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			518 lines
		
	
	
	
		
			22 KiB
		
	
	
	
		
			Perl
		
	
	
	
	
	
			
		
		
	
	
			518 lines
		
	
	
	
		
			22 KiB
		
	
	
	
		
			Perl
		
	
	
	
	
	
| package Slic3r::Layer::Region;
 | ||
| use Moo;
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| 
 | ||
| use List::Util qw(sum first);
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| use Slic3r::ExtrusionPath ':roles';
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| use Slic3r::Flow ':roles';
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| use Slic3r::Geometry qw(PI A B scale unscale chained_path points_coincide);
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| use Slic3r::Geometry::Clipper qw(union_ex diff_ex intersection_ex 
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|     offset offset_ex offset2 offset2_ex union_pt diff intersection
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|     union diff intersection_pl);
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| use Slic3r::Surface ':types';
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| 
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| has 'layer' => (
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|     is          => 'ro',
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|     weak_ref    => 1,
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|     required    => 1,
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|     handles     => [qw(id slice_z print_z height object print)],
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| );
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| has 'region'            => (is => 'ro', required => 1, handles => [qw(config)]);
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| has 'infill_area_threshold' => (is => 'lazy');
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| has 'overhang_width'    => (is => 'lazy');
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| 
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| # collection of surfaces generated by slicing the original geometry
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| # divided by type top/bottom/internal
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| has 'slices' => (is => 'rw', default => sub { Slic3r::Surface::Collection->new });
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| 
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| # collection of extrusion paths/loops filling gaps
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| has 'thin_fills' => (is => 'rw', default => sub { Slic3r::ExtrusionPath::Collection->new });
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| 
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| # collection of surfaces for infill generation
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| has 'fill_surfaces' => (is => 'rw', default => sub { Slic3r::Surface::Collection->new });
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| 
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| # ordered collection of extrusion paths/loops to build all perimeters
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| has 'perimeters' => (is => 'rw', default => sub { Slic3r::ExtrusionPath::Collection->new });
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| 
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| # ordered collection of extrusion paths to fill surfaces
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| has 'fills' => (is => 'rw', default => sub { Slic3r::ExtrusionPath::Collection->new });
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| 
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| sub _build_overhang_width {
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|     my $self = shift;
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|     my $threshold_rad = PI/2 - atan2($self->flow(FLOW_ROLE_PERIMETER)->width / $self->height / 2, 1);
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|     return scale($self->height * ((cos $threshold_rad) / (sin $threshold_rad)));
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| }
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| 
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| sub _build_infill_area_threshold {
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|     my $self = shift;
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|     return $self->flow(FLOW_ROLE_SOLID_INFILL)->scaled_spacing ** 2;
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| }
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| 
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| sub flow {
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|     my ($self, $role, $bridge, $width) = @_;
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|     return $self->region->flow(
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|         $role,
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|         $self->layer->height,
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|         $bridge // 0,
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|         $self->layer->id == 0,
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|         $width,
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|     );
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| }
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| 
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| sub make_perimeters {
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|     my $self = shift;
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|     
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|     my $perimeter_flow      = $self->flow(FLOW_ROLE_PERIMETER);
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|     my $mm3_per_mm          = $perimeter_flow->mm3_per_mm($self->height);
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|     my $pwidth              = $perimeter_flow->scaled_width;
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|     my $pspacing            = $perimeter_flow->scaled_spacing;
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|     my $solid_infill_flow   = $self->flow(FLOW_ROLE_SOLID_INFILL);
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|     my $ispacing            = $solid_infill_flow->scaled_spacing;
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|     my $gap_area_threshold  = $pwidth ** 2;
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|     
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|     $self->perimeters->clear;
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|     $self->fill_surfaces->clear;
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|     $self->thin_fills->clear;
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|     
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|     my @contours    = ();    # array of Polygons with ccw orientation
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|     my @holes       = ();    # array of Polygons with cw orientation
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|     my @thin_walls  = ();    # array of ExPolygons
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|     my @gaps        = ();    # array of ExPolygons
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|     
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|     # we need to process each island separately because we might have different
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|     # extra perimeters for each one
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|     foreach my $surface (@{$self->slices}) {
