--- ray/src/util/rmatrix.c	2023/11/27 22:04:45	2.61
+++ ray/src/util/rmatrix.c	2023/11/28 21:28:11	2.66
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: rmatrix.c,v 2.61 2023/11/27 22:04:45 greg Exp $";
+static const char RCSid[] = "$Id: rmatrix.c,v 2.66 2023/11/28 21:28:11 greg Exp $";
 #endif
 /*
  * General matrix operations.
@@ -172,153 +172,207 @@ get_dminfo(char *s, void *p)
 }
 
 static int
-rmx_load_ascii(RMATRIX *rm, FILE *fp)
+rmx_load_ascii(double *drp, const RMATRIX *rm, FILE *fp)
 {
-	int	i, j, k;
+	int	j, k;
 
-	if (!rmx_prepare(rm))
-		return(0);
-	for (i = 0; i < rm->nrows; i++)
-	    for (j = 0; j < rm->ncols; j++) {
-	    	double	*dp = rmx_lval(rm,i,j);
-	        for (k = 0; k < rm->ncomp; k++)
-		    if (fscanf(fp, "%lf", &dp[k]) != 1)
-			return(0);
-	    }
+	for (j = 0; j < rm->ncols; j++)
+	        for (k = rm->ncomp; k-- > 0; )
+			if (fscanf(fp, "%lf", drp++) != 1)
+				return(0);
 	return(1);
 }
 
 static int
-rmx_load_float(RMATRIX *rm, FILE *fp)
+rmx_load_float(double *drp, const RMATRIX *rm, FILE *fp)
 {
-	int	i, j, k;
+	int	j, k;
 	float	val[100];
 
 	if (rm->ncomp > 100) {
 		fputs("Unsupported # components in rmx_load_float()\n", stderr);
 		exit(1);
 	}
-	if (!rmx_prepare(rm))
-		return(0);
-	for (i = 0; i < rm->nrows; i++)
-	    for (j = 0; j < rm->ncols; j++) {
-	    	double	*dp = rmx_lval(rm,i,j);
+	for (j = 0; j < rm->ncols; j++) {
 		if (getbinary(val, sizeof(val[0]), rm->ncomp, fp) != rm->ncomp)
-		    return(0);
+			return(0);
 		if (rm->swapin)
-		    swap32((char *)val, rm->ncomp);
-	        for (k = rm->ncomp; k--; )
-		     dp[k] = val[k];
-	    }
+			swap32((char *)val, rm->ncomp);
+	        for (k = 0; k < rm->ncomp; k++)
+			*drp++ = val[k];
+	}
 	return(1);
 }
 
 static int
-rmx_load_double(RMATRIX *rm, FILE *fp)
+rmx_load_double(double *drp, const RMATRIX *rm, FILE *fp)
 {
-	int	i;
-#ifdef MAP_FILE
-	long	pos;		/* map memory for file > 1MB if possible */
-	if (!rm->swapin && array_size(rm) >= 1L<<20 &&
-			(pos = ftell(fp)) >= 0 && !(pos % sizeof(double))) {
-		rm->mapped = mmap(NULL, array_size(rm)+pos, PROT_READ|PROT_WRITE,
-					MAP_PRIVATE, fileno(fp), 0);
-		if (rm->mapped != MAP_FAILED) {
-			rm->mtx = (double *)rm->mapped + pos/sizeof(double);
-			return(1);
-		}		/* else fall back on reading into memory */
-		rm->mapped = NULL;
-	}
-#endif
-	if (!rmx_prepare(rm))
+	if (getbinary(drp, sizeof(*drp)*rm->ncomp, rm->ncols, fp) != rm->ncols)
 		return(0);
-	for (i = 0; i < rm->nrows; i++) {
-		if (getbinary(rmx_lval(rm,i,0), sizeof(double)*rm->ncomp,
-					rm->ncols, fp) != rm->ncols)
-			return(0);
-		if (rm->swapin)
-			swap64((char *)rmx_lval(rm,i,0), rm->ncols*rm->ncomp);
-	}
+	if (rm->swapin)
+		swap64((char *)drp, rm->ncols*rm->ncomp);
 	return(1);
 }
 
 static int
-rmx_load_rgbe(RMATRIX *rm, FILE *fp)
+rmx_load_rgbe(double *drp, const RMATRIX *rm, FILE *fp)
 {
-	COLOR	*scan = (COLOR *)malloc(sizeof(COLOR)*rm->ncols);
-	int	i, j;
+	COLR	*scan;
+	COLOR	col;
+	int	j;
 
