PrusaSlicer-NonPlainar/lib/Slic3r/Layer.pm

431 lines
15 KiB
Perl

package Slic3r::Layer;
use Moo;
use Math::Clipper ':all';
use Slic3r::Geometry qw(scale collinear X Y A B PI rad2deg_dir bounding_box_center);
use Slic3r::Geometry::Clipper qw(union_ex diff_ex intersection_ex xor_ex is_counter_clockwise);
use XXX;
# a sequential number of layer, starting at 0
has 'id' => (
is => 'rw',
#isa => 'Int',
required => 1,
);
has 'slicing_errors' => (is => 'rw');
# collection of spare segments generated by slicing the original geometry;
# these need to be merged in continuos (closed) polylines
has 'lines' => (
is => 'rw',
#isa => 'ArrayRef[Slic3r::TriangleMesh::IntersectionLine]',
default => sub { [] },
);
# collection of surfaces generated by slicing the original geometry
has 'slices' => (is => 'ro', default => sub { [] });
# collection of polygons or polylines representing thin walls contained
# in the original geometry
has 'thin_walls' => (is => 'ro', default => sub { [] });
# collection of expolygons generated by offsetting the innermost perimeter(s)
# they represent boundaries of areas to fill
has 'fill_boundaries' => (is => 'ro', default => sub { [] });
# collection of polygons or polylines representing thin infill regions that
# need to be filled with a medial axis
has 'thin_fills' => (is => 'ro', default => sub { [] });
# collection of surfaces generated by clipping the slices to the fill boundaries
has 'surfaces' => (
is => 'rw',
#isa => 'ArrayRef[Slic3r::Surface]',
default => sub { [] },
);
# collection of surfaces for infill
has 'fill_surfaces' => (
is => 'rw',
#isa => 'ArrayRef[Slic3r::Surface]',
default => sub { [] },
);
# ordered collection of extrusion paths to build all perimeters
has 'perimeters' => (
is => 'rw',
#isa => 'ArrayRef[Slic3r::ExtrusionLoop]',
default => sub { [] },
);
# ordered collection of extrusion paths to build skirt loops
has 'skirts' => (
is => 'rw',
#isa => 'ArrayRef[Slic3r::ExtrusionLoop]',
default => sub { [] },
);
# ordered collection of extrusion paths to fill surfaces for support material
has 'support_fills' => (
is => 'rw',
#isa => 'Slic3r::ExtrusionPath::Collection',
);
# ordered collection of extrusion paths to fill surfaces
has 'fills' => (
is => 'rw',
#isa => 'ArrayRef[Slic3r::ExtrusionPath::Collection]',
default => sub { [] },
);
# Z used for slicing
sub slice_z {
my $self = shift;
if ($self->id == 0) {
return ($Slic3r::layer_height * $Slic3r::first_layer_height_ratio) / 2 / $Slic3r::resolution;
}
return (($Slic3r::layer_height * $Slic3r::first_layer_height_ratio)
+ (($self->id-1) * $Slic3r::layer_height)
+ ($Slic3r::layer_height/2)) / $Slic3r::resolution;
}
# Z used for printing
sub print_z {
my $self = shift;
return (($Slic3r::layer_height * $Slic3r::first_layer_height_ratio)
+ ($self->id * $Slic3r::layer_height)) / $Slic3r::resolution;
}
sub height {
my $self = shift;
return $self->id == 0
? ($Slic3r::layer_height * $Slic3r::first_layer_height_ratio)
: $Slic3r::layer_height;
}
sub add_line {
my $self = shift;
my ($line) = @_;
push @{ $self->lines }, $line;
return $line;
}
# build polylines from lines
sub make_surfaces {
my $self = shift;
my ($loops) = @_;
{
# merge everything
my $expolygons = union_ex($loops);
Slic3r::debugf " %d surface(s) having %d holes detected from %d polylines\n",
scalar(@$expolygons), scalar(map $_->holes, @$expolygons), scalar(@$loops);
push @{$self->slices},
map Slic3r::Surface->new(expolygon => $_, surface_type => 'internal'),
@$expolygons;
}
# the contours must be offsetted by half extrusion width inwards
{
my $distance = scale $Slic3r::flow_width / 2;
my @surfaces = @{$self->slices};
@{$self->slices} = ();
foreach my $surface (@surfaces) {
push @{$self->slices}, map Slic3r::Surface->new
(expolygon => $_, surface_type => 'internal'),
$surface->expolygon->offset_ex(-$distance);
}
# now detect thin walls by re-outgrowing offsetted surfaces and subtracting
# them from the original slices
my $outgrown = Math::Clipper::offset([ map $_->p, @{$self->slices} ], $distance);
my $diff = diff_ex(
[ map $_->p, @surfaces ],
