acol); |
777 |
|
|
free(hp); |
778 |
|
|
return(-1); /* return value w/o Hessian */ |
779 |
|
|
} |
780 |
|
|
cnt = ambssamp*wt + 0.5; /* perform super-sampling? */ |
781 |
|
|
if (cnt > 0) |
782 |
|
|
ambsupersamp(acol, hp, cnt); |
783 |
greg |
2.29 |
copycolor(rcol, acol); /* final indirect irradiance/PI */ |
784 |
greg |
2.41 |
if ((ra == NULL) & (pg == NULL) & (dg == NULL)) { |
785 |
greg |
2.26 |
free(hp); |
786 |
|
|
return(-1); /* no radius or gradient calc. */ |
787 |
|
|
} |
788 |
greg |
2.45 |
if ((d = bright(acol)) > FTINY) { /* normalize Y values */ |
789 |
|
|
d = 0.99*(hp->ns*hp->ns)/d; |
790 |
greg |
2.38 |
K = 0.01; |
791 |
greg |
2.45 |
} else { /* or fall back on geometric Hessian */ |
792 |
greg |
2.38 |
K = 1.0; |
793 |
|
|
pg = NULL; |
794 |
|
|
dg = NULL; |
795 |
|
|
} |
796 |
greg |
2.29 |
ap = hp->sa; /* relative Y channel from here on... */ |
797 |
greg |
2.26 |
for (i = hp->ns*hp->ns; i--; ap++) |
798 |
greg |
2.38 |
colval(ap->v,CIEY) = bright(ap->v)*d + K; |
799 |
greg |
2.26 |
|
800 |
|
|
if (uv == NULL) /* make sure we have axis pointers */ |
801 |
|
|
uv = my_uv; |
802 |
|
|
/* compute radii & pos. gradient */ |
803 |
|
|
ambHessian(hp, uv, ra, pg); |
804 |
greg |
2.29 |
|
805 |
greg |
2.26 |
if (dg != NULL) /* compute direction gradient */ |
806 |
|
|
ambdirgrad(hp, uv, dg); |
807 |
greg |
2.29 |
|
808 |
greg |
2.28 |
if (ra != NULL) { /* scale/clamp radii */ |
809 |
greg |
2.35 |
if (pg != NULL) { |
810 |
|
|
if (ra[0]*(d = fabs(pg[0])) > 1.0) |
811 |
|
|
ra[0] = 1.0/d; |
812 |
|
|
if (ra[1]*(d = fabs(pg[1])) > 1.0) |
813 |
|
|
ra[1] = 1.0/d; |
814 |
|
|
if (ra[0] > ra[1]) |
815 |
|
|
ra[0] = ra[1]; |
816 |
|
|
} |
817 |
greg |
2.29 |
if (ra[0] < minarad) { |
818 |
|
|
ra[0] = minarad; |
819 |
|
|
if (ra[1] < minarad) |
820 |
|
|
ra[1] = minarad; |
821 |
|
|
} |
822 |
|
|
ra[0] *= d = 1.0/sqrt(sqrt(wt)); |
823 |
greg |
2.26 |
if ((ra[1] *= d) > 2.0*ra[0]) |
824 |
|
|
ra[1] = 2.0*ra[0]; |
825 |
greg |
2.28 |
if (ra[1] > maxarad) { |
826 |
|
|
ra[1] = maxarad; |
827 |
|
|
if (ra[0] > maxarad) |
828 |
|
|
ra[0] = maxarad; |
829 |
|
|
} |
830 |
greg |
2.35 |
if (pg != NULL) { /* cap gradient if necessary */ |
831 |
|
|
d = pg[0]*pg[0]*ra[0]*ra[0] + pg[1]*pg[1]*ra[1]*ra[1]; |
832 |
|
|
if (d > 1.0) { |
833 |
|
|
d = 1.0/sqrt(d); |
834 |
|
|
pg[0] *= d; |
835 |
|
|
pg[1] *= d; |
836 |
|
|
} |
837 |
|
|
} |
838 |
greg |
2.26 |
} |
839 |
|
|
free(hp); /* clean up and return */ |
840 |
|
|
return(1); |
841 |
|
|
} |
842 |
|
|
|
843 |
|
|
|
844 |
greg |
2.25 |
#else /* ! NEWAMB */ |
845 |
greg |
