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#ifndef lint |
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static const char RCSid[] = "$Id: ambcomp.c,v 2.25 2014/04/11 20:31:37 greg Exp $"; |
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#endif |
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/* |
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* Routines to compute "ambient" values using Monte Carlo |
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* |
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* Declarations of external symbols in ambient.h |
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*/ |
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|
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#include "copyright.h" |
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|
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#include "ray.h" |
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#include "ambient.h" |
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#include "random.h" |
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|
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#ifdef NEWAMB |
17 |
|
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extern void SDsquare2disk(double ds[2], double seedx, double seedy); |
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|
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typedef struct { |
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RAY *rp; /* originating ray sample */ |
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FVECT ux, uy; /* tangent axis directions */ |
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int ns; /* number of samples per axis */ |
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COLOR acoef; /* division contribution coefficient */ |
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struct s_ambsamp { |
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COLOR v; /* hemisphere sample value */ |
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float p[3]; /* intersection point */ |
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} sa[1]; /* sample array (extends struct) */ |
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} AMBHEMI; /* ambient sample hemisphere */ |
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|
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#define ambsamp(h,i,j) (h)->sa[(i)*(h)->ns + (j)] |
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|
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|
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static AMBHEMI * |
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inithemi( /* initialize sampling hemisphere */ |
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COLOR ac, |
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RAY *r, |
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double wt |
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) |
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{ |
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AMBHEMI *hp; |
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double d; |
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int n, i; |
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/* set number of divisions */ |
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if (ambacc <= FTINY && |
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wt > (d = 0.8*intens(ac)*r->rweight/(ambdiv*minweight))) |
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wt = d; /* avoid ray termination */ |
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n = sqrt(ambdiv * wt) + 0.5; |
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i = 1 + 4*(ambacc > FTINY); /* minimum number of samples */ |
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if (n < i) |
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n = i; |
