--- ray/src/px/protate.c	1990/06/26 09:09:35	1.5
+++ ray/src/px/protate.c	1991/11/12 16:04:09	2.1
@@ -1,20 +1,26 @@
-/* Copyright (c) 1988 Regents of the University of California */
+/* Copyright (c) 1991 Regents of the University of California */
 
 #ifndef lint
 static char SCCSid[] = "$SunId$ LBL";
 #endif
+
 /*
  * prot.c - program to rotate picture file 90 degrees clockwise.
  *
  *	2/26/88
  */
 
-#include <stdio.h>
+#include "standard.h"
 
 #include "color.h"
 
+#include "resolu.h"
+
+int	order;				/* input scanline order */
 int	xres, yres;			/* input resolution */
 
+int	correctorder = 0;		/* order correction? */
+
 char	buf[1<<20];			/* output buffer */
 
 int	nrows;				/* number of rows output at once */
@@ -23,7 +29,10 @@ int	nrows;				/* number of rows output at once */
 
 char	*progname;
 
+#define neworder()	(correctorder ? order : \
+			(order^(order&YMAJOR?YDECR:XDECR)^YMAJOR))
 
+
 main(argc, argv)
 int	argc;
 char	*argv[];
@@ -32,8 +41,12 @@ char	*argv[];
 
 	progname = argv[0];
 
+	if (argc > 2 && !strcmp(argv[1], "-c")) {
+		correctorder++;
+		argc--; argv++;
+	}
 	if (argc != 2 && argc != 3) {
-		fprintf(stderr, "Usage: %s infile [outfile]\n", progname);
+		fprintf(stderr, "Usage: %s [-c] infile [outfile]\n", progname);
 		exit(1);
 	}
 	if ((fin = fopen(argv[1], "r")) == NULL) {
@@ -44,17 +57,20 @@ char	*argv[];
 		fprintf(stderr, "%s: cannot open\n", argv[2]);
 		exit(1);
 	}
-					/* copy header */
-	copyheader(fin, stdout);
+					/* transfer header */
+	if (checkheader(fin, COLRFMT, stdout) < 0) {
+		fprintf(stderr, "%s: not a Radiance picture\n", progname);
+		exit(1);
+	}
 					/* add new header info. */
 	printf("%s\n\n", progname);
 					/* get picture size */
-	if (fgetresolu(&xres, &yres, fin) != (YMAJOR|YDECR)) {
+	if ((order = fgetresolu(&xres, &yres, fin)) < 0) {
 		fprintf(stderr, "%s: bad picture size\n", progname);
 		exit(1);
 	}
 					/* write new picture size */
-	fputresolu(YMAJOR|YDECR, yres, xres, stdout);
+	fputresolu(neworder(), yres, xres, stdout);
 					/* compute buffer capacity */
 	nrows = sizeof(buf)/sizeof(COLR)/yres;
 	rotate(fin);			/* rotate the image */