1.1 |
|
846 |
|
|
|
847 |
greg |
2.15 |
void |
848 |
greg |
2.14 |
inithemi( /* initialize sampling hemisphere */ |
849 |
greg |
2.23 |
AMBHEMI *hp, |
850 |
greg |
2.16 |
COLOR ac, |
851 |
greg |
2.14 |
RAY *r, |
852 |
|
|
double wt |
853 |
|
|
) |
854 |
greg |
1.1 |
{ |
855 |
greg |
2.16 |
double d; |
856 |
greg |
2.23 |
int i; |
857 |
greg |
2.14 |
/* set number of divisions */ |
858 |
greg |
2.16 |
if (ambacc <= FTINY && |
859 |
greg |
2.20 |
wt > (d = 0.8*intens(ac)*r->rweight/(ambdiv*minweight))) |
860 |
greg |
2.16 |
wt = d; /* avoid ray termination */ |
861 |
|
|
hp->nt = sqrt(ambdiv * wt / PI) + 0.5; |
862 |
greg |
2.14 |
i = ambacc > FTINY ? 3 : 1; /* minimum number of samples */ |
863 |
|
|
if (hp->nt < i) |
864 |
|
|
hp->nt = i; |
865 |
|
|
hp->np = PI * hp->nt + 0.5; |
866 |
|
|
/* set number of super-samples */ |
867 |
greg |
2.15 |
hp->ns = ambssamp * wt + 0.5; |
868 |
greg |
2.16 |
/* assign coefficient */ |
869 |
greg |
2.14 |
copycolor(hp->acoef, ac); |
870 |
greg |
2.16 |
d = 1.0/(hp->nt*hp->np); |
871 |
|
|
scalecolor(hp->acoef, d); |
872 |
greg |
2.14 |
/* make axes */ |
873 |
|
|
VCOPY(hp->uz, r->ron); |
874 |
|
|
hp->uy[0] = hp->uy[1] = hp->uy[2] = 0.0; |
875 |
|
|
for (i = 0; i < 3; i++) |
876 |
|
|
if (hp->uz[i] < 0.6 && hp->uz[i] > -0.6) |
877 |
|
|
break; |
878 |
|
|
if (i >= 3) |
879 |
|
|
error(CONSISTENCY, "bad ray direction in inithemi"); |
880 |
|
|
hp->uy[i] = 1.0; |
881 |
|
|
fcross(hp->ux, hp->uy, hp->uz); |
882 |
|
|
normalize(hp->ux); |
883 |
|
|
fcross(hp->uy, hp->uz, hp->ux); |
884 |
greg |
1.1 |
} |
885 |
|
|
|
886 |
|
|
|
887 |
greg |
2.9 |
int |
888 |
greg |
2.14 |
divsample( /* sample a division */ |
889 |
greg |
2.23 |
AMBSAMP *dp, |
890 |
greg |
2.14 |
AMBHEMI *h, |
891 |
|
|
RAY *r |
892 |
|
|
) |
893 |
greg |
1.1 |
{ |
894 |
|
|
RAY ar; |
895 |
greg |
1.11 |
int hlist[3]; |
896 |
|
|
double spt[2]; |
897 |
greg |
1.1 |
double xd, yd, zd; |
898 |
|
|
double b2; |
899 |
|
|
double phi; |
900 |
greg |
2.23 |
int i; |
901 |
greg |
2.15 |
/* ambient coefficient for weight */ |
902 |
greg |
2.16 |
if (ambacc > FTINY) |
903 |
|
|
setcolor(ar.rcoef, AVGREFL, AVGREFL, AVGREFL); |
904 |
|
|
else |
905 |
|
|
copycolor(ar.rcoef, h->acoef); |
906 |
greg |
2.14 |
if (rayorigin(&ar, AMBIENT, r, ar.rcoef) < 0) |
907 |
greg |
1.4 |
return(-1); |
908 |
greg |
2.17 |
if (ambacc > FTINY) { |
909 |
|
|
multcolor(ar.rcoef, h->acoef); |
910 |
|
|
scalecolor(ar.rcoef, 1./AVGREFL); |
911 |
|
|
} |
912 |
greg |
1.1 |
hlist[0] = r->rno; |
913 |
|
|
hlist[1] = dp->t; |
914 |
|
|
hlist[2] = dp->p; |
915 |
