[ViewVC] Diff of: radiance/ray/src/rt/ambcomp.c

Comparing ray/src/rt/ambcomp.c (file contents):
Revision 2.70 by greg, Thu May 21 05:54:54 2015 UTC vs.
Revision 2.93 by greg, Tue Apr 16 23:32:20 2024 UTC

#	Line 21 \| Line 21 \| static const char RCSid[] = "$Id$";
21		#include "ambient.h"
22		#include "random.h"
23
24	<	#ifndef OLDAMB
24	>	#ifndef MINADIV
25	>	#define MINADIV 7 /* minimum # divisions in each dimension */
26	>	#endif
27
26	–	extern void SDsquare2disk(double ds[2], double seedx, double seedy);
27	–
28		typedef struct {
29	–	COLOR v; /* hemisphere sample value */
30	–	float d; /* reciprocal distance (1/rt) */
29		FVECT p; /* intersection point */
30	+	float d; /* reciprocal distance */
31	+	SCOLOR v; /* hemisphere sample value */
32		} AMBSAMP; /* sample value */
33
34		typedef struct {
35		RAY rp; / originating ray sample */
36		int ns; /* number of samples per axis */
37		int sampOK; /* acquired full sample set? */
38	<	COLOR acoef; /* division contribution coefficient */
39	<	double acol[3]; /* accumulated color */
38	>	int atyp; /* RAMBIENT or TAMBIENT */
39	>	SCOLOR acoef; /* division contribution coefficient */
40	>	SCOLOR acol; /* accumulated color */
41	>	FVECT onrm; /* oriented unperturbed surface normal */
42		FVECT ux, uy; /* tangent axis unit vectors */
43		AMBSAMP sa[1]; /* sample array (extends struct) */
44		} AMBHEMI; /* ambient sample hemisphere */
#	Line 51 \| Line 53 \| typedef struct {
53
54
55		static int
56	+	ambcollision( /* proposed direciton collides? */
57	+	AMBHEMI *hp,
58	+	int i,
59	+	int j,
60	+	FVECT dv
61	+	)
62	+	{
63	+	double cos_thresh;
64	+	int ii, jj;
65	+	/* min. spacing = 1/4th division */
66	+	cos_thresh = (PI/4.)/(double)hp->ns;
67	+	cos_thresh = 1. - .5cos_threshcos_thresh;
68	+	/* check existing neighbors */
69	+	for (ii = i-1; ii <= i+1; ii++) {
70	+	if (ii < 0) continue;
71	+	if (ii >= hp->ns) break;
72	+	for (jj = j-1; jj <= j+1; jj++) {
73	+	AMBSAMP *ap;
74	+	FVECT avec;
75	+	double dprod;
76	+	if (jj < 0) continue;
77	+	if (jj >= hp->ns) break;
78	+	if ((ii==i) & (jj==j)) continue;
79	+	ap = &ambsam(hp,ii,jj);
80	+	if (ap->d <= .5/FHUGE)
81	+	continue; /* no one home */
82	+	VSUB(avec, ap->p, hp->rp->rop);
83	+	dprod = DOT(avec, dv);
84	+	if (dprod >= cos_thresh*VLEN(avec))
85	+	return(1); /* collision */
86	+	}
87	+	}
88	+	return(0); /* nothing to worry about */
89	+	}
90	+
91	+
92	+	static int
93		ambsample( /* initial ambient division sample */
94		AMBHEMI *hp,
95		int i,
#	Line 61 \| Line 100 \| *ambsample( / initial ambient division sample /*
100		AMBSAMP *ap = &ambsam(hp,i,j);
101		RAY ar;
102		int hlist[3], ii;
103	<	double spt[2], zd;
103	>	RREAL spt[2];
104	>	double zd;
105		/* generate hemispherical sample */
106		/* ambient coefficient for weight */
107		if (ambacc > FTINY)
108	<	setcolor(ar.rcoef, AVGREFL, AVGREFL, AVGREFL);
108	>	setscolor(ar.rcoef, AVGREFL, AVGREFL, AVGREFL);
109		else
110	<	copycolor(ar.rcoef, hp->acoef);
111	<	if (rayorigin(&ar, AMBIENT, hp->rp, ar.rcoef) < 0)
110	>	copyscolor(ar.rcoef, hp->acoef);
111	>	if (rayorigin(&ar, hp->atyp, hp->rp, ar.rcoef) < 0)
112		return(0);
113		if (ambacc > FTINY) {
114	<	multcolor(ar.rcoef, hp->acoef);
115	<	scalecolor(ar.rcoef, 1./AVGREFL);
114	>	smultscolor(ar.rcoef, hp->acoef);
115	>	scalescolor(ar.rcoef, 1./AVGREFL);
116		}
117		hlist[0] = hp->rp->rno;
118		hlist[1] = j;
119		hlist[2] = i;
120		multisamp(spt, 2, urand(ilhash(hlist,3)+n));
121	<	/* avoid coincident samples */
122	<	if (!n && (0 < i) & (i < hp->ns-1) &&
83	<	(0 < j) & (j < hp->ns-1)) {
84	<	if ((spt[0] < 0.1) \| (spt[0] >= 0.9))
85	<	spt[0] = 0.1 + 0.8*frandom();
86	<	if ((spt[1] < 0.1) \| (spt[1] >= 0.9))
87	<	spt[1] = 0.1 + 0.8*frandom();
88	<	}
89	<	SDsquare2disk(spt, (j+spt[1])/hp->ns, (i+spt[0])/hp->ns);
121	>	resample:
122	>	square2disk(spt, (j+spt[1])/hp->ns, (i+spt[0])/hp->ns);
123		zd = sqrt(1. - spt[0]spt[0] - spt[1]spt[1]);
124		for (ii = 3; ii--; )
125		ar.rdir[ii] = spt[0]*hp->ux[ii] +
126		spt[1]*hp->uy[ii] +
127	<	zd*hp->rp->ron[ii];
127	>	zd*hp->onrm[ii];
128		checknorm(ar.rdir);
129	+	/* avoid coincident samples */
130	+	if (!n && ambcollision(hp, i, j, ar.rdir)) {
131	+	spt[0] = frandom(); spt[1] = frandom();
132	+	goto resample; /* reject this sample */
133	+	}
134		dimlist[ndims++] = AI(hp,i,j) + 90171;
135		rayvalue(&ar); /* evaluate ray */
136		ndims--;
137	<	if (ar.rt <= FTINY)
137	>	zd = raydistance(&ar);
138	>	if (zd <= FTINY)
139		return(0); /* should never happen */
140	<	multcolor(ar.rcol, ar.rcoef); /* apply coefficient */
141	<	if (ar.rtap->d < 1.0) / new/closer distance? */
142	<	ap->d = 1.0/ar.rt;
140	>	smultscolor(ar.rcol, ar.rcoef); /* apply coefficient */
141	>	if (zdap->d < 1.0) / new/closer distance? */
142	>	ap->d = 1.0/zd;
143		if (!n) { /* record first vertex & value */
144	<	if (ar.rt > 10.0*thescene.cusize)
145	<	ar.rt = 10.0*thescene.cusize;
146	<	VSUM(ap->p, ar.rorg, ar.rdir, ar.rt);
147	<	copycolor(ap->v, ar.rcol);
144	>	if (zd > 10.0*thescene.cusize + 1000.)