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/* allocate sampling array */ |
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hp = (AMBHEMI *)malloc(sizeof(AMBHEMI) + |
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sizeof(struct s_ambsamp)*(n*n - 1)); |
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if (hp == NULL) |
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return(NULL); |
57 |
hp->rp = r; |
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hp->ns = n; |
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/* assign coefficient */ |
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copycolor(hp->acoef, ac); |
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d = 1.0/(n*n); |
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scalecolor(hp->acoef, d); |
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/* make tangent axes */ |
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hp->uy[0] = hp->uy[1] = hp->uy[2] = 0.0; |
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for (i = 0; i < 3; i++) |
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if (r->rn[i] < 0.6 && r->rn[i] > -0.6) |
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break; |
68 |
if (i >= 3) |
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error(CONSISTENCY, "bad ray direction in inithemi()"); |
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hp->uy[i] = 1.0; |
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VCROSS(hp->ux, hp->uy, r->rn); |
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normalize(hp->ux); |
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VCROSS(hp->uy, r->rn, hp->ux); |
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/* we're ready to sample */ |
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return(hp); |
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} |
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|
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|
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static int |
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ambsample( /* sample an ambient direction */ |
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AMBHEMI *hp, |
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int i, |
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int j, |
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) |
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{ |
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struct s_ambsamp *ap = &ambsamp(hp,i,j); |
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RAY ar; |
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int hlist[3]; |
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double spt[2], dz; |
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int ii; |
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/* ambient coefficient for weight */ |
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if (ambacc > FTINY) |
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setcolor(ar.rcoef, AVGREFL, AVGREFL, AVGREFL); |
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else |
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copycolor(ar.rcoef, hp->acoef); |
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if (rayorigin(&ar, AMBIENT, hp->rp, ar.rcoef) < 0) { |
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setcolor(ap->v, 0., 0., 0.); |
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ap->r = 0.; |
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return(0); /* no sample taken */ |
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} |
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if (ambacc > FTINY) { |
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multcolor(ar.rcoef, hp->acoef); |
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scalecolor(ar.rcoef, 1./AVGREFL); |
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} |
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/* generate hemispherical sample */ |
