--- ray/src/util/rmatrix.c	2023/12/06 17:57:34	2.73
+++ ray/src/util/rmatrix.c	2024/02/29 03:11:13	2.78
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: rmatrix.c,v 2.73 2023/12/06 17:57:34 greg Exp $";
+static const char RCSid[] = "$Id: rmatrix.c,v 2.78 2024/02/29 03:11:13 greg Exp $";
 #endif
 /*
  * General matrix operations.
@@ -393,8 +393,10 @@ rmx_load(const char *inspec, RMPref rmp)
 		}				/* else open it ourselves */
 		fp = fopen(inspec, "r");
 	}
-	if (!fp)
+	if (!fp) {
+		fprintf(stderr, "Cannot open for reading: %s\n", inspec);
 		return(NULL);
+	}
 #ifdef getc_unlocked
 	flockfile(fp);
 #endif
@@ -499,7 +501,7 @@ rmx_write_spec(const double *dp, int nc, int len, FILE
 	if (nc < 3) return(0);
 	scan = (uby8 *)tempbuffer((nc+1)*len);
 	if (!scan) return(0);
-	for (j = len; j--; dp += nc) {
+	for (j = 0; j < len; j++, dp += nc) {
 	    	for (k = nc; k--; )
 	    		scol[k] = dp[k];
 		scolor2scolr(scan+j*(nc+1), scol, nc);
@@ -539,7 +541,9 @@ rmx_write_header(const RMATRIX *rm, int dtype, FILE *f
 		dtype = DTxyze;
 	else if ((dtype == DTxyze) & (rm->dtype == DTrgbe))
 		dtype = DTrgbe;
-	if ((dtype == DTspec) & (rm->ncomp < 3))
+	if ((dtype < DTspec) & (rm->ncomp > 3))
+		dtype = DTspec;
+	else if ((dtype == DTspec) & (rm->ncomp <= 3))
 		return(0);
 
 	if (dtype == DTascii)			/* set file type (WINDOWS) */
@@ -560,8 +564,8 @@ rmx_write_header(const RMATRIX *rm, int dtype, FILE *f
 	}
 	if (dtype >= DTspec) {			/* # components & split? */
 		fputncomp(rm->ncomp, fp);
-		if (dtype == DTspec || (rm->ncomp > 3 &&
-				memcmp(rm->wlpart, WLPART, sizeof(WLPART))))
+		if (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 */
@@ -683,12 +687,16 @@ rmx_transfer_data(RMATRIX *rdst, RMATRIX *rsrc, int do
 		rsrc->info = NULL; rsrc->mapped = NULL; rsrc->mtx = NULL;
 		return(1);
 	}
+#ifdef MAP_FILE			/* just matrix data -- leave metadata */
 	if (rdst->mapped)
-		return(0);	/* XXX can't handle this case */
-				/* just matrix data -- leave metadata */
-	if (rdst->mtx) free(rdst->mtx);
+		munmap(rdst->mapped, mapped_size(rdst));
+	else
+#endif
+	if (rdst->mtx)
+		free(rdst->mtx);
+	rdst->mapped = rsrc->mapped;
 	rdst->mtx = rsrc->mtx;
-	rsrc->mtx = NULL;
+	rsrc->mapped = NULL; rsrc->mtx = NULL;
 	return(1);
 }