Some initial work for implementing wireframe

utils/wireframe.pl

@@ -0,0 +1,105 @@
+#!/usr/bin/perl
+# This script exports experimental G-code for wireframe printing
+# (inspired by the brilliant WirePrint concept)
+
+use strict;
+use warnings;
+
+BEGIN {
+    use FindBin;
+    use lib "$FindBin::Bin/../lib";
+}
+
+use Getopt::Long qw(:config no_auto_abbrev);
+use PDF::API2;
+use Slic3r;
+use Slic3r::ExtrusionPath ':roles';
+use Slic3r::Geometry qw(scale unscale X Y);
+
+my %opt = (
+    step_height => 10,
+);
+{
+    my %options = (
+        'help'                  => sub { usage() },
+        'output|o=s'            => \$opt{output_file},
+        'step-height|h=f'       => \$opt{step_height},
+        'nozzle-angle|a=f'      => \$opt{nozzle_angle},
+    );
+    GetOptions(%options) or usage(1);
+    $opt{output_file} or usage(1);
+    ### Input file is not needed until we use hard-coded geometry:
+    ### $ARGV[0] or usage(1);
+}
+
+{
+    my $flow = Slic3r::Flow->new(
+        width           => 0.35,
+        height          => 0.35,
+        nozzle_diameter => 0.35,
+        bridge          => 1,
+    );
+    
+    my $section;
+    
+    # build a square section
+    {
+        my $dist = 2 * $opt{step_height};  # horizontal step
+        my $side_modules = 3;
+        my @points = (
+            [0,0],
+            (map [$_*$dist, 0], 1..$side_modules),
+            (map [$side_modules*$dist, $_*$dist], 1..$side_modules),
+            (map [($_-1)*$dist, $side_modules*$dist], reverse 1..$side_modules),
+            (map [0, ($_-1)*$dist], reverse 1..$side_modules),
+        );
+        pop @points;  # prevent coinciding endpoints
+        $section = Slic3r::Polygon->new_scale(@points);
+    }
+    my $section_loop = Slic3r::ExtrusionLoop->new_from_paths(
+        Slic3r::ExtrusionPath->new(
+            polyline        => $section->split_at_first_point,
+            role            => EXTR_ROLE_BRIDGE,
+            mm3_per_mm      => $flow->mm3_per_mm,
+            width           => $flow->width,
+            height          => $flow->height,
+        )
+    );
+    
+    my $vertical_steps = 3;
+    
+    open my $fh, '>', $opt{output_file};
+    my $gcodegen = Slic3r::GCode->new(
+        layer_count => $vertical_steps,
+    );
+    {
+        my $print_config = Slic3r::Config::Print->new;
+        $gcodegen->set_extruders([0], $print_config);
+        $gcodegen->set_extruder(0);
+    }
+    
+    print $fh "G21 ; set units to millimeters\n";
+    print $fh "G90 ; use absolute coordinates\n";
+    
+    # print one section on layer 0
+    $gcodegen->extrude_loop($section_loop);
+    
+    close $fh;
+}
+
+sub usage {
+    my ($exit_code) = @_;
+    
+    print <<"EOF";
+Usage: wireframe.pl [ OPTIONS ] file.stl
+
+    --help              Output this usage screen and exit
+    --output, -o        Write to the specified file
+    --step-height, -h   Use the specified step height
+    --nozzle-angle, -a  Max nozzle angle
+    
+EOF
+    exit ($exit_code || 0);
+}
+
+__END__