PrusaSlicer-NonPlainar/lib/Slic3r/ExPolygon.pm
2013-01-28 00:32:19 +01:00

339 lines
8.8 KiB
Perl

package Slic3r::ExPolygon;
use strict;
use warnings;
# an ExPolygon is a polygon with holes
use Boost::Geometry::Utils;
use Math::Geometry::Voronoi;
use Slic3r::Geometry qw(X Y A B point_in_polygon same_line line_length epsilon);
use Slic3r::Geometry::Clipper qw(union_ex JT_MITER);
# the constructor accepts an array of polygons
# or a Math::Clipper ExPolygon (hashref)
sub new {
my $class = shift;
my $self;
if (@_ == 1 && ref $_[0] eq 'HASH') {
$self = [
Slic3r::Polygon->new($_[0]{outer}),
map Slic3r::Polygon->new($_), @{$_[0]{holes}},
];
} else {
$self = [ map Slic3r::Polygon->new($_), @_ ];
}
bless $self, $class;
$self;
}
sub clone {
my $self = shift;
return (ref $self)->new(map $_->clone, @$self);
}
sub contour {
my $self = shift;
return $self->[0];
}
sub holes {
my $self = shift;
return @$self[1..$#$self];
}
sub lines {
my $self = shift;
return map $_->lines, @$self;
}
sub clipper_expolygon {
my $self = shift;
return {
outer => $self->contour,
holes => [ $self->holes ],
};
}
sub boost_polygon {
my $self = shift;
return Boost::Geometry::Utils::polygon(@$self);
}
sub offset {
my $self = shift;
return Slic3r::Geometry::Clipper::offset($self, @_);
}
sub offset_ex {
my $self = shift;
return Slic3r::Geometry::Clipper::offset_ex($self, @_);
}
sub safety_offset {
my $self = shift;
# we're offsetting contour and holes separately
# because Clipper doesn't return polygons in the same order as
# we feed them to it
return (ref $self)->new(
$self->contour->safety_offset,
@{ Slic3r::Geometry::Clipper::safety_offset([$self->holes]) },
);
}
sub noncollapsing_offset_ex {
my $self = shift;
my ($distance, @params) = @_;
return $self->offset_ex($distance + 1, @params);
}
sub encloses_point {
my $self = shift;
my ($point) = @_;
return $self->contour->encloses_point($point)
&& (!grep($_->encloses_point($point), $self->holes)
|| grep($_->point_on_segment($point), $self->holes));
}
# A version of encloses_point for use when hole borders do not matter.
# Useful because point_on_segment is slow
sub encloses_point_quick {
my $self = shift;
my ($point) = @_;
return $self->contour->encloses_point($point)
&& !grep($_->encloses_point($point), $self->holes);
}
sub encloses_line {
my $self = shift;
my ($line, $tolerance) = @_;
my $clip = $self->clip_line($line);
if (!defined $tolerance) {
# optimization
return @$clip == 1 && same_line($clip->[0], $line);
} else {
return @$clip == 1 && abs(line_length($clip->[0]) - $line->length) < $tolerance;
}
}
sub point_on_segment {
my $self = shift;
my ($point) = @_;
for (@$self) {
my $line = $_->point_on_segment($point);
return $line if $line;
}
return undef;
}
sub bounding_box {
my $self = shift;
return Slic3r::Geometry::bounding_box($self->contour);
}
sub bounding_box_polygon {
my $self = shift;
my @bb = $self->bounding_box;
return Slic3r::Polygon->new([
[ $bb[0], $bb[1] ],
[ $bb[2], $bb[1] ],
[ $bb[2], $bb[3] ],
[ $bb[0], $bb[3] ],
]);
}
sub bounding_box_center {
my $self = shift;
return Slic3r::Geometry::bounding_box_center($self->contour);
}
sub clip_line {
my $self = shift;
my ($line) = @_; # line must be a Slic3r::Line object
return Boost::Geometry::Utils::polygon_multi_linestring_intersection($self, [$line]);
}
sub simplify {
my $self = shift;
$_->simplify(@_) for @$self;
$self;
}
sub scale {
my $self = shift;
$_->scale(@_) for @$self;
}
sub translate {
my $self = shift;
$_->translate(@_) for @$self;
$self;
}
sub rotate {
my $self = shift;
$_->rotate(@_) for @$self;
$self;
}
sub area {
my $self = shift;
my $area = $self->contour->area;
$area -= $_->area for $self->holes;
return $area;
}
