From 56691c1dea6a140e1c816b855e5f26fcf5d00a86 Mon Sep 17 00:00:00 2001
From: Alessandro Ranellucci <aar@cpan.org>
Date: Tue, 13 Dec 2011 17:34:31 +0100
Subject: [PATCH 1/4] Model extrusion threads as rectangles with semicircles at
 the end. Remove overlap_ratio setting. #109 #112

---
 README.markdown                 |  2 --
 lib/Slic3r.pm                   |  4 +---
 lib/Slic3r/Config.pm            | 27 ++++++++++-----------------
 lib/Slic3r/Extruder.pm          | 14 +++++++-------
 lib/Slic3r/ExtrusionPath.pm     |  3 +--
 lib/Slic3r/Fill.pm              | 11 ++++-------
 lib/Slic3r/Fill/Concentric.pm   |  6 +++---
 lib/Slic3r/Fill/PlanePath.pm    |  2 +-
 lib/Slic3r/Fill/Rectilinear.pm  | 15 +++++++++------
 lib/Slic3r/Fill/Rectilinear2.pm |  2 +-
 lib/Slic3r/GUI/SkeinPanel.pm    |  2 +-
 lib/Slic3r/Layer.pm             |  2 +-
 lib/Slic3r/Perimeter.pm         |  4 ++--
 lib/Slic3r/Polyline/Closed.pm   |  2 +-
 lib/Slic3r/Print.pm             |  2 +-
 slic3r.pl                       |  2 --
 16 files changed, 43 insertions(+), 57 deletions(-)

diff --git a/README.markdown b/README.markdown
index da49afc2a..77e9371f6 100644
--- a/README.markdown
+++ b/README.markdown
@@ -170,8 +170,6 @@ The author is Alessandro Ranellucci (me).
                             Calculate the extrusion width as the layer height multiplied by
                             this value (> 0, default: calculated automatically)
         --bridge-flow-ratio Multiplier for extrusion when bridging (> 0, default: 1)
-        --overlap-ratio     Overlap between extrusion threads expressed as a ratio over extrusion 
-                            width (> 0, default: 0.15)
 
 If you want to change a preset file, just do
 
diff --git a/lib/Slic3r.pm b/lib/Slic3r.pm
index 84e36dafb..d165b85fe 100644
--- a/lib/Slic3r.pm
+++ b/lib/Slic3r.pm
@@ -66,10 +66,8 @@ our $infill_every_layers    = 1;
 # flow options
 our $extrusion_width_ratio  = 0;
 our $bridge_flow_ratio      = 1;
-our $flow_speed_ratio       = 1;
+our $overlap_factor         = 0.15;
 our $flow_width;
-our $overlap_ratio          = 0.15;
-our $flow_spacing;
 
 # print options
 our $perimeters         = 3;
diff --git a/lib/Slic3r/Config.pm b/lib/Slic3r/Config.pm
index 1a391219d..ee12502f5 100644
--- a/lib/Slic3r/Config.pm
+++ b/lib/Slic3r/Config.pm
@@ -137,11 +137,6 @@ our $Options = {
         cli     => 'bridge-flow-ratio=f',
         type    => 'f',
     },
-    'overlap_ratio' => {
-        label   => 'Extrusion overlap (ratio  over extrusion width)',  # the double space here prevents a bug in WxWidgets (Mac)
-        cli     => 'overlap-ratio=f',
-        type    => 'f',
-    },
     
     # print options
     'perimeters' => {
@@ -367,23 +362,21 @@ sub validate {
         if $Slic3r::layer_height > $Slic3r::nozzle_diameter;
     die "First layer height can't be greater than --nozzle-diameter\n"
         if ($Slic3r::layer_height * $Slic3r::first_layer_height_ratio) > $Slic3r::nozzle_diameter;
-    $Slic3r::flow_width = ($Slic3r::nozzle_diameter**2) 
-        * $Slic3r::flow_speed_ratio * PI / (4 * $Slic3r::layer_height);
     