145	>	zd = 10.0*thescene.cusize + 1000.;
146	>	VSUM(ap->p, ar.rorg, ar.rdir, zd);
147	>	copyscolor(ap->v, ar.rcol);
148		} else { /* else update recorded value */
149	<	hp->acol[RED] -= colval(ap->v,RED);
111	<	hp->acol[GRN] -= colval(ap->v,GRN);
112	<	hp->acol[BLU] -= colval(ap->v,BLU);
149	>	sopscolor(hp->acol, -=, ap->v);
150		zd = 1.0/(double)(n+1);
151	<	scalecolor(ar.rcol, zd);
151	>	scalescolor(ar.rcol, zd);
152		zd *= (double)n;
153	<	scalecolor(ap->v, zd);
154	<	addcolor(ap->v, ar.rcol);
153	>	scalescolor(ap->v, zd);
154	>	saddscolor(ap->v, ar.rcol);
155		}
156	<	addcolor(hp->acol, ap->v); /* add to our sum */
156	>	saddscolor(hp->acol, ap->v); /* add to our sum */
157		return(1);
158		}
159
160
161	<	/* Estimate errors based on ambient division differences */
161	>	/* Estimate variance based on ambient division differences */
162		static float *
163		getambdiffs(AMBHEMI *hp)
164		{
165	+	const double normf = 1./(pbright(hp->acoef) + FTINY);
166		float earr = (float )calloc(hp->ns*hp->ns, sizeof(float));
167	<	float *ep;
167	>	float ep, earr2;
168		AMBSAMP *ap;
169	<	double b, d2;
169	>	double b, b1, d2;
170		int i, j;
171
172		if (earr == NULL) /* out of memory? */
173		return(NULL);
174	<	/* compute squared neighbor diffs */
174	>	/* sum squared neighbor diffs */
175		for (ap = hp->sa, ep = earr, i = 0; i < hp->ns; i++)
176		for (j = 0; j < hp->ns; j++, ap++, ep++) {
177	<	b = bright(ap[0].v);
177	>	b = pbright(ap[0].v);
178		if (i) { /* from above */
179	<	d2 = b - bright(ap[-hp->ns].v);
180	<	d2 *= d2;
179	>	b1 = pbright(ap[-hp->ns].v);
180	>	d2 = b - b1;
181	>	d2 = d2normf/(b + b1 + FTINY);
182		ep[0] += d2;
183		ep[-hp->ns] += d2;
184		}
185		if (!j) continue;
186		/* from behind */
187	<	d2 = b - bright(ap[-1].v);
188	<	d2 *= d2;
187	>	b1 = pbright(ap[-1].v);
188	>	d2 = b - b1;
189	>	d2 = d2normf/(b + b1 + FTINY);
190		ep[0] += d2;
191		ep[-1] += d2;
192		if (!i) continue;
193		/* diagonal */
194	<	d2 = b - bright(ap[-hp->ns-1].v);
195	<	d2 *= d2;
194	>	b1 = pbright(ap[-hp->ns-1].v);
195	>	d2 = b - b1;
196	>	d2 = d2normf/(b + b1 + FTINY);
197		ep[0] += d2;
198		ep[-hp->ns-1] += d2;
199		}
200		/* correct for number of neighbors */
201	<	earr[0] *= 8./3.;
202	<	earr[hp->ns-1] *= 8./3.;
203	<	earr[(hp->ns-1)hp->ns] = 8./3.;
204	<	earr[(hp->ns-1)hp->ns + hp->ns-1] = 8./3.;
201	>	earr[0] *= 6./3.;
202	>	earr[hp->ns-1] *= 6./3.;
203	>	earr[(hp->ns-1)hp->ns] = 6./3.;
204	>	earr[(hp->ns-1)hp->ns + hp->ns-1] = 6./3.;
205		for (i = 1; i < hp->ns-1; i++) {
206	<	earr[ihp->ns] = 8./5.;
207	<	earr[ihp->ns + hp->ns-1] = 8./5.;
206	>	earr[ihp->ns] = 6./5.;
207	>	earr[ihp->ns + hp->ns-1] = 6./5.;
208		}
209		for (j = 1; j < hp->ns-1; j++) {
210	<	earr[j] *= 8./5.;
211	<	earr[(hp->ns-1)hp->ns + j] = 8./5.;
210	>	earr[j] *= 6./5.;
211	>	earr[(hp->ns-1)hp->ns + j] = 6./5.;
212		}
213	+	/* preen map to avoid cliffs */
214	+	earr2 = (float )malloc(hp->nshp->ns*sizeof(float));
215	+	if (earr2 == NULL)
216	+	return(earr);
217	+	memcpy(earr2, earr, hp->nshp->nssizeof(float));
218	+	for (i = 0; i < hp->ns-1; i++) {
219	+	float ep2 = earr2 + ihp->ns;
220	+	ep = earr + i*hp->ns;
221	+	for (j = 0; j < hp->ns-1; j++, ep2++, ep++) {
222	+	if (ep2[1] < .5*ep2[0]) {
223	+	ep[0] -= .125*ep2[0];
224	+	ep[1] += .125*ep2[0];
225	+	} else if (ep2[1] > 2.*ep2[0]) {
226	+	ep[1] -= .125*ep2[1];
227	+	ep[0] += .125*ep2[1];
228	+	}
229	+	if (ep2[hp->ns] < .5*ep2[0]) {
230	+	ep[0] -= .125*ep2[0];
231	+	ep[hp->ns] += .125*ep2[0];
232	+	} else if (ep2[hp->ns] > 2.*ep2[0]) {
233	+	ep[hp->ns] -= .125*ep2[hp->ns];
234	+	ep[0] += .125*ep2[hp->ns];
235	+	}
236	+	}
237	+	}
