572 lines
19 KiB
Perl
572 lines
19 KiB
Perl
package Slic3r::TriangleMesh;
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use Moo;
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use List::Util qw(reduce min max first);
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use Slic3r::Geometry qw(X Y Z A B unscale same_point);
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use Slic3r::Geometry::Clipper qw(union_ex offset);
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use Storable;
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# public
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has 'vertices' => (is => 'ro', required => 1); # id => [$x,$y,$z]
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has 'facets' => (is => 'ro', required => 1); # id => [ $v1_id, $v2_id, $v3_id ]
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# private
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has 'edges' => (is => 'rw'); # id => [ $v1_id, $v2_id ]
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has 'facets_edges' => (is => 'rw'); # id => [ $e1_id, $e2_id, $e3_id ]
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has 'edges_facets' => (is => 'rw'); # id => [ $f1_id, $f2_id, (...) ]
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use constant MIN => 0;
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use constant MAX => 1;
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use constant I_FMT => 'ffffllllc';
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use constant I_A => 0;
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use constant I_B => 1;
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use constant I_A_ID => 2;
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use constant I_B_ID => 3;
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use constant I_EDGE_A_ID => 4;
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use constant I_EDGE_B_ID => 5;
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use constant I_FACET_EDGE => 6;
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use constant FE_TOP => 0;
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use constant FE_BOTTOM => 1;
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sub analyze {
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my $self = shift;
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return if defined $self->edges;
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$self->edges([]);
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$self->facets_edges([]);
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$self->edges_facets([]);
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my %table = (); # edge_coordinates => edge_id
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my $vertices = $self->vertices; # save method calls
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for (my $facet_id = 0; $facet_id <= $#{$self->facets}; $facet_id++) {
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my $facet = $self->facets->[$facet_id];
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$self->facets_edges->[$facet_id] = [];
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# reorder vertices so that the first one is the one with lowest Z
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# this is needed to get all intersection lines in a consistent order
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# (external on the right of the line)
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{
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my $lowest_vertex_idx = reduce {
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$vertices->[ $facet->[$a] ][Z] < $vertices->[ $facet->[$b] ][Z] ? $a : $b
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} -3 .. -1;
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@$facet[-3..-1] = (@$facet[$lowest_vertex_idx..-1], @$facet[-3..($lowest_vertex_idx-1)]);
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}
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# ignore the normal if provided
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my @vertices = @$facet[-3..-1];
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foreach my $edge ($self->_facet_edges($facet_id)) {
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my $edge_coordinates = join ';', sort @$edge;
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my $edge_id = $table{$edge_coordinates};
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if (!defined $edge_id) {
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# Note that the order of vertices in $self->edges is *casual* because it is only
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# good for one of the two adjacent facets. For this reason, it must not be used
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# when dealing with single facets.
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push @{$self->edges}, $edge;
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$edge_id = $#{$self->edges};
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$table{$edge_coordinates} = $edge_id;
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$self->edges_facets->[$edge_id] = [];
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}
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push @{$self->facets_edges->[$facet_id]}, $edge_id;
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push @{$self->edges_facets->[$edge_id]}, $facet_id;
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}
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}
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}
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sub merge {
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my $class = shift;
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my @meshes = @_;
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my $vertices = [];
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my $facets = [];
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foreach my $mesh (@meshes) {
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my $v_offset = @$vertices;
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push @$vertices, @{$mesh->vertices};
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push @$facets, map {
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my $f = [@$_];
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$f->[$_] += $v_offset for -3..-1;
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$f;
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} @{$mesh->facets};
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}
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return $class->new(vertices => $vertices, facets => $facets);
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}
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sub clone {
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Storable::dclone($_[0])
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}
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sub _facet_edges {
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my $self = shift;
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my ($facet_id) = @_;
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my $facet = $self->facets->[$facet_id];
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return (
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[ $facet->[-3], $facet->[-2] ],
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[ $facet->[-2], $facet->[-1] ],
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[ $facet->[-1], $facet->[-3] ],
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);
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}
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# This method is supposed to remove narrow triangles, but it actually doesn't
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# work much; I'm committing it for future reference but I'm going to remove it later.
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# Note: a 'clean' method should actually take care of non-manifold facets and remove
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# them.