-    my $max_flow_width = $Slic3r::layer_height + $Slic3r::nozzle_diameter;
     if ($Slic3r::extrusion_width_ratio) {
-        my $flow_width = $Slic3r::layer_height * $Slic3r::extrusion_width_ratio;
-        $Slic3r::flow_speed_ratio = $flow_width / $Slic3r::flow_width;
-        $Slic3r::flow_width = $flow_width;
-    } elsif ($Slic3r::flow_width > $max_flow_width) {
-        $Slic3r::flow_speed_ratio = $max_flow_width / $Slic3r::flow_width;
-        $Slic3r::flow_width = $max_flow_width;
+        $Slic3r::flow_width = $Slic3r::layer_height * $Slic3r::extrusion_width_ratio;
+    } else {
+        # here we calculate a sane default by matching the flow speed (at the nozzle)
+        # and the feed rate
+        $Slic3r::flow_width = (($Slic3r::nozzle_diameter**2) * PI + ($Slic3r::layer_height**2) * (4 - PI)) / (4 * $Slic3r::layer_height);
+        
+        my $max_flow_width = $Slic3r::layer_height + $Slic3r::nozzle_diameter;
+        $Slic3r::flow_width = $max_flow_width if $Slic3r::flow_width > $max_flow_width;
+        $Slic3r::flow_width = $Slic3r::nozzle_diameter * 1.05
+            if $Slic3r::flow_width < $Slic3r::nozzle_diameter;
     }
-    $Slic3r::flow_spacing = $Slic3r::flow_width * (1-$Slic3r::overlap_ratio);
     
     Slic3r::debugf "Flow width = $Slic3r::flow_width\n";
-    Slic3r::debugf "Flow speed ratio = $Slic3r::flow_speed_ratio\n";
-    Slic3r::debugf "Flow spacing = $Slic3r::flow_spacing\n";
     
     # --perimeters
     die "Invalid value for --perimeters\n"
diff --git a/lib/Slic3r/Extruder.pm b/lib/Slic3r/Extruder.pm
index 9822e1204..51deaf192 100644
--- a/lib/Slic3r/Extruder.pm
+++ b/lib/Slic3r/Extruder.pm
@@ -7,7 +7,6 @@ has 'layer'              => (is => 'rw');
 has 'shift_x'            => (is => 'ro', default => sub {0} );
 has 'shift_y'            => (is => 'ro', default => sub {0} );
 has 'z'                  => (is => 'rw', default => sub {0} );
-has 'flow_ratio'         => (is => 'rw', default => sub {1});
 has 'print_feed_rate'    => (is => 'rw');
 
 has 'extrusion_distance' => (is => 'rw', default => sub {0} );
@@ -77,7 +76,7 @@ sub extrude_loop {
     my $extrusion_path = $loop->split_at($start_at);
     
     # clip the path to avoid the extruder to get exactly on the first point of the loop
-    $extrusion_path->clip_end(scale $Slic3r::flow_spacing);
+    $extrusion_path->clip_end(scale $Slic3r::flow_width);
     
     # extrude along the path
     return $self->extrude($extrusion_path, $description);
@@ -119,13 +118,14 @@ sub extrude {
     $gcode .= $self->unretract if $self->retracted;
     
     # calculate extrusion length per distance unit
+    my $w = $path->flow_width || $Slic3r::flow_width;
+    my $h = $path->depth_layers * $Slic3r::layer_height;
+    $h = $w if $path->role eq 'bridge';
+    
     my $e = $Slic3r::resolution
-        * (($Slic3r::nozzle_diameter**2) / ($Slic3r::filament_diameter ** 2))
-        * $Slic3r::flow_speed_ratio 
-        * $self->flow_ratio
-        * ($path->flow_ratio || 1)
+        * ($w * $h + ($Slic3r::layer_height**2) / 4 * (PI - 4) + $Slic3r::overlap_factor * (($Slic3r::layer_height**2) - ($Slic3r::layer_height**2) / 4 * PI))
         * $Slic3r::extrusion_multiplier
-        * $path->depth_layers;
+        * (4 / (($Slic3r::filament_diameter ** 2) * PI));
     
