Slic3r/t/bridges.t

use Test::More tests => 12;
use strict;
use warnings;

BEGIN {
    use FindBin;
    use lib "$FindBin::Bin/../lib";
}

use List::Util qw(first);
use Slic3r;
use Slic3r::Geometry qw(scale epsilon deg2rad rad2deg PI);
use Slic3r::Test;

my $full_test = sub {
    my ($bd) = @_;
    {
        my $test = sub {
            my ($bridge_size, $rotate, $expected_angle, $tolerance) = @_;
        
            my ($x, $y) = @$bridge_size;
            my $lower = Slic3r::ExPolygon->new(
                Slic3r::Polygon->new_scale([-2,-2], [$x+2,-2], [$x+2,$y+2], [-2,$y+2]),
                Slic3r::Polygon->new_scale([0,0], [0,$y], [$x,$y], [$x,0]),
            );
            $lower->translate(scale 20, scale 20); # avoid negative coordinates for easier SVG preview
            $lower->rotate(deg2rad($rotate), [$x/2,$y/2]);
            my $bridge = $lower->[1]->clone;
            $bridge->reverse;
            $bridge = Slic3r::ExPolygon->new($bridge);
            $bd->lower_slices([$lower]);
            
            ok check_angle($bd, $bridge, $expected_angle, $tolerance), 'correct bridge angle for O-shaped overhang';
        };
    
        $test->([20,10], 0, 0);
        $test->([10,20], 0, 90);
        $test->([20,10], 45, 135, 20);
        $test->([20,10], 135, 45, 20);
    }

    {
        my $bridge = Slic3r::ExPolygon->new(
            Slic3r::Polygon->new_scale([0,0], [20,0], [20,10], [0,10]),
        );
        my $lower = [
            Slic3r::ExPolygon->new(
                Slic3r::Polygon->new_scale([-2,0], [0,0], [0,10], [-2,10]),
            ),
        ];
        $_->translate(scale 20, scale 20) for $bridge, @$lower; # avoid negative coordinates for easier SVG preview
    
        $lower->[1] = $lower->[0]->clone;
        $lower->[1]->translate(scale 22, 0);
    
        $bd->lower_slices($lower);
        ok check_angle($bd, $bridge, 0), 'correct bridge angle for two-sided bridge';
    }

    {
        my $bridge = Slic3r::ExPolygon->new(
            Slic3r::Polygon->new_scale([0,0], [20,0], [10,10], [0,10]),
        );
        my $lower = [
            Slic3r::ExPolygon->new(
                Slic3r::Polygon->new_scale([0,0], [0,10], [10,10], [10,12], [-2,12], [-2,-2], [22,-2], [22,0]),
            ),
        ];
        $_->translate(scale 20, scale 20) for $bridge, @$lower; # avoid negative coordinates for easier SVG preview
    
        $bd->lower_slices($lower);
        ok check_angle($bd, $bridge, 135), 'correct bridge angle for C-shaped overhang';
    }
};

my $flow = Slic3r::Flow->new(width => 0.5, spacing => 0.45, nozzle_diameter => 0.5);
my $bd = Slic3r::Layer::BridgeDetector->new(
    lower_slices    => [],
    infill_flow     => $flow,
);

$full_test->($bd);

# infill flow larger than perimeter flow
$bd->infill_flow(Slic3r::Flow->new(width => 0.9, spacing => 0.85, nozzle_diameter => 0.5));
$full_test->($bd);


sub check_angle {
    my ($bd, $bridge, $expected, $tolerance) = @_;
    
    $tolerance //= rad2deg($bd->resolution) + epsilon;
    my $result = $bd->detect_angle($bridge);
    
    # our epsilon is equal to the steps used by the bridge detection algorithm
    ###use XXX; YYY [ rad2deg($result), $expected ];
    return defined $result && abs(rad2deg($result) - $expected) < $tolerance;
}

__END__