--- ray/src/util/dctimestep.c	2009/06/19 06:49:42	2.2
+++ ray/src/util/dctimestep.c	2012/10/23 22:24:09	2.22
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: dctimestep.c,v 2.2 2009/06/19 06:49:42 greg Exp $";
+static const char RCSid[] = "$Id: dctimestep.c,v 2.22 2012/10/23 22:24:09 greg Exp $";
 #endif
 /*
  * Compute time-step result using Daylight Coefficient method.
@@ -10,9 +10,11 @@ static const char RCSid[] = "$Id: dctimestep.c,v 2.2 2
 #include <ctype.h>
 #include "standard.h"
 #include "platform.h"
+#include "paths.h"
 #include "color.h"
 #include "resolu.h"
 #include "bsdf.h"
+#include "bsdf_m.h"
 
 char	*progname;			/* global argv[0] */
 
@@ -38,7 +40,7 @@ cm_alloc(int nrows, int ncols)
 	CMATRIX	*cm;
 
 	if ((nrows <= 0) | (ncols <= 0))
-		return(NULL);
+		error(USER, "attempt to create empty matrix");
 	cm = (CMATRIX *)malloc(sizeof(CMATRIX) +
 				3*sizeof(COLORV)*(nrows*ncols - 1));
 	if (cm == NULL)
@@ -108,6 +110,8 @@ cm_load(const char *fname, int nrows, int ncols, int d
 	CMATRIX	*cm;
 	FILE	*fp = stdin;
 
+	if (ncols <= 0)
+		error(USER, "Non-positive number of columns");
 	if (fname == NULL)
 		fname = "<stdin>";
 	else if ((fp = fopen(fname, "r")) == NULL) {
@@ -160,12 +164,12 @@ cm_load(const char *fname, int nrows, int ncols, int d
 		int	maxrow = (nrows > 0 ? nrows : 32000);
 		int	r, c;
 		for (r = 0; r < maxrow; r++) {
-		    if (r >= cm->nrows)		/* need more space? */
+		    if (r >= cm->nrows)			/* need more space? */
 			cm = cm_resize(cm, 2*cm->nrows);
 		    for (c = 0; c < ncols; c++) {
 		        COLORV	*cv = cm_lval(cm,r,c);
 			if (fscanf(fp, COLSPEC, cv, cv+1, cv+2) != 3)
-				if ((nrows <= 0) & (r > 0) & (c == 0)) {
+				if ((nrows <= 0) & (r > 0) & !c) {
 					cm = cm_resize(cm, maxrow=r);
 					break;
 				} else
@@ -193,7 +197,7 @@ cm_load(const char *fname, int nrows, int ncols, int d
 					if (nread == cm->nrows*cm->ncols)
 							/* need more space? */
 						cm = cm_resize(cm, 2*cm->nrows);
-					else if (nread % cm->ncols == 0)
+					else if (nread && !(nread % cm->ncols))
 							/* seem to be  done */
 						cm = cm_resize(cm, nread/cm->ncols);
 					else		/* ended mid-row */
@@ -248,8 +252,29 @@ not_handled:
 	return(NULL);	/* gratis return */
 }
 
-/* Multiply two matrices (or a matrix and a vector) and allocate the result*/
+/* Scale a matrix by a single value */
 static CMATRIX *
+cm_scale(const CMATRIX *cm1, const COLOR sca)
+{
+	CMATRIX	*cmr;
+	int	dr, dc;
+
+	cmr = cm_alloc(cm1->nrows, cm1->ncols);
+	if (cmr == NULL)
+		return(NULL);
+	for (dr = 0; dr < cmr->nrows; dr++)
+	    for (dc = 0; dc < cmr->ncols; dc++) {
+	        const COLORV	*sp = cm_lval(cm1,dr,dc);
+		COLORV		*dp = cm_lval(cmr,dr,dc);
+		dp[0] = sp[0] * sca[0];
+		dp[1] = sp[1] * sca[1];
+		dp[2] = sp[2] * sca[2];
+	    }
+	return(cmr);
+}
+
+/* Multiply two matrices (or a matrix and a vector) and allocate the result */
+static CMATRIX *
 cm_multiply(const CMATRIX *cm1, const CMATRIX *cm2)
 {
 	CMATRIX	*cmr;
@@ -289,23 +314,154 @@ cm_print(const CMATRIX *cm, FILE *fp)
 	}
 }
 