     # extrude arc or line
     $self->print_feed_rate(
diff --git a/lib/Slic3r/ExtrusionPath.pm b/lib/Slic3r/ExtrusionPath.pm
index 17e627659..fb61761bb 100644
--- a/lib/Slic3r/ExtrusionPath.pm
+++ b/lib/Slic3r/ExtrusionPath.pm
@@ -7,8 +7,7 @@ extends 'Slic3r::Polyline';
 # expressed in layers
 has 'depth_layers' => (is => 'ro', default => sub {1});
 
-# multiplier for the flow rate
-has 'flow_ratio' => (is => 'rw');
+has 'flow_width' => (is => 'rw');
 
 # perimeter/fill/solid-fill/bridge/skirt
 has 'role'         => (is => 'rw', required => 1);
diff --git a/lib/Slic3r/Fill.pm b/lib/Slic3r/Fill.pm
index 545582a7c..aaddb1b8e 100644
--- a/lib/Slic3r/Fill.pm
+++ b/lib/Slic3r/Fill.pm
@@ -87,8 +87,7 @@ sub make_fill {
     SURFACE: foreach my $surface (@surfaces) {
         my $filler          = $Slic3r::fill_pattern;
         my $density         = $Slic3r::fill_density;
-        my $flow_spacing    = $Slic3r::flow_spacing;
-        my $flow_ratio      = 1;
+        my $flow_width      = $Slic3r::flow_width;
         my $is_bridge       = $layer->id > 0 && $surface->surface_type eq 'bottom';
         my $is_solid        = $surface->surface_type =~ /^(top|bottom)$/;
         
@@ -98,9 +97,7 @@ sub make_fill {
             $filler = $Slic3r::solid_fill_pattern;
             if ($is_bridge) {
                 $filler = 'rectilinear';
-                $flow_spacing = sqrt($Slic3r::bridge_flow_ratio * ($Slic3r::nozzle_diameter**2)) 
-                    * (1-$Slic3r::overlap_ratio);
-                $flow_ratio = $Slic3r::bridge_flow_ratio;
+                $flow_width = sqrt($Slic3r::bridge_flow_ratio * ($Slic3r::nozzle_diameter**2));
             }
         } else {
             next SURFACE unless $density > 0;
@@ -109,7 +106,7 @@ sub make_fill {
         my @paths = $self->fillers->{$filler}->fill_surface(
             $surface,
             density         => $density,
-            flow_spacing    => $flow_spacing,
+            flow_width      => $flow_width,
         );
         my $params = shift @paths;
         
@@ -120,7 +117,7 @@ sub make_fill {
                     [ @$_ ],
                     role => ($is_bridge ? 'bridge' : $is_solid ? 'solid-fill' : 'fill'),
                     depth_layers => $surface->depth_layers,
-                    flow_ratio   => $flow_ratio * ($params->{flow_ratio} || 1),
+                    flow_width   => $flow_width,
                 ), @paths,
             ],
         ) if @paths;
diff --git a/lib/Slic3r/Fill/Concentric.pm b/lib/Slic3r/Fill/Concentric.pm
index 7d1ecd1bd..c2d3142bb 100644
--- a/lib/Slic3r/Fill/Concentric.pm
+++ b/lib/Slic3r/Fill/Concentric.pm
@@ -12,8 +12,8 @@ sub fill_surface {
     
     # no rotation is supported for this infill pattern
     
-    my $scaled_flow_spacing = scale $params{flow_spacing};
-    my $distance = $scaled_flow_spacing / $params{density};
+    my $scaled_flow_width = scale $params{flow_width};
+    my $distance = $scaled_flow_width / $params{density};
     
     my @contour_loops = ();
     my @hole_loops = ();
@@ -44,7 +44,7 @@ sub fill_surface {
         my $path = $loop->split_at($cur_pos);
         