# this method only works for expolygons having only a contour or
# a contour and a hole, and not being thicker than the supplied
# width. it returns a polyline or a polygon
sub medial_axis {
my $self = shift;
my ($width) = @_;
my @self_lines = map $_->lines, @$self;
my $expolygon = $self->clone;
my @points = ();
foreach my $polygon (@$expolygon) {
Slic3r::Geometry::polyline_remove_short_segments($polygon, $width / 2);
# subdivide polygon segments so that we don't have anyone of them
# being longer than $width / 2
$polygon->subdivide($width/2);
push @points, @$polygon;
}
my $voronoi = Math::Geometry::Voronoi->new(points => \@points);
$voronoi->compute;
my @skeleton_lines = ();
my $vertices = $voronoi->vertices;
my $edges = $voronoi->edges;
foreach my $edge (@$edges) {
# ignore lines going to infinite
next if $edge->[1] == -1 || $edge->[2] == -1;
my ($a, $b);
$a = $vertices->[$edge->[1]];
$b = $vertices->[$edge->[2]];
next if !$self->encloses_point_quick($a) || !$self->encloses_point_quick($b);
push @skeleton_lines, [$edge->[1], $edge->[2]];
}
# remove leafs (lines not connected to other lines at one of their endpoints)
{
my %pointmap = ();
$pointmap{$_}++ for map @$_, @skeleton_lines;
@skeleton_lines = grep {
$pointmap{$_->[A]} >= 2 && $pointmap{$_->[B]} >= 2
} @skeleton_lines;
}
return () if !@skeleton_lines;
# now walk along the medial axis and build continuos polylines or polygons
my @polylines = ();
{
# build a map of line endpoints
my %pointmap = (); # point_idx => [line_idx, line_idx ...]
for my $line_idx (0 .. $#skeleton_lines) {
for my $point_idx (@{$skeleton_lines[$line_idx]}) {
$pointmap{$point_idx} ||= [];
push @{$pointmap{$point_idx}}, $line_idx;
}
}
# build the list of available lines
my %spare_lines = map {$_ => 1} (0 .. $#skeleton_lines);
CYCLE: while (%spare_lines) {
push @polylines, [];
my $polyline = $polylines[-1];
# start from a random line
my $first_line_idx = +(keys %spare_lines)[0];
delete $spare_lines{$first_line_idx};
push @$polyline, @{ $skeleton_lines[$first_line_idx] };
while (1) {
my $last_point_id = $polyline->[-1];
my $lines_starting_here = $pointmap{$last_point_id};
# remove all the visited lines from the array
shift @$lines_starting_here
while @$lines_starting_here && !$spare_lines{$lines_starting_here->[0]};
# do we have a line starting here?
my $next_line_idx = shift @$lines_starting_here;
if (!defined $next_line_idx) {
delete $pointmap{$last_point_id};
next CYCLE;
}
# line is not available anymore
delete $spare_lines{$next_line_idx};
# add the other point to our polyline and continue walking
push @$polyline, grep $_ ne $last_point_id, @{$skeleton_lines[$next_line_idx]};
}
}
}
my @result = ();
foreach my $polyline (@polylines) {
next unless @$polyline >= 2;
# now replace point indexes with coordinates
@$polyline = map $vertices->[$_], @$polyline;
# cleanup
$polyline = Slic3r::Geometry::douglas_peucker($polyline, $width / 7);
if (Slic3r::Geometry::same_point($polyline->[0], $polyline->[-1])) {
next if @$polyline == 2;
push @result, Slic3r::Polygon->new(@$polyline[0..$#$polyline-1]);
} else {
push @result, Slic3r::Polyline->new($polyline);
}
}
return @result;
}
package Slic3r::ExPolygon::Collection;
use Moo;
use Slic3r::Geometry qw(X1 Y1);
has 'expolygons' => (is => 'ro', default => sub { [] });
sub clone {
my $self = shift;
return (ref $self)->new(
expolygons => [ map $_->clone, @{$self->expolygons} ],
);
}
sub align_to_origin {
my $self = shift;
my @bb = Slic3r::Geometry::bounding_box([ map @$_, map @$_, @{$self->expolygons} ]);
$_->translate(-$bb[X1], -$bb[Y1]) for @{$self->expolygons};
}
sub rotate {
my $self = shift;
$_->rotate(@_) for @{$self->expolygons};
}
sub size {
my $self = shift;
return [ Slic3r::Geometry::size_2D([ map @$_, map @$_, @{$self->expolygons} ]) ];
}
1;