--- ray/src/gen/mkillum2.c	2007/12/05 20:07:34	2.24
+++ ray/src/gen/mkillum2.c	2023/11/17 20:02:07	2.43
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: mkillum2.c,v 2.24 2007/12/05 20:07:34 greg Exp $";
+static const char	RCSid[] = "$Id: mkillum2.c,v 2.43 2023/11/17 20:02:07 greg Exp $";
 #endif
 /*
  * Routines to do the actual calculation for mkillum
@@ -10,8 +10,12 @@ static const char	RCSid[] = "$Id: mkillum2.c,v 2.24 20
 #include  "mkillum.h"
 #include  "face.h"
 #include  "cone.h"
-#include  "random.h"
+#include  "source.h"
+#include  "paths.h"
 
+#ifndef R_EPS
+#define R_EPS		0.005		/* relative epsilon for ray origin */
+#endif
 
 COLORV *	distarr = NULL;		/* distribution array */
 int		distsiz = 0;
@@ -24,14 +28,14 @@ newdist(			/* allocate & clear distribution array */
 {
 	if (siz <= 0) {
 		if (distsiz > 0)
-			free((void *)distarr);
+			free(distarr);
 		distarr = NULL;
 		distsiz = 0;
 		return;
 	}
 	if (distsiz < siz) {
 		if (distsiz > 0)
-			free((void *)distarr);
+			free(distarr);
 		distarr = (COLORV *)malloc(sizeof(COLOR)*siz);
 		if (distarr == NULL)
 			error(SYSTEM, "out of memory in newdist");
@@ -42,7 +46,10 @@ newdist(			/* allocate & clear distribution array */
 
 
 int
-process_ray(RAY *r, int rv)
+process_ray(			/* process a ray result or report error */
+	RAY *r,
+	int rv
+)
 {
 	COLORV	*colp;
 
@@ -52,14 +59,15 @@ process_ray(RAY *r, int rv)
 		error(USER, "ray tracing process died");
 	if (r->rno >= distsiz)
 		error(INTERNAL, "bad returned index in process_ray");
+	smultscolor(r->rcol, r->rcoef);	/* in case it's a source ray */
 	colp = &distarr[r->rno * 3];
-	addcolor(colp, r->rcol);
+	addscolor(colp, r->rcol);
 	return(1);
 }
 
 
 void
-raysamp(	/* queue a ray sample */
+raysamp(			/* queue a ray sample */
 	int  ndx,
 	FVECT  org,
 	FVECT  dir
@@ -73,7 +81,7 @@ raysamp(	/* queue a ray sample */
 	VCOPY(myRay.rorg, org);
 	VCOPY(myRay.rdir, dir);
 	myRay.rmax = .0;
-	rayorigin(&myRay, PRIMARY, NULL, NULL);
+	rayorigin(&myRay, PRIMARY|SPECULAR, NULL, NULL);
 	myRay.rno = ndx;
 					/* queue ray, check result */
 	process_ray(&myRay, ray_pqueue(&myRay));
@@ -81,6 +89,50 @@ raysamp(	/* queue a ray sample */
 