greg |
1.13 |
multisamp(spt, 2, urand(ilhash(hlist,3)+dp->n)); |
916 |
greg |
1.11 |
zd = sqrt((dp->t + spt[0])/h->nt); |
917 |
|
|
phi = 2.0*PI * (dp->p + spt[1])/h->np; |
918 |
gwlarson |
2.8 |
xd = tcos(phi) * zd; |
919 |
|
|
yd = tsin(phi) * zd; |
920 |
greg |
1.1 |
zd = sqrt(1.0 - zd*zd); |
921 |
greg |
1.2 |
for (i = 0; i < 3; i++) |
922 |
|
|
ar.rdir[i] = xd*h->ux[i] + |
923 |
|
|
yd*h->uy[i] + |
924 |
|
|
zd*h->uz[i]; |
925 |
greg |
2.22 |
checknorm(ar.rdir); |
926 |
greg |
1.2 |
dimlist[ndims++] = dp->t*h->np + dp->p + 90171; |
927 |
greg |
1.1 |
rayvalue(&ar); |
928 |
|
|
ndims--; |
929 |
greg |
2.16 |
multcolor(ar.rcol, ar.rcoef); /* apply coefficient */ |
930 |
greg |
1.1 |
addcolor(dp->v, ar.rcol); |
931 |
greg |
2.9 |
/* use rt to improve gradient calc */ |
932 |
|
|
if (ar.rt > FTINY && ar.rt < FHUGE) |
933 |
|
|
dp->r += 1.0/ar.rt; |
934 |
greg |
1.1 |
/* (re)initialize error */ |
935 |
|
|
if (dp->n++) { |
936 |
|
|
b2 = bright(dp->v)/dp->n - bright(ar.rcol); |
937 |
|
|
b2 = b2*b2 + dp->k*((dp->n-1)*(dp->n-1)); |
938 |
|
|
dp->k = b2/(dp->n*dp->n); |
939 |
|
|
} else |
940 |
|
|
dp->k = 0.0; |
941 |
greg |
1.4 |
return(0); |
942 |
greg |
1.1 |
} |
943 |
|
|
|
944 |
|
|
|
945 |
greg |
2.14 |
static int |
946 |
|
|
ambcmp( /* decreasing order */ |
947 |
|
|
const void *p1, |
948 |
|
|
const void *p2 |
949 |
|
|
) |
950 |
|
|
{ |
951 |
|
|
const AMBSAMP *d1 = (const AMBSAMP *)p1; |
952 |
|
|
const AMBSAMP *d2 = (const AMBSAMP *)p2; |
953 |
|
|
|
954 |
|
|
if (d1->k < d2->k) |
955 |
|
|
return(1); |
956 |
|
|
if (d1->k > d2->k) |
957 |
|
|
return(-1); |
958 |
|
|
return(0); |
959 |
|
|
} |
960 |
|
|
|
961 |
|
|
|
962 |
|
|
static int |
963 |
|
|
ambnorm( /* standard order */ |
964 |
|
|
const void *p1, |
965 |
|
|
const void *p2 |
966 |
|
|
) |
967 |
|
|
{ |
968 |
|
|
const AMBSAMP *d1 = (const AMBSAMP *)p1; |
969 |
|
|
const AMBSAMP *d2 = (const AMBSAMP *)p2; |
970 |
greg |
2.23 |
int c; |
971 |
greg |
2.14 |
|
972 |
|
|
if ( (c = d1->t - d2->t) ) |
973 |
|
|
return(c); |
974 |
|
|
return(d1->p - d2->p); |
975 |
|
|
} |
976 |
|
|
|
977 |
|
|
|
978 |
greg |
1.1 |
double |
979 |
greg |
2.14 |
doambient( /* compute ambient component */ |
980 |
greg |
2.23 |
COLOR rcol, |
981 |
greg |
2.14 |
RAY *r, |
982 |
|
|
double wt, |
983 |
|
|
FVECT pg, |
984 |
|
|
FVECT dg |
985 |
|
|
) |
986 |
greg |
1.1 |
{ |
987 |
greg |
2.24 |
double b, d=0; |
988 |
greg |
1.1 |
AMBHEMI hemi; |
989 |
|
|
AMBSAMP *div; |
990 |
|
|
AMBSAMP dnew; |
991 |
greg |
2.23 |
double acol[3]; |
992 |
|
|
AMBSAMP *dp; |
993 |
greg |
1.1 |