238	+	free(earr2);
239		return(earr);
240		}
241
#	Line 179 \| Line 246 \| *ambsupersamp(AMBHEMI hp, int cnt)**
246		{
247		float *earr = getambdiffs(hp);
248		double e2rem = 0;
182	–	AMBSAMP *ap;
249		float *ep;
250		int i, j, n, nss;
251
#	Line 189 \| Line 255 \| *ambsupersamp(AMBHEMI hp, int cnt)**
255		for (ep = earr + hp->ns*hp->ns; ep > earr; )
256		e2rem += *--ep;
257		ep = earr; /* perform super-sampling */
258	<	for (ap = hp->sa, i = 0; i < hp->ns; i++)
259	<	for (j = 0; j < hp->ns; j++, ap++) {
258	>	for (i = 0; i < hp->ns; i++)
259	>	for (j = 0; j < hp->ns; j++) {
260		if (e2rem <= FTINY)
261		goto done; /* nothing left to do */
262		nss = ep/e2remcnt + frandom();
263		for (n = 1; n <= nss && ambsample(hp,i,j,n); n++)
264	<	--cnt;
264	>	if (!--cnt) goto done;
265		e2rem -= ep++; / update remainder */
266		}
267		done:
#	Line 205 \| Line 271 \| done:
271
272		static AMBHEMI *
273		samp_hemi( /* sample indirect hemisphere */
274	<	COLOR rcol,
274	>	SCOLOR rcol,
275		RAY *r,
276		double wt
277		)
278		{
279	+	int backside = (wt < 0);
280		AMBHEMI *hp;
281		double d;
282		int n, i, j;
283	+	/* insignificance check */
284	+	d = sintens(rcol);
285	+	if (d <= FTINY)
286	+	return(NULL);
287		/* set number of divisions */
288	+	if (backside) wt = -wt;
289		if (ambacc <= FTINY &&
290	<	wt > (d = 0.8intens(rcol)r->rweight/(ambdiv*minweight)))
290	>	wt > (d = 0.8r->rweight/(ambdiv*minweight)))
291		wt = d; /* avoid ray termination */
292		n = sqrt(ambdiv * wt) + 0.5;
293	<	i = 1 + 5(ambacc > FTINY); / minimum number of samples */
294	<	if (n < i)
293	>	i = 1 + (MINADIV-1)*(ambacc > FTINY);
294	>	if (n < i) /* use minimum number of samples? */
295		n = i;
296		/* allocate sampling array */
297		hp = (AMBHEMI )malloc(sizeof(AMBHEMI) + sizeof(AMBSAMP)(n*n - 1));
298		if (hp == NULL)
299		error(SYSTEM, "out of memory in samp_hemi");
300	+
301	+	if (backside) {
302	+	hp->atyp = TAMBIENT;
303	+	hp->onrm[0] = -r->ron[0];
304	+	hp->onrm[1] = -r->ron[1];
305	+	hp->onrm[2] = -r->ron[2];
306	+	} else {
307	+	hp->atyp = RAMBIENT;
308	+	VCOPY(hp->onrm, r->ron);
309	+	}
310		hp->rp = r;
311		hp->ns = n;
312	<	hp->acol[RED] = hp->acol[GRN] = hp->acol[BLU] = 0.0;
312	>	scolorblack(hp->acol);
313		memset(hp->sa, 0, sizeof(AMBSAMP)nn);
314		hp->sampOK = 0;
315		/* assign coefficient */
316	<	copycolor(hp->acoef, rcol);
316	>	copyscolor(hp->acoef, rcol);
317		d = 1.0/(n*n);
318	<	scalecolor(hp->acoef, d);
318	>	scalescolor(hp->acoef, d);
319		/* make tangent plane axes */
320	<	if (!getperpendicular(hp->ux, r->ron, 1))
320	>	if (!getperpendicular(hp->ux, hp->onrm, 1))
321		error(CONSISTENCY, "bad ray direction in samp_hemi");
322	<	VCROSS(hp->uy, r->ron, hp->ux);
322	>	VCROSS(hp->uy, hp->onrm, hp->ux);
323		/* sample divisions */
324		for (i = hp->ns; i--; )
325		for (j = hp->ns; j--; )
326		hp->sampOK += ambsample(hp, i, j, 0);
327	<	copycolor(rcol, hp->acol);
327	>	copyscolor(rcol, hp->acol);
328		if (!hp->sampOK) { /* utter failure? */
329		free(hp);
330		return(NULL);
#	Line 251 \| Line 333 \| *samp_hemi( / sample indirect hemisphere /*
333		hp->sampOK = -1; / soft failure */
334		return(hp);
335		}
336	+	if (hp->sampOK <= MINADIV*MINADIV)
337	+	return(hp); /* don't bother super-sampling */
338		n = ambssamp*wt + 0.5;
339		if (n > 8) { /* perform super-sampling? */
340		ambsupersamp(hp, n);
341	<	copycolor(rcol, hp->acol);
341	>	copyscolor(rcol, hp->acol);
342		}
343		return(hp); /* all is well */
344		}
#	Line 266 \| Line 350 \| *back_ambval(AMBHEMI hp, const int n1, const int n2, c**
350		{
351		if (hp->sa[n1].d <= hp->sa[n2].d) {
352		if (hp->sa[n1].d <= hp->sa[n3].d)