 
 void
+srcsamps(			/* sample sources from this surface position */
+	struct illum_args *il,
+	FVECT org,
+	double eps,
+	MAT4 ixfm
+)
+{
+	int  nalt=1, nazi=1;
+	SRCINDEX  si;
+	RAY  sr;
+	FVECT	v;
+	double  d;
+	int  i, j;
+						/* get sampling density */
+	if (il->sampdens > 0) {
+		i = PI * il->sampdens;
+		nalt = sqrt(i/PI) + .5;
+		nazi = PI*nalt + .5;
+	}
+	initsrcindex(&si);			/* loop over (sub)sources */
+	for ( ; ; ) {
+		VCOPY(sr.rorg, org);		/* pick side to shoot from */
+		samplendx++;			/* increment sample counter */
+		if (!srcray(&sr, NULL, &si))
+			break;			/* end of sources */
+						/* index direction */
+		if (ixfm != NULL)
+			multv3(v, sr.rdir, ixfm);
+		else
+			VCOPY(v, sr.rdir);
+		if (v[2] >= -FTINY)
+			continue;		/* only sample transmission */
+		v[0] = -v[0]; v[1] = -v[1]; v[2] = -v[2];
+		sr.rno = flatindex(v, nalt, nazi);
+		d = nalt*nazi*(1./PI) * v[2];
+		d *= si.dom;			/* solid angle correction */
+		scalescolor(sr.rcoef, d);
+		VSUM(sr.rorg, sr.rorg, sr.rdir, -eps);
+		process_ray(&sr, ray_pqueue(&sr));
+	}
+}
+
+
+void
 rayclean()			/* finish all pending rays */
 {
 	RAY	myRay;
@@ -97,22 +149,14 @@ mkaxes(			/* compute u and v to go with n */
 	FVECT  n
 )
 {
-	register int  i;
-
-	v[0] = v[1] = v[2] = 0.0;
-	for (i = 0; i < 3; i++)
-		if (n[i] < 0.6 && n[i] > -0.6)
-			break;
-	v[i] = 1.0;
-	fcross(u, v, n);
-	normalize(u);
+	getperpendicular(u, n, 1);
 	fcross(v, n, u);
 }
 
 
 static void
 rounddir(		/* compute uniform spherical direction */
-	register FVECT  dv,
+	FVECT  dv,
 	double  alt,
 	double  azi
 )
@@ -145,6 +189,26 @@ flatdir(		/* compute uniform hemispherical direction *
 
