--- ray/src/util/fieldcomb.csh	2005/09/02 04:24:37	2.2
+++ ray/src/util/fieldcomb.csh	2005/09/02 14:43:43	2.3
@@ -1,5 +1,5 @@
 #!/bin/csh -f
-# RCSid $Id: fieldcomb.csh,v 2.2 2005/09/02 04:24:37 greg Exp $
+# RCSid $Id: fieldcomb.csh,v 2.3 2005/09/02 14:43:43 greg Exp $
 #
 # Combine alternate lines in full frames for field rendering
 #
@@ -8,17 +8,30 @@
 # If an odd number of frames is provided, the spare frame at the
 # end is linked to $spare_name for the next run
 #
-# Written by Greg Ward for Iebele Atelier in August 2005
+# Written by Greg Ward for Iebele Abel in August 2005
 #
 set spare_name=spare_fieldcomb_frame.pic
-if ($#argv > 1) then
-	if ("$argv[1]" == "-r") then
+set odd_first=0
+while ($#argv > 1)
+	switch ($argv[1])
+	case -r*:
 		set remove_orig
-		shift argv
-	endif
-endif
+		breaksw
+	case -o*:
+		set odd_first=1
+		breaksw
+	case -e*:
+		set odd_first=0
+		breaksw
+	default:
+		if ("$argv[1]" !~ -*) break
+		echo "Unknown option: $argv[1]"
+		exit 1
+	endsw
+	shift argv
+end
 if ($#argv < 2) then
-	echo "Usage: $0 [-r] field1.pic field2.pic .."
+	echo "Usage: $0 [-e|-o][-r] field1.pic field2.pic .."
 	exit 1
 endif
 set f1=$argv[1]:q
@@ -36,7 +49,7 @@ while ($curfi < $#fields)
 	@ nextfi = $curfi + 1
 	pcomb -e 'ro=ri(fld); go=gi(fld); bo=bi(fld)' \
 		-e 'yd=yres-1-y; odd=.5*yd-floor(.5*yd)-.25' \
-		-e 'fld=if(odd,1,2)' \
+		-e "fld=if(odd,2-$odd_first,1+$odd_first)" \
 		$fields[$curfi]:q $fields[$nextfi]:q \
 		> "${basenm}C$curfr.$ext"
 	if ($?remove_orig) rm $fields[$curfi]:q $fields[$nextfi]:q