double arad; |
994 |
greg |
2.19 |
int divcnt; |
995 |
greg |
2.23 |
int i, j; |
996 |
greg |
1.1 |
/* initialize hemisphere */ |
997 |
greg |
2.23 |
inithemi(&hemi, rcol, r, wt); |
998 |
greg |
2.19 |
divcnt = hemi.nt * hemi.np; |
999 |
greg |
2.17 |
/* initialize */ |
1000 |
|
|
if (pg != NULL) |
1001 |
|
|
pg[0] = pg[1] = pg[2] = 0.0; |
1002 |
|
|
if (dg != NULL) |
1003 |
|
|
dg[0] = dg[1] = dg[2] = 0.0; |
1004 |
greg |
2.23 |
setcolor(rcol, 0.0, 0.0, 0.0); |
1005 |
greg |
2.19 |
if (divcnt == 0) |
1006 |
greg |
1.1 |
return(0.0); |
1007 |
greg |
2.14 |
/* allocate super-samples */ |
1008 |
greg |
2.15 |
if (hemi.ns > 0 || pg != NULL || dg != NULL) { |
1009 |
greg |
2.19 |
div = (AMBSAMP *)malloc(divcnt*sizeof(AMBSAMP)); |
1010 |
greg |
1.1 |
if (div == NULL) |
1011 |
|
|
error(SYSTEM, "out of memory in doambient"); |
1012 |
|
|
} else |
1013 |
|
|
div = NULL; |
1014 |
|
|
/* sample the divisions */ |
1015 |
|
|
arad = 0.0; |
1016 |
greg |
2.23 |
acol[0] = acol[1] = acol[2] = 0.0; |
1017 |
greg |
1.1 |
if ((dp = div) == NULL) |
1018 |
|
|
dp = &dnew; |
1019 |
greg |
2.19 |
divcnt = 0; |
1020 |
greg |
1.1 |
for (i = 0; i < hemi.nt; i++) |
1021 |
|
|
for (j = 0; j < hemi.np; j++) { |
1022 |
|
|
dp->t = i; dp->p = j; |
1023 |
|
|
setcolor(dp->v, 0.0, 0.0, 0.0); |
1024 |
greg |
1.2 |
dp->r = 0.0; |
1025 |
greg |
1.1 |
dp->n = 0; |
1026 |
greg |
2.16 |
if (divsample(dp, &hemi, r) < 0) { |
1027 |
greg |
2.19 |
if (div != NULL) |
1028 |
|
|
dp++; |
1029 |
greg |
2.16 |
continue; |
1030 |
|
|
} |
1031 |
greg |
2.6 |
arad += dp->r; |
1032 |
greg |
2.19 |
divcnt++; |
1033 |
greg |
1.1 |
if (div != NULL) |
1034 |
|
|
dp++; |
1035 |
greg |
2.6 |
else |
1036 |
greg |
1.1 |
addcolor(acol, dp->v); |
1037 |
|
|
} |
1038 |
greg |
2.21 |
if (!divcnt) { |
1039 |
|
|
if (div != NULL) |
1040 |
|
|
free((void *)div); |
1041 |
greg |
2.19 |
return(0.0); /* no samples taken */ |
1042 |
greg |
2.21 |
} |
1043 |
greg |
2.19 |
if (divcnt < hemi.nt*hemi.np) { |
1044 |
|
|
pg = dg = NULL; /* incomplete sampling */ |
1045 |
|
|
hemi.ns = 0; |
1046 |
|
|
} else if (arad > FTINY && divcnt/arad < minarad) { |
1047 |
greg |
2.15 |
hemi.ns = 0; /* close enough */ |
1048 |
greg |
2.19 |
} else if (hemi.ns > 0) { /* else perform super-sampling? */ |
1049 |
greg |
1.4 |
comperrs(div, &hemi); /* compute errors */ |
1050 |
greg |
2.19 |
qsort(div, divcnt, sizeof(AMBSAMP), ambcmp); /* sort divs */ |
1051 |
greg |
1.1 |
/* super-sample */ |
1052 |
greg |
2.15 |
for (i = hemi.ns; i > 0; i--) { |
1053 |
schorsch |
2.11 |
dnew = *div; |
1054 |
greg |
2.16 |