353	<	return(colval(hp->sa[n1].v,CIEY));
354	<	return(colval(hp->sa[n3].v,CIEY));
353	>	return(hp->sa[n1].v[0]);
354	>	return(hp->sa[n3].v[0]);
355		}
356		if (hp->sa[n2].d <= hp->sa[n3].d)
357	<	return(colval(hp->sa[n2].v,CIEY));
358	<	return(colval(hp->sa[n3].v,CIEY));
357	>	return(hp->sa[n2].v[0]);
358	>	return(hp->sa[n3].v[0]);
359		}
360
361
#	Line 500 \| Line 584 \| *ambHessian( / anisotropic radii & pos. gradient /*
584		for (j = 0; j < hp->ns-1; j++) {
585		comp_fftri(&fftr, hp, AI(hp,0,j), AI(hp,0,j+1));
586		if (hessrow != NULL)
587	<	comp_hessian(hessrow[j], &fftr, hp->rp->ron);
587	>	comp_hessian(hessrow[j], &fftr, hp->onrm);
588		if (gradrow != NULL)
589	<	comp_gradient(gradrow[j], &fftr, hp->rp->ron);
589	>	comp_gradient(gradrow[j], &fftr, hp->onrm);
590		}
591		/* sum each row of triangles */
592		for (i = 0; i < hp->ns-1; i++) {
#	Line 510 \| Line 594 \| *ambHessian( / anisotropic radii & pos. gradient /*
594		FVECT gradcol;
595		comp_fftri(&fftr, hp, AI(hp,i,0), AI(hp,i+1,0));
596		if (hessrow != NULL)
597	<	comp_hessian(hesscol, &fftr, hp->rp->ron);
597	>	comp_hessian(hesscol, &fftr, hp->onrm);
598		if (gradrow != NULL)
599	<	comp_gradient(gradcol, &fftr, hp->rp->ron);
599	>	comp_gradient(gradcol, &fftr, hp->onrm);
600		for (j = 0; j < hp->ns-1; j++) {
601		FVECT hessdia[3]; /* compute triangle contributions */
602		FVECT graddia;
#	Line 522 \| Line 606 \| *ambHessian( / anisotropic radii & pos. gradient /*
606		/* diagonal (inner) edge */
607		comp_fftri(&fftr, hp, AI(hp,i,j+1), AI(hp,i+1,j));
608		if (hessrow != NULL) {
609	<	comp_hessian(hessdia, &fftr, hp->rp->ron);
609	>	comp_hessian(hessdia, &fftr, hp->onrm);
610		rev_hessian(hesscol);
611		add2hessian(hessian, hessrow[j], hessdia, hesscol, backg);
612		}
613		if (gradrow != NULL) {
614	<	comp_gradient(graddia, &fftr, hp->rp->ron);
614	>	comp_gradient(graddia, &fftr, hp->onrm);
615		rev_gradient(gradcol);
616		add2gradient(gradient, gradrow[j], graddia, gradcol, backg);
617		}
618		/* initialize edge in next row */
619		comp_fftri(&fftr, hp, AI(hp,i+1,j+1), AI(hp,i+1,j));
620		if (hessrow != NULL)
621	<	comp_hessian(hessrow[j], &fftr, hp->rp->ron);
621	>	comp_hessian(hessrow[j], &fftr, hp->onrm);
622		if (gradrow != NULL)
623	<	comp_gradient(gradrow[j], &fftr, hp->rp->ron);
623	>	comp_gradient(gradrow[j], &fftr, hp->onrm);
624		/* new column edge & paired triangle */
625		backg = back_ambval(hp, AI(hp,i+1,j+1),
626		AI(hp,i+1,j), AI(hp,i,j+1));
627		comp_fftri(&fftr, hp, AI(hp,i,j+1), AI(hp,i+1,j+1));
628		if (hessrow != NULL) {
629	<	comp_hessian(hesscol, &fftr, hp->rp->ron);
629	>	comp_hessian(hesscol, &fftr, hp->onrm);
630		rev_hessian(hessdia);
631		add2hessian(hessian, hessrow[j], hessdia, hesscol, backg);
632		if (i < hp->ns-2)
633		rev_hessian(hessrow[j]);
634		}
635		if (gradrow != NULL) {
636	<	comp_gradient(gradcol, &fftr, hp->rp->ron);
636	>	comp_gradient(gradcol, &fftr, hp->onrm);
637		rev_gradient(graddia);
638		add2gradient(gradient, gradrow[j], graddia, gradcol, backg);
639		if (i < hp->ns-2)
#	Line 585 \| Line 669 \| *ambdirgrad(AMBHEMI hp, FVECT uv[2], float dg[2])**
669		/* use vector for azimuth + 90deg */
670		VSUB(vd, ap->p, hp->rp->rop);
671		/* brightness over cosine factor */
672	<	gfact = colval(ap->v,CIEY) / DOT(hp->rp->ron, vd);
672	>	gfact = ap->v[0] / DOT(hp->onrm, vd);
673		/* sine = proj_radius/vd_length */
674		dgsum[0] -= DOT(uv[1], vd) * gfact;
675		dgsum[1] += DOT(uv[0], vd) * gfact;
#	Line 609 \| Line 693 \| *ambcorral(AMBHEMI hp, FVECT uv[2], const double r0, c**
693		double ang, a1;
694		int i, j;
695		/* don't bother for a few samples */
