From f8986d0ef5f1274f36befec411b784d536c8b1b4 Mon Sep 17 00:00:00 2001
From: Alessandro Ranellucci <aar@cpan.org>
Date: Thu, 13 Nov 2014 00:23:31 +0100
Subject: [PATCH] Restore correct behavior for autoarrange after recent commits

---
 lib/Slic3r/GUI/Plater.pm | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/lib/Slic3r/GUI/Plater.pm b/lib/Slic3r/GUI/Plater.pm
index 12391fffb..0900b782b 100644
--- a/lib/Slic3r/GUI/Plater.pm
+++ b/lib/Slic3r/GUI/Plater.pm
@@ -743,15 +743,26 @@ sub changescale {
 sub arrange {
     my $self = shift;
     
+    $self->pause_background_process;
+    
     my $bb = Slic3r::Geometry::BoundingBoxf->new_from_points($self->{config}->bed_shape);
     eval {
         $self->{model}->arrange_objects($self->GetFrame->config->min_object_distance, $bb);
-        $_->reload_model_instances for @{$self->{print}->objects};
     };
     # ignore arrange failures on purpose: user has visual feedback and we don't need to warn him
     # when parts don't fit in print bed
     
     $self->update(1);
+    
+    my $invalidated = 0;
+    foreach my $object (@{$self->{print}->objects}) {
+        $invalidated = 1 if $object->reload_model_instances;
+    }
+    if ($invalidated) {
+        $self->schedule_background_process;
+    } else {
+        $self->resume_background_process;
+    }
     $self->{canvas}->Refresh;
 }