--- ray/src/cv/bsdfinterp.c	2012/10/20 07:02:00	2.2
+++ ray/src/cv/bsdfinterp.c	2013/06/29 21:03:25	2.11
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: bsdfinterp.c,v 2.2 2012/10/20 07:02:00 greg Exp $";
+static const char RCSid[] = "$Id: bsdfinterp.c,v 2.11 2013/06/29 21:03:25 greg Exp $";
 #endif
 /*
  * Interpolate BSDF data from radial basis functions in advection mesh.
@@ -13,141 +13,7 @@ static const char RCSid[] = "$Id: bsdfinterp.c,v 2.2 2
 #include <string.h>
 #include <math.h>
 #include "bsdfrep.h"
-				/* migration edges drawn in raster fashion */
-MIGRATION		*mig_grid[GRIDRES][GRIDRES];
 
-#ifdef DEBUG
-#include "random.h"
-#include "bmpfile.h"
-/* Hash pointer to byte value (must return 0 for NULL) */
-static int
-byte_hash(const void *p)
-{
-	size_t	h = (size_t)p;
-	h ^= (size_t)p >> 8;
-	h ^= (size_t)p >> 16;
-	h ^= (size_t)p >> 24;
-	return(h & 0xff);
-}
-/* Write out BMP image showing edges */
-static void
-write_edge_image(const char *fname)
-{
-	BMPHeader	*hdr = BMPmappedHeader(GRIDRES, GRIDRES, 0, 256);
-	BMPWriter	*wtr;
-	int		i, j;
-
-	fprintf(stderr, "Writing incident mesh drawing to '%s'\n", fname);
-	hdr->compr = BI_RLE8;
-	for (i = 256; --i; ) {			/* assign random color map */
-		hdr->palette[i].r = random() & 0xff;
-		hdr->palette[i].g = random() & 0xff;
-		hdr->palette[i].b = random() & 0xff;
-						/* reject dark colors */
-		i += (hdr->palette[i].r + hdr->palette[i].g +
-						hdr->palette[i].b < 128);
-	}
-	hdr->palette[0].r = hdr->palette[0].g = hdr->palette[0].b = 0;
-						/* open output */
-	wtr = BMPopenOutputFile(fname, hdr);
-	if (wtr == NULL) {
-		free(hdr);
-		return;
-	}
-	for (i = 0; i < GRIDRES; i++) {		/* write scanlines */
-		for (j = 0; j < GRIDRES; j++)
-			wtr->scanline[j] = byte_hash(mig_grid[i][j]);
-		if (BMPwriteScanline(wtr) != BIR_OK)
-			break;
-	}
-	BMPcloseOutput(wtr);			/* close & clean up */
-}
-#endif
-
-/* Draw edge list into mig_grid array */
-void
-draw_edges(void)
-{
-	int		nnull = 0, ntot = 0;
-	MIGRATION	*ej;
-	int		p0[2], p1[2];
-
-	memset(mig_grid, 0, sizeof(mig_grid));
-	for (ej = mig_list; ej != NULL; ej = ej->next) {
-		++ntot;
-		pos_from_vec(p0, ej->rbfv[0]->invec);
-		pos_from_vec(p1, ej->rbfv[1]->invec);
-		if ((p0[0] == p1[0]) & (p0[1] == p1[1])) {
-			++nnull;
-			mig_grid[p0[0]][p0[1]] = ej;
-			continue;
-		}
-		if (abs(p1[0]-p0[0]) > abs(p1[1]-p0[1])) {
-			const int	xstep = 2*(p1[0] > p0[0]) - 1;
-			const double	ystep = (double)((p1[1]-p0[1])*xstep) /
-							(double)(p1[0]-p0[0]);
-			int		x;
-			double		y;
-			for (x = p0[0], y = p0[1]+.5; x != p1[0];
-						x += xstep, y += ystep)
-				mig_grid[x][(int)y] = ej;
-			mig_grid[x][(int)y] = ej;
-		} else {
-			const int	ystep = 2*(p1[1] > p0[1]) - 1;
-			const double	xstep = (double)((p1[0]-p0[0])*ystep) /