696	<	if (hp->ns < 12)
696	>	if (hp->ns < 8)
697		return(0);
698		/* check distances overhead */
699		for (i = hp->ns*3/4; i-- > hp->ns>>2; )
#	Line 635 \| Line 719 \| *ambcorral(AMBHEMI hp, FVECT uv[2], const double r0, c**
719		for (a1 = ang-ang_res; a1 <= ang+ang_res; a1 += ang_step)
720		flgs \|= 1L<<(int)(16/PI(a1 + 2.PI*(a1 < 0)));
721		}
638	–	/* add low-angle incident (< 20deg) */
639	–	if (fabs(hp->rp->rod) <= 0.342) {
640	–	u = -DOT(hp->rp->rdir, uv[0]);
641	–	v = -DOT(hp->rp->rdir, uv[1]);
642	–	if ((r0r0uu + r1r1vv) > hp->rp->rot*hp->rp->rot) {
643	–	ang = atan2a(v, u);
644	–	ang += 2.PI(ang < 0);
645	–	ang *= 16/PI;
646	–	if ((ang < .5) \| (ang >= 31.5))
647	–	flgs \|= 0x80000001;
648	–	else
649	–	flgs \|= 3L<<(int)(ang-.5);
650	–	}
651	–	}
722		return(flgs);
723		}
724
725
726		int
727		doambient( /* compute ambient component */
728	<	COLOR rcol, /* input/output color */
728	>	SCOLOR rcol, /* input/output color */
729		RAY *r,
730	<	double wt,
730	>	double wt, /* negative for back side */
731		FVECT uv[2], /* returned (optional) */
732		float ra[2], /* returned (optional) */
733		float pg[2], /* returned (optional) */
#	Line 685 \| Line 755 \| *doambient( / compute ambient component /*
755		return(0);
756
757		if ((ra == NULL) & (pg == NULL) & (dg == NULL) \|\|
758	<	(hp->sampOK < 0) \| (hp->ns < 6)) {
758	>	(hp->sampOK < 0) \| (hp->ns < MINADIV)) {
759		free(hp); /* Hessian not requested/possible */
760		return(-1); /* value-only return value */
761		}
762	<	if ((d = bright(rcol)) > FTINY) { /* normalize Y values */
763	<	d = 0.99(hp->nshp->ns)/d;
762	>	if ((d = scolor_mean(rcol)) > FTINY) {
763	>	d = 0.99(hp->nshp->ns)/d; /* normalize avg. values */
764		K = 0.01;
765		} else { /* or fall back on geometric Hessian */
766		K = 1.0;
#	Line 698 \| Line 768 \| *doambient( / compute ambient component /*
768		dg = NULL;
769		crlp = NULL;
770		}
771	<	ap = hp->sa; /* relative Y channel from here on... */
771	>	ap = hp->sa; /* single channel from here on... */
772		for (i = hp->ns*hp->ns; i--; ap++)
773	<	colval(ap->v,CIEY) = bright(ap->v)*d + K;
773	>	ap->v[0] = scolor_mean(ap->v)*d + K;
774
775		if (uv == NULL) /* make sure we have axis pointers */
776		uv = my_uv;
#	Line 724 \| Line 794 \| *doambient( / compute ambient component /*
794		if (ra[1] < minarad)
795		ra[1] = minarad;
796		}
797	<	ra[0] *= d = 1.0/sqrt(wt);
797	>	ra[0] *= d = 1.0/sqrt(fabs(wt));
798		if ((ra[1] = d) > 2.0ra[0])
799		ra[1] = 2.0*ra[0];
800		if (ra[1] > maxarad) {
#	Line 733 \| Line 803 \| *doambient( / compute ambient component /*
803		ra[0] = maxarad;
804		}
805		/* flag encroached directions */
806	<	if ((wt >= 0.89*AVGREFL) & (crlp != NULL))
806	>	if (crlp != NULL) /* XXX doesn't update with changes to ambacc */
807		crlp = ambcorral(hp, uv, ra[0]ambacc, ra[1]*ambacc);
808		if (pg != NULL) { /* cap gradient if necessary */
809		d = pg[0]pg[0]ra[0]ra[0] + pg[1]pg[1]ra[1]ra[1];
#	Line 747 \| Line 817 \| *doambient( / compute ambient component /*
817		free(hp); /* clean up and return */
818		return(1);
819		}
750	–
751	–
752	–	#else /* ! NEWAMB */
753	–
754	–
755	–	void
756	–	inithemi( /* initialize sampling hemisphere */
757	–	AMBHEMI *hp,
758	–	COLOR ac,
759	–	RAY *r,
760	–	double wt
761	–	)
762	–	{
763	–	double d;
764	–	int i;
765	–	/* set number of divisions */
766	–	if (ambacc <= FTINY &&
767	–	wt > (d = 0.8intens(ac)r->rweight/(ambdiv*minweight)))
768	–	wt = d; /* avoid ray termination */
769	–	hp->nt = sqrt(ambdiv * wt / PI) + 0.5;
770	–	i = ambacc > FTINY ? 3 : 1; /* minimum number of samples */
771	–	if (hp->nt < i)
772	–	hp->nt = i;