+	if (rm->ncomp != 3)
+		return(0);
+	scan = (COLR *)tempbuffer(sizeof(COLR)*rm->ncols);
 	if (!scan)
 		return(0);
-	if (!rmx_prepare(rm)) {
-		free(scan);
+	if (freadcolrs(scan, rm->ncols, fp) < 0)
 		return(0);
+	for (j = 0; j < rm->ncols; j++) {
+		colr_color(col, scan[j]);
+		*drp++ = colval(col,RED);
+		*drp++ = colval(col,GRN);
+		*drp++ = colval(col,BLU);
 	}
-	for (i = 0; i < rm->nrows; i++) {
-	    double	*dp = rmx_lval(rm,i,0);
-	    if (freadscan(scan, rm->ncols, fp) < 0) {
-		free(scan);
-		return(0);
-	    }
-	    for (j = 0; j < rm->ncols; j++, dp += 3) {
-	        dp[0] = colval(scan[j],RED);
-	        dp[1] = colval(scan[j],GRN);
-	        dp[2] = colval(scan[j],BLU);
-	    }
-	}
-	free(scan);
 	return(1);
 }
 
 static int
-rmx_load_spec(RMATRIX *rm, FILE *fp)
+rmx_load_spec(double *drp, const RMATRIX *rm, FILE *fp)
 {
 	uby8	*scan;
 	SCOLOR	scol;
-	int	i, j, k;
+	int	j, k;
 
-	if (rm->ncomp < 3)
+	if ((rm->ncomp < 3) | (rm->ncomp > MAXCSAMP))
 		return(0);
-	scan = (uby8 *)malloc((rm->ncomp+1)*rm->ncols);
+	scan = (uby8 *)tempbuffer((rm->ncomp+1)*rm->ncols);
 	if (!scan)
 		return(0);
-	if (!rmx_prepare(rm)) {
-		free(scan);
+	if (freadscolrs(scan, rm->ncomp, rm->ncols, fp) < 0)
 		return(0);
+	for (j = 0; j < rm->ncols; j++) {
+		scolr2scolor(scol, scan+j*(rm->ncomp+1), rm->ncomp);
+		for (k = 0; k < rm->ncomp; k++)
+			*drp++ = scol[k];
 	}
-	for (i = 0; i < rm->nrows; i++) {
-	    double	*dp = rmx_lval(rm,i,0);
-	    if (freadscolrs(scan, rm->ncomp, rm->ncols, fp) < 0) {
-		free(scan);
+	return(1);
+}
+
+/* Read matrix header from input stream (cannot be XML) */
+int
+rmx_load_header(RMATRIX *rm, FILE *fp)
+{
+	if (!rm | !fp)
 		return(0);
-	    }
-	    for (j = 0; j < rm->ncols; j++) {
-	    	scolr2scolor(scol, scan+j*(rm->ncomp+1), rm->ncomp);
-	    	for (k = 0; k < rm->ncomp; k++)
-	    		*dp++ = scol[k];
-	    }
+	if (rm->info) {				/* clear state */
+		free(rm->info);
+		rm->info = NULL;
 	}
-	free(scan);
+	if (rm->mtx) {				/* ...and data */
+#ifdef MAP_FILE
+		if (rm->mapped) {
+			munmap(rm->mapped, mapped_size(rm));
+			rm->mapped = NULL;
+		} else
+#endif
+			free(rm->mtx);
+		rm->mtx = NULL;
+	}
+	if (rm->nrows | rm->ncols | !rm->dtype) {
+		rm->nrows = rm->ncols = 0;
+		rm->ncomp = 3;
+		setcolor(rm->cexp, 1.f, 1.f, 1.f);
+		memcpy(rm->wlpart, WLPART, sizeof(rm->wlpart));
+		rm->swapin = 0;
+	}
+	SET_FILE_BINARY(fp);
+	rm->dtype = DTascii;			/* assumed w/o FORMAT */
+	if (getheader(fp, get_dminfo, rm) < 0) {
+		fputs("Unrecognized matrix format\n", stderr);
+		return(0);
+	}
+						/* resolution string? */
+	if ((rm->nrows <= 0) | (rm->ncols <= 0)) {
+		if (!fscnresolu(&rm->ncols, &rm->nrows, fp))
+			return(0);
+		if ((rm->dtype == DTrgbe) | (rm->dtype == DTxyze) &&
+				rm->ncomp != 3)
+			return(0);
+	}
 	return(1);
 }
 
