Fixes for bridges

lib/Slic3r/Geometry.pm

@@ -15,6 +15,8 @@ our @EXPORT_OK = qw(
     sum_vectors multiply_vector subtract_vectors dot perp polygon_points_visibility
     line_intersection bounding_box bounding_box_intersect 
     clip_segment_complex_polygon longest_segment angle3points
+    polyline_remove_parallel_continuous_edges polyline_remove_acute_vertices
+    polygon_remove_acute_vertices polygon_remove_parallel_continuous_edges
 );
 
 use Slic3r::Geometry::DouglasPeucker qw(Douglas_Peucker);
@@ -575,4 +577,39 @@ sub angle3points {
     return $angle <= 0 ? $angle + 2*PI() : $angle;
 }
 
+sub polyline_remove_parallel_continuous_edges {
+    my ($points, $isPolygon) = @_;
+    
+    for (my $i = $isPolygon ? 0 : 2; $i <= $#$points; $i++) {
+        if (Slic3r::Geometry::lines_parallel([$points->[$i-2], $points->[$i-1]], [$points->[$i-1], $points->[$i]])) {
+            # we can remove $points->[$i-1]
+            splice @$points, $i-1, 1;
+            $i--;
+        }
+    }
+}
+
+sub polygon_remove_parallel_continuous_edges {
+    my ($points) = @_;
+    return polyline_remove_parallel_continuous_edges($points, 1);
+}
+
+sub polyline_remove_acute_vertices {
+    my ($points, $isPolygon) = @_;
+    
+    for (my $i = $isPolygon ? -1 : 1; $i < $#$points; $i++) {
+        my $angle = angle3points($points->[$i], $points->[$i-1], $points->[$i+1]);
+        if ($angle < 0.01 || $angle >= 2*PI - 0.01) {
+            # we can remove $points->[$i]
+            splice @$points, $i, 1;
+            $i--;
+        }
+    }
+}
+
+sub polygon_remove_acute_vertices {
+    my ($points) = @_;
+    return polyline_remove_acute_vertices($points, 1);
+}
+
 1;

lib/Slic3r/Layer.pm

@@ -157,8 +157,21 @@ sub make_surfaces {
         my %seen_points = map { $get_point_id->($points[$_]) => $_ } 0..1;
         
         CYCLE: while (1) {
-            my $next_lines = $pointmap{ $get_point_id->($points[-1]) }
-                or die sprintf "No lines start at point %d,%d. This shouldn't happen", @{$points[-1]};
+            my $next_lines = $pointmap{ $get_point_id->($points[-1]) };
+            
+            # shouldn't we find the point, let's try with a slower algorithm
+            # as approximation may make the coordinates differ
+            if (!$next_lines) {
+                local $Slic3r::Geometry::epsilon = 1;
+                for (keys %pointmap) {
+                    $next_lines = $pointmap{$_} if points_coincide($points[-1], [ split /,/, $_ ]);
+                    last if $next_lines;
+                }
+            }
+            
+            $next_lines
+                or die sprintf "No lines start at point %s. This shouldn't happen", 
+                    $get_point_id->($points[-1]);
             last CYCLE if !@$next_lines;
             
             my @ordered_next_lines = sort 
@@ -256,6 +269,12 @@ sub process_bridges {
         # in a convex polygon; this will print thin membranes eventually
         my $surface_p = convex_hull($surface->contour->p);
         
+            #use Slic3r::SVG;
+            #Slic3r::SVG::output(undef, "bridge.svg",
+            #    green_polygons  => [ map $_->p, @supporting_surfaces ],
+            #    red_polygons    => [ $surface_p ],
+            #);
+        
         # find all supported edges (as polylines, thus keeping notion of 
         # consecutive supported edges)
         my @supported_polylines = ();

lib/Slic3r/Polyline.pm

@@ -2,6 +2,8 @@ package Slic3r::Polyline;
 use Moo;
 
 use Math::Clipper qw();
+use Slic3r::Geometry qw(polyline_remove_parallel_continuous_edges polyline_remove_acute_vertices
+    polygon_remove_acute_vertices polygon_remove_parallel_continuous_edges);
 use Sub::Quote;
 use XXX;
 
@@ -46,18 +48,24 @@ sub p {
 
 sub merge_continuous_lines {
     my $self = shift;
-    
-    my @points = map $_->p, @{$self->points};
-    for (my $i = 2; $i <= $#points; $i++) {
-        if (Slic3r::Geometry::lines_parallel([$points[$i-2], $points[$i-1]], [$points[$i-1], $points[$i]])) {
-            # we can remove $points[$i-1]
-            splice @points, $i-1, 1;
-            
-            $i--;
-        }
+    my $points = $self->p;
+    if ($self->isa('Slic3r::Polyline::Closed')) {
+        polygon_remove_parallel_continuous_edges($points);
+    } else {
+        polyline_remove_parallel_continuous_edges($points);
     }
-    
-    @{$self->points} = map Slic3r::Point->cast($_), @points;
+    @{$self->points} = map Slic3r::Point->cast($_), @$points;
+}
+
+sub remove_acute_vertices {
+    my $self = shift;
+    my $points = $self->p;
+    if ($self->isa('Slic3r::Polyline::Closed')) {
+        polygon_remove_acute_vertices($points);
+    } else {
+        polyline_remove_acute_vertices($points);
+    }
+    @{$self->points} = map Slic3r::Point->cast($_), @$points;
 }
 
 sub cleanup {

lib/Slic3r/Polyline/Closed.pm

@@ -15,18 +15,6 @@ sub lines {
     return @lines;
 }
 
-# superclass doesn't check whether last line of our closed polyline
-# is parallel to first one, so let's do it here
-sub merge_continuous_lines {
-    my $self = shift;
-    $self->SUPER::merge_continuous_lines(@_);
-    
-    my @lines = $self->lines;
-    if ($lines[-1]->parallel_to($lines[0])) {
-        shift @{$self->points};
-    }
-}
-
 sub encloses_point {
     my $self = shift;
     my ($point) = @_;

lib/Slic3r/Print.pm

@@ -120,6 +120,15 @@ sub detect_surfaces_type {
         # of current layer and lower one)
         if ($lower_layer) {
             @bottom = $surface_difference->($layer->surfaces, $lower_layer->surfaces, 'bottom');
+            for (@bottom) {
+                $_->contour->merge_continuous_lines;
+                $_->contour->remove_acute_vertices;
+        
+                # okay, this is an Ugly Hack(tm) to avoid floating point math problems
+                # with diagonal bridges. will find a nicer solution, promised.
+                my $offset = offset([$_->contour->p], 100, 100, JT_MITER, 2);
+                @{$_->contour->points} = map Slic3r::Point->cast($_), @{ $offset->[0] };
+            }
             
             #Slic3r::SVG::output(undef, "layer_" . $layer->id . "_diff.svg",
             #    green_polygons  => [ map $_->p, @{$layer->surfaces} ],

lib/Slic3r/SVG.pm

@@ -65,7 +65,7 @@ sub output {
     
     foreach my $type (qw(points red_points)) {
         if ($things{$type}) {
-            my ($colour, $r) = $type eq 'points' ? ('black', 2) : ('red', 3);
+            my ($colour, $r) = $type eq 'points' ? ('black', 5) : ('red', 3);
             my $g = $svg->group(
                 style => {
                     'stroke-width' => 2,