773	–	hp->np = PI * hp->nt + 0.5;
774	–	/* set number of super-samples */
775	–	hp->ns = ambssamp * wt + 0.5;
776	–	/* assign coefficient */
777	–	copycolor(hp->acoef, ac);
778	–	d = 1.0/(hp->nt*hp->np);
779	–	scalecolor(hp->acoef, d);
780	–	/* make axes */
781	–	VCOPY(hp->uz, r->ron);
782	–	hp->uy[0] = hp->uy[1] = hp->uy[2] = 0.0;
783	–	for (i = 0; i < 3; i++)
784	–	if (hp->uz[i] < 0.6 && hp->uz[i] > -0.6)
785	–	break;
786	–	if (i >= 3)
787	–	error(CONSISTENCY, "bad ray direction in inithemi");
788	–	hp->uy[i] = 1.0;
789	–	fcross(hp->ux, hp->uy, hp->uz);
790	–	normalize(hp->ux);
791	–	fcross(hp->uy, hp->uz, hp->ux);
792	–	}
793	–
794	–
795	–	int
796	–	divsample( /* sample a division */
797	–	AMBSAMP *dp,
798	–	AMBHEMI *h,
799	–	RAY *r
800	–	)
801	–	{
802	–	RAY ar;
803	–	int hlist[3];
804	–	double spt[2];
805	–	double xd, yd, zd;
806	–	double b2;
807	–	double phi;
808	–	int i;
809	–	/* ambient coefficient for weight */
810	–	if (ambacc > FTINY)
811	–	setcolor(ar.rcoef, AVGREFL, AVGREFL, AVGREFL);
812	–	else
813	–	copycolor(ar.rcoef, h->acoef);
814	–	if (rayorigin(&ar, AMBIENT, r, ar.rcoef) < 0)
815	–	return(-1);
816	–	if (ambacc > FTINY) {
817	–	multcolor(ar.rcoef, h->acoef);
818	–	scalecolor(ar.rcoef, 1./AVGREFL);
819	–	}
820	–	hlist[0] = r->rno;
821	–	hlist[1] = dp->t;
822	–	hlist[2] = dp->p;
823	–	multisamp(spt, 2, urand(ilhash(hlist,3)+dp->n));
824	–	zd = sqrt((dp->t + spt[0])/h->nt);
825	–	phi = 2.0PI (dp->p + spt[1])/h->np;
826	–	xd = tcos(phi) * zd;
827	–	yd = tsin(phi) * zd;
828	–	zd = sqrt(1.0 - zd*zd);
829	–	for (i = 0; i < 3; i++)
830	–	ar.rdir[i] = xd*h->ux[i] +
831	–	yd*h->uy[i] +
832	–	zd*h->uz[i];
833	–	checknorm(ar.rdir);
834	–	dimlist[ndims++] = dp->t*h->np + dp->p + 90171;
835	–	rayvalue(&ar);
836	–	ndims--;
837	–	multcolor(ar.rcol, ar.rcoef); /* apply coefficient */
838	–	addcolor(dp->v, ar.rcol);
839	–	/* use rt to improve gradient calc */
840	–	if (ar.rt > FTINY && ar.rt < FHUGE)
841	–	dp->r += 1.0/ar.rt;
842	–	/* (re)initialize error */
843	–	if (dp->n++) {
844	–	b2 = bright(dp->v)/dp->n - bright(ar.rcol);
845	–	b2 = b2b2 + dp->k((dp->n-1)*(dp->n-1));
846	–	dp->k = b2/(dp->n*dp->n);
847	–	} else
848	–	dp->k = 0.0;
849	–	return(0);
850	–	}
851	–
852	–
853	–	static int
854	–	ambcmp( /* decreasing order */
855	–	const void *p1,
856	–	const void *p2
857	–	)
858	–	{
859	–	const AMBSAMP d1 = (const AMBSAMP )p1;
860	–	const AMBSAMP d2 = (const AMBSAMP )p2;
861	–
862	–	if (d1->k < d2->k)
863	–	return(1);
864	–	if (d1->k > d2->k)
865	–	return(-1);
866	–	return(0);
867	–	}
868	–
869	–
870	–	static int
871	–	ambnorm( /* standard order */
872	–	const void *p1,
873	–	const void *p2
874	–	)
875	–	{
876	–	const AMBSAMP d1 = (const AMBSAMP )p1;
877	–	const AMBSAMP d2 = (const AMBSAMP )p2;
878	–	int c;
879	–
880	–	if ( (c = d1->t - d2->t) )
881	–	return(c);
882	–	return(d1->p - d2->p);
883	–	}
884	–
885	–
886	–	double
887	–	doambient( /* compute ambient component */
888	–	COLOR rcol,
889	–	RAY *r,
890	–	double wt,
891	–	FVECT pg,
892	–	FVECT dg
893	–	)
894	–	{
895	–	double b, d=0;
896	–	AMBHEMI hemi;
897	–	AMBSAMP *div;
898	–	AMBSAMP dnew;
899	–	double acol[3];
900	–	AMBSAMP *dp;
901	–	double arad;
902	–	int divcnt;
903	–	int i, j;
904	–	/* initialize hemisphere */
905	–	inithemi(&hemi, rcol, r, wt);
906	–	divcnt = hemi.nt * hemi.np;
907	–	/* initialize */
908	–	if (pg != NULL)
909	–	pg[0] = pg[1] = pg[2] = 0.0;
910	–	if (dg != NULL)
911	–	dg[0] = dg[1] = dg[2] = 0.0;
912	–	setcolor(rcol, 0.0, 0.0, 0.0);
913	–	if (divcnt == 0)
914	–	return(0.0);
915	–	/* allocate super-samples */
916	–	if (hemi.ns > 0 \|\| pg != NULL \|\| dg != NULL) {