+/* Load next row as double (cannot be XML) */
+int
+rmx_load_row(double *drp, const RMATRIX *rm, FILE *fp)
+{
+	switch (rm->dtype) {
+	case DTascii:
+		return(rmx_load_ascii(drp, rm, fp));
+	case DTfloat:
+		return(rmx_load_float(drp, rm, fp));
+	case DTdouble:
+		return(rmx_load_double(drp, rm, fp));
+	case DTrgbe:
+	case DTxyze:
+		return(rmx_load_rgbe(drp, rm, fp));
+	case DTspec:
+		return(rmx_load_spec(drp, rm, fp));
+	default:
+		fputs("Unsupported data type in rmx_load_row()\n", stderr);
+	}
+	return(0);
+}
+
+/* Allocate & load post-header data from stream given type set in rm->dtype */
+int
+rmx_load_data(RMATRIX *rm, FILE *fp)
+{
+	int	i;
+#ifdef MAP_FILE
+	long	pos;		/* map memory for file > 1MB if possible */
+	if ((rm->dtype == DTdouble) & !rm->swapin && array_size(rm) >= 1L<<20 &&
+			(pos = ftell(fp)) >= 0 && !(pos % sizeof(double))) {
+		rm->mapped = mmap(NULL, array_size(rm)+pos, PROT_READ|PROT_WRITE,
+					MAP_PRIVATE, fileno(fp), 0);
+		if (rm->mapped != MAP_FAILED) {
+			rm->mtx = (double *)rm->mapped + pos/sizeof(double);
+			return(1);
+		}		/* else fall back on reading into memory */
+		rm->mapped = NULL;
+	}
+#endif
+	if (!rmx_prepare(rm)) {	/* need in-core matrix array */
+		fprintf(stderr, "Cannot allocate %g MByte matrix array\n",
+				(1./(1L<<20))*(double)array_size(rm));
+		return(0);
+	}
+	if (rm->dtype == DTascii)
+		SET_FILE_TEXT(fp);
+	for (i = 0; i < rm->nrows; i++)
+		if (!rmx_load_row(rmx_lval(rm,i,0), rm, fp))
+			return(0);
+	return(1);
+}
+
 /* Load matrix from supported file type */
 RMATRIX *
 rmx_load(const char *inspec, RMPref rmp)
 {
 	FILE		*fp;
 	RMATRIX		*dnew;
+	int		ok;
 