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sub clean {
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my $self = shift;
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# retrieve all edges shared by more than two facets;
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my @weird_edges = grep { @{$self->edge_facets->{$_}} != 2 } keys %{$self->edge_facets};
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# usually most of these facets are very narrow triangles whose two edges
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# are detected as collapsed, and thus added twice to the edge in edge_fasets table
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# let's identify these triangles
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my @narrow_facets_indexes = ();
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foreach my $edge_id (@weird_edges) {
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my %facet_count = ();
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$facet_count{$_}++ for @{$self->edge_facets->{$edge_id}};
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@{$self->edge_facets->{$edge_id}} = grep $facet_count{$_} == 1, keys %facet_count;
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push @narrow_facets_indexes, grep $facet_count{$_} > 1, keys %facet_count;
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}
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# remove identified narrow facets
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foreach my $facet_id (@narrow_facets_indexes) {last;
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splice @{$self->facets}, $facet_id, 1;
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splice @{$self->facets_edges}, $facet_id, 1;
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foreach my $facet_ides (values %{$self->edge_facets}) {
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@$facet_ides = map { $_ > $facet_id ? ($_-1) : $_ } @$facet_ides;
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}
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}
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Slic3r::debugf "%d narrow facets removed\n", scalar(@narrow_facets_indexes)
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if @narrow_facets_indexes;
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}
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sub check_manifoldness {
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my $self = shift;
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$self->analyze;
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# look for any edges belonging to an odd number of facets
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# we should actually check that each pair of facets belonging to this edge
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# has compatible winding order
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my ($first_bad_edge_id) =
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grep { @{ $self->edges_facets->[$_] } % 2 } 0..$#{$self->edges_facets};
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if (defined $first_bad_edge_id) {
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warn sprintf "Warning: The input file contains a hole near edge %f,%f,%f-%f,%f,%f (not manifold). "
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. "You might want to repair it and retry, or to check the resulting G-code before printing anyway.\n",
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map @{$self->vertices->[$_]}, @{$self->edges->[$first_bad_edge_id]};
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return 0;
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}
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# empty the edges array as we don't really need it anymore
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@{$self->edges} = ();
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return 1;
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}
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sub unpack_line {
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my ($packed) = @_;
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my $data = [ unpack I_FMT, $packed ];
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splice @$data, 0, 4, [ @$data[0,1] ], [ @$data[2,3] ];
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$data->[$_] = undef for grep $data->[$_] == -1, I_A_ID, I_B_ID, I_EDGE_A_ID, I_EDGE_B_ID, I_FACET_EDGE;
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return $data;
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}
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sub make_loops {
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my ($lines) = @_;
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my @lines = map unpack_line($_), @$lines;
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# remove tangent edges
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for my $i (0 .. $#lines) {
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next unless defined $lines[$i] && defined $lines[$i][I_FACET_EDGE];
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# if the line is a facet edge, find another facet edge
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# having the same endpoints but in reverse order
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for my $j ($i+1 .. $#lines) {
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next unless defined $lines[$j] && defined $lines[$j][I_FACET_EDGE];
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# are these facets adjacent? (sharing a common edge on this layer)
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if ($lines[$i][I_A_ID] == $lines[$j][I_A_ID] && $lines[$i][I_B_ID] == $lines[$j][I_B_ID]) {
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# if they are both oriented upwards or downwards (like a 'V')
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# then we can remove both edges from this layer since it won't
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# affect the sliced shape
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if ($lines[$j][I_FACET_EDGE] == $lines[$i][I_FACET_EDGE]) {
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$lines[$i] = undef;
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$lines[$j] = undef;
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last;
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}
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# if one of them is oriented upwards and the other is oriented
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# downwards, let's only keep one of them (it doesn't matter which
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# one since all 'top' lines were reversed at slicing)
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if ($lines[$i][I_FACET_EDGE] != $lines[$j][I_FACET_EDGE]) {
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$lines[$j] = undef;
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last;
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}
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}
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}
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}
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@lines = grep $_, @lines;
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# build a map of lines by EDGE_A_ID and A_ID
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my %by_edge_a_id = my %by_a_id = ();
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for (0..$#lines) {
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if (defined(my $edge_a_id = $lines[$_][I_EDGE_A_ID])) {
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$by_edge_a_id{$edge_a_id} //= [];
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push @{ $by_edge_a_id{$edge_a_id} }, $_;
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}
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if (defined(my $a_id = $lines[$_][I_A_ID])) {
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$by_a_id{$a_id} //= [];
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push @{ $by_a_id{$a_id} }, $_;
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}
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}
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my (@polygons, @failed_loops) = ();
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my %used_lines = ();
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CYCLE: while (1) {
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# take first spare line and start a new loop
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my $first_idx = first { !exists $used_lines{$_} } 0..$#lines;
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last if !defined $first_idx;
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$used_lines{$first_idx} = 1;
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my @loop = ($lines[$first_idx]);
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while (1) {
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# find a line starting where last one finishes
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my $line_idx;
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$line_idx = first { !exists $used_lines{$_} } @{ $by_edge_a_id{$loop[-1][I_EDGE_B_ID]} // [] }
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if defined $loop[-1][I_EDGE_B_ID];
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$line_idx //= first { !exists $used_lines{$_} } @{ $by_a_id{$loop[-1][I_B_ID]} // [] }
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if defined $loop[-1][I_B_ID];
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if (!defined $line_idx) {
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# check whether we closed this loop
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if ((defined $loop[0][I_EDGE_A_ID] && defined $loop[-1][I_EDGE_B_ID] && $loop[0][I_EDGE_A_ID] == $loop[-1][I_EDGE_B_ID])
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|| (defined $loop[0][I_A_ID] && defined $loop[-1][I_B_ID] && $loop[0][I_A_ID] == $loop[-1][I_B_ID])) {
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# loop is complete!
