More tests and related fixes to bridge detection. #1917

This commit is contained in:
Alessandro Ranellucci 2014-04-21 20:44:21 +02:00
parent c4bfe64fb8
commit f7e8a99078
3 changed files with 50 additions and 30 deletions

View file

@ -1,19 +1,20 @@
package Slic3r::Layer::BridgeDetector;
use Moo;
use List::Util qw(first sum);
use Slic3r::Geometry qw(PI scaled_epsilon rad2deg epsilon);
use List::Util qw(first sum max);
use Slic3r::Geometry qw(PI unscale scaled_epsilon rad2deg epsilon);
use Slic3r::Geometry::Clipper qw(intersection_pl intersection_ex);
has 'lower_slices' => (is => 'rw', required => 1); # ExPolygons or ExPolygonCollection
has 'perimeter_flow' => (is => 'rw', required => 1);
has 'infill_flow' => (is => 'rw', required => 1);
has 'resolution' => (is => 'rw', default => sub { PI/36 });
sub detect_angle {
my ($self, $expolygon) = @_;
my $grown = $expolygon->offset(+$self->perimeter_flow->scaled_width);
my $anchors_offset = $self->infill_flow->scaled_width;
my $grown = $expolygon->offset(+$anchors_offset);
my @lower = @{$self->lower_slices}; # expolygons
# detect what edges lie on lower slices
@ -55,8 +56,10 @@ sub detect_angle {
$bridge_angle = $line->direction;
}
} elsif (@edges) {
# inset the bridge expolygon; we'll use this one to clip our test lines
my $inset = $expolygon->offset_ex($self->infill_flow->scaled_width);
# Outset the bridge expolygon by half the amount we used for detecting anchors;
# we'll use this one to clip our test lines and be sure that their endpoints
# are inside the anchors and not on their contours leading to false negatives.
my $clip_area = $expolygon->offset_ex(+$anchors_offset/2);
# detect anchors as intersection between our bridge expolygon and the lower slices
my $anchors = intersection_ex(
@ -69,14 +72,15 @@ sub detect_angle {
# 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 %directions_coverage = (); # angle => score
my %directions_avg_length = (); # angle => score
my $line_increment = $self->infill_flow->scaled_width;
for (my $angle = 0; $angle < PI; $angle += $self->resolution) {
my $my_inset = [ map $_->clone, @$inset ];
my $my_anchors = [ map $_->clone, @$anchors ];
my $my_clip_area = [ map $_->clone, @$clip_area ];
my $my_anchors = [ map $_->clone, @$anchors ];
# rotate everything - the center point doesn't matter
$_->rotate($angle, [0,0]) for @$my_inset, @$my_anchors;
$_->rotate($angle, [0,0]) for @$my_clip_area, @$my_anchors;
# generate lines in this direction
my $bounding_box = Slic3r::Geometry::BoundingBox->new_from_points([ map @$_, map @$_, @$my_anchors ]);
@ -89,8 +93,8 @@ sub detect_angle {
);
}
my @clipped_lines = map Slic3r::Line->new(@$_), @{ intersection_pl(\@lines, [ map @$_, @$my_inset ]) };
my @clipped_lines = map Slic3r::Line->new(@$_), @{ intersection_pl(\@lines, [ map @$_, @$my_clip_area ]) };
# 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
@ -99,15 +103,29 @@ sub detect_angle {
(first { $_->contains_point($line->a) } @$my_anchors)
&& (first { $_->contains_point($line->b) } @$my_anchors);
} @clipped_lines;
my @lengths = map $_->length, @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;
$directions_coverage{$angle} = sum(@lengths) // 0;
# max length of bridged lines
$directions_avg_length{$angle} = @lengths ? (max(@lengths)) : -1;
}
# the best direction is the one causing most lines to be bridged (thus most coverage)
# and shortest max line length
my @sorted_directions = sort {
my $cmp;
my $coverage_diff = $directions_coverage{$a} - $directions_coverage{$b};
if (abs($coverage_diff) < $self->infill_flow->scaled_width) {
$cmp = $directions_avg_length{$b} <=> $directions_avg_length{$a};
} else {
$cmp = ($coverage_diff > 0) ? 1 : -1;
}
$cmp;
} keys %directions_coverage;
# the best direction is the one causing most lines to be bridged
$bridge_angle = $sorted_directions[-1];
}
}