-							(double)(p1[1]-p0[1]);
-			int		y;
-			double		x;
-			for (y = p0[1], x = p0[0]+.5; y != p1[1];
-						y += ystep, x += xstep)
-				mig_grid[(int)x][y] = ej;
-			mig_grid[(int)x][y] = ej;
-		}
-	}
-	if (nnull)
-		fprintf(stderr, "Warning: %d of %d edges are null\n",
-				nnull, ntot);
-#ifdef DEBUG
-	write_edge_image("bsdf_edges.bmp");
-#endif
-}
-
-/* Identify enclosing triangle for this position (flood fill raster check) */
-static int
-identify_tri(MIGRATION *miga[3], unsigned char vmap[GRIDRES][(GRIDRES+7)/8],
-			int px, int py)
-{
-	const int	btest = 1<<(py&07);
-
-	if (vmap[px][py>>3] & btest)		/* already visited here? */
-		return(1);
-						/* else mark it */
-	vmap[px][py>>3] |= btest;
-
-	if (mig_grid[px][py] != NULL) {		/* are we on an edge? */
-		int	i;
-		for (i = 0; i < 3; i++) {
-			if (miga[i] == mig_grid[px][py])
-				return(1);
-			if (miga[i] != NULL)
-				continue;
-			miga[i] = mig_grid[px][py];
-			return(1);
-		}
-		return(0);			/* outside triangle! */
-	}
-						/* check neighbors (flood) */
-	if (px > 0 && !identify_tri(miga, vmap, px-1, py))
-		return(0);
-	if (px < GRIDRES-1 && !identify_tri(miga, vmap, px+1, py))
-		return(0);
-	if (py > 0 && !identify_tri(miga, vmap, px, py-1))
-		return(0);
-	if (py < GRIDRES-1 && !identify_tri(miga, vmap, px, py+1))
-		return(0);
-	return(1);				/* this neighborhood done */
-}
-
 /* Insert vertex in ordered list */
 static void
 insert_vert(RBFNODE **vlist, RBFNODE *v)
@@ -185,7 +51,7 @@ order_triangle(MIGRATION *miga[3])
 		insert_vert(vert, miga[i]->rbfv[1]);
 	}
 						/* should be just 3 vertices */
-	if ((vert[3] == NULL) | (vert[4] != NULL))
+	if ((vert[2] == NULL) | (vert[3] != NULL))
 		return(0);
 						/* identify edge 0 */
 	for (i = 3; i--; )
@@ -219,82 +85,175 @@ order_triangle(MIGRATION *miga[3])
 	return(1);
 }
 
+/* Determine if we are close enough to an edge */
+static int
+on_edge(const MIGRATION *ej, const FVECT ivec)
+{
+	double	cos_a, cos_b, cos_c, cos_aplusb;
+					/* use triangle inequality */
+	cos_a = DOT(ej->rbfv[0]->invec, ivec);
+	if (cos_a <= 0)
+		return(0);
+
+	cos_b = DOT(ej->rbfv[1]->invec, ivec);
+	if (cos_b <= 0)
+		return(0);
+
+	cos_aplusb = cos_a*cos_b - sqrt((1.-cos_a*cos_a)*(1.-cos_b*cos_b));
+	if (cos_aplusb <= 0)
+		return(0);
+
+	cos_c = DOT(ej->rbfv[0]->invec, ej->rbfv[1]->invec);
+
+	return(cos_c - cos_aplusb < .001);
+}
+
+/* Determine if we are inside the given triangle */
+static int
+in_tri(const RBFNODE *v1, const RBFNODE *v2, const RBFNODE *v3, const FVECT p)
+{
+	FVECT	vc;
+	int	sgn1, sgn2, sgn3;
+					/* signed volume test */
+	VCROSS(vc, v1->invec, v2->invec);
+	sgn1 = (DOT(p, vc) > 0);
+	VCROSS(vc, v2->invec, v3->invec);
+	sgn2 = (DOT(p, vc) > 0);
+	if (sgn1 != sgn2)