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push @polygons, Slic3r::Polygon->new(map $_->[I_A], @loop);
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Slic3r::debugf " Discovered %s polygon of %d points\n",
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($polygons[-1]->is_counter_clockwise ? 'ccw' : 'cw'), scalar(@{$polygons[-1]})
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if $Slic3r::debug;
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next CYCLE;
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}
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# we can't close this loop!
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push @failed_loops, [@loop];
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next CYCLE;
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}
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push @loop, $lines[$line_idx];
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$used_lines{$line_idx} = 1;
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}
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}
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# TODO: we should try to combine failed loops
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for my $loop (grep @$_ >= 3, @failed_loops) {
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push @polygons, Slic3r::Polygon->new(map $_->[I_A], @$loop);
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Slic3r::debugf " Discovered failed %s polygon of %d points\n",
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($polygons[-1]->is_counter_clockwise ? 'ccw' : 'cw'), scalar(@$loop)
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if $Slic3r::debug;
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}
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return (@failed_loops ? 1 : 0, [@polygons]);
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}
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sub rotate {
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my $self = shift;
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my ($deg, $center) = @_;
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return if $deg == 0;
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my $rad = Slic3r::Geometry::deg2rad($deg);
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# transform vertex coordinates
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foreach my $vertex (@{$self->vertices}) {
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@$vertex = (@{ +(Slic3r::Geometry::rotate_points($rad, $center, [ $vertex->[X], $vertex->[Y] ]))[0] }, $vertex->[Z]);
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}
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}
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sub scale {
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my $self = shift;
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my ($factor) = @_;
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return if $factor == 1;
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# transform vertex coordinates
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foreach my $vertex (@{$self->vertices}) {
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$vertex->[$_] *= $factor for X,Y,Z;
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}
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}
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sub scale_xyz {
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my $self = shift;
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my ($versor) = @_;
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# transform vertex coordinates
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foreach my $vertex (@{$self->vertices}) {
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$vertex->[$_] *= $versor->[$_] for X,Y,Z;
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}
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}
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sub move {
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my $self = shift;
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my (@shift) = @_;
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# transform vertex coordinates
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foreach my $vertex (@{$self->vertices}) {
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$vertex->[$_] += $shift[$_] || 0 for X,Y,Z;
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}
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}
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sub align_to_origin {
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my $self = shift;
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# calculate the displacements needed to
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# have lowest value for each axis at coordinate 0
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my $bb = $self->bounding_box;
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$self->move(map -$bb->extents->[$_][MIN], X,Y,Z);
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}
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sub center_around_origin {
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my $self = shift;
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$self->move(map -$_, @{ $self->center });
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}
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sub center {
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my $self = shift;
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return $self->bounding_box->center;
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}
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sub duplicate {
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my $self = shift;
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my (@shifts) = @_;
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my @new_facets = ();
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foreach my $facet (@{$self->facets}) {
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# transform vertex coordinates
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my ($normal, @vertices) = @$facet;