917	–	div = (AMBSAMP )malloc(divcntsizeof(AMBSAMP));
918	–	if (div == NULL)
919	–	error(SYSTEM, "out of memory in doambient");
920	–	} else
921	–	div = NULL;
922	–	/* sample the divisions */
923	–	arad = 0.0;
924	–	acol[0] = acol[1] = acol[2] = 0.0;
925	–	if ((dp = div) == NULL)
926	–	dp = &dnew;
927	–	divcnt = 0;
928	–	for (i = 0; i < hemi.nt; i++)
929	–	for (j = 0; j < hemi.np; j++) {
930	–	dp->t = i; dp->p = j;
931	–	setcolor(dp->v, 0.0, 0.0, 0.0);
932	–	dp->r = 0.0;
933	–	dp->n = 0;
934	–	if (divsample(dp, &hemi, r) < 0) {
935	–	if (div != NULL)
936	–	dp++;
937	–	continue;
938	–	}
939	–	arad += dp->r;
940	–	divcnt++;
941	–	if (div != NULL)
942	–	dp++;
943	–	else
944	–	addcolor(acol, dp->v);
945	–	}
946	–	if (!divcnt) {
947	–	if (div != NULL)
948	–	free((void *)div);
949	–	return(0.0); /* no samples taken */
950	–	}
951	–	if (divcnt < hemi.nt*hemi.np) {
952	–	pg = dg = NULL; /* incomplete sampling */
953	–	hemi.ns = 0;
954	–	} else if (arad > FTINY && divcnt/arad < minarad) {
955	–	hemi.ns = 0; /* close enough */
956	–	} else if (hemi.ns > 0) { /* else perform super-sampling? */
957	–	comperrs(div, &hemi); /* compute errors */
958	–	qsort(div, divcnt, sizeof(AMBSAMP), ambcmp); /* sort divs */
959	–	/* super-sample */
960	–	for (i = hemi.ns; i > 0; i--) {
961	–	dnew = *div;
962	–	if (divsample(&dnew, &hemi, r) < 0) {
963	–	dp++;
964	–	continue;
965	–	}
966	–	dp = div; /* reinsert */
967	–	j = divcnt < i ? divcnt : i;
968	–	while (--j > 0 && dnew.k < dp[1].k) {
969	–	dp = (dp+1);
970	–	dp++;
971	–	}
972	–	*dp = dnew;
973	–	}
974	–	if (pg != NULL \|\| dg != NULL) /* restore order */
975	–	qsort(div, divcnt, sizeof(AMBSAMP), ambnorm);
976	–	}
977	–	/* compute returned values */
978	–	if (div != NULL) {
979	–	arad = 0.0; /* note: divcnt may be < ntnp /
980	–	for (i = hemi.nt*hemi.np, dp = div; i-- > 0; dp++) {
981	–	arad += dp->r;
982	–	if (dp->n > 1) {
983	–	b = 1.0/dp->n;
984	–	scalecolor(dp->v, b);
985	–	dp->r *= b;
986	–	dp->n = 1;
987	–	}
988	–	addcolor(acol, dp->v);
989	–	}
990	–	b = bright(acol);
991	–	if (b > FTINY) {
992	–	b = 1.0/b; /* compute & normalize gradient(s) */
993	–	if (pg != NULL) {
994	–	posgradient(pg, div, &hemi);
995	–	for (i = 0; i < 3; i++)
996	–	pg[i] *= b;
997	–	}
998	–	if (dg != NULL) {
999	–	dirgradient(dg, div, &hemi);
1000	–	for (i = 0; i < 3; i++)
1001	–	dg[i] *= b;
1002	–	}
1003	–	}
1004	–	free((void *)div);
1005	–	}
1006	–	copycolor(rcol, acol);
1007	–	if (arad <= FTINY)
1008	–	arad = maxarad;
1009	–	else
1010	–	arad = (divcnt+hemi.ns)/arad;
1011	–	if (pg != NULL) { /* reduce radius if gradient large */
1012	–	d = DOT(pg,pg);
1013	–	if (daradarad > 1.0)
1014	–	arad = 1.0/sqrt(d);
1015	–	}
1016	–	if (arad < minarad) {
1017	–	arad = minarad;
1018	–	if (pg != NULL && daradarad > 1.0) { /* cap gradient */
1019	–	d = 1.0/arad/sqrt(d);
1020	–	for (i = 0; i < 3; i++)
1021	–	pg[i] *= d;
1022	–	}
1023	–	}
1024	–	if ((arad /= sqrt(wt)) > maxarad)
1025	–	arad = maxarad;
1026	–	return(arad);
1027	–	}
1028	–
1029	–
1030	–	void
1031	–	comperrs( /* compute initial error estimates */
1032	–	AMBSAMP da, / assumes standard ordering */
1033	–	AMBHEMI *hp
1034	–	)
1035	–	{
1036	–	double b, b2;
1037	–	int i, j;
1038	–	AMBSAMP *dp;
1039	–	/* sum differences from neighbors */
1040	–	dp = da;
1041	–	for (i = 0; i < hp->nt; i++)
1042	–	for (j = 0; j < hp->np; j++) {
1043	–	#ifdef DEBUG
1044	–	if (dp->t != i \|\| dp->p != j)
1045	–	error(CONSISTENCY,
1046	–	"division order in comperrs");
1047	–	#endif
1048	–	b = bright(dp[0].v);
1049	–	if (i > 0) { /* from above */
1050	–	b2 = bright(dp[-hp->np].v) - b;
1051	–	b2 = b2 0.25;
1052	–	dp[0].k += b2;
