--- ray/src/util/dctimestep.c	2009/06/20 04:37:43	2.6
+++ ray/src/util/dctimestep.c	2011/04/08 18:13:48	2.15
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: dctimestep.c,v 2.6 2009/06/20 04:37:43 greg Exp $";
+static const char RCSid[] = "$Id: dctimestep.c,v 2.15 2011/04/08 18:13:48 greg Exp $";
 #endif
 /*
  * Compute time-step result using Daylight Coefficient method.
@@ -10,9 +10,11 @@ static const char RCSid[] = "$Id: dctimestep.c,v 2.6 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) {
@@ -289,36 +293,72 @@ 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;
+	CMATRIX	*cm;
 	int	nbadohm = 0;
 	int	nneg = 0;
+	FVECT	v;
+	float	dom;
+	int	doforward;
 	int	r, c;
-	
-	for (r = 0; r < cm->nrows; r++)
-		for (c = 0; c < cm->ncols; c++, mp += 3) {
-			float	f = BSDF_value(bsdf,c,r);
-			float	dom = getBSDF_incohm(bsdf,c);
-			FVECT	v;
+
+	mBSDF_incvec(v, bsdf, .5);	/* check BTDF orientation */
+
+	if (v[2] < 0) {			/* incident from outside */
+		cm = cm_alloc(bsdf->nout, bsdf->ninc);
+		for (c = 0; c < cm->ncols; c++) {
+			dom = mBSDF_incohm(bsdf,c);
 			
-			if (f <= .0) {
-				nneg += (f < -FTINY);
-				continue;
+			nbadohm += (dom <= 0);
+
+			if (!mBSDF_incvec(v,bsdf,c+.5) || v[2] > 0)
+				error(USER, "illegal incoming BTDF direction");
+			dom *= -v[2];
+
+			for (r = 0; r < cm->nrows; r++) {
+				float	f = mBSDF_value(bsdf,c,r);
+				COLORV	*mp = cm_lval(cm,r,c);
+
+				if ((f <= 0) | (dom <= 0)) {
+					nneg += (f < -FTINY);
+					f = .0f;
+				}
+				copycolor(mp, specCol);
+				f *= dom;
+				scalecolor(mp, f);
+				addcolor(mp, bsdfLamb);
 			}
-			if (dom <= .0) {
-				nbadohm++;
-				continue;
+		}
+	} else {			/* rely on reciprocity */
+		cm = cm_alloc(bsdf->ninc, bsdf->nout);
+		for (c = 0; c < cm->ncols; c++) {
+			dom = mBSDF_outohm(bsdf,c);
+			
+			nbadohm += (dom <= 0);
+
+			if (!mBSDF_outvec(v,bsdf,c+.5) || v[2] > 0)
+				error(USER, "illegal outgoing BTDF direction");
+			dom *= -v[2];
+
+			for (r = 0; r < cm->nrows; r++) {
+				float	f = mBSDF_value(bsdf,r,c);
+				COLORV	*mp = cm_lval(cm,r,c);
+
+				if ((f <= 0) | (dom <= 0)) {
+					nneg += (f < -FTINY);
+					f = .0f;
+				}
+				copycolor(mp, specCol);
+				f *= dom;
+				scalecolor(mp, f);
+				addcolor(mp, bsdfLamb);
 			}
-			if (!getBSDF_incvec(v,bsdf,c) || v[2] > FTINY)
-				error(USER, "illegal incoming BTDF direction");
-				
-			mp[0] = mp[1] = mp[2] = f * dom * -v[2];
 		}
-	if (nneg || nbadohm) {
+	}
+	if (nneg | nbadohm) {
 		sprintf(errmsg,
 		    "BTDF has %d negatives and %d bad incoming solid angles",
 				nneg, nbadohm);
@@ -327,9 +367,43 @@ cm_bsdf(const struct BSDF_data *bsdf)
 	return(cm);
 }
 
+/* Load and convert a matrix BSDF from the given XML file */
+static CMATRIX *
+cm_loadBSDF(char *fname)
+{
+	CMATRIX	*Tmat;
+	char	*fpath;
+	SDError	ec;
+	SDData	myBSDF;
+	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);
+	}
+	SDclipName(myBSDF.name, fname);
+					/* load XML and check type */
+	ec = SDloadFile(&myBSDF, fpath);
+	if (ec)
+		error(USER, transSDError(ec));
+	if (myBSDF.tf == NULL || myBSDF.tf->ncomp != 1 ||
+			myBSDF.tf->comp[0].func != &SDhandleMtx) {
+		sprintf(errmsg, "unsupported BSDF '%s'", fpath);
+		error(USER, errmsg);
+	}
+					/* convert BTDF to matrix */
+	ccy2rgb(&myBSDF.tLamb.spec, myBSDF.tLamb.cieY/PI, bsdfLamb);
+	ccy2rgb(&myBSDF.tf->comp[0].cspec[0], 1., specCol);
+	Tmat = cm_bsdf(bsdfLamb, specCol, (SDMat *)myBSDF.tf->comp[0].dist);
+					/* 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;
@@ -345,6 +419,9 @@ 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))
+			continue;
 							/* open next picture */
 		sprintf(fname, fspec, i);
 		if ((fp = fopen(fname, "r")) == NULL) {
@@ -367,10 +444,10 @@ 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);
@@ -395,15 +472,15 @@ 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++;
@@ -413,43 +490,47 @@ hasDecimalSpec(const char *s)
 		++s;
 	while (isdigit(*s));
 
-	return(*s == 'd');
+	return((*s == 'd') | (*s == 'i') | (*s == 'o') |
+			(*s == 'x') | (*s == 'X'));
 }
 
 int
 main(int argc, char *argv[])
 {
-	CMATRIX			*tvec, *Dmat, *Tmat, *ivec, *cvec;
-	struct BSDF_data	*btdf;
+	CMATRIX			*cvec;
 
 	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);
 	}
-						/* load Tregenza vector */
-	tvec = cm_load(argv[4], 0, 1, DTascii);	/* argv[4]==NULL iff argc==4 */
-						/* load BTDF */
-	btdf = load_BSDF(argv[2]);
-	if (btdf == NULL)
-		return(1);
+
+	if (argc > 3) {				/* VTDs expression */
+		CMATRIX	*svec, *Dmat, *Tmat, *ivec;
+						/* get sky vector */
+		svec = cm_load(argv[4], 0, 1, DTascii);
+						/* load BSDF */
+		Tmat = cm_loadBSDF(argv[2]);
 						/* load Daylight matrix */
-	Dmat = cm_load(argv[3], btdf->ninc, tvec->nrows, DTfromHeader);
+		Dmat = cm_load(argv[3], 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);
+		cvec = cm_multiply(Tmat, ivec);	/* cvec = component vector */
+		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);