 
 int
+flatindex(		/* compute index for hemispherical direction */
+	FVECT	dv,
+	int	nalt,
+	int	nazi
+)
+{
+	double	d;
+	int	i, j;
+	
+	d = 1.0 - dv[2]*dv[2];
+	i = d*nalt;
+	d = atan2(dv[1], dv[0]) * (0.5/PI);
+	if (d < 0.0) d += 1.0;
+	j = d*nazi + 0.5;
+	if (j >= nazi) j = 0;
+	return(i*nazi + j);
+}
+
+
+int
 my_default(	/* default illum action */
 	OBJREC  *ob,
 	struct illum_args  *il,
@@ -166,17 +230,19 @@ my_face(		/* make an illum face */
 	char  *nm
 )
 {
-#define MAXMISS		(5*n*il->nsamps)
 	int  dim[2];
-	int  n, nalt, nazi, h, alti;
+	int  n, nalt, nazi, alti;
 	double  sp[2], r1, r2;
+	int  h;
 	FVECT  dn, org, dir;
 	FVECT  u, v;
 	double  ur[2], vr[2];
+	double  epsilon;
 	MAT4  xfm;
-	int  nmisses;
+	char  xfrot[64];
+	int  nallow;
 	FACE  *fa;
-	register int  i, j;
+	int  i, j;
 				/* get/check arguments */
 	fa = getface(ob);
 	if (fa->area == 0.0) {
@@ -184,23 +250,14 @@ my_face(		/* make an illum face */
 		return(my_default(ob, il, nm));
 	}
 				/* set up sampling */
-	if (il->sd != NULL) {
-		if (!getBSDF_xfm(xfm, fa->norm, il->udir)) {
-			objerror(ob, WARNING, "illegal up direction");
-			freeface(ob);
-			return(my_default(ob, il, nm));
-		}
-		n = il->sd->ninc;
+	if (il->sampdens <= 0) {
+		nalt = nazi = 1;	/* diffuse assumption */
 	} else {
-		if (il->sampdens <= 0) {
-			nalt = nazi = 1;	/* diffuse assumption */
-		} else {
-			n = PI * il->sampdens;
-			nalt = sqrt(n/PI) + .5;
-			nazi = PI*nalt + .5;
-		}
-		n = nazi*nalt;
+		n = PI * il->sampdens;
+		nalt = sqrt(n/PI) + .5;
+		nazi = PI*nalt + .5;
 	}
+	n = nazi*nalt;
 	newdist(n);
 				/* take first edge >= sqrt(area) */
 	for (j = fa->nv-1, i = 0; i < fa->nv; j = i++) {
@@ -229,53 +286,75 @@ my_face(		/* make an illum face */
 	}
 	dim[0] = random();
 				/* sample polygon */
-	nmisses = 0;
+	nallow = 5*n*il->nsamps;
+	epsilon = R_EPS*sqrt(fa->area);
 	for (dim[1] = 0; dim[1] < n; dim[1]++)
 		for (i = 0; i < il->nsamps; i++) {
 					/* randomize direction */
 		    h = ilhash(dim, 2) + i;
-		    if (il->sd != NULL) {
-			r_BSDF_incvec(dir, il->sd, dim[1], urand(h), xfm);
-		    } else {
-			multisamp(sp, 2, urand(h));
-			alti = dim[1]/nazi;
-			r1 = (alti + sp[0])/nalt;
-			r2 = (dim[1] - alti*nazi + sp[1] - .5)/nazi;
-			flatdir(dn, r1, r2);
-			for (j = 0; j < 3; j++)
+		    multisamp(sp, 2, urand(h));
+		    alti = dim[1]/nazi;
+		    r1 = (alti + sp[0])/nalt;
+		    r2 = (dim[1] - alti*nazi + sp[1] - .5)/nazi;