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|         # detect how many perimeters must be generated for this island
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|         my $loop_number = $self->config->perimeters + ($surface->extra_perimeters || 0);
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|         
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|         my @last = @{$surface->expolygon};
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|         my @last_gaps = ();
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|         if ($loop_number > 0) {
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|             # we loop one time more than needed in order to find gaps after the last perimeter was applied
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|             for my $i (1 .. ($loop_number+1)) {  # outer loop is 1
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|                 my @offsets = ();
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|                 if ($i == 1) {
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|                     # the minimum thickness of a single loop is:
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|                     # width/2 + spacing/2 + spacing/2 + width/2
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|                     @offsets = @{offset2(\@last, -(0.5*$pwidth + 0.5*$pspacing - 1), +(0.5*$pspacing - 1))};
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|                     
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|                     # look for thin walls
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|                     if ($self->config->thin_walls) {
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|                         my $diff = diff_ex(
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|                             \@last,
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|                             offset(\@offsets, +0.5*$pwidth),
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|                             1,  # medial axis requires non-overlapping geometry
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|                         );
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|                         push @thin_walls, @$diff;
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|                     }
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|                 } else {
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|                     @offsets = @{offset2(\@last, -(1.5*$pspacing - 1), +(0.5*$pspacing - 1))};
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|                 
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|                     # look for gaps
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|                     if ($self->print->config->gap_fill_speed > 0 && $self->config->fill_density > 0) {
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|                         my $diff = diff_ex(
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|                             offset(\@last, -0.5*$pspacing),
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|                             offset(\@offsets, +0.5*$pspacing),
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|                         );
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|                         push @gaps, @last_gaps = grep abs($_->area) >= $gap_area_threshold, @$diff;
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|                     }
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|                 }
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|             
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|                 last if !@offsets;
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|                 last if $i > $loop_number; # we were only looking for gaps this time
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|             
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|                 # clone polygons because these ExPolygons will go out of scope very soon
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|                 @last = @offsets;
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|                 foreach my $polygon (@offsets) {
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|                     if ($polygon->is_counter_clockwise) {
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|                         push @contours, $polygon;
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|                     } else {
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|                         push @holes, $polygon;
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|                     }
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|                 }
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|             }
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|         }
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|         
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|         # make sure we don't infill narrow parts that are already gap-filled
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|         # (we only consider this surface's gaps to reduce the diff() complexity)
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|         @last = @{diff(\@last, [ map @$_, @last_gaps ])};
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|         
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|         # create one more offset to be used as boundary for fill
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|         # we offset by half the perimeter spacing (to get to the actual infill boundary)
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|         # and then we offset back and forth by half the infill spacing to only consider the
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|         # non-collapsing regions
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|         $self->fill_surfaces->append(
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|             map Slic3r::Surface->new(expolygon => $_, surface_type => S_TYPE_INTERNAL),  # use a bogus surface type
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|             @{offset2_ex(
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|                 [ map @{$_->simplify_p(&Slic3r::SCALED_RESOLUTION)}, @{union_ex(\@last)} ],
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|                 -($pspacing/2 + $ispacing/2),
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|                 +$ispacing/2,
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|             )}
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|         );
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|     }
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|     
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|     # process thin walls by collapsing slices to single passes
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|     my @thin_wall_polylines = ();
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|     if (@thin_walls) {
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|         # the following offset2 ensures almost nothing in @thin_walls is narrower than $min_width
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|         # (actually, something larger than that still may exist due to mitering or other causes)
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|         my $min_width = $pwidth / 4;