$outgrown,
1,
);
# TODO: remove very small expolygons from diff before attempting to do medial axis
# (benchmark first)
push @{$self->thin_walls},
grep $_,
map $_->medial_axis(scale $Slic3r::flow_width),
@$diff;
Slic3r::debugf " %d thin walls detected\n", scalar(@{$self->thin_walls}) if @{$self->thin_walls};
}
if (0) {
require "Slic3r/SVG.pm";
Slic3r::SVG::output(undef, "surfaces.svg",
polygons => [ map $_->contour, @{$self->slices} ],
red_polygons => [ map $_->p, map @{$_->holes}, @{$self->slices} ],
);
}
}
sub prepare_fill_surfaces {
my $self = shift;
my @surfaces = @{$self->surfaces};
# merge too small internal surfaces with their surrounding tops
# (if they're too small, they can be treated as solid)
{
my $min_area = ((7 * $Slic3r::flow_spacing / $Slic3r::resolution)**2) * PI;
my $small_internal = [
grep { $_->expolygon->contour->area <= $min_area }
grep { $_->surface_type eq 'internal' }
@surfaces
];
foreach my $s (@$small_internal) {
@surfaces = grep $_ ne $s, @surfaces;
}
my $union = union_ex([
(map $_->p, grep $_->surface_type eq 'top', @surfaces),
(map @$_, map $_->expolygon->safety_offset, @$small_internal),
]);
my @top = map Slic3r::Surface->new(expolygon => $_, surface_type => 'top'), @$union;
@surfaces = (grep($_->surface_type ne 'top', @surfaces), @top);
}
# remove top/bottom surfaces
if ($Slic3r::solid_layers == 0) {
@surfaces = grep $_->surface_type eq 'internal', @surfaces;
}
# remove internal surfaces
if ($Slic3r::fill_density == 0) {
@surfaces = grep $_->surface_type ne 'internal', @surfaces;
}
$self->fill_surfaces([@surfaces]);
}
sub remove_small_surfaces {
my $self = shift;
my $distance = scale $Slic3r::flow_spacing / 2;
my @surfaces = @{$self->fill_surfaces};
@{$self->fill_surfaces} = ();
foreach my $surface (@surfaces) {
# offset inwards
my @offsets = $surface->expolygon->offset_ex(-$distance);
# offset the results outwards again and merge the results
@offsets = map $_->offset_ex($distance), @offsets;
@offsets = @{ union_ex([ map @$_, @offsets ], undef, 1) };
push @{$self->fill_surfaces}, map Slic3r::Surface->new(
expolygon => $_,
surface_type => $surface->surface_type), @offsets;
}
Slic3r::debugf "identified %d small surfaces at layer %d\n",
(@surfaces - @{$self->fill_surfaces}), $self->id
if @{$self->fill_surfaces} != @surfaces;
# the difference between @surfaces and $self->fill_surfaces
# is what's too small; we add it back as solid infill
if ($Slic3r::fill_density > 0) {
my $diff = diff_ex(
[ map $_->p, @surfaces ],
[ map $_->p, @{$self->fill_surfaces} ],
);
push @{$self->fill_surfaces}, map Slic3r::Surface->new(
expolygon => $_,
surface_type => 'internal-solid'), @$diff;
}
}
sub remove_small_perimeters {
my $self = shift;
my @good_perimeters = grep $_->is_printable, @{$self->perimeters};
Slic3r::debugf "removed %d unprintable perimeters at layer %d\n",
(@{$self->perimeters} - @good_perimeters), $self->id
if @good_perimeters != @{$self->perimeters};
@{$self->perimeters} = @good_perimeters;
}
# make bridges printable
sub process_bridges {
my $self = shift;
# no bridges are possible if we have no internal surfaces
return if $Slic3r::fill_density == 0;
my @bridges = ();
# a bottom surface on a layer > 0 is either a bridge or a overhang
# or a combination of both; any top surface is a candidate for
# reverse bridge processing
my @solid_surfaces = grep {
($_->surface_type eq 'bottom' && $self->id > 0) || $_->surface_type eq 'top'
} @{$self->fill_surfaces} or return;
my @internal_surfaces = grep $_->surface_type =~ /internal/, @{$self->slices};
SURFACE: foreach my $surface (@solid_surfaces) {
my $expolygon = $surface->expolygon->safety_offset;
my $description = $surface->surface_type eq 'bottom' ? 'bridge/overhang' : 'reverse bridge';
# offset the contour and intersect it with the internal surfaces to discover
# which of them has contact with our bridge
my @supporting_surfaces = ();
my ($contour_offset) = $expolygon->contour->offset(scale $Slic3r::flow_spacing * sqrt(2));
foreach my $internal_surface (@internal_surfaces) {