1053	–	dp[-hp->np].k += b2;
1054	–	}
1055	–	if (j > 0) { /* from behind */
1056	–	b2 = bright(dp[-1].v) - b;
1057	–	b2 = b2 0.25;
1058	–	dp[0].k += b2;
1059	–	dp[-1].k += b2;
1060	–	} else { /* around */
1061	–	b2 = bright(dp[hp->np-1].v) - b;
1062	–	b2 = b2 0.25;
1063	–	dp[0].k += b2;
1064	–	dp[hp->np-1].k += b2;
1065	–	}
1066	–	dp++;
1067	–	}
1068	–	/* divide by number of neighbors */
1069	–	dp = da;
1070	–	for (j = 0; j < hp->np; j++) /* top row */
1071	–	(dp++)->k *= 1.0/3.0;
1072	–	if (hp->nt < 2)
1073	–	return;
1074	–	for (i = 1; i < hp->nt-1; i++) /* central region */
1075	–	for (j = 0; j < hp->np; j++)
1076	–	(dp++)->k *= 0.25;
1077	–	for (j = 0; j < hp->np; j++) /* bottom row */
1078	–	(dp++)->k *= 1.0/3.0;
1079	–	}
1080	–
1081	–
1082	–	void
1083	–	posgradient( /* compute position gradient */
1084	–	FVECT gv,
1085	–	AMBSAMP da, / assumes standard ordering */
1086	–	AMBHEMI *hp
1087	–	)
1088	–	{
1089	–	int i, j;
1090	–	double nextsine, lastsine, b, d;
1091	–	double mag0, mag1;
1092	–	double phi, cosp, sinp, xd, yd;
1093	–	AMBSAMP *dp;
1094	–
1095	–	xd = yd = 0.0;
1096	–	for (j = 0; j < hp->np; j++) {
1097	–	dp = da + j;
1098	–	mag0 = mag1 = 0.0;
1099	–	lastsine = 0.0;
1100	–	for (i = 0; i < hp->nt; i++) {
1101	–	#ifdef DEBUG
1102	–	if (dp->t != i \|\| dp->p != j)
1103	–	error(CONSISTENCY,
1104	–	"division order in posgradient");
1105	–	#endif
1106	–	b = bright(dp->v);
1107	–	if (i > 0) {
1108	–	d = dp[-hp->np].r;
1109	–	if (dp[0].r > d) d = dp[0].r;
1110	–	/* sin(t)cos(t)^2 /
1111	–	d = lastsine (1.0 - (double)i/hp->nt);
1112	–	mag0 += d*(b - bright(dp[-hp->np].v));
1113	–	}
1114	–	nextsine = sqrt((double)(i+1)/hp->nt);
1115	–	if (j > 0) {
1116	–	d = dp[-1].r;
1117	–	if (dp[0].r > d) d = dp[0].r;
1118	–	mag1 += d * (nextsine - lastsine) *
1119	–	(b - bright(dp[-1].v));
1120	–	} else {
1121	–	d = dp[hp->np-1].r;
1122	–	if (dp[0].r > d) d = dp[0].r;
1123	–	mag1 += d * (nextsine - lastsine) *
1124	–	(b - bright(dp[hp->np-1].v));
1125	–	}
1126	–	dp += hp->np;
1127	–	lastsine = nextsine;
1128	–	}
1129	–	mag0 = 2.0PI / hp->np;
1130	–	phi = 2.0PI (double)j/hp->np;
1131	–	cosp = tcos(phi); sinp = tsin(phi);
1132	–	xd += mag0cosp - mag1sinp;
1133	–	yd += mag0sinp + mag1cosp;
1134	–	}
1135	–	for (i = 0; i < 3; i++)
1136	–	gv[i] = (xdhp->ux[i] + ydhp->uy[i])(hp->nthp->np)/PI;
1137	–	}
1138	–
1139	–
1140	–	void
1141	–	dirgradient( /* compute direction gradient */
1142	–	FVECT gv,
1143	–	AMBSAMP da, / assumes standard ordering */
1144	–	AMBHEMI *hp
1145	–	)
1146	–	{
1147	–	int i, j;
1148	–	double mag;
1149	–	double phi, xd, yd;
1150	–	AMBSAMP *dp;
1151	–
1152	–	xd = yd = 0.0;
1153	–	for (j = 0; j < hp->np; j++) {
1154	–	dp = da + j;
1155	–	mag = 0.0;
1156	–	for (i = 0; i < hp->nt; i++) {
1157	–	#ifdef DEBUG
1158	–	if (dp->t != i \|\| dp->p != j)
1159	–	error(CONSISTENCY,
1160	–	"division order in dirgradient");
1161	–	#endif
1162	–	/* tan(t) */
1163	–	mag += bright(dp->v)/sqrt(hp->nt/(i+.5) - 1.0);
1164	–	dp += hp->np;
1165	–	}
1166	–	phi = 2.0PI (j+.5)/hp->np + PI/2.0;
1167	–	xd += mag * tcos(phi);
1168	–	yd += mag * tsin(phi);
1169	–	}
1170	–	for (i = 0; i < 3; i++)
1171	–	gv[i] = xdhp->ux[i] + ydhp->uy[i];
1172	–	}
1173	–
1174	–	#endif /* ! NEWAMB */

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Comparing ray/src/rt/ambcomp.c (file contents): Revision 2.70 by greg, Thu May 21 05:54:54 2015 UTC vs. Revision 2.93 by greg, Tue Apr 16 23:32:20 2024 UTC

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Comparing ray/src/rt/ambcomp.c (file contents):
Revision 2.70 by greg, Thu May 21 05:54:54 2015 UTC vs.
Revision 2.93 by greg, Tue Apr 16 23:32:20 2024 UTC