if (divsample(&dnew, &hemi, r) < 0) { |
1055 |
|
|
dp++; |
1056 |
|
|
continue; |
1057 |
|
|
} |
1058 |
|
|
dp = div; /* reinsert */ |
1059 |
greg |
2.19 |
j = divcnt < i ? divcnt : i; |
1060 |
greg |
1.1 |
while (--j > 0 && dnew.k < dp[1].k) { |
1061 |
schorsch |
2.11 |
*dp = *(dp+1); |
1062 |
greg |
1.1 |
dp++; |
1063 |
|
|
} |
1064 |
schorsch |
2.11 |
*dp = dnew; |
1065 |
greg |
1.1 |
} |
1066 |
greg |
1.2 |
if (pg != NULL || dg != NULL) /* restore order */ |
1067 |
greg |
2.19 |
qsort(div, divcnt, sizeof(AMBSAMP), ambnorm); |
1068 |
greg |
1.1 |
} |
1069 |
|
|
/* compute returned values */ |
1070 |
greg |
1.3 |
if (div != NULL) { |
1071 |
greg |
2.19 |
arad = 0.0; /* note: divcnt may be < nt*np */ |
1072 |
|
|
for (i = hemi.nt*hemi.np, dp = div; i-- > 0; dp++) { |
1073 |
greg |
1.3 |
arad += dp->r; |
1074 |
|
|
if (dp->n > 1) { |
1075 |
|
|
b = 1.0/dp->n; |
1076 |
|
|
scalecolor(dp->v, b); |
1077 |
|
|
dp->r *= b; |
1078 |
|
|
dp->n = 1; |
1079 |
|
|
} |
1080 |
|
|
addcolor(acol, dp->v); |
1081 |
|
|
} |
1082 |
greg |
1.5 |
b = bright(acol); |
1083 |
greg |
1.6 |
if (b > FTINY) { |
1084 |
greg |
2.17 |
b = 1.0/b; /* compute & normalize gradient(s) */ |
1085 |
greg |
1.6 |
if (pg != NULL) { |
1086 |
|
|
posgradient(pg, div, &hemi); |
1087 |
|
|
for (i = 0; i < 3; i++) |
1088 |
|
|
pg[i] *= b; |
1089 |
|
|
} |
1090 |
|
|
if (dg != NULL) { |
1091 |
|
|
dirgradient(dg, div, &hemi); |
1092 |
|
|
for (i = 0; i < 3; i++) |
1093 |
|
|
dg[i] *= b; |
1094 |
|
|
} |
1095 |
greg |
1.5 |
} |
1096 |
greg |
2.9 |
free((void *)div); |
1097 |
greg |
1.3 |
} |
1098 |
greg |
2.23 |
copycolor(rcol, acol); |
1099 |
greg |
1.1 |
if (arad <= FTINY) |
1100 |
greg |
1.16 |
arad = maxarad; |
1101 |
greg |
2.3 |
else |
1102 |
greg |
2.19 |
arad = (divcnt+hemi.ns)/arad; |
1103 |
greg |
1.15 |
if (pg != NULL) { /* reduce radius if gradient large */ |
1104 |
|
|
d = DOT(pg,pg); |
1105 |
|
|
if (d*arad*arad > 1.0) |
1106 |
|
|
arad = 1.0/sqrt(d); |
1107 |
|
|
} |
1108 |
greg |
1.16 |
if (arad < minarad) { |
1109 |
greg |
1.1 |
arad = minarad; |
1110 |
greg |
1.16 |
if (pg != NULL && d*arad*arad > 1.0) { /* cap gradient */ |
1111 |
|
|
d = 1.0/arad/sqrt(d); |
1112 |
|
|
for (i = 0; i < 3; i++) |
1113 |
|
|
pg[i] *= d; |
1114 |
|
|
} |
1115 |
|
|
} |
1116 |
greg |
2.3 |
if ((arad /= sqrt(wt)) > maxarad) |
1117 |
|
|
arad = maxarad; |
1118 |
|
|
return(arad); |
1119 |
greg |
1.1 |
} |
1120 |
|
|
|
1121 |
|
|
|
1122 |
greg |
2.9 |
void |
1123 |
greg |
2.14 |
comperrs( /* compute initial error estimates */ |
1124 |
|
|
AMBSAMP *da, /* assumes standard ordering */ |