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foreach my $shift (@shifts) {
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push @new_facets, [ $normal ];
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foreach my $vertex (@vertices) {
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push @{$self->vertices}, [ map $self->vertices->[$vertex][$_] + ($shift->[$_] || 0), (X,Y,Z) ];
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push @{$new_facets[-1]}, $#{$self->vertices};
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}
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}
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}
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push @{$self->facets}, @new_facets;
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$self->BUILD;
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}
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sub used_vertices {
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my $self = shift;
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return [ map $self->vertices->[$_], map @$_, @{$self->facets} ];
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}
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sub bounding_box {
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my $self = shift;
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return Slic3r::Geometry::BoundingBox->new_from_points_3D($self->used_vertices);
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}
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sub size {
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my $self = shift;
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return $self->bounding_box->size;
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}
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sub slice_facet {
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my $self = shift;
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my ($print_object, $facet_id) = @_;
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my @vertices = @{$self->facets->[$facet_id]}[-3..-1];
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Slic3r::debugf "\n==> FACET %d (%f,%f,%f - %f,%f,%f - %f,%f,%f):\n",
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$facet_id, map @{$self->vertices->[$_]}, @vertices
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if $Slic3r::debug;
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# find the vertical extents of the facet
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my @z = map $_->[Z], @{$self->vertices}[@vertices];
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my $min_z = min(@z);
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my $max_z = max(@z);
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Slic3r::debugf "z: min = %.0f, max = %.0f\n", $min_z, $max_z
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if $Slic3r::debug;
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if ($max_z == $min_z) {
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Slic3r::debugf "Facet is horizontal; ignoring\n";
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return;
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}
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# calculate the layer extents
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my ($min_layer, $max_layer) = $print_object->get_layer_range($min_z, $max_z);
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Slic3r::debugf "layers: min = %s, max = %s\n", $min_layer, $max_layer
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if $Slic3r::debug;
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my $lines = {}; # layer_id => [ lines ]
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for my $layer_id ($min_layer .. $max_layer) {
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my $layer = $print_object->layers->[$layer_id];
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$lines->{$layer_id} ||= [];
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push @{ $lines->{$layer_id} }, $self->intersect_facet($facet_id, $layer->slice_z);
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}
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return $lines;
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}
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sub intersect_facet {
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my $self = shift;
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my ($facet_id, $z) = @_;
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my @vertices_ids = @{$self->facets->[$facet_id]}[-3..-1];
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my %vertices = map { $_ => $self->vertices->[$_] } @vertices_ids; # cache vertices
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my @edge_ids = @{$self->facets_edges->[$facet_id]};
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my @edge_vertices_ids = $self->_facet_edges($facet_id);
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my (@points, @intersection_points, @points_on_layer) = ();
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for my $e (0..2) {
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my ($a_id, $b_id) = @{$edge_vertices_ids[$e]};
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my ($a, $b) = @vertices{$a_id, $b_id};
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#printf "Az = %f, Bz = %f, z = %f\n", $a->[Z], $b->[Z], $z;
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if ($a->[Z] == $b->[Z] && $a->[Z] == $z) {
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# edge is horizontal and belongs to the current layer
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my $edge_type = (grep $vertices{$_}[Z] < $z, @vertices_ids) ? FE_TOP : FE_BOTTOM;
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if ($edge_type == FE_TOP) {
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($a, $b) = ($b, $a);
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($a_id, $b_id) = ($b_id, $a_id);
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}
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# We assume that this method is never being called for horizontal
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# facets, so no other edge is going to be on this layer.
