PrusaSlicer-NonPlainar/lib/Slic3r/Format/STL.pm

151 lines
4.0 KiB
Perl

package Slic3r::Format::STL;
use Moo;
use Slic3r::Geometry qw(X Y Z triangle_normal);
sub read_file {
my $self = shift;
my ($file) = @_;
Slic3r::open(\my $fh, '<', $file) or die "Failed to open $file\n";
# let's detect whether file is ASCII or binary
my $mode;
{
my $size = +(stat $fh)[7];
$mode = 'ascii' if $size < 80 + 4;
# skip binary header
seek $fh, 80, 0;
read $fh, my $buf, 4;
my $triangle_count = unpack 'L', $buf;
die "STL file seems invalid, could not read facet count\n" if !defined $triangle_count;
my $expected_size =
+ 80 # header
+ 4 # count
+ $triangle_count * (
+ 4 # normal, pt,pt,pt (vectors)
* 4 # bytes per value
* 3 # values per vector
+ 2 # the trailing 'short'
);
$mode = ($size == $expected_size) ? 'binary' : 'ascii';
}
my $facets = [];
$mode eq 'ascii'
? _read_ascii($fh, $facets)
: _read_binary($fh, $facets);
close $fh;
my $vertices = [];
{
my %vertices_map = (); # given a vertex's coordinates, what's its index?
for (my $f = 0; $f <= $#$facets; $f++) {
for (-3..-1) {
my $point_id = join ',', @{$facets->[$f][$_]};
if (exists $vertices_map{$point_id}) {
$facets->[$f][$_] = $vertices_map{$point_id};
} else {
push @$vertices, $facets->[$f][$_];
$facets->[$f][$_] = $vertices_map{$point_id} = $#$vertices;
}
}
}
}
my $model = Slic3r::Model->new;
my $object = $model->add_object(vertices => $vertices);
my $volume = $object->add_volume(facets => $facets);
return $model;
}
sub _read_ascii {
my ($fh, $facets) = @_;
my $point_re = qr/([^ ]+)\s+([^ ]+)\s+([^ ]+)/;
my $facet;
seek $fh, 0, 0;
while (my $_ = <$fh>) {
if (!$facet) {
/^\s*facet\s+normal\s+$point_re/ or next;
$facet = []; # ignore normal: [$1, $2, $3]
} else {
if (/^\s*endfacet/) {
push @$facets, $facet;
undef $facet;
} else {
/^\s*vertex\s+$point_re/o or next;
push @$facet, [map $_ * 1, $1, $2, $3];
}
}
}
if ($facet) {
die "STL file seems invalid\n";
}
}
sub _read_binary {
my ($fh, $facets) = @_;
die "bigfloat" unless length(pack "f", 1) == 4;
binmode $fh;
seek $fh, 80 + 4, 0;
while (read $fh, my $_, 4*4*3+2) {
my @v = unpack '(f<3)4';
push @$facets, [ [@v[3..5]], [@v[6..8]], [@v[9..11]] ]; # ignore normal: [@v[0..2]]
}
}
sub write_file {
my $self = shift;
my ($file, $model, %params) = @_;
Slic3r::open(\my $fh, '>', $file);
$params{binary}
? _write_binary($fh, $model->mesh)
: _write_ascii($fh, $model->mesh);
close $fh;
}
sub _write_binary {
my ($fh, $mesh) = @_;
die "bigfloat" unless length(pack "f", 1) == 4;
binmode $fh;
print $fh pack 'x80';
print $fh pack 'L', scalar(@{$mesh->facets});
foreach my $facet (@{$mesh->facets}) {
print $fh pack '(f<3)4S',
@{_facet_normal($mesh, $facet)},
(map @{$mesh->vertices->[$_]}, @$facet[-3..-1]),
0;
}
}
sub _write_ascii {
my ($fh, $mesh) = @_;
printf $fh "solid\n";
foreach my $facet (@{$mesh->facets}) {
printf $fh " facet normal %f %f %f\n", @{_facet_normal($mesh, $facet)};
printf $fh " outer loop\n";
printf $fh " vertex %f %f %f\n", @{$mesh->vertices->[$_]} for @$facet[-3..-1];
printf $fh " endloop\n";
printf $fh " endfacet\n";
}
printf $fh "endsolid\n";
}
sub _facet_normal {
my ($mesh, $facet) = @_;
return triangle_normal(map $mesh->vertices->[$_], @$facet[-3..-1]);
}
1;