-/* convert a BSDF to our matrix representation */
+/* Convert a BSDF to our matrix representation */
 static CMATRIX *
-cm_bsdf(const struct BSDF_data *bsdf)
+cm_bsdf(const COLOR bsdfLamb, const COLOR specCol, const SDMat *bsdf)
 {
 	CMATRIX	*cm = cm_alloc(bsdf->nout, bsdf->ninc);
-	COLORV	*mp = cm->cmem;
+	int	nbadohm = 0;
+	int	nneg = 0;
 	int	r, c;
-	
-	for (r = 0; r < cm->nrows; r++)
-		for (c = 0; c < cm->ncols; c++, mp += 3)
-			mp[0] = mp[1] = mp[2] = BSDF_value(bsdf,c,r);
+					/* loop over incident angles */
+	for (c = 0; c < cm->ncols; c++) {
+		const double	dom = mBSDF_incohm(bsdf,c);
+					/* projected solid angle */
+		nbadohm += (dom <= 0);
+
+		for (r = 0; r < cm->nrows; r++) {
+			float	f = mBSDF_value(bsdf,c,r);
+			COLORV	*mp = cm_lval(cm,r,c);
+					/* check BSDF value */
+			if ((f <= 0) | (dom <= 0)) {
+				nneg += (f < -FTINY);
+				f = .0f;
+			}
+			copycolor(mp, specCol);
+			scalecolor(mp, f);
+			addcolor(mp, bsdfLamb);
+			scalecolor(mp, dom);
+		}
+	}
+	if (nneg | nbadohm) {
+		sprintf(errmsg,
+		    "BTDF has %d negatives and %d bad incoming solid angles",
+				nneg, nbadohm);
+		error(WARNING, errmsg);
+	}
 	return(cm);
 }
 