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SDsquare2disk(spt, (i+frandom())/hp->ns, (j+frandom())/hp->ns); |
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zd = sqrt(1. - spt[0]*spt[0] - spt[1]*spt[1]); |
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for (ii = 3; ii--; ) |
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ar.rdir[ii] = spt[0]*hp->ux[ii] + |
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spt[1]*hp->uy[ii] + |
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zd*hp->rp->ron[ii]; |
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checknorm(ar.rdir); |
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dimlist[ndims++] = i*hp->ns + j + 90171; |
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rayvalue(&ar); /* evaluate ray */ |
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ndims--; |
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multcolor(ar.rcol, ar.rcoef); /* apply coefficient */ |
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copycolor(ap->v, ar.rcol); |
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if (ar.rt > 20.0*maxarad) /* limit vertex distance */ |
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ar.rt = 20.0*maxarad; |
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VSUM(ap->p, ar.rorg, ar.rdir, ar.rt); |
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return(1); |
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} |
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|
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|
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static void |
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ambHessian( /* anisotropic radii & pos. gradient */ |
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AMBHEMI *hp, |
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FVECT uv[2], /* returned */ |
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float ra[2], /* returned */ |
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float pg[2] /* returned */ |
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) |
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{ |
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if (ra != NULL) { /* compute Hessian-derived radii */ |
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} else { /* else copy original tangent axes */ |
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VCOPY(uv[0], hp->ux); |
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VCOPY(uv[1], hp->uy); |
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} |
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if (pg == NULL) /* no position gradient requested? */ |
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return; |
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} |
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|
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int |
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doambient( /* compute ambient component */ |
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COLOR rcol, /* input/output color */ |
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RAY *r, |
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double wt, |
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FVECT uv[2], /* returned */ |
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float ra[2], /* returned */ |
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float pg[2], /* returned */ |
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float dg[2] /* returned */ |
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) |
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{ |
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int cnt = 0; |
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FVECT my_uv[2]; |
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AMBHEMI *hp; |
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double d, acol[3]; |
