--- ray/src/rt/ambcomp.c	2019/02/26 00:37:54	2.84
+++ ray/src/rt/ambcomp.c	2019/05/14 17:39:10	2.85
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: ambcomp.c,v 2.84 2019/02/26 00:37:54 greg Exp $";
+static const char	RCSid[] = "$Id: ambcomp.c,v 2.85 2019/05/14 17:39:10 greg Exp $";
 #endif
 /*
  * Routines to compute "ambient" values using Monte Carlo
@@ -21,8 +21,6 @@ static const char	RCSid[] = "$Id: ambcomp.c,v 2.84 201
 #include  "ambient.h"
 #include  "random.h"
 
-#ifndef OLDAMB
-
 extern void		SDsquare2disk(double ds[2], double seedx, double seedy);
 
 typedef struct {
@@ -778,427 +776,3 @@ doambient(				/* compute ambient component */
 	return(1);
 }
 
-
-#else /* ! NEWAMB */
-
-
-void
-inithemi(			/* initialize sampling hemisphere */
-	AMBHEMI  *hp,
-	COLOR ac,
-	RAY  *r,
-	double  wt
-)
-{
-	double	d;
-	int  i;
-					/* set number of divisions */
-	if (ambacc <= FTINY &&
-			wt > (d = 0.8*intens(ac)*r->rweight/(ambdiv*minweight)))
-		wt = d;			/* avoid ray termination */
-	hp->nt = sqrt(ambdiv * wt / PI) + 0.5;
-	i = ambacc > FTINY ? 3 : 1;	/* minimum number of samples */
-	if (hp->nt < i)
-		hp->nt = i;
-	hp->np = PI * hp->nt + 0.5;
-					/* set number of super-samples */
-	hp->ns = ambssamp * wt + 0.5;
-					/* assign coefficient */
-	copycolor(hp->acoef, ac);
-	d = 1.0/(hp->nt*hp->np);
-	scalecolor(hp->acoef, d);
-					/* make axes */
-	VCOPY(hp->uz, r->ron);
-	hp->uy[0] = hp->uy[1] = hp->uy[2] = 0.0;
-	for (i = 0; i < 3; i++)
-		if (hp->uz[i] < 0.6 && hp->uz[i] > -0.6)
-			break;
-	if (i >= 3)
-		error(CONSISTENCY, "bad ray direction in inithemi");
-	hp->uy[i] = 1.0;
-	fcross(hp->ux, hp->uy, hp->uz);
-	normalize(hp->ux);
-	fcross(hp->uy, hp->uz, hp->ux);
-}
-
-
-int
-divsample(				/* sample a division */
-	AMBSAMP  *dp,
-	AMBHEMI  *h,
-	RAY  *r
-)
-{
-	RAY  ar;
-	int  hlist[3];
-	double  spt[2];
-	double  xd, yd, zd;
-	double  b2;
-	double  phi;
-	int  i;
-					/* ambient coefficient for weight */
-	if (ambacc > FTINY)
-		setcolor(ar.rcoef, AVGREFL, AVGREFL, AVGREFL);
-	else
-		copycolor(ar.rcoef, h->acoef);
-	if (rayorigin(&ar, AMBIENT, r, ar.rcoef) < 0)
-		return(-1);
-	if (ambacc > FTINY) {
-		multcolor(ar.rcoef, h->acoef);
-		scalecolor(ar.rcoef, 1./AVGREFL);
-	}
-	hlist[0] = r->rno;
-	hlist[1] = dp->t;
-	hlist[2] = dp->p;
-	multisamp(spt, 2, urand(ilhash(hlist,3)+dp->n));
-	zd = sqrt((dp->t + spt[0])/h->nt);
-	phi = 2.0*PI * (dp->p + spt[1])/h->np;
-	xd = tcos(phi) * zd;
-	yd = tsin(phi) * zd;
-	zd = sqrt(1.0 - zd*zd);
-	for (i = 0; i < 3; i++)
-		ar.rdir[i] =	xd*h->ux[i] +
-				yd*h->uy[i] +
-				zd*h->uz[i];
