--- ray/src/util/rtpict.pl	2020/03/14 20:09:55	2.14
+++ ray/src/util/rtpict.pl	2020/04/08 00:58:32	2.16
@@ -1,5 +1,5 @@
 #!/usr/bin/perl -w
-# RCSid $Id: rtpict.pl,v 2.14 2020/03/14 20:09:55 greg Exp $
+# RCSid $Id: rtpict.pl,v 2.16 2020/04/08 00:58:32 greg Exp $
 #
 # Run rtrace in parallel mode to simulate rpict -n option
 # May also be used to render layered images with -o* option
@@ -11,7 +11,7 @@ use strict;
 my $nprocs = 1;
 # rtrace options and the associated number of arguments
 my %rtraceC = ('-dt',1, '-dc',1, '-dj',1, '-ds',1, '-dr',1, '-dp',1,
-		'-ss',1, '-st',1, '-e',1, '-am',1,
+		'-ss',1, '-st',1, '-e',1, '-am',1, '-P',1, '-PP',1,
 		'-ab',1, '-af',1, '-ai',1, '-aI',1, '-ae',1, '-aE',1,
 		'-av',3, '-aw',1, '-aa',1, '-ar',1, '-ad',1, '-as',1,
 		'-me',3, '-ma',3, '-mg',1, '-ms',1, '-lr',1, '-lw',1);
@@ -186,9 +186,11 @@ if (! -d $outdir) {
 foreach my $oval (split //, $outlyr) {
 	die "Duplicate or unsupported type '$oval' in -o$outlyr\n"
 					if (!defined $rtoutC{$oval});
+	my $outfile = "$outdir/$rtoutC{$oval}";
+	die "File '$outfile' already exists\n" if (-e $outfile);
 	my ($otyp) = ($rtoutC{$oval} =~ /(\.[^.]+)$/);
 	push @rsplitA, $rcodeC{$otyp}[0];
-	push @rsplitA, qq{'$rcodeC{$otyp}[1] > "$outdir/$rtoutC{$oval}"'};
+	push @rsplitA, qq{'$rcodeC{$otyp}[1] > "$outfile"'};
 	delete $rtoutC{$oval};
 }
 			# call rtrace + rsplit