         # clip the path to avoid the extruder to get exactly on the first point of the loop
-        $path->clip_end(scale $Slic3r::flow_spacing);
+        $path->clip_end(scale $Slic3r::flow_width);
         
         push @paths, $path->p;
     }
diff --git a/lib/Slic3r/Fill/PlanePath.pm b/lib/Slic3r/Fill/PlanePath.pm
index caf92c948..13bdcdce9 100644
--- a/lib/Slic3r/Fill/PlanePath.pm
+++ b/lib/Slic3r/Fill/PlanePath.pm
@@ -27,7 +27,7 @@ sub fill_surface {
     my $rotate_vector = $self->infill_direction($surface);
     $self->rotate_points($expolygon, $rotate_vector);
     
-    my $distance_between_lines = scale $params{flow_spacing} / $params{density} * $self->multiplier;
+    my $distance_between_lines = scale $params{flow_width} / $params{density} * $self->multiplier;
     my $bounding_box = [ bounding_box(map @$_, $expolygon) ];
     my $bounding_box_polygon = Slic3r::Polygon->new([
         [ $bounding_box->[X1], $bounding_box->[Y1] ],
diff --git a/lib/Slic3r/Fill/Rectilinear.pm b/lib/Slic3r/Fill/Rectilinear.pm
index 313b73c78..5607f09d0 100644
--- a/lib/Slic3r/Fill/Rectilinear.pm
+++ b/lib/Slic3r/Fill/Rectilinear.pm
@@ -3,7 +3,7 @@ use Moo;
 
 extends 'Slic3r::Fill::Base';
 
-use Slic3r::Geometry qw(X1 Y1 X2 Y2 A B X Y scale epsilon);
+use Slic3r::Geometry qw(X1 Y1 X2 Y2 A B X Y scale unscale epsilon);
 use XXX;
 
 sub fill_surface {
@@ -19,14 +19,17 @@ sub fill_surface {
     $bounding_box->[X1] += scale 0.1;
     $bounding_box->[X2] -= scale 0.1;
     
-    my $min_spacing = scale $params{flow_spacing};
+    my $min_spacing = scale $params{flow_width};
     my $distance_between_lines = $min_spacing / $params{density};
     my $line_oscillation = $distance_between_lines - $min_spacing;
     
     my $number_of_lines = int(($bounding_box->[X2] - $bounding_box->[X1]) / $distance_between_lines) + 1;
-    my $extra_space = ($bounding_box->[X2] - $bounding_box->[X1]) % $distance_between_lines;
-    $distance_between_lines += $extra_space / ($number_of_lines - 1) if $number_of_lines > 1;
-    my $flow_ratio = $distance_between_lines / ($min_spacing / $params{density});
+    my $flow_width = undef;
+    if ($params{density} == 1) {
+        my $extra_space = ($bounding_box->[X2] - $bounding_box->[X1]) % $distance_between_lines;
+        $distance_between_lines += $extra_space / ($number_of_lines - 1) if $number_of_lines > 1;
+        $flow_width = unscale $distance_between_lines;
+    }
     
     my @paths = ();
     my $x = $bounding_box->[X1];
@@ -70,7 +73,7 @@ sub fill_surface {
     # paths must be rotated back
     $self->rotate_points_back(\@paths, $rotate_vector);
     
-    return { flow_ratio => $flow_ratio }, @paths;
+    return { flow_width => $flow_width }, @paths;
 }
 
 1;
diff --git a/lib/Slic3r/Fill/Rectilinear2.pm b/lib/Slic3r/Fill/Rectilinear2.pm
index d8b8f0bb0..9ece7ee26 100644
--- a/lib/Slic3r/Fill/Rectilinear2.pm
+++ b/lib/Slic3r/Fill/Rectilinear2.pm
@@ -16,7 +16,7 @@ sub fill_surface {
     my $rotate_vector = $self->infill_direction($surface);
     $self->rotate_points($polygons, $rotate_vector);
     
-    my $distance_between_lines = scale $params{flow_spacing} / $params{density};
+    my $distance_between_lines = scale $params{flow_width} / $params{density};
     my $number_of_lines = int(0.99999999 + $self->max_print_dimension / $distance_between_lines); # ceil
 
