sl2/slicer.pl: add command-line options

sl2/README

@@ -6,3 +6,7 @@ were then falsely closed and yielded bogus toolpaths.
 This slicer uses very strict conditions for horizontality: all the
 points of a horizontal facet must have identical Z coordinates. It
 also implicitly ensures that all paths are closed.
+
+sl2/slicer.pl supports the same command-line options as sfc/slicer.py
+and can be used as drop-in replacement, provided that the toolpaths
+are re-aligned afterwards.

sl2/slicer.pl

@@ -13,12 +13,62 @@
 
 
 $epsilon = 0.0001;	# cutting offset
-$height = 10;		# height of workpiece
+$height = undef;	# height of workpiece
-$margin = 5;		# margin of workpiece box
+$margin = undef;	# margin of workpiece box
 $end = 0;		# offset to add at the last layer
-$flip = 1;		# flip piece
+$flip = 0;		# flip piece
-$z0 = -35;		# reference tool position
+$z_step = undef;	# maximum increase of milling depth
-$z_step = 1;
+
+
+#----- Command-line processing ------------------------------------------------
+
+
+sub usage
+{
+	print STDERR <<"EOF";
+usage: $0 [-a (top|bottom)(+|-)offset] [-f] [-h height]
+    [-m tolerance] [-p piece_distance] [-o z_offset] [-s max_step] [file.stl]
+
+  -a alignment	TO DO
+  -f		flip the model around the Y axis
+  -h height	workpiece height (default: use model dimensions)
+  -m tolerance	compatibility with sfc/slicer.py, has no meaning here
+  -p piece_distance
+		draw a rectangular workpiece at the specified xy distance
+		around the model (default: none)
+  -o z_offset	Z adjustment of final layer
+  -s max_step	maximum Z step (default: unlimited)
+EOF
+	exit(1);
+}
+
+
+while ($ARGV[0] =~ /^-/) {
+	my $opt = shift @ARGV;
+	if ($opt eq "-a") {
+		# @@@ implement later
+		shift @ARGV;
+	} elsif ($opt eq "-f") {
+		$flip = 1;
+	} elsif ($opt eq "-h") {
+		$height = shift @ARGV;
+		&usage unless defined $height;
+	} elsif ($opt eq "-m") {
+		# @@@ not used - support for compatibility
+		shift @ARGV;
+	} elsif ($opt eq "-o") {
+		$end = shift @ARGV;
+		&usage unless defined $end;
+	} elsif ($opt eq "-p") {
+		$margin = shift @ARGV;
+		&usage unless defined $margin;
+	} elsif ($opt eq "-s") {
+		$z_step = shift @ARGV;
+		&usage unless defined $z_step;
+	} else {
+		&usage;
+	}
+}
 
 
 #----- Read the STL mesh ------------------------------------------------------
@@ -63,9 +113,11 @@ print STDERR "bbox\t($xmin, $ymin, $zmin)\n\t($xmax, $ymax, $zmax)\n";
 
 #----- Calculate Z offset -----------------------------------------------------
 
+$height = $zmax - $zmin unless defined $height;
+
 # align with bottom (zmin == 0), z_pos = height - zoff
 
-$z_off = $z0 - $zmin - $height;
+$z_off = -$zmin - $height;
 $z_pos = $height + $zmin;