+/* Convert between input and output indices for reciprocity */
+static int
+recip_out_from_in(const SDMat *bsdf, int in_recip)
+{
+	FVECT	v;
+
+	if (!mBSDF_incvec(v, bsdf, in_recip+.5))
+		return(in_recip);		/* XXX should be error! */
+	v[2] = -v[2];
+	return(mBSDF_outndx(bsdf, v));
+}
+
+/* Convert between output and input indices for reciprocity */
+static int
+recip_in_from_out(const SDMat *bsdf, int out_recip)
+{
+	FVECT	v;
+
+	if (!mBSDF_outvec(v, bsdf, out_recip+.5))
+		return(out_recip);		/* XXX should be error! */
+	v[2] = -v[2];
+	return(mBSDF_incndx(bsdf, v));
+}
+
+/* Convert a BSDF to our matrix representation, applying reciprocity */
+static CMATRIX *
+cm_bsdf_recip(const COLOR bsdfLamb, const COLOR specCol, const SDMat *bsdf)
+{
+	CMATRIX	*cm = cm_alloc(bsdf->ninc, bsdf->nout);
+	int	nbadohm = 0;
+	int	nneg = 0;
+	int	r, c;
+					/* loop over incident angles */
+	for (c = 0; c < cm->ncols; c++) {
+		const int	ro = recip_out_from_in(bsdf,c);
+		const double	dom = mBSDF_outohm(bsdf,ro);
+					/* projected solid angle */
+		nbadohm += (dom <= 0);
+
+		for (r = 0; r < cm->nrows; r++) {
+			const int	ri = recip_in_from_out(bsdf,r);
+			float		f = mBSDF_value(bsdf,ri,ro);
+			COLORV		*mp = cm_lval(cm,r,c);
+					/* check BSDF value */
+			if ((f <= 0) | (dom <= 0)) {
+				nneg += (f < -FTINY);
+				f = .0f;
+			}
+			copycolor(mp, specCol);
+			scalecolor(mp, f);
+			addcolor(mp, bsdfLamb);
+			scalecolor(mp, dom);
+		}
+	}
+	if (nneg | nbadohm) {
+		sprintf(errmsg,
+		    "BTDF has %d negatives and %d bad incoming solid angles",
+				nneg, nbadohm);
+		error(WARNING, errmsg);
+	}
+	return(cm);
+}
+
+/* Load and convert a matrix BSDF from the given XML file */
+static CMATRIX *
+cm_loadBSDF(char *fname, COLOR cLamb)
+{
+	CMATRIX		*Tmat;
+	char		*fpath;
+	int		recip;
+	SDError		ec;
+	SDData		myBSDF;
+	SDSpectralDF	*tdf;
+	COLOR		bsdfLamb, specCol;
+					/* find path to BSDF file */
+	fpath = getpath(fname, getrlibpath(), R_OK);
+	if (fpath == NULL) {
+		sprintf(errmsg, "cannot find BSDF file '%s'", fname);
+		error(USER, errmsg);
+	}
+	SDclearBSDF(&myBSDF, fname);	/* load XML and check type */
+	ec = SDloadFile(&myBSDF, fpath);
+	if (ec)
+		error(USER, transSDError(ec));
+	ccy2rgb(&myBSDF.tLamb.spec, myBSDF.tLamb.cieY/PI, bsdfLamb);
+	recip = (myBSDF.tf == NULL);
+	tdf = recip ? myBSDF.tb : myBSDF.tf;
+	if (tdf == NULL) {		/* no non-Lambertian transmission? */
+		if (cLamb != NULL)
+			copycolor(cLamb, bsdfLamb);
+		SDfreeBSDF(&myBSDF);
+		return(NULL);
+	}
+	if (tdf->ncomp != 1 || tdf->comp[0].func != &SDhandleMtx) {
+		sprintf(errmsg, "unsupported BSDF '%s'", fpath);
+		error(USER, errmsg);
+	}
+					/* convert BTDF to matrix */
+	ccy2rgb(&tdf->comp[0].cspec[0], 1., specCol);
+	Tmat = recip ? cm_bsdf_recip(bsdfLamb, specCol, (SDMat *)tdf->comp[0].dist)
+			: cm_bsdf(bsdfLamb, specCol, (SDMat *)tdf->comp[0].dist);
+	if (cLamb != NULL)		/* Lambertian is included */
+		setcolor(cLamb, .0, .0, .0);
+					/* free BSDF and return */
+	SDfreeBSDF(&myBSDF);
+	return(Tmat);
+}
+
 /* Sum together a set of images and write result to stdout */
 static int
-sum_images(const char *fspec, const CMATRIX *cv)
+sum_images(const char *fspec, const CMATRIX *cv, FILE *fout)
 {
 	int	myDT = DTfromHeader;
 	CMATRIX	*pmat;
@@ -321,6 +477,10 @@ sum_images(const char *fspec, const CMATRIX *cv)
 		FILE		*fp;
 		int		dt, xr, yr;
 		COLORV		*psp;
+							/* check for zero */
+		if ((scv[RED] == 0) & (scv[GRN] == 0) & (scv[BLU] == 0) &&
+				(myDT != DTfromHeader) | (i < cv->nrows-1))
+			continue;
 							/* open next picture */
 		sprintf(fname, fspec, i);
 		if ((fp = fopen(fname, "r")) == NULL) {
@@ -343,10 +503,10 @@ sum_images(const char *fspec, const CMATRIX *cv)
 			pmat = cm_alloc(myYR, myXR);
 			memset(pmat->cmem, 0, sizeof(COLOR)*myXR*myYR);
 							/* finish header */
-			fputformat(myDT==DTrgbe ? COLRFMT : CIEFMT, stdout);
-			fputc('\n', stdout);
-			fprtresolu(myXR, myYR, stdout);
-			fflush(stdout);
+			fputformat(myDT==DTrgbe ? COLRFMT : CIEFMT, fout);
+			fputc('\n', fout);
+			fprtresolu(myXR, myYR, fout);
+			fflush(fout);
 		} else if ((dt != myDT) | (xr != myXR) | (yr != myYR)) {
 			sprintf(errmsg, "picture '%s' format/size mismatch",
 					fname);
@@ -371,63 +531,78 @@ sum_images(const char *fspec, const CMATRIX *cv)
 	free(scanline);
 							/* write scanlines */
 	for (y = 0; y < myYR; y++)
-		if (fwritescan((COLOR *)cm_lval(pmat, y, 0), myXR, stdout) < 0)
+		if (fwritescan((COLOR *)cm_lval(pmat, y, 0), myXR, fout) < 0)
 			return(0);
 	cm_free(pmat);					/* all done */
-	return(fflush(stdout) == 0);
+	return(fflush(fout) == 0);
 }
 
