Implement nearest point index and split at index to avoid search for point.

lib/Slic3r/ExtrusionLoop.pm

@@ -5,7 +5,7 @@ use Moo;
 has 'polygon' => (
     is          => 'rw',
     required    => 1,
-    handles     => [qw(is_printable nearest_point_to reverse)],
+    handles     => [qw(is_printable nearest_point_index_to reverse)],
 );
 
 has 'flow_spacing' => (is => 'rw');
@@ -29,6 +29,23 @@ sub shortest_path {
     return $self;
 }
 
+sub split_at_index {
+    my $self = shift;
+    my ($index) = @_;
+
+    $self->deserialize;
+
+    my @new_points = ();
+    push @new_points, @{$self->polygon}[$index .. $#{$self->polygon}];
+    push @new_points, @{$self->polygon}[0 .. $index];
+    
+    return Slic3r::ExtrusionPath->new(
+        polyline    => Slic3r::Polyline->new(\@new_points),
+        role        => $self->role,
+        flow_spacing => $self->flow_spacing,
+    );
+}
+
 sub split_at {
     my $self = shift;
     my ($point) = @_;
@@ -47,21 +64,12 @@ sub split_at {
     }
     die "Point not found" if $i == -1;
     
-    my @new_points = ();
+    return $self->split_at_index($i);
-    push @new_points, @{$self->polygon}[$i .. $#{$self->polygon}];
-    push @new_points, @{$self->polygon}[0 .. $i];
-    
-    return Slic3r::ExtrusionPath->new(
-        polyline    => Slic3r::Polyline->new(\@new_points),
-        role        => $self->role,
-        flow_spacing => $self->flow_spacing,
-    );
 }
 
 sub split_at_first_point {
     my $self = shift;
-    $self->deserialize;
+    return $self->split_at_index(0);
-    return $self->split_at($self->polygon->[0]);
 }
 
 # although a loop doesn't have endpoints, this method is provided to allow

lib/Slic3r/Fill/Concentric.pm

@@ -57,10 +57,11 @@ sub fill_surface {
         $loop->polygon->make_counter_clockwise;
         
         # find the point of the loop that is closest to the current extruder position
-        $cur_pos = $loop->nearest_point_to($cur_pos);
+        my $index = $loop->nearest_point_index_to($cur_pos);
+        $cur_pos = $loop->polygon->[0];
         
         # split the loop at the starting point and make a path
-        my $path = $loop->split_at($cur_pos);
+        my $path = $loop->split_at_index($index);
         $path->deserialize;
         
         # clip the path to avoid the extruder to get exactly on the first point of the loop

lib/Slic3r/GCode.pm

@@ -103,10 +103,10 @@ sub extrude_loop {
         $last_pos = Slic3r::Point->new(scale $Slic3r::print_center->[X], scale $Slic3r::bed_size->[Y]);
         $last_pos->rotate(rand(2*PI), $Slic3r::print_center);
     }
-    my $start_at = $loop->nearest_point_to($last_pos);
+    my $start_index = $loop->nearest_point_index_to($last_pos);
     
     # split the loop at the starting point and make a path
-    my $extrusion_path = $loop->split_at($start_at);
+    my $extrusion_path = $loop->split_at_index($start_index);
     $extrusion_path->deserialize;
     
     # clip the path to avoid the extruder to get exactly on the first point of the loop;

lib/Slic3r/Polyline.pm

@@ -97,6 +97,12 @@ sub nearest_point_to {
     return Slic3r::Point->new($point);
 }
 
+sub nearest_point_index_to {
+    my $self = shift;
+    my ($point) = @_;
+    return Slic3r::Geometry::nearest_point_index($point, $self);
+}
+
 sub has_segment {
     my $self = shift;
     my ($line) = @_;