New configuration for support material interface extrusion width (#4086)

* different configuration for support material interface extrusion width

* add test for support material interface extrusion width

lib/Slic3r/GUI/PresetEditor.pm

@@ -472,7 +472,7 @@ sub options {
         extrusion_width first_layer_extrusion_width perimeter_extrusion_width 
         external_perimeter_extrusion_width infill_extrusion_width solid_infill_extrusion_width 
         top_infill_extrusion_width support_material_extrusion_width
-        infill_overlap bridge_flow_ratio
+        support_material_interface_extrusion_width infill_overlap bridge_flow_ratio
         xy_size_compensation resolution shortcuts compatible_printers
         print_settings_id
     )
@@ -685,7 +685,8 @@ sub build {
                 for qw(extrusion_width first_layer_extrusion_width
                     perimeter_extrusion_width external_perimeter_extrusion_width
                     infill_extrusion_width solid_infill_extrusion_width
-                    top_infill_extrusion_width support_material_extrusion_width);
+                    top_infill_extrusion_width support_material_interface_extrusion_width 
+                    support_material_extrusion_width);
         }
         {
             my $optgroup = $page->new_optgroup('Overlap');
@@ -923,7 +924,8 @@ sub _update {
         for qw(support_material_threshold support_material_pattern 
             support_material_spacing support_material_angle
             support_material_interface_layers dont_support_bridges
-            support_material_extrusion_width support_material_contact_distance);
+            support_material_extrusion_width support_material_interface_extrusion_width
+            support_material_contact_distance);
 
     $self->get_field($_)->toggle($have_support_material && $have_support_interface)
         for qw(support_material_interface_spacing support_material_interface_extruder

lib/Slic3r/Print/Object.pm

@@ -670,11 +670,16 @@ sub support_material_flow {
     my $extruder = ($role == FLOW_ROLE_SUPPORT_MATERIAL)
         ? $self->config->support_material_extruder
         : $self->config->support_material_interface_extruder;
+
+    my $width = $self->config->support_material_extrusion_width || $self->config->extrusion_width;
+    if ($role == FLOW_ROLE_SUPPORT_MATERIAL_INTERFACE) {
+        $width = $self->config->support_material_interface_extrusion_width || $width;
+    }
     
     # we use a bogus layer_height because we use the same flow for all
     # support material layers
     return Slic3r::Flow->new_from_width(
-        width               => $self->config->support_material_extrusion_width || $self->config->extrusion_width,
+        width               => $width,
         role                => $role,
         nozzle_diameter     => $self->print->config->nozzle_diameter->[$extruder-1] // $self->print->config->nozzle_diameter->[0],
         layer_height        => $self->config->layer_height,

t/support.t

@@ -1,4 +1,4 @@
-use Test::More tests => 28;
+use Test::More tests => 29;
 use strict;
 use warnings;
 
@@ -10,7 +10,7 @@ BEGIN {
 
 use List::Util qw(first);
 use Slic3r;
-use Slic3r::Geometry qw(epsilon scale);
+use Slic3r::Geometry qw(epsilon scale PI);
 use Slic3r::Geometry::Clipper qw(diff);
 use Slic3r::Test;
 
@@ -114,7 +114,6 @@ use Slic3r::Test;
     my %first_object_layer_speeds = ();  # F => 1
     Slic3r::GCode::Reader->new->parse(Slic3r::Test::gcode($print), sub {
         my ($self, $cmd, $args, $info) = @_;
-        
         if ($info->{extruding} && $info->{dist_XY} > 0) {
             if ($layer_id <= $config->raft_layers) {
                 # this is a raft layer or the first object layer
@@ -141,6 +140,61 @@ use Slic3r::Test;
         'bridge speed used in first object layer';
 }
 