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struct s_ambsamp *ap; |
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int i, j; |
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/* initialize */ |
160 |
if ((hp = inithemi(rcol, r, wt)) == NULL) |
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return(0); |
162 |
if (uv != NULL) |
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memset(uv, 0, sizeof(FVECT)*2); |
164 |
if (ra != NULL) |
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ra[0] = ra[1] = 0.0; |
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if (pg != NULL) |
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pg[0] = pg[1] = 0.0; |
168 |
if (dg != NULL) |
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dg[0] = dg[1] = 0.0; |
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/* sample the hemisphere */ |
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acol[0] = acol[1] = acol[2] = 0.0; |
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for (i = hemi.ns; i--; ) |
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for (j = hemi.ns; j--; ) |
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if (ambsample(hp, i, j)) { |
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ap = &ambsamp(hp,i,j); |
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addcolor(acol, ap->v); |
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++cnt; |
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} |
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if (!cnt) { |
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setcolor(rcol, 0.0, 0.0, 0.0); |
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free(hp); |
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return(0); /* no valid samples */ |
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} |
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d = 1.0 / cnt; /* final indirect irradiance/PI */ |
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acol[0] *= d; acol[1] *= d; acol[2] *= d; |
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copycolor(rcol, acol); |
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if (cnt < hp->ns*hp->ns || /* incomplete sampling? */ |
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(ra == NULL) & (pg == NULL) & (dg == NULL)) { |
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free(hp); |
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return(-1); /* no radius or gradient calc. */ |
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} |
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d = 0.01 * bright(rcol); /* add in 1% before Hessian comp. */ |
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if (d < FTINY) d = FTINY; |
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ap = hp->sa; /* using Y channel from here on... */ |
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for (i = hp->ns*hp->ns; i--; ap++) |
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colval(ap->v,CIEY) = bright(ap->v) + d; |
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|
198 |
if (uv == NULL) /* make sure we have axis pointers */ |
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uv = my_uv; |
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/* compute radii & pos. gradient */ |
201 |
ambHessian(hp, uv, ra, pg); |
202 |
if (dg != NULL) /* compute direction gradient */ |
203 |
ambdirgrad(hp, uv, dg); |
204 |
if (ra != NULL) { /* adjust/clamp radii */ |
205 |
d = pow(wt, -0.25); |
206 |
if ((ra[0] *= d) > maxarad) |
207 |
ra[0] = maxarad; |
208 |
if ((ra[1] *= d) > 2.0*ra[0]) |
209 |
ra[1] = 2.0*ra[0]; |
210 |
} |
211 |
free(hp); /* clean up and return */ |
212 |
return(1); |
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} |
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|
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|
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#else /* ! NEWAMB */ |
217 |
|
