Bugfix: incorrect number of raft layers was generated when too few were requested. #1678

lib/Slic3r/Print/Object.pm

@@ -26,17 +26,30 @@ sub BUILD {
  	
     # make layers taking custom heights into account
     my $print_z = my $slice_z = my $height = my $id = 0;
+    my $first_object_layer_height = -1;
     
     # add raft layers
     if ($self->config->raft_layers > 0) {
+        $id += $self->config->raft_layers;
+        
+        # raise first object layer Z by the thickness of the raft itself
+        # plus the extra distance required by the support material logic
         $print_z += $Slic3r::Config->get_value('first_layer_height');
         $print_z += $Slic3r::Config->layer_height * ($self->config->raft_layers - 1);
-        $id += $self->config->raft_layers;
+        
+        # at this stage we don't know which nozzles are actually used for the first layer
+        # so we compute the average of all of them
+        my $nozzle_diameter = sum(@{$Slic3r::Config->nozzle_diameter})/@{$Slic3r::Config->nozzle_diameter};
+        my $distance = Slic3r::Print::SupportMaterial::contact_distance($nozzle_diameter);
+        
+        # force first layer print_z according to the contact distance
+        # (the loop below will raise print_z by such height)
+        $first_object_layer_height = $distance;
     }
     
     # loop until we have at least one layer and the max slice_z reaches the object height
     my $max_z = unscale $self->size->[Z];
-    while (!@{$self->layers} || ($slice_z - $height) <= $max_z) {
+    while (($slice_z - $height) <= $max_z) {
         # assign the default height to the layer according to the general settings
         $height = ($id == 0)
             ? $Slic3r::Config->get_value('first_layer_height')
@@ -53,6 +66,10 @@ sub BUILD {
             }
         }
         
+        if ($first_object_layer_height != -1 && !@{$self->layers}) {
+            $height = $first_object_layer_height;
+        }
+        
         $print_z += $height;
         $slice_z += $height/2;
         

lib/Slic3r/Print/SupportMaterial.pm

@@ -174,7 +174,7 @@ sub contact_area {
                 @{$layer->regions};
             my $nozzle_diameter = sum(@nozzle_diameters)/@nozzle_diameters;
             
-            my $contact_z = $layer->print_z - $nozzle_diameter * 1.5;
+            my $contact_z = $layer->print_z - contact_distance($nozzle_diameter);
             ###$contact_z = $layer->print_z - $layer->height;
             
             # ignore this contact area if it's too low
@@ -636,4 +636,10 @@ sub overlapping_layers {
     } 0..$#$support_z;
 }
 
+# class method
+sub contact_distance {
+    my ($nozzle_diameter) = @_;
+    return $nozzle_diameter * 1.5;
+}
+
 1;

t/gcode.t

@@ -1,4 +1,4 @@
-use Test::More tests => 7;
+use Test::More tests => 8;
 use strict;
 use warnings;
 

t/support.t

@@ -1,4 +1,4 @@
-use Test::More tests => 14;
+use Test::More tests => 15;
 use strict;
 use warnings;
 
@@ -123,4 +123,31 @@ use Slic3r::Test;
         'first object layer is completely supported by raft';
 }
 
+{
+    my $config = Slic3r::Config->new_from_defaults;
+    $config->set('skirts', 0);
+    $config->set('raft_layers', 2);
+    $config->set('layer_height', 0.35);
+    $config->set('first_layer_height', 0.3);
+    $config->set('nozzle_diameter', [0.5]);
+    $config->set('support_material_extruder', 2);
+    $config->set('support_material_interface_extruder', 2);
+    my $print = Slic3r::Test::init_print('20mm_cube', config => $config);
+    my %raft_z = ();  # z => 1
+    my $tool = undef;
+    Slic3r::GCode::Reader->new->parse(Slic3r::Test::gcode($print), sub {
+        my ($self, $cmd, $args, $info) = @_;
+        
+        if ($cmd =~ /^T(\d+)/) {
+            $tool = $1;
+        } elsif ($info->{extruding} && $info->{dist_XY} > 0) {
+            if ($tool == $config->support_material_extruder-1) {
+                $raft_z{$self->Z} = 1;
+            }
+        }
+    });
+    
+    is scalar(keys %raft_z), $config->raft_layers, 'correct number of raft layers is generated';
+}
+
 __END__