New bridging logic, more robust. #58

This commit is contained in:
Alessandro Ranellucci 2011-11-19 16:08:00 +01:00
parent 1ef4d006a0
commit a1c766cc52
8 changed files with 86 additions and 75 deletions

View file

@ -356,83 +356,68 @@ sub process_bridges {
($_->surface_type eq 'bottom' && $self->id > 0) || $_->surface_type eq 'top'
} @{$self->surfaces} or return;
my @supporting_surfaces = grep $_->surface_type =~ /internal/, @{$self->surfaces};
my @internal_surfaces = grep $_->surface_type =~ /internal/, @{$self->surfaces};
SURFACE: foreach my $surface (@solid_surfaces) {
# ignore holes in bridges;
# offset the surface a bit to avoid approximation issues when doing the
# intersection below (this is to make sure we overlap with supporting
# surfaces, otherwise a little gap will result from intersection)
# ignore holes in bridges
my $contour = $surface->expolygon->contour->safety_offset;
my $description = $surface->surface_type eq 'bottom' ? 'bridge/overhang' : 'reverse bridge';
# offset the contour and intersect it with the internal surfaces to discover
# which of them has contact with our bridge
my @supporting_surfaces = ();
my ($contour_offset) = $contour->offset($Slic3r::flow_width / $Slic3r::resolution);
foreach my $internal_surface (@internal_surfaces) {
my $intersection = intersection_ex([$contour_offset], [$internal_surface->contour->p]);
if (@$intersection) {
push @supporting_surfaces, $internal_surface;
}
}
#use Slic3r::SVG;
#Slic3r::SVG::output(undef, "bridge.svg",
# green_polygons => [ map $_->p, @supporting_surfaces ],
# red_polygons => [ $contour ],
#);
# find all supported edges (as polylines, thus keeping notion of
# consecutive supported edges)
my @supported_polylines = ();
{
my @current_polyline = ();
EDGE: foreach my $edge ($contour->lines) {
for my $supporting_surface (@supporting_surfaces) {
local $Slic3r::Geometry::epsilon = 1E+7;
if (Slic3r::Geometry::polygon_has_subsegment($supporting_surface->contour->p, $edge)) {
push @current_polyline, $edge;
next EDGE;
next SURFACE unless @supporting_surfaces;
Slic3r::debugf " Found $description on layer %d with %d support(s)\n",
$self->id, scalar(@supporting_surfaces);
my $bridge_angle = undef;
if ($surface->surface_type eq 'bottom') {
# detect optimal bridge angle
my $bridge_over_hole = 0;
my @edges = (); # edges are POLYLINES
foreach my $supporting_surface (@supporting_surfaces) {
my @surface_edges = $supporting_surface->contour->clip_with_polygon($contour_offset);
if (@surface_edges == 1 && @{$supporting_surface->contour->p} == @{$surface_edges[0]->p}) {
$bridge_over_hole = 1;
} else {
foreach my $edge (@surface_edges) {
shift @{$edge->points};
pop @{$edge->points};
}
}
if (@current_polyline) {
push @supported_polylines, [@current_polyline];
@current_polyline = ();
}
push @edges, @surface_edges;
}
Slic3r::debugf " Bridge is supported on %d edge(s)\n", scalar(@edges);
Slic3r::debugf " and covers a hole\n" if $bridge_over_hole;
if (0) {
require "Slic3r/SVG.pm";
Slic3r::SVG::output(undef, "bridge.svg",
polylines => [ map $_->p, @edges ],
);
}
if (@edges == 2) {
my @chords = map Slic3r::Line->new($_->points->[0], $_->points->[-1]), @edges;
my @midpoints = map $_->midpoint, @chords;
$bridge_angle = -Slic3r::Geometry::rad2deg(Slic3r::Geometry::line_atan(\@midpoints) + PI/2);
Slic3r::debugf "Optimal infill angle of bridge on layer %d is %d degrees\n", $self->id, $bridge_angle;
}
push @supported_polylines, [@current_polyline] if @current_polyline;
}
# defensive programming, this shouldn't happen
if (@supported_polylines == 0) {
Slic3r::debugf "Found $description with no supports on layer %d; ignoring\n", $self->id;
next SURFACE;
}
if (@supported_polylines == 1) {
Slic3r::debugf "Found $description with only one support on layer %d; ignoring\n", $self->id;
next SURFACE;
}
# now connect the first point to the last of each polyline
@supported_polylines = map [ $_->[0]->[0], $_->[-1]->[-1] ], @supported_polylines;
# @supported_polylines becomes actually an array of lines
# if we got more than two supports, get the longest two
if (@supported_polylines > 2) {
my %lengths = map { $_ => Slic3r::Geometry::line_length($_) } @supported_polylines;
@supported_polylines = sort { $lengths{"$a"} <=> $lengths{"$b"} } @supported_polylines;
@supported_polylines = @supported_polylines[-2,-1];
}
# connect the midpoints, that will give the the optimal infill direction
my @midpoints = map Slic3r::Geometry::midpoint($_), @supported_polylines;
my $bridge_angle = -Slic3r::Geometry::rad2deg(Slic3r::Geometry::line_atan(\@midpoints) + PI/2);
Slic3r::debugf "Optimal infill angle of bridge on layer %d is %d degrees\n", $self->id, $bridge_angle;
# detect which neighbor surfaces are now supporting our bridge
my @supporting_neighbor_surfaces = ();
foreach my $supporting_surface (@supporting_surfaces) {
local $Slic3r::Geometry::epsilon = 1E+7;
push @supporting_neighbor_surfaces, $supporting_surface
if grep Slic3r::Geometry::polygon_has_vertex($supporting_surface->contour->p, $_),
map $_->[0], @supported_polylines;
}
# defensive programming, this shouldn't happen
if (@supporting_neighbor_surfaces == 0) {
Slic3r::debugf "Couldn't find supporting surfaces on layer %d; ignoring\n", $self->id;
next SURFACE;
}
# now, extend our bridge by taking a portion of supporting surfaces
@ -443,7 +428,7 @@ sub process_bridges {
# calculate the new bridge
my $intersection = intersection_ex(
[ $contour, map $_->p, @supporting_neighbor_surfaces ],
[ $contour, map $_->p, @supporting_surfaces ],
[ $bridge_offset ],
);
push @{$self->bridges}, map Slic3r::Surface::Bridge->cast_from_expolygon($_,