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|
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void |
220 |
inithemi( /* initialize sampling hemisphere */ |
221 |
AMBHEMI *hp, |
222 |
COLOR ac, |
223 |
RAY *r, |
224 |
double wt |
225 |
) |
226 |
{ |
227 |
double d; |
228 |
int i; |
229 |
/* set number of divisions */ |
230 |
if (ambacc <= FTINY && |
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wt > (d = 0.8*intens(ac)*r->rweight/(ambdiv*minweight))) |
232 |
wt = d; /* avoid ray termination */ |
233 |
hp->nt = sqrt(ambdiv * wt / PI) + 0.5; |
234 |
i = ambacc > FTINY ? 3 : 1; /* minimum number of samples */ |
235 |
if (hp->nt < i) |
236 |
hp->nt = i; |
237 |
hp->np = PI * hp->nt + 0.5; |
238 |
/* set number of super-samples */ |
239 |
hp->ns = ambssamp * wt + 0.5; |
240 |
/* assign coefficient */ |
241 |
copycolor(hp->acoef, ac); |
242 |
d = 1.0/(hp->nt*hp->np); |
243 |
scalecolor(hp->acoef, d); |
244 |
/* make axes */ |
245 |
VCOPY(hp->uz, r->ron); |
246 |
hp->uy[0] = hp->uy[1] = hp->uy[2] = 0.0; |
247 |
for (i = 0; i < 3; i++) |
248 |
if (hp->uz[i] < 0.6 && hp->uz[i] > -0.6) |
249 |
break; |
250 |
if (i >= 3) |
251 |
error(CONSISTENCY, "bad ray direction in inithemi"); |
252 |
hp->uy[i] = 1.0; |
253 |
fcross(hp->ux, hp->uy, hp->uz); |
254 |
normalize(hp->ux); |
255 |
fcross(hp->uy, hp->uz, hp->ux); |
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} |
257 |
|
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|
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int |
260 |
divsample( /* sample a division */ |
261 |
AMBSAMP *dp, |
262 |
AMBHEMI *h, |
263 |
RAY *r |
264 |
) |
265 |
{ |
266 |
RAY ar; |
267 |
int hlist[3]; |
268 |
double spt[2]; |
269 |
double xd, yd, zd; |
270 |
double b2; |
271 |
double phi; |
272 |
int i; |
273 |
/* ambient coefficient for weight */ |
274 |
if (ambacc > FTINY) |
275 |
setcolor(ar.rcoef, AVGREFL, AVGREFL, AVGREFL); |
276 |
else |
277 |
copycolor(ar.rcoef, h->acoef); |
278 |
if (rayorigin(&ar, AMBIENT, r, ar.rcoef) < 0) |
279 |
return(-1); |
280 |
if (ambacc > FTINY) { |
281 |
multcolor(ar.rcoef, h->acoef); |
282 |
scalecolor(ar.rcoef, 1./AVGREFL); |
283 |
} |
284 |
hlist[0] = r->rno; |
285 |
hlist[1] = dp->t; |
286 |
hlist[2] = dp->p; |
287 |
multisamp(spt, 2, urand(ilhash(hlist,3)+dp->n)); |
288 |
zd = sqrt((dp->t + spt[0])/h->nt); |
289 |
phi = 2.0*PI * (dp->p + spt[1])/h->np; |
290 |
xd = tcos(phi) * zd; |
291 |
yd = tsin(phi) * zd; |
292 |
zd = sqrt(1.0 - zd*zd); |
293 |
for (i = 0; i < 3; i++) |
294 |
ar.rdir[i] = xd*h->ux[i] + |
295 |
yd*h->uy[i] + |
296 |
zd*h->uz[i]; |
297 |
checknorm(ar.rdir); |
298 |
dimlist[ndims++] = dp->t*h->np + dp->p + 90171; |
299 |
rayvalue(&ar); |
300 |
ndims--; |
301 |
multcolor(ar.rcol, ar.rcoef); /* apply coefficient */ |
302 |
addcolor(dp->v, ar.rcol); |
303 |
/* use rt to improve gradient calc */ |
304 |
if (ar.rt > FTINY && ar.rt < FHUGE) |
305 |
dp->r += 1.0/ar.rt; |
306 |
/* (re)initialize error */ |
307 |
if (dp->n++) { |
308 |
b2 = bright(dp->v)/dp->n - bright(ar.rcol); |
309 |
b2 = b2*b2 + dp->k*((dp->n-1)*(dp->n-1)); |
310 |
dp->k = b2/(dp->n*dp->n); |
311 |
} else |
312 |
dp->k = 0.0; |
313 |
return(0); |
314 |
} |
315 |
|
316 |
|
317 |
static int |
318 |
ambcmp( /* decreasing order */ |
319 |
const void *p1, |
320 |
const void *p2 |
321 |
) |
322 |
{ |
323 |
const AMBSAMP *d1 = (const AMBSAMP *)p1; |
324 |
const AMBSAMP *d2 = (const AMBSAMP *)p2; |
325 |
|
326 |
if (d1->k < d2->k) |
327 |
return(1); |
328 |
if (d1->k > d2->k) |
329 |
return(-1); |
330 |
return(0); |
331 |
} |
332 |
|
333 |
|
334 |
static int |
335 |
ambnorm( /* standard order */ |
336 |
const void *p1, |
337 |
const void *p2 |
338 |
) |
339 |
{ |
340 |
const AMBSAMP *d1 = (const AMBSAMP *)p1; |
341 |
const AMBSAMP *d2 = (const AMBSAMP *)p2; |
342 |
int c; |
343 |
|
344 |
if ( (c = d1->t - d2->t) ) |
345 |
return(c); |
346 |
return(d1->p - d2->p); |
347 |
} |
348 |
|
349 |
|
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double |
351 |