-	checknorm(ar.rdir);
-	dimlist[ndims++] = dp->t*h->np + dp->p + 90171;
-	rayvalue(&ar);
-	ndims--;
-	multcolor(ar.rcol, ar.rcoef);	/* apply coefficient */
-	addcolor(dp->v, ar.rcol);
-					/* use rxt to improve gradient calc */
-	if (ar.rxt > FTINY && ar.rxt < FHUGE)
-		dp->r += 1.0/ar.rxt;
-					/* (re)initialize error */
-	if (dp->n++) {
-		b2 = bright(dp->v)/dp->n - bright(ar.rcol);
-		b2 = b2*b2 + dp->k*((dp->n-1)*(dp->n-1));
-		dp->k = b2/(dp->n*dp->n);
-	} else
-		dp->k = 0.0;
-	return(0);
-}
-
-
-static int
-ambcmp(					/* decreasing order */
-	const void *p1,
-	const void *p2
-)
-{
-	const AMBSAMP	*d1 = (const AMBSAMP *)p1;
-	const AMBSAMP	*d2 = (const AMBSAMP *)p2;
-
-	if (d1->k < d2->k)
-		return(1);
-	if (d1->k > d2->k)
-		return(-1);
-	return(0);
-}
-
-
-static int
-ambnorm(				/* standard order */
-	const void *p1,
-	const void *p2
-)
-{
-	const AMBSAMP	*d1 = (const AMBSAMP *)p1;
-	const AMBSAMP	*d2 = (const AMBSAMP *)p2;
-	int	c;
-
-	if ( (c = d1->t - d2->t) )
-		return(c);
-	return(d1->p - d2->p);
-}
-
-
-double
-doambient(				/* compute ambient component */
-	COLOR  rcol,
-	RAY  *r,
-	double  wt,
-	FVECT  pg,
-	FVECT  dg
-)
-{
-	double  b, d=0;
-	AMBHEMI  hemi;
-	AMBSAMP  *div;
-	AMBSAMP  dnew;
-	double  acol[3];
-	AMBSAMP  *dp;
-	double  arad;
-	int  divcnt;
-	int  i, j;
-					/* initialize hemisphere */
-	inithemi(&hemi, rcol, r, wt);
-	divcnt = hemi.nt * hemi.np;
-					/* initialize */
-	if (pg != NULL)
-		pg[0] = pg[1] = pg[2] = 0.0;
-	if (dg != NULL)
-		dg[0] = dg[1] = dg[2] = 0.0;
-	setcolor(rcol, 0.0, 0.0, 0.0);
-	if (divcnt == 0)
-		return(0.0);
-					/* allocate super-samples */
-	if (hemi.ns > 0 || pg != NULL || dg != NULL) {
-		div = (AMBSAMP *)malloc(divcnt*sizeof(AMBSAMP));
-		if (div == NULL)
-			error(SYSTEM, "out of memory in doambient");
-	} else
-		div = NULL;
-					/* sample the divisions */
-	arad = 0.0;
-	acol[0] = acol[1] = acol[2] = 0.0;
-	if ((dp = div) == NULL)
-		dp = &dnew;
-	divcnt = 0;
-	for (i = 0; i < hemi.nt; i++)
-		for (j = 0; j < hemi.np; j++) {
-			dp->t = i; dp->p = j;
-			setcolor(dp->v, 0.0, 0.0, 0.0);
-			dp->r = 0.0;
-			dp->n = 0;
-			if (divsample(dp, &hemi, r) < 0) {
-				if (div != NULL)
-					dp++;
-				continue;
-			}
-			arad += dp->r;
-			divcnt++;
-			if (div != NULL)
-				dp++;
-			else
-				addcolor(acol, dp->v);
-		}
-	if (!divcnt) {
-		if (div != NULL)
-			free((void *)div);
-		return(0.0);		/* no samples taken */
-	}
-	if (divcnt < hemi.nt*hemi.np) {
-		pg = dg = NULL;		/* incomplete sampling */
-		hemi.ns = 0;
-	} else if (arad > FTINY && divcnt/arad < minarad) {