     #printf "distance = %f\n", $distance_between_lines;
diff --git a/lib/Slic3r/GUI/SkeinPanel.pm b/lib/Slic3r/GUI/SkeinPanel.pm
index bc8f27192..19209aef5 100644
--- a/lib/Slic3r/GUI/SkeinPanel.pm
+++ b/lib/Slic3r/GUI/SkeinPanel.pm
@@ -59,7 +59,7 @@ sub new {
         },
         extrusion => {
             title => 'Extrusion',
-            options => [qw(extrusion_width_ratio bridge_flow_ratio overlap_ratio)],
+            options => [qw(extrusion_width_ratio bridge_flow_ratio)],
         },
     );
     $self->{panels} = \%panels;
diff --git a/lib/Slic3r/Layer.pm b/lib/Slic3r/Layer.pm
index 47a5c8fce..322f1025c 100644
--- a/lib/Slic3r/Layer.pm
+++ b/lib/Slic3r/Layer.pm
@@ -182,7 +182,7 @@ sub prepare_fill_surfaces {
 sub remove_small_surfaces {
     my $self = shift;
     
-    my $distance = scale $Slic3r::flow_spacing / 2;
+    my $distance = scale $Slic3r::flow_width / 2;
     
     my @surfaces = @{$self->fill_surfaces};
     @{$self->fill_surfaces} = ();
diff --git a/lib/Slic3r/Perimeter.pm b/lib/Slic3r/Perimeter.pm
index 413f205a7..1532dc9d7 100644
--- a/lib/Slic3r/Perimeter.pm
+++ b/lib/Slic3r/Perimeter.pm
@@ -45,12 +45,12 @@ sub make_perimeter {
             push @{ $perimeters[-1] }, [@last_offsets];
             
             # offset distance for inner loops
-            $distance = scale $Slic3r::flow_spacing;
+            $distance = scale $Slic3r::flow_width;
         }
         
         # create one more offset to be used as boundary for fill
         {
-            $distance -= scale $Slic3r::flow_spacing;
+            $distance -= scale $Slic3r::flow_width;
             my @fill_boundaries = map Slic3r::Surface->cast_from_expolygon
                 ($_, surface_type => $surface->surface_type),
                 map $_->offset_ex(-$distance), @last_offsets;
diff --git a/lib/Slic3r/Polyline/Closed.pm b/lib/Slic3r/Polyline/Closed.pm
index 8d9d54c3a..bb321a950 100644
--- a/lib/Slic3r/Polyline/Closed.pm
+++ b/lib/Slic3r/Polyline/Closed.pm
@@ -32,7 +32,7 @@ sub is_printable {
     # if no offset is possible, then polyline is not printable
     my $p = $self->p;
     @$p = reverse @$p if !Math::Clipper::is_counter_clockwise($p);
-    my $offsets = Math::Clipper::offset([$p], -(scale $Slic3r::flow_spacing / 2), $Slic3r::resolution * 100000, JT_MITER, 2);
+    my $offsets = Math::Clipper::offset([$p], -(scale $Slic3r::flow_width / 2), $Slic3r::resolution * 100000, JT_MITER, 2);
     return @$offsets ? 1 : 0;
 }
 
diff --git a/lib/Slic3r/Print.pm b/lib/Slic3r/Print.pm
index 31111e716..552e92002 100644
--- a/lib/Slic3r/Print.pm
+++ b/lib/Slic3r/Print.pm
@@ -335,7 +335,7 @@ sub extrude_skirt {
     # draw outlines from outside to inside
     my @skirts = ();
     for (my $i = $Slic3r::skirts - 1; $i >= 0; $i--) {
-        my $distance = scale ($Slic3r::skirt_distance + ($Slic3r::flow_spacing * $i));
+        my $distance = scale ($Slic3r::skirt_distance + ($Slic3r::flow_width * $i));
         my $outline = offset([$convex_hull], $distance, $Slic3r::resolution * 100, JT_ROUND);
         push @skirts, Slic3r::ExtrusionLoop->cast([ @{$outline->[0]} ], role => 'skirt');
     }
diff --git a/slic3r.pl b/slic3r.pl
index b58dcb18a..d74db5070 100755
--- a/slic3r.pl
+++ b/slic3r.pl
@@ -176,8 +176,6 @@ Usage: slic3r.pl [ OPTIONS ] file.stl
                         Calculate the extrusion width as the layer height multiplied by
                         this value (> 0, default: calculated automatically)
     --bridge-flow-ratio Multiplier for extrusion when bridging (> 0, default: $Slic3r::bridge_flow_ratio)
-    --overlap-ratio     Overlap between extrusion threads expressed as a ratio over extrusion
-                        width (> 0, default: $Slic3r::overlap_ratio)
     