+{
+    my $config = Slic3r::Config->new_from_defaults;
+    $config->set('layer_height', 0.2);
+    $config->set('skirts', 0);
+    $config->set('raft_layers', 5);
+    $config->set('support_material_pattern', 'rectilinear');
+    $config->set('support_material_extrusion_width', 0.4);
+    $config->set('support_material_interface_extrusion_width', 0.6);
+    $config->set('support_material_interface_layers', 2);
+    $config->set('first_layer_extrusion_width', '100%');
+    $config->set('bridge_speed', 99);
+    $config->set('cooling', 0);                 # prevent speed alteration
+    $config->set('first_layer_speed', '100%');  # prevent speed alteration
+    $config->set('start_gcode', '');            # prevent any unexpected Z move
+    my $print = Slic3r::Test::init_print('20mm_cube', config => $config);
+
+    my $layer_id = -1;
+    my $success = 1;
+    Slic3r::GCode::Reader->new->parse(Slic3r::Test::gcode($print), sub {
+        my ($self, $cmd, $args, $info) = @_;
+        if ($info->{extruding} && $info->{dist_XY} > 0) {
+            # this is a raft layer
+            if (($layer_id < $config->raft_layers) && ($layer_id > 0)) {
+                my $width;
+                my $support_layer_height = $config->nozzle_diameter->[0] * 0.75;
+
+                # support layer
+                if ($config->raft_layers - $config->support_material_interface_layers > $layer_id) {
+                    $width = $config->support_material_extrusion_width;
+                }
+                # interface layer
+                else {
+                    $width = $config->support_material_interface_extrusion_width;
+                }
+                my $expected_E_per_mm3 = 4 / (($config->filament_diameter->[0]**2) * PI);
+                my $expected_mm3_per_mm = $width * $support_layer_height + ($support_layer_height**2) / 4.0 * (PI-4.0);
+                my $expected_e_per_mm = $expected_E_per_mm3 * $expected_mm3_per_mm;
+                
+                my $e_per_mm = ($info->{dist_E} / $info->{dist_XY});;
+                
+                my $diff = abs($e_per_mm - $expected_e_per_mm);
+
+                if ($diff > 0.001) {
+                    $success = 0;
+                }
+            }
+        } elsif ($cmd eq 'G1' && $info->{dist_Z} > 0) {
+            $layer_id++;
+        }
+    });
+
+    ok $success,
+        'support material interface extrusion width is used for interfaces';
+}
+
 {
     my $config = Slic3r::Config->new_from_defaults;
     $config->set('skirts', 0);

xs/src/libslic3r/PrintConfig.cpp

@@ -1430,6 +1430,18 @@ PrintConfigDef::PrintConfigDef()
     def->min = 1;
     def->default_value = new ConfigOptionInt(1);
 
+    def = this->add("support_material_interface_extrusion_width", coFloatOrPercent);
+    def->label = "Support material";
+    def->gui_type = "f_enum_open";
+    def->category = "Extrusion Width";
+    def->tooltip = "Set this to a non-zero value to set a manual extrusion width for support material interface. If expressed as percentage (for example 90%) it will be computed over layer height.";
+    def->sidetext = "mm or %";
+    def->cli = "support-material-interface-extrusion-width=s";
+    def->min = 0;
+    def->enum_values.push_back("0");
+    def->enum_labels.push_back("default");
+    def->default_value = new ConfigOptionFloatOrPercent(0, false);
+
     def = this->add("support_material_interface_layers", coInt);
     def->label = "Interface layers";
     def->category = "Support material";

xs/src/libslic3r/PrintConfig.hpp

@@ -174,6 +174,7 @@ class PrintObjectConfig : public virtual StaticPrintConfig
     ConfigOptionInt                 support_material_extruder;
     ConfigOptionFloatOrPercent      support_material_extrusion_width;
     ConfigOptionInt                 support_material_interface_extruder;
+    ConfigOptionFloatOrPercent      support_material_interface_extrusion_width;
     ConfigOptionInt                 support_material_interface_layers;
     ConfigOptionFloat               support_material_interface_spacing;
     ConfigOptionFloatOrPercent      support_material_interface_speed;
@@ -210,6 +211,7 @@ class PrintObjectConfig : public virtual StaticPrintConfig
         OPT_PTR(support_material_extruder);
         OPT_PTR(support_material_extrusion_width);
         OPT_PTR(support_material_interface_extruder);
+        OPT_PTR(support_material_interface_extrusion_width);
         OPT_PTR(support_material_interface_layers);
         OPT_PTR(support_material_interface_spacing);
         OPT_PTR(support_material_interface_speed);

xs/src/libslic3r/PrintObject.cpp

@@ -244,6 +244,7 @@ PrintObject::invalidate_state_by_config(const PrintConfigBase &config)
             || opt_key == "support_material_extrusion_width"
             || opt_key == "support_material_interface_layers"
             || opt_key == "support_material_interface_extruder"
+            || opt_key == "support_material_interface_extrusion_width"
             || opt_key == "support_material_interface_spacing"
             || opt_key == "support_material_interface_speed"
             || opt_key == "support_material_buildplate_only"