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|         @thin_walls = @{offset2_ex([ map @$_, @thin_walls ], -$min_width/2, +$min_width/2)};
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|         
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|         # the maximum thickness of our thin wall area is equal to the minimum thickness of a single loop
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|         @thin_wall_polylines = map @{$_->medial_axis($pwidth + $pspacing, $min_width)}, @thin_walls;
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|         Slic3r::debugf "  %d thin walls detected\n", scalar(@thin_wall_polylines) if $Slic3r::debug;
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|         
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|         if (0) {
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|             require "Slic3r/SVG.pm";
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|             Slic3r::SVG::output(
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|                 "medial_axis.svg",
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|                 no_arrows => 1,
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|                 expolygons      => \@thin_walls,
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|                 green_polylines => [ map $_->polygon->split_at_first_point, @{$self->perimeters} ],
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|                 red_polylines   => \@thin_wall_polylines,
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|             );
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|         }
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|     }
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|     
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|     # find nesting hierarchies separately for contours and holes
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|     my $contours_pt = union_pt(\@contours);
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|     my $holes_pt    = union_pt(\@holes);
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|     
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|     # prepare a coderef for traversing the PolyTree object
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|     # external contours are root items of $contours_pt
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|     # internal contours are the ones next to external
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|     my $traverse;
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|     $traverse = sub {
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|         my ($polynodes, $depth, $is_contour) = @_;
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|         
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|         # convert all polynodes to ExtrusionLoop objects
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|         my $collection = Slic3r::ExtrusionPath::Collection->new;
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|         my @children = ();
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|         foreach my $polynode (@$polynodes) {
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|             my $polygon = ($polynode->{outer} // $polynode->{hole})->clone;
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|             
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|             # return ccw contours and cw holes
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|             # GCode.pm will convert all of them to ccw, but it needs to know
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|             # what the holes are in order to compute the correct inwards move
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|             if ($is_contour) {
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|                 $polygon->make_counter_clockwise;
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|             } else {
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|                 $polygon->make_clockwise;
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|             }
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|             
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|             my $role = EXTR_ROLE_PERIMETER;
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|             if ($is_contour ? $depth == 0 : !@{ $polynode->{children} }) {
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|                 # external perimeters are root level in case of contours
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|                 # and items with no children in case of holes
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|                 $role = EXTR_ROLE_EXTERNAL_PERIMETER;
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|             } elsif ($depth == 1 && $is_contour) {
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|                 $role = EXTR_ROLE_CONTOUR_INTERNAL_PERIMETER;
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|             }
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|             
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|             $collection->append(Slic3r::ExtrusionLoop->new(
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|                 polygon         => $polygon,
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|                 role            => $role,
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|                 mm3_per_mm      => $mm3_per_mm,
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|             ));
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|             
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|             # save the children
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|             push @children, $polynode->{children};
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|         }
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| 
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|         # if we're handling the top-level contours, add thin walls as candidates too
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|         # in order to include them in the nearest-neighbor search
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|         if ($is_contour && $depth == 0) {
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|             foreach my $polyline (@thin_wall_polylines) {
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|                 $collection->append(Slic3r::ExtrusionPath->new(
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|                     polyline        => $polyline,
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|                     role            => EXTR_ROLE_EXTERNAL_PERIMETER,
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|                     mm3_per_mm      => $mm3_per_mm,
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|                 ));
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|             }
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|         }
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|         
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|         # use a nearest neighbor search to order these children
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|         # TODO: supply second argument to chained_path() too?
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|         my $sorted_collection = $collection->chained_path_indices(0);
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|         my @orig_indices = @{$sorted_collection->orig_indices};