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return pack I_FMT, (
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$a->[X], $a->[Y], # I_A
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$b->[X], $b->[Y], # I_B
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$a_id, # I_A_ID
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$b_id, # I_B_ID
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-1, # I_EDGE_A_ID
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-1, # I_EDGE_B_ID
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$edge_type, # I_FACET_EDGE
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);
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#print "Horizontal edge at $z!\n";
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} elsif ($a->[Z] == $z) {
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#print "A point on plane $z!\n";
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push @points, [ $a->[X], $a->[Y], $a_id ];
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push @points_on_layer, $#points;
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} elsif ($b->[Z] == $z) {
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#print "B point on plane $z!\n";
|
||
push @points, [ $b->[X], $b->[Y], $b_id ];
|
||
push @points_on_layer, $#points;
|
||
|
||
} elsif (($a->[Z] < $z && $b->[Z] > $z) || ($b->[Z] < $z && $a->[Z] > $z)) {
|
||
# edge intersects the current layer; calculate intersection
|
||
push @points, [
|
||
$b->[X] + ($a->[X] - $b->[X]) * ($z - $b->[Z]) / ($a->[Z] - $b->[Z]),
|
||
$b->[Y] + ($a->[Y] - $b->[Y]) * ($z - $b->[Z]) / ($a->[Z] - $b->[Z]),
|
||
undef,
|
||
$edge_ids[$e],
|
||
];
|
||
push @intersection_points, $#points;
|
||
#print "Intersects at $z!\n";
|
||
}
|
||
}
|
||
|
||
if (@points_on_layer == 2) {
|
||
if (@intersection_points == 1) {
|
||
splice @points, $points_on_layer[1], 1;
|
||
} elsif (@intersection_points == 0) {
|
||
return if same_point(@points[@points_on_layer]);
|
||
}
|
||
}
|
||
|
||
if (@points) {
|
||
# defensive programming:
|
||
die "Facets must intersect each plane 0 or 2 times" if @points != 2;
|
||
|
||
return pack I_FMT, (
|
||
$points[B][X], $points[B][Y], # I_A
|
||
$points[A][X], $points[A][Y], # I_B
|
||
$points[B][2] // -1, # I_A_ID /
|
||
$points[A][2] // -1, # I_B_ID /
|
||
$points[B][3] // -1, # I_EDGE_A_ID /
|
||
$points[A][3] // -1, # I_EDGE_B_ID /
|
||
-1, # I_FACET_EDGE
|
||
);
|
||
#printf " intersection points at z = %f: %f,%f - %f,%f\n", $z, map @$_, @intersection_points;
|
||
}
|
||
|
||
return ();
|
||
}
|
||
|
||
sub get_connected_facets {
|
||
my $self = shift;
|
||
my ($facet_id) = @_;
|
||
|
||
my %facets = ();
|
||
foreach my $edge_id (@{$self->facets_edges->[$facet_id]}) {
|
||
$facets{$_} = 1 for @{$self->edges_facets->[$edge_id]};
|
||
}
|
||
delete $facets{$facet_id};
|
||
return keys %facets;
|
||
}
|
||
|
||
sub split_mesh {
|
||
my $self = shift;
|
||
|
||
$self->analyze;
|
||
|
||
my @meshes = ();
|
||
|
||
# loop while we have remaining facets
|
||
while (1) {
|
||
# get the first facet
|
||
my @facet_queue = ();
|
||
my @facets = ();
|
||
for (my $i = 0; $i <= $#{$self->facets}; $i++) {
|
||
if (defined $self->facets->[$i]) {
|
||
push @facet_queue, $i;
|
||
last;
|
||
}
|
||
}
|
||
last if !@facet_queue;
|
||
|
||
while (defined (my $facet_id = shift @facet_queue)) {
|
||
next unless defined $self->facets->[$facet_id];
|
||
push @facets, map [ @$_ ], $self->facets->[$facet_id];
|
||
push @facet_queue, $self->get_connected_facets($facet_id);
|
||
$self->facets->[$facet_id] = undef;
|
||
}
|
||
|
||
my %vertices = map { $_ => 1 } map @$_[-3..-1], @facets;
|
||
my @new_vertices = keys %vertices;
|
||
my %new_vertices = map { $new_vertices[$_] => $_ } 0..$#new_vertices;
|
||
foreach my $facet (@facets) {
|
||
$facet->[$_] = $new_vertices{$facet->[$_]} for -3..-1;
|
||
}
|
||
push @meshes, Slic3r::TriangleMesh->new(
|
||
facets => \@facets,
|
||
vertices => [ map $self->vertices->[$_], keys %vertices ],
|
||
);
|
||
}
|
||
|
||
return @meshes;
|
||
}
|
||
|
||
# this will return *scaled* expolygons, so it is expected to be run
|
||
# on unscaled meshes
|
||
sub horizontal_projection {
|
||
my $self = shift;
|
||
|
||
my @f = ();
|
||
foreach my $facet (@{$self->facets}) {
|
||
push @f, Slic3r::Polygon->new(
|
||
map [ map $_ / &Slic3r::SCALING_FACTOR, @{$self->vertices->[$_]}[X,Y] ], @$facet
|
||
);
|
||
}
|
||
|
||
$_->make_counter_clockwise for @f; # do this after scaling, as winding order might change while doing that
|
||
|
||
# the offset factor was tuned using groovemount.stl
|
||
return union_ex([ offset(\@f, Slic3r::Geometry::scale 0.01) ], 1);
|
||
}
|
||
|
||
1;
|