my $intersection = intersection_ex([$contour_offset], [$internal_surface->p]);
if (@$intersection) {
push @supporting_surfaces, $internal_surface;
}
}
if (0) {
require "Slic3r/SVG.pm";
Slic3r::SVG::output(undef, "bridge_surfaces.svg",
green_polygons => [ map $_->p, @supporting_surfaces ],
red_polygons => [ @$expolygon ],
);
}
Slic3r::debugf "Found $description on layer %d with %d support(s)\n",
$self->id, scalar(@supporting_surfaces);
next SURFACE unless @supporting_surfaces;
my $bridge_angle = undef;
if ($surface->surface_type eq 'bottom') {
# detect optimal bridge angle
my $bridge_over_hole = 0;
my @edges = (); # edges are POLYLINES
foreach my $supporting_surface (@supporting_surfaces) {
my @surface_edges = map $_->clip_with_polygon($contour_offset),
($supporting_surface->contour, $supporting_surface->holes);
if (@supporting_surfaces == 1 && @surface_edges == 1
&& @{$supporting_surface->contour} == @{$surface_edges[0]}) {
$bridge_over_hole = 1;
}
push @edges, grep { @$_ } @surface_edges;
}
Slic3r::debugf " Bridge is supported on %d edge(s)\n", scalar(@edges);
Slic3r::debugf " and covers a hole\n" if $bridge_over_hole;
if (0) {
require "Slic3r/SVG.pm";
Slic3r::SVG::output(undef, "bridge_edges.svg",
polylines => [ map $_->p, @edges ],
);
}
if (@edges == 2) {
my @chords = map Slic3r::Line->new($_->[0], $_->[-1]), @edges;
my @midpoints = map $_->midpoint, @chords;
my $line_between_midpoints = Slic3r::Line->new(@midpoints);
$bridge_angle = rad2deg_dir($line_between_midpoints->direction);
} elsif (@edges == 1) {
my $line = Slic3r::Line->new($edges[0]->[0], $edges[0]->[-1]);
$bridge_angle = rad2deg_dir($line->direction);
} else {
my $center = bounding_box_center([ map @$_, @edges ]);
my $x = my $y = 0;
foreach my $point (map @$, @edges) {
my $line = Slic3r::Line->new($center, $point);
my $dir = $line->direction;
my $len = $line->length;
$x += cos($dir) * $len;
$y += sin($dir) * $len;
}
$bridge_angle = rad2deg_dir(atan2($y, $x));
}
Slic3r::debugf " Optimal infill angle of bridge on layer %d is %d degrees\n",
$self->id, $bridge_angle if defined $bridge_angle;
}
# now, extend our bridge by taking a portion of supporting surfaces
{
# offset the bridge by the specified amount of mm (minimum 3)
my $bridge_overlap = scale 3;
my ($bridge_offset) = $expolygon->contour->offset($bridge_overlap);
# calculate the new bridge
my $intersection = intersection_ex(
[ @$expolygon, map $_->p, @supporting_surfaces ],
[ $bridge_offset ],
);
push @bridges, map Slic3r::Surface->new(
expolygon => $_,
surface_type => $surface->surface_type,
bridge_angle => $bridge_angle,
), @$intersection;
}
}
# now we need to merge bridges to avoid overlapping
{
# build a list of unique bridge types
my @surface_groups = Slic3r::Surface->group(@bridges);
# merge bridges of the same type, removing any of the bridges already merged;
# the order of @surface_groups determines the priority between bridges having
# different surface_type or bridge_angle
@bridges = ();
foreach my $surfaces (@surface_groups) {
my $union = union_ex([ map $_->p, @$surfaces ]);
my $diff = diff_ex(
[ map @$_, @$union ],
[ map $_->p, @bridges ],
);
push @bridges, map Slic3r::Surface->new(
expolygon => $_,
surface_type => $surfaces->[0]->surface_type,
bridge_angle => $surfaces->[0]->bridge_angle,
), @$union;
}
}
# apply bridges to layer
{
my @surfaces = @{$self->fill_surfaces};
@{$self->fill_surfaces} = ();
# intersect layer surfaces with bridges to get actual bridges
foreach my $bridge (@bridges) {
my $actual_bridge = intersection_ex(
[ map $_->p, @surfaces ],
[ $bridge->p ],
);
push @{$self->fill_surfaces}, map Slic3r::Surface->new(
expolygon => $_,
surface_type => $bridge->surface_type,
bridge_angle => $bridge->bridge_angle,
), @$actual_bridge;
}
# difference between layer surfaces and bridges are the other surfaces
foreach my $group (Slic3r::Surface->group(@surfaces)) {
my $difference = diff_ex(
[ map $_->p, @$group ],
[ map $_->p, @bridges ],
);
push @{$self->fill_surfaces}, map Slic3r::Surface->new(
expolygon => $_,
surface_type => $group->[0]->surface_type), @$difference;
}
}
}
1;