+		    flatdir(dn, r1, r2);
+		    for (j = 0; j < 3; j++)
 			    dir[j] = -dn[0]*u[j] - dn[1]*v[j] -
 						dn[2]*fa->norm[j];
-		    }
 					/* randomize location */
 		    do {
-			multisamp(sp, 2, urand(h+4862+nmisses));
+			multisamp(sp, 2, urand(h+4862+nallow));
 			r1 = ur[0] + (ur[1]-ur[0]) * sp[0];
 			r2 = vr[0] + (vr[1]-vr[0]) * sp[1];
 			for (j = 0; j < 3; j++)
 			    org[j] = r1*u[j] + r2*v[j]
 					+ fa->offset*fa->norm[j];
-		    } while (!inface(org, fa) && nmisses++ < MAXMISS);
-		    if (nmisses > MAXMISS) {
+		    } while (!inface(org, fa) && nallow-- > 0);
+		    if (nallow < 0) {
 			objerror(ob, WARNING, "bad aspect");
 			rayclean();
 			freeface(ob);
 			return(my_default(ob, il, nm));
 		    }
-		    if (il->sd != NULL && DOT(dir, fa->norm) < -FTINY)
-			r1 = -1.0001*il->thick - .0001;
-		    else
-			r1 = .0001;
-		    for (j = 0; j < 3; j++)
-			org[j] += r1*fa->norm[j];
+		    VSUM(org, org, dir, -epsilon);
 					/* send sample */
 		    raysamp(dim[1], org, dir);
 		}
-	rayclean();
-	if (il->sd != NULL) {	/* run distribution through BSDF */
-		nalt = sqrt(il->sd->nout/PI) + .5;
-		nazi = PI*nalt + .5;
-		redistribute(il->sd, nalt, nazi, u, v, fa->norm, xfm);
+				/* add in direct component? */
+	if (il->flags & IL_LIGHT) {
+		MAT4	ixfm;
+		for (i = 3; i--; ) {
+			ixfm[i][0] = u[i];
+			ixfm[i][1] = v[i];
+			ixfm[i][2] = fa->norm[i];
+			ixfm[i][3] = 0.;
+		}
+		ixfm[3][0] = ixfm[3][1] = ixfm[3][2] = 0.;
+		ixfm[3][3] = 1.;
+		dim[0] = random();
+		nallow = 10*il->nsamps;
+		for (i = 0; i < il->nsamps; i++) {
+					/* randomize location */
+		    h = dim[0] + samplendx++;
+		    do {
+			multisamp(sp, 2, urand(h+nallow));
+			r1 = ur[0] + (ur[1]-ur[0]) * sp[0];
+			r2 = vr[0] + (vr[1]-vr[0]) * sp[1];
+			for (j = 0; j < 3; j++)
+			    org[j] = r1*u[j] + r2*v[j]
+					+ fa->offset*fa->norm[j];
+		    } while (!inface(org, fa) && nallow-- > 0);
+		    if (nallow < 0) {
+			objerror(ob, WARNING, "bad aspect");
+			rayclean();
+			freeface(ob);
+			return(my_default(ob, il, nm));
+		    }
+					/* sample source rays */
+		    srcsamps(il, org, epsilon, ixfm);
+		}
 	}
+				/* wait for all rays to finish */
+	rayclean();
 				/* write out the face and its distribution */
 	if (average(il, distarr, n)) {
 		if (il->sampdens > 0)
@@ -286,13 +365,12 @@ my_face(		/* make an illum face */
 				/* clean up */
 	freeface(ob);
 	return(0);
-#undef MAXMISS
 }
 