+		return(0);
+	VCROSS(vc, v3->invec, v1->invec);
+	sgn3 = (DOT(p, vc) > 0);
+	return(sgn2 == sgn3);
+}
+
+/* Test (and set) bitmap for edge */
+static int
+check_edge(unsigned char *emap, int nedges, const MIGRATION *mig, int mark)
+{
+	int	ejndx, bit2check;
+
+	if (mig->rbfv[0]->ord > mig->rbfv[1]->ord)
+		ejndx = mig->rbfv[1]->ord + (nedges-1)*mig->rbfv[0]->ord;
+	else
+		ejndx = mig->rbfv[0]->ord + (nedges-1)*mig->rbfv[1]->ord;
+
+	bit2check = 1<<(ejndx&07);
+
+	if (emap[ejndx>>3] & bit2check)
+		return(0);
+	if (mark)
+		emap[ejndx>>3] |= bit2check;
+	return(1);
+}
+
+/* Compute intersection with the given position over remaining mesh */
+static int
+in_mesh(MIGRATION *miga[3], unsigned char *emap, int nedges,
+			const FVECT ivec, MIGRATION *mig)
+{
+	RBFNODE		*tv[2];
+	MIGRATION	*sej[2], *dej[2];
+	int		i;
+						/* check visitation record */
+	if (!check_edge(emap, nedges, mig, 1))
+		return(0);
+	if (on_edge(mig, ivec)) {
+		miga[0] = mig;			/* close enough to edge */
+		return(1);
+	}
+	if (!get_triangles(tv, mig))		/* do triangles either side? */
+		return(0);
+	for (i = 2; i--; ) {			/* identify edges to check */
+		MIGRATION	*ej;
+		sej[i] = dej[i] = NULL;
+		if (tv[i] == NULL)
+			continue;
+		for (ej = tv[i]->ejl; ej != NULL; ej = nextedge(tv[i],ej)) {
+			RBFNODE	*rbfop = opp_rbf(tv[i],ej);
+			if (rbfop == mig->rbfv[0]) {
+				if (check_edge(emap, nedges, ej, 0))
+					sej[i] = ej;
+			} else if (rbfop == mig->rbfv[1]) {
+				if (check_edge(emap, nedges, ej, 0))
+					dej[i] = ej;
+			}
+		}
+	}
+	for (i = 2; i--; ) {			/* check triangles just once */
+		if (sej[i] != NULL && in_mesh(miga, emap, nedges, ivec, sej[i]))
+			return(1);
+		if (dej[i] != NULL && in_mesh(miga, emap, nedges, ivec, dej[i]))
+			return(1);
+		if ((sej[i] == NULL) | (dej[i] == NULL))
+			continue;
+		if (in_tri(mig->rbfv[0], mig->rbfv[1], tv[i], ivec)) {
+			miga[0] = mig;
+			miga[1] = sej[i];
+			miga[2] = dej[i];
+			return(1);
+		}
+	}
+	return(0);				/* not near this edge */
+}
+
 /* Find edge(s) for interpolating the given vector, applying symmetry */
 int
 get_interp(MIGRATION *miga[3], FVECT invec)
 {
 	miga[0] = miga[1] = miga[2] = NULL;
 	if (single_plane_incident) {		/* isotropic BSDF? */
-		RBFNODE	*rbf;			/* find edge we're on */
-		for (rbf = dsf_list; rbf != NULL; rbf = rbf->next) {
-			if (input_orient*rbf->invec[2] < input_orient*invec[2])
-				break;
-			if (rbf->next != NULL &&
-					input_orient*rbf->next->invec[2] <
+	    RBFNODE	*rbf;			/* find edge we're on */
+	    for (rbf = dsf_list; rbf != NULL; rbf = rbf->next) {
+		if (input_orient*rbf->invec[2] < input_orient*invec[2])
+			break;
+		if (rbf->next != NULL && input_orient*rbf->next->invec[2] <
 							input_orient*invec[2]) {
-				for (miga[0] = rbf->ejl; miga[0] != NULL;