-		hemi.ns = 0;		/* close enough */
-	} else if (hemi.ns > 0) {	/* else perform super-sampling? */
-		comperrs(div, &hemi);			/* compute errors */
-		qsort(div, divcnt, sizeof(AMBSAMP), ambcmp);	/* sort divs */
-						/* super-sample */
-		for (i = hemi.ns; i > 0; i--) {
-			dnew = *div;
-			if (divsample(&dnew, &hemi, r) < 0) {
-				dp++;
-				continue;
-			}
-			dp = div;		/* reinsert */
-			j = divcnt < i ? divcnt : i;
-			while (--j > 0 && dnew.k < dp[1].k) {
-				*dp = *(dp+1);
-				dp++;
-			}
-			*dp = dnew;
-		}
-		if (pg != NULL || dg != NULL)	/* restore order */
-			qsort(div, divcnt, sizeof(AMBSAMP), ambnorm);
-	}
-					/* compute returned values */
-	if (div != NULL) {
-		arad = 0.0;		/* note: divcnt may be < nt*np */
-		for (i = hemi.nt*hemi.np, dp = div; i-- > 0; dp++) {
-			arad += dp->r;
-			if (dp->n > 1) {
-				b = 1.0/dp->n;
-				scalecolor(dp->v, b);
-				dp->r *= b;
-				dp->n = 1;
-			}
-			addcolor(acol, dp->v);
-		}
-		b = bright(acol);
-		if (b > FTINY) {
-			b = 1.0/b;	/* compute & normalize gradient(s) */
-			if (pg != NULL) {
-				posgradient(pg, div, &hemi);
-				for (i = 0; i < 3; i++)
-					pg[i] *= b;
-			}
-			if (dg != NULL) {
-				dirgradient(dg, div, &hemi);
-				for (i = 0; i < 3; i++)
-					dg[i] *= b;
-			}
-		}
-		free((void *)div);
-	}
-	copycolor(rcol, acol);
-	if (arad <= FTINY)
-		arad = maxarad;
-	else
-		arad = (divcnt+hemi.ns)/arad;
-	if (pg != NULL) {		/* reduce radius if gradient large */
-		d = DOT(pg,pg);
-		if (d*arad*arad > 1.0)
-			arad = 1.0/sqrt(d);
-	}
-	if (arad < minarad) {
-		arad = minarad;
-		if (pg != NULL && d*arad*arad > 1.0) {	/* cap gradient */
-			d = 1.0/arad/sqrt(d);
-			for (i = 0; i < 3; i++)
-				pg[i] *= d;
-		}
-	}
-	if ((arad /= sqrt(wt)) > maxarad)
-		arad = maxarad;
-	return(arad);
-}
-
-
-void
-comperrs(			/* compute initial error estimates */
-	AMBSAMP  *da,	/* assumes standard ordering */
-	AMBHEMI  *hp
-)
-{
-	double  b, b2;
-	int  i, j;
-	AMBSAMP  *dp;
-				/* sum differences from neighbors */
-	dp = da;
-	for (i = 0; i < hp->nt; i++)
-		for (j = 0; j < hp->np; j++) {
-#ifdef  DEBUG
-			if (dp->t != i || dp->p != j)
-				error(CONSISTENCY,
-					"division order in comperrs");
-#endif
-			b = bright(dp[0].v);
-			if (i > 0) {		/* from above */
-				b2 = bright(dp[-hp->np].v) - b;
-				b2 *= b2 * 0.25;
-				dp[0].k += b2;
-				dp[-hp->np].k += b2;
-			}
-			if (j > 0) {		/* from behind */
-				b2 = bright(dp[-1].v) - b;
-				b2 *= b2 * 0.25;
-				dp[0].k += b2;
-				dp[-1].k += b2;
-			} else {		/* around */
-				b2 = bright(dp[hp->np-1].v) - b;