 
 int
 my_sphere(	/* make an illum sphere */
-	register OBJREC  *ob,
+	OBJREC  *ob,
 	struct illum_args  *il,
 	char  *nm
 )
@@ -302,7 +380,7 @@ my_sphere(	/* make an illum sphere */
 	double  sp[4], r1, r2, r3;
 	FVECT  org, dir;
 	FVECT  u, v;
-	register int  i, j;
+	int  i, j;
 				/* check arguments */
 	if (ob->oargs.nfargs != 4)
 		objerror(ob, USER, "bad # of arguments");
@@ -314,8 +392,6 @@ my_sphere(	/* make an illum sphere */
 		nalt = sqrt(2./PI*n) + .5;
 		nazi = PI/2.*nalt + .5;
 	}
-	if (il->sd != NULL)
-		objerror(ob, WARNING, "BSDF ignored");
 	n = nalt*nazi;
 	newdist(n);
 	dim[0] = random();
@@ -344,6 +420,7 @@ my_sphere(	/* make an illum sphere */
 					/* send sample */
 		    raysamp(dim[1]*nazi+dim[2], org, dir);
 		}
+				/* wait for all rays to finish */
 	rayclean();
 				/* write out the sphere and its distribution */
 	if (average(il, distarr, n)) {
@@ -369,32 +446,27 @@ my_ring(		/* make an illum ring */
 	int  dim[2];
 	int  n, nalt, nazi, alti;
 	double  sp[2], r1, r2, r3;
+	double  epsilon;
 	int  h;
 	FVECT  dn, org, dir;
 	FVECT  u, v;
 	MAT4  xfm;
 	CONE  *co;
-	register int  i, j;
-				/* get/check arguments */
+	int  i, j;
+					/* get/check arguments */
 	co = getcone(ob, 0);
-				/* set up sampling */
-	if (il->sd != NULL) {
-		if (!getBSDF_xfm(xfm, co->ad, il->udir)) {
-			objerror(ob, WARNING, "illegal up direction");
-			freecone(ob);
-			return(my_default(ob, il, nm));
-		}
-		n = il->sd->ninc;
+	if (co == NULL)
+		objerror(ob, USER, "cannot create illum");
+					/* set up sampling */
+	if (il->sampdens <= 0) {
+		nalt = nazi = 1;	/* diffuse assumption */
 	} else {
-		if (il->sampdens <= 0) {
-			nalt = nazi = 1;	/* diffuse assumption */
-		} else {
-			n = PI * il->sampdens;
-			nalt = sqrt(n/PI) + .5;
-			nazi = PI*nalt + .5;
-		}
-		n = nazi*nalt;
+		n = PI * il->sampdens;
+		nalt = sqrt(n/PI) + .5;
+		nazi = PI*nalt + .5;
 	}
+	epsilon = R_EPS*CO_R1(co);
+	n = nazi*nalt;
 	newdist(n);
 	mkaxes(u, v, co->ad);
 	dim[0] = random();
@@ -404,17 +476,13 @@ my_ring(		/* make an illum ring */
 					/* next sample point */
 		    h = ilhash(dim,2) + i;
 					/* randomize direction */
-		    if (il->sd != NULL) {
-			r_BSDF_incvec(dir, il->sd, dim[1], urand(h), xfm);
-		    } else {
-			multisamp(sp, 2, urand(h));
-			alti = dim[1]/nazi;
-			r1 = (alti + sp[0])/nalt;
-			r2 = (dim[1] - alti*nazi + sp[1] - .5)/nazi;
-			flatdir(dn, r1, r2);
-			for (j = 0; j < 3; j++)
-				dir[j] = -dn[0]*u[j] - dn[1]*v[j] - dn[2]*co->ad[j];
-		    }
+		    multisamp(sp, 2, urand(h));
+		    alti = dim[1]/nazi;
+		    r1 = (alti + sp[0])/nalt;
+		    r2 = (dim[1] - alti*nazi + sp[1] - .5)/nazi;
+		    flatdir(dn, r1, r2);
+		    for (j = 0; j < 3; j++)
+			dir[j] = -dn[0]*u[j] - dn[1]*v[j] - dn[2]*co->ad[j];
 					/* randomize location */
 		    multisamp(sp, 2, urand(h+8371));
 		    r3 = sqrt(CO_R0(co)*CO_R0(co) +
@@ -422,22 +490,41 @@ my_ring(		/* make an illum ring */
 		    r2 = 2.*PI*sp[1];
 		    r1 = r3*cos(r2);
 		    r2 = r3*sin(r2);
-		    if (il->sd != NULL && DOT(dir, co->ad) < -FTINY)
-			r3 = -1.0001*il->thick - .0001;
-		    else
-			r3 = .0001;
 		    for (j = 0; j < 3; j++)
 			org[j] = CO_P0(co)[j] + r1*u[j] + r2*v[j] +
-						r3*co->ad[j];
+						epsilon*co->ad[j];
 					/* send sample */
 		    raysamp(dim[1], org, dir);
 		}
-	rayclean();
-	if (il->sd != NULL) {	/* run distribution through BSDF */
-		nalt = sqrt(il->sd->nout/PI) + .5;
-		nazi = PI*nalt + .5;
-		redistribute(il->sd, nalt, nazi, u, v, co->ad, xfm);
+				/* add in direct component? */
+	if (il->flags & IL_LIGHT) {
+		MAT4	ixfm;
+		for (i = 3; i--; ) {
+			ixfm[i][0] = u[i];
+			ixfm[i][1] = v[i];
+			ixfm[i][2] = co->ad[i];
+			ixfm[i][3] = 0.;
+		}
+		ixfm[3][0] = ixfm[3][1] = ixfm[3][2] = 0.;
+		ixfm[3][3] = 1.;
+		dim[0] = random();
+		for (i = 0; i < il->nsamps; i++) {
+					/* randomize location */
+		    h = dim[0] + samplendx++;
+		    multisamp(sp, 2, urand(h));
+		    r3 = sqrt(CO_R0(co)*CO_R0(co) +
+			    sp[0]*(CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co)));
+		    r2 = 2.*PI*sp[1];
+		    r1 = r3*cos(r2);
+		    r2 = r3*sin(r2);
+		    for (j = 0; j < 3; j++)
+			org[j] = CO_P0(co)[j] + r1*u[j] + r2*v[j];
+					/* sample source rays */
+		    srcsamps(il, org, epsilon, ixfm);
+		}
 	}
+				/* wait for all rays to finish */
+	rayclean();
 				/* write out the ring and its distribution */
 	if (average(il, distarr, n)) {
 		if (il->sampdens > 0)