-						miga[0] = nextedge(rbf,miga[0]))
-					if (opp_rbf(rbf,miga[0]) == rbf->next)
-						return(0);
-				break;
+		    for (miga[0] = rbf->ejl; miga[0] != NULL;
+					miga[0] = nextedge(rbf,miga[0]))
+			if (opp_rbf(rbf,miga[0]) == rbf->next) {
+				double	nf = 1. - rbf->invec[2]*rbf->invec[2];
+				if (nf > FTINY) {	/* rotate to match */
+					nf = sqrt((1.-invec[2]*invec[2])/nf);
+					invec[0] = nf*rbf->invec[0];
+					invec[1] = nf*rbf->invec[1];
+				}
+				return(0);
 			}
+		    break;
 		}
-		return(-1);			/* outside range! */
+	    }
+	    return(-1);				/* outside range! */
 	}
 	{					/* else use triangle mesh */
-		const int	sym = use_symmetry(invec);
-		unsigned char	floodmap[GRIDRES][(GRIDRES+7)/8];
-		int		pstart[2];
-		RBFNODE		*vother;
-		MIGRATION	*ej;
-		int		i;
-
-		pos_from_vec(pstart, invec);
-		memset(floodmap, 0, sizeof(floodmap));
-						/* call flooding function */
-		if (!identify_tri(miga, floodmap, pstart[0], pstart[1]))
-			return(-1);		/* outside mesh */
-		if ((miga[0] == NULL) | (miga[2] == NULL))
-			return(-1);		/* should never happen */
-		if (miga[1] == NULL)
-			return(sym);		/* on edge */
-						/* verify triangle */
-		if (!order_triangle(miga)) {
+		int		sym = use_symmetry(invec);
+		int		nedges = 0;
+		MIGRATION	*mep;
+		unsigned char	*emap;
+						/* clear visitation map */
+		for (mep = mig_list; mep != NULL; mep = mep->next)
+			++nedges;
+		emap = (unsigned char *)calloc((nedges*(nedges-1) + 7)>>3, 1);
+		if (emap == NULL) {
+			fprintf(stderr, "%s: Out of memory in get_interp()\n",
+					progname);
+			exit(1);
+		}
+						/* identify intersection  */
+		if (!in_mesh(miga, emap, nedges, invec, mig_list)) {
 #ifdef DEBUG
-			fputs("Munged triangle in get_interp()\n", stderr);
+			fprintf(stderr,
+			"Incident angle (%.1f,%.1f) deg. outside mesh\n",
+					get_theta180(invec), get_phi360(invec));
 #endif
-			vother = NULL;		/* find triangle from edge */
-			for (i = 3; i--; ) {
-			    RBFNODE	*tpair[2];
-			    if (get_triangles(tpair, miga[i]) &&
-					(vother = tpair[ is_rev_tri(
-							miga[i]->rbfv[0]->invec,
-							miga[i]->rbfv[1]->invec,
-							invec) ]) != NULL)
-					break;
-			}
-			if (vother == NULL) {	/* couldn't find 3rd vertex */
+			sym = -1;		/* outside mesh */
+		} else if (miga[1] != NULL &&
+				(miga[2] == NULL || !order_triangle(miga))) {
 #ifdef DEBUG
-				fputs("No triangle in get_interp()\n", stderr);
+			fputs("Munged triangle in get_interp()\n", stderr);
 #endif
-				return(-1);
-			}
-						/* reassign other two edges */
-			for (ej = vother->ejl; ej != NULL;
-						ej = nextedge(vother,ej)) {
-				RBFNODE	*vorig = opp_rbf(vother,ej);
-				if (vorig == miga[i]->rbfv[0])
-					miga[(i+1)%3] = ej;
-				else if (vorig == miga[i]->rbfv[1])