1125 |
greg |
2.23 |
AMBHEMI *hp |
1126 |
greg |
2.14 |
) |
1127 |
greg |
1.1 |
{ |
1128 |
|
|
double b, b2; |
1129 |
|
|
int i, j; |
1130 |
greg |
2.23 |
AMBSAMP *dp; |
1131 |
greg |
1.1 |
/* sum differences from neighbors */ |
1132 |
|
|
dp = da; |
1133 |
|
|
for (i = 0; i < hp->nt; i++) |
1134 |
|
|
for (j = 0; j < hp->np; j++) { |
1135 |
greg |
1.6 |
#ifdef DEBUG |
1136 |
|
|
if (dp->t != i || dp->p != j) |
1137 |
|
|
error(CONSISTENCY, |
1138 |
|
|
"division order in comperrs"); |
1139 |
|
|
#endif |
1140 |
greg |
1.1 |
b = bright(dp[0].v); |
1141 |
|
|
if (i > 0) { /* from above */ |
1142 |
|
|
b2 = bright(dp[-hp->np].v) - b; |
1143 |
|
|
b2 *= b2 * 0.25; |
1144 |
|
|
dp[0].k += b2; |
1145 |
|
|
dp[-hp->np].k += b2; |
1146 |
|
|
} |
1147 |
|
|
if (j > 0) { /* from behind */ |
1148 |
|
|
b2 = bright(dp[-1].v) - b; |
1149 |
|
|
b2 *= b2 * 0.25; |
1150 |
|
|
dp[0].k += b2; |
1151 |
|
|
dp[-1].k += b2; |
1152 |
greg |
1.4 |
} else { /* around */ |
1153 |
|
|
b2 = bright(dp[hp->np-1].v) - b; |
1154 |
greg |
1.1 |
b2 *= b2 * 0.25; |
1155 |
|
|
dp[0].k += b2; |
1156 |
greg |
1.4 |
dp[hp->np-1].k += b2; |
1157 |
greg |
1.1 |
} |
1158 |
|
|
dp++; |
1159 |
|
|
} |
1160 |
|
|
/* divide by number of neighbors */ |
1161 |
|
|
dp = da; |
1162 |
|
|
for (j = 0; j < hp->np; j++) /* top row */ |
1163 |
|
|
(dp++)->k *= 1.0/3.0; |
1164 |
|
|
if (hp->nt < 2) |
1165 |
|
|
return; |
1166 |
|
|
for (i = 1; i < hp->nt-1; i++) /* central region */ |
1167 |
|
|
for (j = 0; j < hp->np; j++) |
1168 |
|
|
(dp++)->k *= 0.25; |
1169 |
|
|
for (j = 0; j < hp->np; j++) /* bottom row */ |
1170 |
|
|
(dp++)->k *= 1.0/3.0; |
1171 |
|
|
} |
1172 |
|
|
|
1173 |
|
|
|
1174 |
greg |
2.9 |
void |
1175 |
greg |
2.14 |
posgradient( /* compute position gradient */ |
1176 |
|
|
FVECT gv, |
1177 |
|
|
AMBSAMP *da, /* assumes standard ordering */ |
1178 |
greg |
2.23 |
AMBHEMI *hp |
1179 |
greg |
2.14 |
) |
1180 |
greg |
1.1 |
{ |
1181 |
greg |
2.23 |
int i, j; |
1182 |
greg |
2.2 |
double nextsine, lastsine, b, d; |
1183 |
greg |
1.2 |
double mag0, mag1; |
1184 |
|
|
double phi, cosp, sinp, xd, yd; |
1185 |
greg |
2.23 |
AMBSAMP *dp; |
1186 |
greg |
1.2 |
|
1187 |
|
|
xd = yd = 0.0; |
1188 |
|
|
for (j = 0; j < hp->np; j++) { |
1189 |
|
|
dp = da + j; |
1190 |
|
|
mag0 = mag1 = 0.0; |
1191 |
greg |
2.2 |
lastsine = 0.0; |
1192 |
greg |
1.2 |
for (i = 0; i < hp->nt; i++) { |
1193 |
|
|
#ifdef DEBUG |
1194 |
|
|
if (dp->t != i || dp->p != j) |
1195 |
|
|
error(CONSISTENCY, |
1196 |
|
|
"division order in posgradient"); |
1197 |
|
|
#endif |
1198 |
|