-				b2 *= b2 * 0.25;
-				dp[0].k += b2;
-				dp[hp->np-1].k += b2;
-			}
-			dp++;
-		}
-				/* divide by number of neighbors */
-	dp = da;
-	for (j = 0; j < hp->np; j++)		/* top row */
-		(dp++)->k *= 1.0/3.0;
-	if (hp->nt < 2)
-		return;
-	for (i = 1; i < hp->nt-1; i++)		/* central region */
-		for (j = 0; j < hp->np; j++)
-			(dp++)->k *= 0.25;
-	for (j = 0; j < hp->np; j++)		/* bottom row */
-		(dp++)->k *= 1.0/3.0;
-}
-
-
-void
-posgradient(					/* compute position gradient */
-	FVECT  gv,
-	AMBSAMP  *da,			/* assumes standard ordering */
-	AMBHEMI  *hp
-)
-{
-	int  i, j;
-	double  nextsine, lastsine, b, d;
-	double  mag0, mag1;
-	double  phi, cosp, sinp, xd, yd;
-	AMBSAMP  *dp;
-
-	xd = yd = 0.0;
-	for (j = 0; j < hp->np; j++) {
-		dp = da + j;
-		mag0 = mag1 = 0.0;
-		lastsine = 0.0;
-		for (i = 0; i < hp->nt; i++) {
-#ifdef  DEBUG
-			if (dp->t != i || dp->p != j)
-				error(CONSISTENCY,
-					"division order in posgradient");
-#endif
-			b = bright(dp->v);
-			if (i > 0) {
-				d = dp[-hp->np].r;
-				if (dp[0].r > d) d = dp[0].r;
-							/* sin(t)*cos(t)^2 */
-				d *= lastsine * (1.0 - (double)i/hp->nt);
-				mag0 += d*(b - bright(dp[-hp->np].v));
-			}
-			nextsine = sqrt((double)(i+1)/hp->nt);
-			if (j > 0) {
-				d = dp[-1].r;
-				if (dp[0].r > d) d = dp[0].r;
-				mag1 += d * (nextsine - lastsine) *
-						(b - bright(dp[-1].v));
-			} else {
-				d = dp[hp->np-1].r;
-				if (dp[0].r > d) d = dp[0].r;
-				mag1 += d * (nextsine - lastsine) *
-						(b - bright(dp[hp->np-1].v));
-			}
-			dp += hp->np;
-			lastsine = nextsine;
-		}
-		mag0 *= 2.0*PI / hp->np;
-		phi = 2.0*PI * (double)j/hp->np;
-		cosp = tcos(phi); sinp = tsin(phi);
-		xd += mag0*cosp - mag1*sinp;
-		yd += mag0*sinp + mag1*cosp;
-	}
-	for (i = 0; i < 3; i++)
-		gv[i] = (xd*hp->ux[i] + yd*hp->uy[i])*(hp->nt*hp->np)/PI;
-}
-
-
-void
-dirgradient(					/* compute direction gradient */
-	FVECT  gv,
-	AMBSAMP  *da,			/* assumes standard ordering */
-	AMBHEMI  *hp
-)
-{
-	int  i, j;
-	double  mag;
-	double  phi, xd, yd;
-	AMBSAMP  *dp;
-
-	xd = yd = 0.0;
-	for (j = 0; j < hp->np; j++) {
-		dp = da + j;
-		mag = 0.0;
-		for (i = 0; i < hp->nt; i++) {
-#ifdef  DEBUG
-			if (dp->t != i || dp->p != j)
-				error(CONSISTENCY,
-					"division order in dirgradient");
-#endif
-							/* tan(t) */
-			mag += bright(dp->v)/sqrt(hp->nt/(i+.5) - 1.0);
-			dp += hp->np;
-		}
-		phi = 2.0*PI * (j+.5)/hp->np + PI/2.0;
-		xd += mag * tcos(phi);
-		yd += mag * tsin(phi);
-	}
-	for (i = 0; i < 3; i++)
-		gv[i] = xd*hp->ux[i] + yd*hp->uy[i];
-}
-
-#endif	/* ! NEWAMB */