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|         
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|         my @loops = ();
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|         foreach my $loop (@$sorted_collection) {
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|             my $orig_index = shift @orig_indices;
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|             
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|             if ($loop->isa('Slic3r::ExtrusionPath')) {
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|                 push @loops, $loop->clone;
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|             } else {
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|                 # if this is an external contour find all holes belonging to this contour(s)
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|                 # and prepend them
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|                 if ($is_contour && $depth == 0) {
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|                     # $loop is the outermost loop of an island
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|                     my @holes = ();
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|                     for (my $i = 0; $i <= $#$holes_pt; $i++) {
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|                         if ($loop->polygon->contains_point($holes_pt->[$i]{outer}->first_point)) {
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|                             push @holes, splice @$holes_pt, $i, 1;  # remove from candidates to reduce complexity
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|                             $i--;
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|                         }
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|                     }
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|                     
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|                     # order holes efficiently
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|                     @holes = @holes[@{chained_path([ map {($_->{outer} // $_->{hole})->first_point} @holes ])}];
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|                     
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|                     push @loops, reverse map $traverse->([$_], 0, 0), @holes;
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|                 }
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|                 
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|                 # traverse children and prepend them to this loop
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|                 push @loops, $traverse->($children[$orig_index], $depth+1, $is_contour);
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|                 push @loops, $loop->clone;
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|             }
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|         }
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|         return @loops;
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|     };
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|     
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|     # order loops from inner to outer (in terms of object slices)
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|     my @loops = $traverse->($contours_pt, 0, 1);
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|     
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|     # if brim will be printed, reverse the order of perimeters so that
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|     # we continue inwards after having finished the brim
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|     # TODO: add test for perimeter order
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|     @loops = reverse @loops
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|         if $self->print->config->external_perimeters_first
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|             || ($self->layer->id == 0 && $self->print->config->brim_width > 0);
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|     
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|     # append perimeters
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|     $self->perimeters->append(@loops);
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|     
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|     # fill gaps
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|     {
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|         my $fill_gaps = sub {
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|             my ($min, $max, $w) = @_;
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|             
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|             my $this = diff_ex(
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|                 offset2([ map @$_, @gaps ], -$min/2, +$min/2),
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|                 offset2([ map @$_, @gaps ], -$max/2, +$max/2),
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|                 1,
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|             );
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|             
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|             my $flow = $self->flow(FLOW_ROLE_SOLID_INFILL, 0, $w);
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|             my %path_args = (
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|                 role        => EXTR_ROLE_GAPFILL,
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|                 mm3_per_mm  => $flow->mm3_per_mm($self->height),
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|             );
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|             my @polylines = map @{$_->medial_axis($max, $min/2)}, @$this;
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|             $self->thin_fills->append(map {
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|                 $_->isa('Slic3r::Polygon')
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|                     ? Slic3r::ExtrusionLoop->new(polygon => $_, %path_args)->split_at_first_point  # should we keep these as loops?
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|                     : Slic3r::ExtrusionPath->new(polyline => $_, %path_args),
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|             } @polylines);
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| 
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|             Slic3r::debugf "  %d gaps filled with extrusion width = %s\n", scalar @$this, $w
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|                 if @$this;
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|         };
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|         
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|         # where $pwidth < thickness < 2*$pspacing, infill with width = 1.5*$pwidth
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|         # where 0.5*$pwidth < thickness < $pwidth, infill with width = 0.5*$pwidth
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|         $fill_gaps->($pwidth, 2*$pspacing, unscale 1.5*$pwidth);
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|         $fill_gaps->(0.5*$pwidth, $pwidth, unscale 0.5*$pwidth);
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|     }