 EOF
     exit ($exit_code || 0);

From 569e737ae1c66015586b7d7bfb6fbd329bac249a Mon Sep 17 00:00:00 2001
From: Alessandro Ranellucci <aar@cpan.org>
Date: Tue, 13 Dec 2011 17:36:03 +0100
Subject: [PATCH 2/4] Only connect infill edges when not doing solid surfaces

---
 lib/Slic3r/Fill/Rectilinear.pm | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/Slic3r/Fill/Rectilinear.pm b/lib/Slic3r/Fill/Rectilinear.pm
index 5607f09d0..b15524454 100644
--- a/lib/Slic3r/Fill/Rectilinear.pm
+++ b/lib/Slic3r/Fill/Rectilinear.pm
@@ -45,7 +45,7 @@ sub fill_surface {
     }
     
     # connect lines
-    {
+    if ($params{density} < 1) {
         my $collection = Slic3r::ExtrusionPath::Collection->new(
             paths => [ map Slic3r::ExtrusionPath->cast([ @$_ ], role => 'bogus'), @paths ],
         );

From 4bee1a12b8fc06d6fe8c07c547258ffbc2b0d4fe Mon Sep 17 00:00:00 2001
From: Alessandro Ranellucci <aar@cpan.org>
Date: Wed, 14 Dec 2011 11:21:43 +0100
Subject: [PATCH 3/4] Take overlap into account for external dimensions

---
 lib/Slic3r/Layer.pm | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/lib/Slic3r/Layer.pm b/lib/Slic3r/Layer.pm
index 322f1025c..85725eee2 100644
--- a/lib/Slic3r/Layer.pm
+++ b/lib/Slic3r/Layer.pm
@@ -124,7 +124,14 @@ sub make_surfaces {
     
     # the contours must be offsetted by half extrusion width inwards
     {
-        my $distance = scale $Slic3r::flow_width / 2;
+        my $distance = $Slic3r::flow_width / 2;
+        if ($Slic3r::overlap_factor) {
+            # our overlap is done by increasing the flow; however external perimeters will grow 
+            # outwards, so we offset by the correct amount
+            $distance = ($Slic3r::flow_width + $Slic3r::overlap_factor * $Slic3r::layer_height * (1 - PI/4)) / 2;
+        }
+        $distance = scale $distance;
+        
         my @surfaces = @{$self->slices};
         @{$self->slices} = ();
         foreach my $surface (@surfaces) {

From 048f7ca46843082cbe057cdfea1afe7841c8917d Mon Sep 17 00:00:00 2001
From: Alessandro Ranellucci <aar@cpan.org>
Date: Wed, 14 Dec 2011 11:35:19 +0100
Subject: [PATCH 4/4] Adjusted flow width for solid infills was ignored

---
 lib/Slic3r/Fill.pm | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/Slic3r/Fill.pm b/lib/Slic3r/Fill.pm
index aaddb1b8e..14fa7deff 100644
--- a/lib/Slic3r/Fill.pm
+++ b/lib/Slic3r/Fill.pm
@@ -117,7 +117,7 @@ sub make_fill {
                     [ @$_ ],
                     role => ($is_bridge ? 'bridge' : $is_solid ? 'solid-fill' : 'fill'),
                     depth_layers => $surface->depth_layers,
-                    flow_width   => $flow_width,
+                    flow_width   => $params->{flow_width},
                 ), @paths,
             ],
         ) if @paths;