-					miga[(i+2)%3] = ej;
-			}
-			if (!order_triangle(miga)) {
-#ifdef DEBUG
-				fputs("Bad triangle in get_interp()\n", stderr);
-#endif
-				return(-1);
-			}
+			sym = -1;
 		}
+		free(emap);
 		return(sym);			/* return in standard order */
 	}
 }
@@ -307,22 +266,24 @@ e_advect_rbf(const MIGRATION *mig, const FVECT invec)
 	int		n, i, j;
 	double		t, full_dist;
 						/* get relative position */
-	t = acos(DOT(invec, mig->rbfv[0]->invec));
-	if (t < M_PI/GRIDRES) {			/* near first DSF */
+	t = Acos(DOT(invec, mig->rbfv[0]->invec));
+	if (t < M_PI/grid_res) {		/* near first DSF */
 		n = sizeof(RBFNODE) + sizeof(RBFVAL)*(mig->rbfv[0]->nrbf-1);
 		rbf = (RBFNODE *)malloc(n);
 		if (rbf == NULL)
 			goto memerr;
 		memcpy(rbf, mig->rbfv[0], n);	/* just duplicate */
+		rbf->next = NULL; rbf->ejl = NULL;
 		return(rbf);
 	}
 	full_dist = acos(DOT(mig->rbfv[0]->invec, mig->rbfv[1]->invec));
-	if (t > full_dist-M_PI/GRIDRES) {	/* near second DSF */
+	if (t > full_dist-M_PI/grid_res) {	/* near second DSF */
 		n = sizeof(RBFNODE) + sizeof(RBFVAL)*(mig->rbfv[1]->nrbf-1);
 		rbf = (RBFNODE *)malloc(n);
 		if (rbf == NULL)
 			goto memerr;
 		memcpy(rbf, mig->rbfv[1], n);	/* just duplicate */
+		rbf->next = NULL; rbf->ejl = NULL;
 		return(rbf);
 	}
 	t /= full_dist;	
@@ -393,7 +354,10 @@ advect_rbf(const FVECT invec)
 		return(NULL);
 	if (miga[1] == NULL) {			/* advect along edge? */
 		rbf = e_advect_rbf(miga[0], sivec);
-		rev_rbf_symmetry(rbf, sym);
+		if (single_plane_incident)
+			rotate_rbf(rbf, invec);
+		else
+			rev_rbf_symmetry(rbf, sym);
 		return(rbf);
 	}
 #ifdef DEBUG
@@ -420,7 +384,7 @@ advect_rbf(const FVECT invec)
 	    for (j = 0; j < mtx_ncols(miga[0]); j++)
 		for (k = (mtx_coef(miga[0],i,j) > FTINY) *
 					mtx_ncols(miga[2]); k--; )
-			n += (mtx_coef(miga[2],i,k) > FTINY &&
+			n += (mtx_coef(miga[2],i,k) > FTINY ||
 				mtx_coef(miga[1],j,k) > FTINY);
 #ifdef DEBUG
 	fprintf(stderr, "Input RBFs have %d, %d, %d nodes -> output has %d\n",
@@ -461,17 +425,16 @@ advect_rbf(const FVECT invec)
 		    float		mc = mtx_coef(miga[2],i,k);
 		    const RBFVAL	*rbf2k;
 		    double		rad2k;
-		    FVECT		vout;
 		    int			pos[2];
-		    if ((mb <= FTINY) | (mc <= FTINY))
+		    if ((mb <= FTINY) & (mc <= FTINY))
 			continue;
 		    rbf2k = &miga[2]->rbfv[1]->rbfa[k];
 		    rbf->rbfa[n].peak = w0i * ma * (mb*mbfact + mc*mcfact);
 		    rad2k = R2ANG(rbf2k->crad);
 		    rbf->rbfa[n].crad = ANG2R(sqrt(srad2 + t*rad2k*rad2k));
 		    ovec_from_pos(v2, rbf2k->gx, rbf2k->gy);
-		    geodesic(vout, v1, v2, t, GEOD_REL);
-		    pos_from_vec(pos, vout);
+		    geodesic(v2, v1, v2, t, GEOD_REL);
+		    pos_from_vec(pos, v2);
 		    rbf->rbfa[n].gx = pos[0];
 		    rbf->rbfa[n].gy = pos[1];
 		    ++n;