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| }
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| 
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| sub prepare_fill_surfaces {
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|     my $self = shift;
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|     
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|     # if no solid layers are requested, turn top/bottom surfaces to internal
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|     if ($self->config->top_solid_layers == 0) {
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|         $_->surface_type(S_TYPE_INTERNAL) for @{$self->fill_surfaces->filter_by_type(S_TYPE_TOP)};
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|     }
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|     if ($self->config->bottom_solid_layers == 0) {
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|         $_->surface_type(S_TYPE_INTERNAL)
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|             for @{$self->fill_surfaces->filter_by_type(S_TYPE_BOTTOM)}, @{$self->fill_surfaces->filter_by_type(S_TYPE_BOTTOMBRIDGE)};
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|     }
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|         
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|     # turn too small internal regions into solid regions according to the user setting
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|     if ($self->config->fill_density > 0) {
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|         my $min_area = scale scale $self->config->solid_infill_below_area; # scaling an area requires two calls!
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|         $_->surface_type(S_TYPE_INTERNALSOLID)
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|             for grep { $_->area <= $min_area } @{$self->fill_surfaces->filter_by_type(S_TYPE_INTERNAL)};
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|     }
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| }
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| 
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| sub process_external_surfaces {
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|     my ($self, $lower_layer) = @_;
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|     
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|     my @surfaces = @{$self->fill_surfaces};
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|     my $margin = scale &Slic3r::EXTERNAL_INFILL_MARGIN;
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|     
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|     my @bottom = ();
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|     foreach my $surface (grep $_->is_bottom, @surfaces) {
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|         my $grown = $surface->expolygon->offset_ex(+$margin);
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|         
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|         # detect bridge direction before merging grown surfaces otherwise adjacent bridges
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|         # would get merged into a single one while they need different directions
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|         # also, supply the original expolygon instead of the grown one, because in case
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|         # of very thin (but still working) anchors, the grown expolygon would go beyond them
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|         my $angle = $lower_layer
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|             ? $self->_detect_bridge_direction($surface->expolygon, $lower_layer)
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|             : undef;
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|         
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|         push @bottom, map $surface->clone(expolygon => $_, bridge_angle => $angle), @$grown;
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|     }
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|     
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|     my @top = ();
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|     foreach my $surface (grep $_->surface_type == S_TYPE_TOP, @surfaces) {
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|         # give priority to bottom surfaces
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|         my $grown = diff_ex(
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|             $surface->expolygon->offset(+$margin),
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|             [ map $_->p, @bottom ],
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|         );
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|         push @top, map $surface->clone(expolygon => $_), @$grown;
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|     }
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|     
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|     # if we're slicing with no infill, we can't extend external surfaces
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|     # over non-existent infill
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|     my @fill_boundaries = $self->config->fill_density > 0
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|         ? @surfaces
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|         : grep $_->surface_type != S_TYPE_INTERNAL, @surfaces;
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|     
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|     # intersect the grown surfaces with the actual fill boundaries
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|     my @new_surfaces = ();
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|     foreach my $group (@{Slic3r::Surface::Collection->new(@top, @bottom)->group}) {
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|         push @new_surfaces,
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|             map $group->[0]->clone(expolygon => $_),
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|             @{intersection_ex(
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|                 [ map $_->p, @$group ],
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|                 [ map $_->p, @fill_boundaries ],
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|                 1,  # to ensure adjacent expolygons are unified
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|             )};
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|     }
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|     
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|     # subtract the new top surfaces from the other non-top surfaces and re-add them
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|     my @other = grep $_->surface_type != S_TYPE_TOP && !$_->is_bottom, @surfaces;
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|     foreach my $group (@{Slic3r::Surface::Collection->new(@other)->group}) {
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|         push @new_surfaces, map $group->[0]->clone(expolygon => $_), @{diff_ex(
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|             [ map $_->p, @$group ],
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|             [ map $_->p, @new_surfaces ],
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|         )};
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|     }
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|     $self->fill_surfaces->clear;