-/* check to see if a string contains a %d specification */
-int
-hasDecimalSpec(const char *s)
+/* check to see if a string contains a %d or %o specification */
+static int
+hasNumberFormat(const char *s)
 {
-	while (*s && *s != '%')
-		s++;
-	if (!*s)
-		return(0);
-	do
-		++s;
-	while (isdigit(*s));
-
-	return(*s == 'd');
+	while (*s) {
+		while (*s != '%')
+			if (!*s++)
+				return(0);
+		if (*++s == '%') {		/* ignore "%%" */
+			++s;
+			continue;
+		}
+		while (isdigit(*s))		/* field length */
+			++s;
+						/* field we'll use? */
+		if ((*s == 'd') | (*s == 'i') | (*s == 'o') |
+					(*s == 'x') | (*s == 'X'))
+			return(1);
+	}
+	return(0);				/* didn't find one */
 }
 
 int
 main(int argc, char *argv[])
 {
-	CMATRIX			*tvec, *Dmat, *Tmat, *ivec, *cvec;
-	struct BSDF_data	*btdf;
+	CMATRIX			*cvec;		/* component vector result */
 
 	progname = argv[0];
 
-	if ((argc < 4) | (argc > 5)) {
-		fprintf(stderr, "Usage: %s Vspec Tbsdf.xml Dmat.dat [tregvec]\n",
-				progname);
+	if ((argc < 2) | (argc > 5)) {
+		fprintf(stderr, "Usage: %s DCspec [tregvec]\n", progname);
+		fprintf(stderr, "   or: %s Vspec Tbsdf.xml Dmat.dat [tregvec]\n",
+					progname);
 		return(1);
 	}
-	tvec = cm_load(argv[4], 0, 1, DTascii);	/* argv[4]==NULL iff argc==4 */
-	Dmat = cm_load(argv[3], 0, tvec->nrows, DTfromHeader);
-	btdf = load_BSDF(argv[2]);
-	if (btdf == NULL)
-		return(1);
-	if (btdf->ninc != Dmat->nrows) {
-		sprintf(errmsg, "Incoming BTDF dir (%d) mismatch to D (%d)",
-				btdf->ninc, Dmat->nrows);
-		error(USER, errmsg);
-	}
+
+	if (argc > 3) {				/* VTDs expression */
+		CMATRIX	*svec, *Dmat, *Tmat, *ivec;
+		COLOR	tLamb;
+						/* get sky vector */
+		svec = cm_load(argv[4], 0, 1, DTascii);
+						/* load BSDF */
+		Tmat = cm_loadBSDF(argv[2], tLamb);
+						/* load Daylight matrix */
+		Dmat = cm_load(argv[3], Tmat==NULL ? 0 : Tmat->ncols,
+					svec->nrows, DTfromHeader);
 						/* multiply vector through */
-	ivec = cm_multiply(Dmat, tvec);
-	cm_free(Dmat); cm_free(tvec);
-	Tmat = cm_bsdf(btdf);			/* convert BTDF to matrix */
-	free_BSDF(btdf);
-	cvec = cm_multiply(Tmat, ivec);		/* cvec = component vector */
-	cm_free(Tmat); cm_free(ivec);
-	if (hasDecimalSpec(argv[1])) {		/* generating image */
+		ivec = cm_multiply(Dmat, svec);
+		cm_free(Dmat); cm_free(svec);
+		if (Tmat == NULL) {		/* diffuse only */
+			cvec = cm_scale(ivec, tLamb);
+		} else {			/* else apply BTDF matrix */
+			cvec = cm_multiply(Tmat, ivec);
+			cm_free(Tmat); 
+		}
+		cm_free(ivec);
+	} else {				/* else just use sky vector */
+		cvec = cm_load(argv[2], 0, 1, DTascii);
+	}
+
+	if (hasNumberFormat(argv[1])) {		/* generating image */
 		SET_FILE_BINARY(stdout);
 		newheader("RADIANCE", stdout);
 		printargs(argc, argv, stdout);
 		fputnow(stdout);
-		if (!sum_images(argv[1], cvec))
+		if (!sum_images(argv[1], cvec, stdout))
 			return(1);
 	} else {				/* generating vector */
 		CMATRIX	*Vmat = cm_load(argv[1], 0, cvec->nrows, DTfromHeader);