 	if (!inspec)
 		inspec = stdin_name;
 	else if (!*inspec)
 		return(NULL);
-	if (inspec == stdin_name) {		/* reading from stdin? */
+	if (inspec == stdin_name)		/* reading from stdin? */
 		fp = stdin;
-	} else if (inspec[0] == '!') {
-		if (!(fp = popen(inspec+1, "r")))
-			return(NULL);
-	} else {
+	else if (inspec[0] == '!')
+		fp = popen(inspec+1, "r");
+	else {
 		const char	*sp = inspec;	/* check suffix */
 		while (*sp)
 			++sp;
@@ -332,66 +386,26 @@ rmx_load(const char *inspec, RMPref rmp)
 			dnew = rmx_from_cmatrix(cm);
 			cm_free(cm);
 			dnew->dtype = DTascii;
-			return(dnew);
-		}
-						/* else open it ourselves */
-		if (!(fp = fopen(inspec, "r")))
-			return(NULL);
+			return(dnew);		/* return here */
+		}				/* else open it ourselves */
+		fp = fopen(inspec, "r");
 	}
-	SET_FILE_BINARY(fp);
+	if (!fp)
+		return(NULL);
 #ifdef getc_unlocked
 	flockfile(fp);
 #endif
-	if (!(dnew = rmx_new(0,0,3))) {
-		fclose(fp);
+						/* load header info */
+	if (!rmx_load_header(dnew = rmx_new(0,0,3), fp)) {
+		fprintf(stderr, "Bad header in: %s\n", inspec);
+		if (inspec[0] == '!') pclose(fp);
+		else fclose(fp);
+		rmx_free(dnew);
 		return(NULL);
 	}
-	dnew->dtype = DTascii;			/* assumed w/o FORMAT */
-	if (getheader(fp, get_dminfo, dnew) < 0) {
-		fclose(fp);
-		return(NULL);
-	}
-	if ((dnew->nrows <= 0) | (dnew->ncols <= 0)) {
-		if (!fscnresolu(&dnew->ncols, &dnew->nrows, fp)) {
-			fclose(fp);
-			return(NULL);
-		}
-		if ((dnew->dtype == DTrgbe) | (dnew->dtype == DTxyze) &&
-				dnew->ncomp != 3) {
-			fclose(fp);
-			return(NULL);
-		}
-	}
-	switch (dnew->dtype) {
-	case DTascii:
-		SET_FILE_TEXT(fp);
-		if (!rmx_load_ascii(dnew, fp))
-			goto loaderr;
-		dnew->dtype = DTascii;		/* should leave double? */
-		break;
-	case DTfloat:
-		if (!rmx_load_float(dnew, fp))
-			goto loaderr;
-		dnew->dtype = DTfloat;
-		break;
-	case DTdouble:
-		if (!rmx_load_double(dnew, fp))
-			goto loaderr;
-		dnew->dtype = DTdouble;
-		break;
-	case DTrgbe:
-	case DTxyze:
-		if (!rmx_load_rgbe(dnew, fp))
-			goto loaderr;
-		break;
-	case DTspec:
-		if (!rmx_load_spec(dnew, fp))
-			goto loaderr;
-		break;
-	default:
-		goto loaderr;
-	}
-	if (fp != stdin) {
+	ok = rmx_load_data(dnew, fp);		/* allocate & load data */
+
+	if (fp != stdin) {			/* close input stream */
 		if (inspec[0] == '!')
 			pclose(fp);
 		else
@@ -401,6 +415,11 @@ rmx_load(const char *inspec, RMPref rmp)
 	else
 		funlockfile(fp);
 #endif
+	if (!ok) {				/* load failure? */
+		fprintf(stderr, "Error loading data from: %s\n", inspec);
+		rmx_free(dnew);
+		return(NULL);
+	}
 						/* undo exposure? */
 	if ((dnew->cexp[0] != 1.f) |
 			(dnew->cexp[1] != 1.f) | (dnew->cexp[2] != 1.f)) {
@@ -409,21 +428,18 @@ rmx_load(const char *inspec, RMPref rmp)
 		cmlt[0] = 1./dnew->cexp[0];
 		cmlt[1] = 1./dnew->cexp[1];
 		cmlt[2] = 1./dnew->cexp[2];
-		if (dnew->ncomp > MAXCSAMP)
-			goto loaderr;
+		if (dnew->ncomp > MAXCSAMP) {
+			fprintf(stderr, "Excess spectral components in: %s\n",
+					inspec);
+			rmx_free(dnew);
+			return(NULL);
+		}
 		for (i = dnew->ncomp; i-- > 3; )
 			cmlt[i] = cmlt[1];
 		rmx_scale(dnew, cmlt);
 		setcolor(dnew->cexp, 1.f, 1.f, 1.f);
 	}
 	return(dnew);
-loaderr:					/* should report error? */
-	if (inspec[0] == '!')
-		pclose(fp);
-	else
-		fclose(fp);
-	rmx_free(dnew);
-	return(NULL);
 }
 
 static int
@@ -436,7 +452,7 @@ rmx_write_ascii(const RMATRIX *rm, FILE *fp)
 