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|     $self->fill_surfaces->append(@new_surfaces);
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| }
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| 
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| sub _detect_bridge_direction {
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|     my ($self, $expolygon, $lower_layer) = @_;
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|     
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|     my $perimeter_flow  = $self->flow(FLOW_ROLE_PERIMETER);
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|     my $infill_flow     = $self->flow(FLOW_ROLE_INFILL);
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|     
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|     my $grown = $expolygon->offset(+$perimeter_flow->scaled_width);
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|     my @lower = @{$lower_layer->slices};       # expolygons
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|     
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|     # detect what edges lie on lower slices
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|     my @edges = (); # polylines
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|     foreach my $lower (@lower) {
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|         # turn bridge contour and holes into polylines and then clip them
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|         # with each lower slice's contour
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|         my @clipped = @{intersection_pl([ map $_->split_at_first_point, @$grown ], [$lower->contour])};
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|         if (@clipped == 2) {
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|             # If the split_at_first_point() call above happens to split the polygon inside the clipping area
 | ||
|             # we would get two consecutive polylines instead of a single one, so we use this ugly hack to 
 | ||
|             # recombine them back into a single one in order to trigger the @edges == 2 logic below.
 | ||
|             # This needs to be replaced with something way better.
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|             if (points_coincide($clipped[0][0], $clipped[-1][-1])) {
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|                 @clipped = (Slic3r::Polyline->new(@{$clipped[-1]}, @{$clipped[0]}));
 | ||
|             }
 | ||
|             if (points_coincide($clipped[-1][0], $clipped[0][-1])) {
 | ||
|                 @clipped = (Slic3r::Polyline->new(@{$clipped[0]}, @{$clipped[1]}));
 | ||
|             }
 | ||
|         }
 | ||
|         push @edges, @clipped;
 | ||
|     }
 | ||
|     
 | ||
|     Slic3r::debugf "Found bridge on layer %d with %d support(s)\n", $self->id, scalar(@edges);
 | ||
|     return undef if !@edges;
 | ||
|     
 | ||
|     my $bridge_angle = undef;
 | ||
|     
 | ||
|     if (0) {
 | ||
|         require "Slic3r/SVG.pm";
 | ||
|         Slic3r::SVG::output("bridge_$expolygon.svg",
 | ||
|             expolygons      => [ $expolygon ],
 | ||
|             red_expolygons  => [ @lower ],
 | ||
|             polylines       => [ @edges ],
 | ||
|         );
 | ||
|     }
 | ||
|     
 | ||
|     if (@edges == 2) {
 | ||
|         my @chords = map Slic3r::Line->new($_->[0], $_->[-1]), @edges;
 | ||
|         my @midpoints = map $_->midpoint, @chords;
 | ||
|         my $line_between_midpoints = Slic3r::Line->new(@midpoints);
 | ||
|         $bridge_angle = Slic3r::Geometry::rad2deg_dir($line_between_midpoints->direction);
 | ||
|     } elsif (@edges == 1) {
 | ||
|         # TODO: this case includes both U-shaped bridges and plain overhangs;
 | ||
|         # we need a trapezoidation algorithm to detect the actual bridged area
 | ||
|         # and separate it from the overhang area.
 | ||
|         # in the mean time, we're treating as overhangs all cases where
 | ||
|         # our supporting edge is a straight line
 | ||
|         if (@{$edges[0]} > 2) {
 | ||
|             my $line = Slic3r::Line->new($edges[0]->[0], $edges[0]->[-1]);
 | ||
|             $bridge_angle = Slic3r::Geometry::rad2deg_dir($line->direction);
 | ||
|         }
 | ||
|     } elsif (@edges) {
 | ||
|         # inset the bridge expolygon; we'll use this one to clip our test lines
 | ||
|         my $inset = $expolygon->offset_ex($infill_flow->scaled_width);
 | ||
|         
 | ||
|         # detect anchors as intersection between our bridge expolygon and the lower slices
 | ||
|         my $anchors = intersection_ex(
 | ||
|             $grown,
 | ||
|             [ map @$_, @lower ],
 | ||
|             1,  # safety offset required to avoid Clipper from detecting empty intersection while Boost actually found some @edges
 | ||
|         );
 | ||
|         
 | ||
|         if (@$anchors) {
 | ||
|             # we'll now try several directions using a rudimentary visibility check:
 | ||
|             # bridge in several directions and then sum the length of lines having both
 | ||
|             # endpoints within anchors
 | ||
|             my %directions = ();  # angle => score
 | ||
|             my $angle_increment = PI/36; # 5°
 | ||
|             my $line_increment = $infill_flow->scaled_width;
 | ||
|             for (my $angle = 0; $angle <= PI; $angle += $angle_increment) {
 | ||
|                 # rotate everything - the center point doesn't matter
 | ||
|                 $_->rotate($angle, [0,0]) for @$inset, @$anchors;
 | ||
|             
 | ||
|                 # generate lines in this direction
 | ||
|                 my $bounding_box = Slic3r::Geometry::BoundingBox->new_from_points([ map @$_, map @$_, @$anchors ]);
 | ||
|             
 | ||
|                 my @lines = ();
 | ||
|                 for (my $x = $bounding_box->x_min; $x <= $bounding_box->x_max; $x += $line_increment) {
 | ||
|                     push @lines, Slic3r::Polyline->new([$x, $bounding_box->y_min], [$x, $bounding_box->y_max]);
 | ||
|                 }
 | ||
|             
 | ||
|                 my @clipped_lines = map Slic3r::Line->new(@$_), @{ intersection_pl(\@lines, [ map @$_, @$inset ]) };
 | ||
|             
 | ||
|                 # remove any line not having both endpoints within anchors
 | ||
|                 # NOTE: these calls to contains_point() probably need to check whether the point 
 | ||
|                 # is on the anchor boundaries too
 | ||
|                 @clipped_lines = grep {
 | ||
|                     my $line = $_;
 | ||
|                     !(first { $_->contains_point($line->a) } @$anchors)
 | ||
|                         && !(first { $_->contains_point($line->b) } @$anchors);
 | ||
|                 } @clipped_lines;
 | ||
|             
 | ||
|                 # sum length of bridged lines
 | ||
|                 $directions{-$angle} = sum(map $_->length, @clipped_lines) // 0;
 | ||
|             }
 | ||
|         
 | ||
|             # this could be slightly optimized with a max search instead of the sort
 | ||
|             my @sorted_directions = sort { $directions{$a} <=> $directions{$b} } keys %directions;
 | ||
|     
 | ||
|             # the best direction is the one causing most lines to be bridged
 | ||
|             $bridge_angle = Slic3r::Geometry::rad2deg_dir($sorted_directions[-1]);
 | ||
|         }
 | ||
|     }
 | ||
|     
 | ||
|     Slic3r::debugf "  Optimal infill angle of bridge on layer %d is %d degrees\n",
 | ||
|         $self->id, $bridge_angle if defined $bridge_angle;
 | ||
|     
 | ||
|     return $bridge_angle;
 | ||
| }
 | ||
| 
 | ||
| 1;
 | 