doambient( /* compute ambient component */ |
352 |
COLOR rcol, |
353 |
RAY *r, |
354 |
double wt, |
355 |
FVECT pg, |
356 |
FVECT dg |
357 |
) |
358 |
{ |
359 |
double b, d=0; |
360 |
AMBHEMI hemi; |
361 |
AMBSAMP *div; |
362 |
AMBSAMP dnew; |
363 |
double acol[3]; |
364 |
AMBSAMP *dp; |
365 |
double arad; |
366 |
int divcnt; |
367 |
int i, j; |
368 |
/* initialize hemisphere */ |
369 |
inithemi(&hemi, rcol, r, wt); |
370 |
divcnt = hemi.nt * hemi.np; |
371 |
/* initialize */ |
372 |
if (pg != NULL) |
373 |
pg[0] = pg[1] = pg[2] = 0.0; |
374 |
if (dg != NULL) |
375 |
dg[0] = dg[1] = dg[2] = 0.0; |
376 |
setcolor(rcol, 0.0, 0.0, 0.0); |
377 |
if (divcnt == 0) |
378 |
return(0.0); |
379 |
/* allocate super-samples */ |
380 |
if (hemi.ns > 0 || pg != NULL || dg != NULL) { |
381 |
div = (AMBSAMP *)malloc(divcnt*sizeof(AMBSAMP)); |
382 |
if (div == NULL) |
383 |
error(SYSTEM, "out of memory in doambient"); |
384 |
} else |
385 |
div = NULL; |
386 |
/* sample the divisions */ |
387 |
arad = 0.0; |
388 |
acol[0] = acol[1] = acol[2] = 0.0; |
389 |
if ((dp = div) == NULL) |
390 |
dp = &dnew; |
391 |
divcnt = 0; |
392 |
for (i = 0; i < hemi.nt; i++) |
393 |
for (j = 0; j < hemi.np; j++) { |
394 |
dp->t = i; dp->p = j; |
395 |
setcolor(dp->v, 0.0, 0.0, 0.0); |
396 |
dp->r = 0.0; |
397 |
dp->n = 0; |
398 |
if (divsample(dp, &hemi, r) < 0) { |
399 |
if (div != NULL) |
400 |
dp++; |
401 |
continue; |
402 |
} |
403 |
arad += dp->r; |
404 |
divcnt++; |
405 |
if (div != NULL) |
406 |
dp++; |
407 |
else |
408 |
addcolor(acol, dp->v); |
409 |
} |
410 |
if (!divcnt) { |
411 |
if (div != NULL) |
412 |
free((void *)div); |
413 |
return(0.0); /* no samples taken */ |
414 |
} |
415 |
if (divcnt < hemi.nt*hemi.np) { |
416 |
pg = dg = NULL; /* incomplete sampling */ |
417 |
hemi.ns = 0; |
418 |
} else if (arad > FTINY && divcnt/arad < minarad) { |
419 |
hemi.ns = 0; /* close enough */ |
420 |
} else if (hemi.ns > 0) { /* else perform super-sampling? */ |
421 |
comperrs(div, &hemi); /* compute errors */ |
422 |
qsort(div, divcnt, sizeof(AMBSAMP), ambcmp); /* sort divs */ |
423 |
/* super-sample */ |
424 |
for (i = hemi.ns; i > 0; i--) { |
425 |
dnew = *div; |
426 |
if (divsample(&dnew, &hemi, r) < 0) { |
427 |
dp++; |
428 |
continue; |
429 |
} |
430 |
dp = div; /* reinsert */ |
431 |
j = divcnt < i ? divcnt : i; |
432 |
while (--j > 0 && dnew.k < dp[1].k) { |
433 |
*dp = *(dp+1); |
434 |
dp++; |
435 |
} |
436 |
*dp = dnew; |
437 |
} |
438 |
if (pg != NULL || dg != NULL) /* restore order */ |
439 |
qsort(div, divcnt, sizeof(AMBSAMP), ambnorm); |
440 |
} |
441 |
/* compute returned values */ |
442 |
if (div != NULL) { |
443 |
arad = 0.0; /* note: divcnt may be < nt*np */ |
444 |
for (i = hemi.nt*hemi.np, dp = div; i-- > 0; dp++) { |
445 |
arad += dp->r; |
446 |
if (dp->n > 1) { |
447 |
b = 1.0/dp->n; |
448 |
scalecolor(dp->v, b); |
449 |
dp->r *= b; |
450 |
dp->n = 1; |
451 |
} |
452 |
addcolor(acol, dp->v); |
453 |
} |
454 |
b = bright(acol); |
455 |
if (b > FTINY) { |
456 |
b = 1.0/b; /* compute & normalize gradient(s) */ |
457 |
if (pg != NULL) { |
458 |
posgradient(pg, div, &hemi); |
459 |
for (i = 0; i < 3; i++) |
460 |
pg[i] *= b; |
461 |
} |
462 |
if (dg != NULL) { |
463 |
dirgradient(dg, div, &hemi); |
464 |
for (i = 0; i < 3; i++) |
465 |
dg[i] *= b; |
466 |
} |
467 |
} |
468 |
free((void *)div); |
469 |
} |
470 |
copycolor(rcol, acol); |
471 |
if (arad <= FTINY) |
472 |
arad = maxarad; |
473 |
else |
474 |
arad = (divcnt+hemi.ns)/arad; |
475 |
if (pg != NULL) { /* reduce radius if gradient large */ |
476 |
d = DOT(pg,pg); |
477 |
if (d*arad*arad > 1.0) |
478 |
arad = 1.0/sqrt(d); |
479 |
} |
480 |
if (arad < minarad) { |
481 |
arad = minarad; |
482 |
if (pg != NULL && d*arad*arad > 1.0) { /* cap gradient */ |
483 |
d = 1.0/arad/sqrt(d); |
484 |
for (i = 0; i < 3; i++) |
485 |
pg[i] *= d; |
486 |
} |
487 |
} |
488 |
if ((arad /= sqrt(wt)) > maxarad) |
489 |
arad = maxarad; |
490 |
return(arad); |
491 |
} |
492 |
|
493 |
|
494 |
void |
495 |
