concentric - new superfast infill pattern

MANIFEST

@@ -10,6 +10,7 @@ lib/Slic3r/ExtrusionPath/Collection.pm
 lib/Slic3r/Fill.pm
 lib/Slic3r/Fill/ArchimedeanChords.pm
 lib/Slic3r/Fill/Base.pm
+lib/Slic3r/Fill/Concentric.pm
 lib/Slic3r/Fill/Flowsnake.pm
 lib/Slic3r/Fill/HilbertCurve.pm
 lib/Slic3r/Fill/Line.pm

lib/Slic3r/Config.pm

@@ -95,12 +95,12 @@ our $Options = {
     'fill_pattern' => {
         label   => 'Fill pattern',
         type    => 'select',
-        values  => [qw(rectilinear line hilbertcurve archimedeanchords octagramspiral)],
+        values  => [qw(rectilinear line concentric hilbertcurve archimedeanchords octagramspiral)],
     },
     'solid_fill_pattern' => {
         label   => 'Solid fill pattern',
         type    => 'select',
-        values  => [qw(rectilinear hilbertcurve archimedeanchords octagramspiral)],
+        values  => [qw(rectilinear concentric hilbertcurve archimedeanchords octagramspiral)],
     },
     'fill_density' => {
         label   => 'Fill density',

lib/Slic3r/Fill.pm

@@ -3,6 +3,7 @@ use Moo;
 
 use Slic3r::Fill::ArchimedeanChords;
 use Slic3r::Fill::Base;
+use Slic3r::Fill::Concentric;
 use Slic3r::Fill::Flowsnake;
 use Slic3r::Fill::HilbertCurve;
 use Slic3r::Fill::Line;
@@ -26,6 +27,7 @@ our %FillTypes = (
     octagramspiral      => 'Slic3r::Fill::OctagramSpiral',
     hilbertcurve        => 'Slic3r::Fill::HilbertCurve',
     line                => 'Slic3r::Fill::Line',
+    concentric          => 'Slic3r::Fill::Concentric',
 );
 
 sub BUILD {

lib/Slic3r/Fill/Concentric.pm

@@ -0,0 +1,54 @@
+package Slic3r::Fill::Concentric;
+use Moo;
+
+extends 'Slic3r::Fill::Base';
+
+use XXX;
+
+sub fill_surface {
+    my $self = shift;
+    my ($surface, %params) = @_;
+    
+    # no rotation is supported for this infill pattern
+    
+    my $flow_width_res = $params{flow_width} / $Slic3r::resolution;
+    my $distance = $flow_width_res / $params{density};
+    
+    my @contour_loops = ();
+    my @hole_loops = ();
+    my @last_offsets = ($surface->expolygon->offset_ex($distance));
+    while (@last_offsets) {
+        my @new_offsets = ();
+        foreach my $expolygon (@last_offsets) {
+            my @offsets = $expolygon->offset_ex(-$distance);
+            foreach my $offset (@offsets) {
+                push @new_offsets, $offset;
+                push @contour_loops, $offset->contour;
+                push @hole_loops, $offset->holes;
+            }
+        }
+        @last_offsets = @new_offsets;
+    }
+    
+    my @loops = (@contour_loops, reverse @hole_loops);
+    
+    # make paths
+    my @paths = ();
+    my $cur_pos = Slic3r::Point->new(0,0);
+    foreach my $loop (map Slic3r::ExtrusionLoop->cast($_), @loops) {
+        # find the point of the loop that is closest to the current extruder position
+        $cur_pos = $loop->nearest_point_to($cur_pos);
+        
+        # split the loop at the starting point and make a path
+        my $path = $loop->split_at($cur_pos);
+    
+        # clip the path to avoid the extruder to get exactly on the first point of the loop
+        $path->clip_end($Slic3r::flow_width / $Slic3r::resolution);
+        
+        push @paths, $path->p;
+    }
+    
+    return @paths;
+}
+
+1;