New top-infill-extrusion-width option

README.markdown

@@ -289,6 +289,8 @@ The author of the Silk icon set is Mark James.
                             Set a different extrusion width for perimeters
         --infill-extrusion-width
                             Set a different extrusion width for infill
+        --top-infill-extrusion-width
+                            Set a different extrusion width for top infill
         --support-material-extrusion-width
                             Set a different extrusion width for support material
         --bridge-flow-ratio Multiplier for extrusion when bridging (> 0, default: 1)

lib/Slic3r/Config.pm

@@ -422,6 +422,14 @@ our $Options = {
         type    => 'f',
         default => 0,
     },
+    'top_infill_extrusion_width' => {
+        label   => 'Top infill',
+        tooltip => 'Set this to a non-zero value to set a manual extrusion width for infill for top surfaces. You may want to use thinner extrudates to fill all narrow regions and get a smoother finish. If expressed as percentage (for example 90%) if will be computed over layer height.',
+        sidetext => 'mm or % (leave 0 for default)',
+        cli     => 'top-infill-extrusion-width=s',
+        type    => 'f',
+        default => 0,
+    },
     'support_material_extrusion_width' => {
         label   => 'Support material',
         tooltip => 'Set this to a non-zero value to set a manual extrusion width for support material. If expressed as percentage (for example 90%) if will be computed over layer height.',

lib/Slic3r/Fill.pm

@@ -102,7 +102,9 @@ sub make_fill {
     SURFACE: foreach my $surface (@surfaces) {
         my $filler          = $Slic3r::Config->fill_pattern;
         my $density         = $Slic3r::Config->fill_density;
-        my $flow_spacing    = $layerm->infill_flow->spacing;
+        my $flow_spacing    = ($surface->surface_type == S_TYPE_TOP)
+            ? $layerm->top_infill_flow->spacing
+            : $layerm->infill_flow->spacing;
         my $is_bridge       = $layerm->id > 0 && $surface->is_bridge;
         my $is_solid        = $surface->is_solid;
         

lib/Slic3r/GUI/Tab.pm

@@ -510,7 +510,7 @@ sub build {
         {
             title => 'Extrusion width',
             label_width => 180,
-            options => [qw(extrusion_width first_layer_extrusion_width perimeter_extrusion_width infill_extrusion_width support_material_extrusion_width)],
+            options => [qw(extrusion_width first_layer_extrusion_width perimeter_extrusion_width infill_extrusion_width top_infill_extrusion_width support_material_extrusion_width)],
         },
         {
             title => 'Flow',

lib/Slic3r/Layer/Region.pm

@@ -16,6 +16,7 @@ has 'layer' => (
 has 'region'            => (is => 'ro', required => 1, handles => [qw(extruders)]);
 has 'perimeter_flow'    => (is => 'rw');
 has 'infill_flow'       => (is => 'rw');
+has 'top_infill_flow'   => (is => 'rw');
 has 'infill_area_threshold' => (is => 'lazy');
 has 'overhang_width'    => (is => 'lazy');
 
@@ -62,9 +63,12 @@ sub _update_flows {
             ($self->region->first_layer_flows->{perimeter} || $self->region->flows->{perimeter});
         $self->infill_flow
             ($self->region->first_layer_flows->{infill} || $self->region->flows->{infill});
+        $self->top_infill_flow
+            ($self->region->first_layer_flows->{top_infill} || $self->region->flows->{top_infill});
     } else {
         $self->perimeter_flow($self->region->flows->{perimeter});
         $self->infill_flow($self->region->flows->{infill});
+        $self->top_infill_flow($self->region->flows->{top_infill});
     }
 }
 

lib/Slic3r/Print.pm

@@ -200,10 +200,11 @@ sub init_extruders {
         my $region = $self->regions->[$region_id];
         
         # per-role extruders and flows
-        for (qw(perimeter infill)) {
+        for (qw(perimeter infill top_infill)) {
+            my $extruder_name = $_ eq 'top_infill' ? 'infill' : $_;
             $region->extruders->{$_} = ($self->regions_count > 1)
                 ? $self->extruders->[$extruder_mapping{$region_id}]
-                : $self->extruders->[$self->config->get("${_}_extruder")-1];
+                : $self->extruders->[$self->config->get("${extruder_name}_extruder")-1];
             $region->flows->{$_} = $region->extruders->{$_}->make_flow(
                 width => $self->config->get("${_}_extrusion_width") || $self->config->extrusion_width,
             );

slic3r.pl

@@ -337,6 +337,8 @@ $j
                         Set a different extrusion width for perimeters
     --infill-extrusion-width
                         Set a different extrusion width for infill
+    --top-infill-extrusion-width
+                        Set a different extrusion width for top infill
     --support-material-extrusion-width
                         Set a different extrusion width for support material
     --bridge-flow-ratio Multiplier for extrusion when bridging (> 0, default: $config->{bridge_flow_ratio})