comperrs( /* compute initial error estimates */ |
496 |
AMBSAMP *da, /* assumes standard ordering */ |
497 |
AMBHEMI *hp |
498 |
) |
499 |
{ |
500 |
double b, b2; |
501 |
int i, j; |
502 |
AMBSAMP *dp; |
503 |
/* sum differences from neighbors */ |
504 |
dp = da; |
505 |
for (i = 0; i < hp->nt; i++) |
506 |
for (j = 0; j < hp->np; j++) { |
507 |
#ifdef DEBUG |
508 |
if (dp->t != i || dp->p != j) |
509 |
error(CONSISTENCY, |
510 |
"division order in comperrs"); |
511 |
#endif |
512 |
b = bright(dp[0].v); |
513 |
if (i > 0) { /* from above */ |
514 |
b2 = bright(dp[-hp->np].v) - b; |
515 |
b2 *= b2 * 0.25; |
516 |
dp[0].k += b2; |
517 |
dp[-hp->np].k += b2; |
518 |
} |
519 |
if (j > 0) { /* from behind */ |
520 |
b2 = bright(dp[-1].v) - b; |
521 |
b2 *= b2 * 0.25; |
522 |
dp[0].k += b2; |
523 |
dp[-1].k += b2; |
524 |
} else { /* around */ |
525 |
b2 = bright(dp[hp->np-1].v) - b; |
526 |
b2 *= b2 * 0.25; |
527 |
dp[0].k += b2; |
528 |
dp[hp->np-1].k += b2; |
529 |
} |
530 |
dp++; |
531 |
} |
532 |
/* divide by number of neighbors */ |
533 |
dp = da; |
534 |
for (j = 0; j < hp->np; j++) /* top row */ |
535 |
(dp++)->k *= 1.0/3.0; |
536 |
if (hp->nt < 2) |
537 |
return; |
538 |
for (i = 1; i < hp->nt-1; i++) /* central region */ |
539 |
for (j = 0; j < hp->np; j++) |
540 |
(dp++)->k *= 0.25; |
541 |
for (j = 0; j < hp->np; j++) /* bottom row */ |
542 |
(dp++)->k *= 1.0/3.0; |
543 |
} |
544 |
|
545 |
|
546 |
void |
547 |
posgradient( /* compute position gradient */ |
548 |
FVECT gv, |
549 |
AMBSAMP *da, /* assumes standard ordering */ |
550 |
AMBHEMI *hp |
551 |
) |
552 |
{ |
553 |
int i, j; |
554 |
double nextsine, lastsine, b, d; |
555 |
double mag0, mag1; |
556 |
double phi, cosp, sinp, xd, yd; |
557 |
AMBSAMP *dp; |
558 |
|
559 |
xd = yd = 0.0; |
560 |
for (j = 0; j < hp->np; j++) { |
561 |
dp = da + j; |
562 |
mag0 = mag1 = 0.0; |
563 |
lastsine = 0.0; |
564 |
for (i = 0; i < hp->nt; i++) { |
565 |
#ifdef DEBUG |
566 |
if (dp->t != i || dp->p != j) |
567 |
error(CONSISTENCY, |
568 |
"division order in posgradient"); |
569 |
#endif |
570 |
b = bright(dp->v); |
571 |
if (i > 0) { |
572 |
d = dp[-hp->np].r; |
573 |
if (dp[0].r > d) d = dp[0].r; |
574 |
/* sin(t)*cos(t)^2 */ |
575 |
d *= lastsine * (1.0 - (double)i/hp->nt); |
576 |
mag0 += d*(b - bright(dp[-hp->np].v)); |
577 |
} |
578 |
nextsine = sqrt((double)(i+1)/hp->nt); |
579 |
if (j > 0) { |
580 |
d = dp[-1].r; |
581 |
if (dp[0].r > d) d = dp[0].r; |
582 |
mag1 += d * (nextsine - lastsine) * |
583 |
(b - bright(dp[-1].v)); |
584 |
} else { |
585 |
d = dp[hp->np-1].r; |
586 |
if (dp[0].r > d) d = dp[0].r; |
587 |
mag1 += d * (nextsine - lastsine) * |
588 |
(b - bright(dp[hp->np-1].v)); |
589 |
} |
590 |
dp += hp->np; |
591 |
lastsine = nextsine; |
592 |
} |
593 |
mag0 *= 2.0*PI / hp->np; |
594 |
phi = 2.0*PI * (double)j/hp->np; |
595 |
cosp = tcos(phi); sinp = tsin(phi); |
596 |
xd += mag0*cosp - mag1*sinp; |
597 |
yd += mag0*sinp + mag1*cosp; |
598 |
} |
599 |
for (i = 0; i < 3; i++) |
600 |
gv[i] = (xd*hp->ux[i] + yd*hp->uy[i])*(hp->nt*hp->np)/PI; |
601 |
} |
602 |
|
603 |
|
604 |
void |
605 |
dirgradient( /* compute direction gradient */ |
606 |
FVECT gv, |
607 |
AMBSAMP *da, /* assumes standard ordering */ |
608 |
AMBHEMI *hp |
609 |
) |
610 |
{ |
611 |
int i, j; |
612 |
double mag; |
613 |
double phi, xd, yd; |
614 |
AMBSAMP *dp; |
615 |
|
616 |
xd = yd = 0.0; |
617 |
for (j = 0; j < hp->np; j++) { |
618 |
dp = da + j; |
619 |
mag = 0.0; |
620 |
for (i = 0; i < hp->nt; i++) { |
621 |
#ifdef DEBUG |
622 |
if (dp->t != i || dp->p != j) |
623 |
error(CONSISTENCY, |
624 |
"division order in dirgradient"); |
625 |
#endif |
626 |
/* tan(t) */ |
627 |
mag += bright(dp->v)/sqrt(hp->nt/(i+.5) - 1.0); |
628 |
dp += hp->np; |
629 |
} |
630 |
phi = 2.0*PI * (j+.5)/hp->np + PI/2.0; |
631 |
xd += mag * tcos(phi); |
632 |
yd += mag * tsin(phi); |
633 |
} |
634 |
for (i = 0; i < 3; i++) |
635 |
gv[i] = xd*hp->ux[i] + yd*hp->uy[i]; |
636 |
} |
637 |
|
638 |
#endif /* ! NEWAMB */ |