|
b = bright(dp->v); |
1199 |
|
|
if (i > 0) { |
1200 |
|
|
d = dp[-hp->np].r; |
1201 |
|
|
if (dp[0].r > d) d = dp[0].r; |
1202 |
greg |
2.2 |
/* sin(t)*cos(t)^2 */ |
1203 |
|
|
d *= lastsine * (1.0 - (double)i/hp->nt); |
1204 |
greg |
1.2 |
mag0 += d*(b - bright(dp[-hp->np].v)); |
1205 |
|
|
} |
1206 |
greg |
2.2 |
nextsine = sqrt((double)(i+1)/hp->nt); |
1207 |
greg |
1.2 |
if (j > 0) { |
1208 |
|
|
d = dp[-1].r; |
1209 |
|
|
if (dp[0].r > d) d = dp[0].r; |
1210 |
greg |
2.2 |
mag1 += d * (nextsine - lastsine) * |
1211 |
|
|
(b - bright(dp[-1].v)); |
1212 |
greg |
1.2 |
} else { |
1213 |
|
|
d = dp[hp->np-1].r; |
1214 |
|
|
if (dp[0].r > d) d = dp[0].r; |
1215 |
greg |
2.2 |
mag1 += d * (nextsine - lastsine) * |
1216 |
|
|
(b - bright(dp[hp->np-1].v)); |
1217 |
greg |
1.2 |
} |
1218 |
|
|
dp += hp->np; |
1219 |
greg |
2.2 |
lastsine = nextsine; |
1220 |
greg |
1.2 |
} |
1221 |
greg |
2.2 |
mag0 *= 2.0*PI / hp->np; |
1222 |
greg |
1.2 |
phi = 2.0*PI * (double)j/hp->np; |
1223 |
gwlarson |
2.8 |
cosp = tcos(phi); sinp = tsin(phi); |
1224 |
greg |
1.2 |
xd += mag0*cosp - mag1*sinp; |
1225 |
|
|
yd += mag0*sinp + mag1*cosp; |
1226 |
|
|
} |
1227 |
|
|
for (i = 0; i < 3; i++) |
1228 |
greg |
2.16 |
gv[i] = (xd*hp->ux[i] + yd*hp->uy[i])*(hp->nt*hp->np)/PI; |
1229 |
greg |
1.1 |
} |
1230 |
|
|
|
1231 |
|
|
|
1232 |
greg |
2.9 |
void |
1233 |
greg |
2.14 |
dirgradient( /* compute direction gradient */ |
1234 |
|
|
FVECT gv, |
1235 |
|
|
AMBSAMP *da, /* assumes standard ordering */ |
1236 |
greg |
2.23 |
AMBHEMI *hp |
1237 |
greg |
2.14 |
) |
1238 |
greg |
1.1 |
{ |
1239 |
greg |
2.23 |
int i, j; |
1240 |
greg |
1.2 |
double mag; |
1241 |
|
|
double phi, xd, yd; |
1242 |
greg |
2.23 |
AMBSAMP *dp; |
1243 |
greg |
1.2 |
|
1244 |
|
|
xd = yd = 0.0; |
1245 |
|
|
for (j = 0; j < hp->np; j++) { |
1246 |
|
|
dp = da + j; |
1247 |
|
|
mag = 0.0; |
1248 |
|
|
for (i = 0; i < hp->nt; i++) { |
1249 |
|
|
#ifdef DEBUG |
1250 |
|
|
if (dp->t != i || dp->p != j) |
1251 |
|
|
error(CONSISTENCY, |
1252 |
|
|
"division order in dirgradient"); |
1253 |
|
|
#endif |
1254 |
greg |
2.2 |
/* tan(t) */ |
1255 |
|
|
mag += bright(dp->v)/sqrt(hp->nt/(i+.5) - 1.0); |
1256 |
greg |
1.2 |
dp += hp->np; |
1257 |
|
|
} |
1258 |
|
|
phi = 2.0*PI * (j+.5)/hp->np + PI/2.0; |
1259 |
gwlarson |
2.8 |
xd += mag * tcos(phi); |
1260 |
|
|
yd += mag * tsin(phi); |
1261 |
greg |
1.2 |
} |
1262 |
|
|
for (i = 0; i < 3; i++) |
1263 |
greg |
2.16 |
gv[i] = xd*hp->ux[i] + yd*hp->uy[i]; |
1264 |
greg |
1.1 |
} |
1265 |
greg |
2.25 |
|
1266 |
|
|
#endif /* ! NEWAMB */ |