 	for (i = 0; i < rm->nrows; i++) {
 	    for (j = 0; j < rm->ncols; j++) {
-		const double	*dp = rmx_lval(rm,i,j);
+		const double	*dp = rmx_val(rm,i,j);
 	        for (k = 0; k < rm->ncomp; k++)
 		    fprintf(fp, fmt, dp[k]);
 		fputc('\t', fp);
@@ -458,7 +474,7 @@ rmx_write_float(const RMATRIX *rm, FILE *fp)
 	}
 	for (i = 0; i < rm->nrows; i++)
 	    for (j = 0; j < rm->ncols; j++) {
-	    	const double	*dp = rmx_lval(rm,i,j);
+	    	const double	*dp = rmx_val(rm,i,j);
 	        for (k = rm->ncomp; k--; )
 		    val[k] = (float)dp[k];
 		if (putbinary(val, sizeof(float), rm->ncomp, fp) != rm->ncomp)
@@ -470,13 +486,8 @@ rmx_write_float(const RMATRIX *rm, FILE *fp)
 static int
 rmx_write_double(const RMATRIX *rm, FILE *fp)
 {
-	int	i;
-
-	for (i = 0; i < rm->nrows; i++)
-		if (putbinary(rmx_lval(rm,i,0), sizeof(double)*rm->ncomp,
-					rm->ncols, fp) != rm->ncols)
-			return(0);
-	return(1);
+	return(putbinary(rm->mtx, sizeof(rm->mtx[0])*rm->ncomp,
+			rm->nrows*rm->ncols, fp) == rm->nrows*rm->ncols);
 }
 
 static int
@@ -489,7 +500,7 @@ rmx_write_rgbe(const RMATRIX *rm, FILE *fp)
 		return(0);
 	for (i = 0; i < rm->nrows; i++) {
 	    for (j = rm->ncols; j--; ) {
-	    	const double	*dp = rmx_lval(rm,i,j);
+	    	const double	*dp = rmx_val(rm,i,j);
 	    	if (rm->ncomp == 1)
 	    		setcolr(scan[j], dp[0], dp[0], dp[0]);
 	    	else
@@ -516,7 +527,7 @@ rmx_write_spec(const RMATRIX *rm, FILE *fp)
 		return(0);
 	for (i = 0; i < rm->nrows; i++) {
 	    for (j = rm->ncols; j--; ) {
-	    	const double	*dp = rmx_lval(rm,i,j);
+	    	const double	*dp = rmx_val(rm,i,j);
 	    	for (k = rm->ncomp; k--; )
 	    		scol[k] = dp[k];
 		scolor2scolr(scan+j*(rm->ncomp+1), scol, rm->ncomp);
@@ -558,8 +569,7 @@ rmx_write(const RMATRIX *rm, int dtype, FILE *fp)
 #ifdef getc_unlocked
 	flockfile(fp);
 #endif
-						/* complete header */
-	if (rm->info)
+	if (rm->info)				/* complete header */
 		fputs(rm->info, fp);
 	if (dtype == DTfromHeader)
 		dtype = rm->dtype;
@@ -575,21 +585,21 @@ rmx_write(const RMATRIX *rm, int dtype, FILE *fp)
 	else if (rm->cexp[GRN] != 1.f)
 		fputexpos(rm->cexp[GRN], fp);
 	if ((dtype != DTrgbe) & (dtype != DTxyze)) {
-		if (dtype == DTspec) {
-			if (rm->ncomp < 3)
-				return(0);	/* bad # components */
-			fputwlsplit(rm->wlpart, fp);
-		} else {
+		if (dtype != DTspec) {
 			fprintf(fp, "NROWS=%d\n", rm->nrows);
 			fprintf(fp, "NCOLS=%d\n", rm->ncols);
-		}
+		} else if (rm->ncomp < 3)
+			return(0);		/* bad # components */
 		fputncomp(rm->ncomp, fp);
+		if (dtype == DTspec || (rm->ncomp > 3 &&
+				memcmp(rm->wlpart, WLPART, sizeof(WLPART))))
+			fputwlsplit(rm->wlpart, fp);
 	} else if ((rm->ncomp != 3) & (rm->ncomp != 1))
 		return(0);			/* wrong # components */
 	if ((dtype == DTfloat) | (dtype == DTdouble))
 		fputendian(fp);			/* important to record */
 	fputformat(cm_fmt_id[dtype], fp);
-	fputc('\n', fp);
+	fputc('\n', fp);			/* end of header */
 	switch (dtype) {			/* write data */
 	case DTascii:
 		ok = rmx_write_ascii(rm, fp);
@@ -616,6 +626,7 @@ rmx_write(const RMATRIX *rm, int dtype, FILE *fp)
 #ifdef getc_unlocked
 	funlockfile(fp);
 #endif
+	if (!ok) fputs("Error writing matrix\n", stderr);
 	return(ok);
 }
 
@@ -685,7 +696,7 @@ rmx_transpose(const RMATRIX *rm)
 	memcpy(dnew->wlpart, rm->wlpart, sizeof(dnew->wlpart));
 	for (j = dnew->ncols; j--; )
 	    for (i = dnew->nrows; i--; )
-	    	memcpy(rmx_lval(dnew,i,j), rmx_lval(rm,j,i),
+	    	memcpy(rmx_lval(dnew,i,j), rmx_val(rm,j,i),
 	    			sizeof(double)*dnew->ncomp);
 	return(dnew);
 }
@@ -712,7 +723,7 @@ rmx_multiply(const RMATRIX *m1, const RMATRIX *m2)
 	        for (k = mres->ncomp; k--; ) {
 		    double	d = 0;
 		    for (h = m1->ncols; h--; )
-			d += rmx_lval(m1,i,h)[k] * rmx_lval(m2,h,j)[k];
+			d += rmx_val(m1,i,h)[k] * rmx_val(m2,h,j)[k];
 		    rmx_lval(mres,i,j)[k] = d;
 		}
 	return(mres);
@@ -739,7 +750,7 @@ rmx_elemult(RMATRIX *m1, const RMATRIX *m2, int divide
 		if (divide) {
 		    double	d;
 		    if (m2->ncomp == 1) {
-			d = rmx_lval(m2,i,j)[0];
+			d = rmx_val(m2,i,j)[0];
 			if (d == 0) {
 			    ++zeroDivides;
 			    for (k = m1->ncomp; k--; )
@@ -751,7 +762,7 @@ rmx_elemult(RMATRIX *m1, const RMATRIX *m2, int divide
 			}
 		    } else
 		        for (k = m1->ncomp; k--; ) {
-			    d = rmx_lval(m2,i,j)[k];
+			    d = rmx_val(m2,i,j)[k];
 			    if (d == 0) {
 			        ++zeroDivides;
 				rmx_lval(m1,i,j)[k] = 0;
@@ -760,12 +771,12 @@ rmx_elemult(RMATRIX *m1, const RMATRIX *m2, int divide
 			}
 		} else {
 		    if (m2->ncomp == 1) {
-			const double	d = rmx_lval(m2,i,j)[0];
+			const double	d = rmx_val(m2,i,j)[0];
 		        for (k = m1->ncomp; k--; )
 			    rmx_lval(m1,i,j)[k] *= d;
 		    } else
 		        for (k = m1->ncomp; k--; )
-			    rmx_lval(m1,i,j)[k] *= rmx_lval(m2,i,j)[k];
+			    rmx_lval(m1,i,j)[k] *= rmx_val(m2,i,j)[k];
 		}
 	if (zeroDivides) {
 		rmx_addinfo(m1, "WARNING: zero divide(s) corrupted results\n");
@@ -801,7 +812,7 @@ rmx_sum(RMATRIX *msum, const RMATRIX *madd, const doub
 		rmx_addinfo(msum, rmx_mismatch_warn);
 	for (i = msum->nrows; i--; )
 	    for (j = msum->ncols; j--; ) {
-	    	const double	*da = rmx_lval(madd,i,j);
+	    	const double	*da = rmx_val(madd,i,j);
 	    	double		*ds = rmx_lval(msum,i,j);
 		for (k = msum->ncomp; k--; )
 		     ds[k] += sf[k] * da[k];
@@ -853,7 +864,7 @@ rmx_transform(const RMATRIX *msrc, int n, const double
 	dnew->dtype = msrc->dtype;
 	for (i = dnew->nrows; i--; )
 	    for (j = dnew->ncols; j--; ) {
-		const double	*ds = rmx_lval(msrc,i,j);
+		const double	*ds = rmx_val(msrc,i,j);
 	        for (kd = dnew->ncomp; kd--; ) {
 		    double	d = 0;
 		    for (ks = msrc->ncomp; ks--; )
@@ -902,7 +913,7 @@ cm_from_rmatrix(const RMATRIX *rm)
 		return(NULL);
 	for (i = cnew->nrows; i--; )
 	    for (j = cnew->ncols; j--; ) {
-		const double	*dp = rmx_lval(rm,i,j);
+		const double	*dp = rmx_val(rm,i,j);
 		COLORV		*cv = cm_lval(cnew,i,j);
 		switch (rm->ncomp) {
 		case 3: