Merge remote-tracking branch 'origin/dev2' into dev_nativeversion_1.42.0-alpha

34 files changed, 1295 insertions, 689 deletions

diff --git a/lib/Slic3r/GUI/Plater.pm b/lib/Slic3r/GUI/Plater.pm
index c4c7224fb..525cc7931 100644
--- a/lib/Slic3r/GUI/Plater.pm
+++ b/lib/Slic3r/GUI/Plater.pm
@@ -150,12 +150,64 @@ sub new {
         $self->rotate(rad2deg($angle), Z, 'absolute');
     };
     
+    # callback to react to gizmo rotate
+    my $on_gizmo_rotate_3D = sub {
+        my ($angle_x, $angle_y, $angle_z) = @_;
+
+        my ($obj_idx, $object) = $self->selected_object;
+        return if !defined $obj_idx;
+
+        my $model_object = $self->{model}->objects->[$obj_idx];
+        my $model_instance = $model_object->instances->[0];
+
+        $self->stop_background_process;
+
+        my $rotation = Slic3r::Pointf3->new($angle_x, $angle_y, $angle_z);
+        foreach my $inst (@{ $model_object->instances }) {
+            $inst->set_rotations($rotation);
+        }
+        Slic3r::GUI::_3DScene::update_gizmos_data($self->{canvas3D}) if ($self->{canvas3D});  
+    
+        # update print and start background processing
+        $self->{print}->add_model_object($model_object, $obj_idx);
+    
+        $self->selection_changed;  # refresh info (size etc.)
+        $self->update;
+        $self->schedule_background_process;
+    };
+    
     # callback to react to gizmo flatten
     my $on_gizmo_flatten = sub {
         my ($angle, $axis_x, $axis_y, $axis_z) = @_;
         $self->rotate(rad2deg($angle), undef, 'absolute', $axis_x, $axis_y, $axis_z) if $angle != 0;
     };
 
+    # callback to react to gizmo flatten
+    my $on_gizmo_flatten_3D = sub {
+        my ($angle_x, $angle_y, $angle_z) = @_;
+
+        my ($obj_idx, $object) = $self->selected_object;
+        return if !defined $obj_idx;
+
+        my $model_object = $self->{model}->objects->[$obj_idx];
+        my $model_instance = $model_object->instances->[0];
+
+        $self->stop_background_process;
+
+        my $rotation = Slic3r::Pointf3->new($angle_x, $angle_y, $angle_z);
+        foreach my $inst (@{ $model_object->instances }) {
+            $inst->set_rotations($rotation);
+        }
+        Slic3r::GUI::_3DScene::update_gizmos_data($self->{canvas3D}) if ($self->{canvas3D});  
+    
+        # update print and start background processing
+        $self->{print}->add_model_object($model_object, $obj_idx);
+    
+        $self->selection_changed;  # refresh info (size etc.)
+        $self->update;
+        $self->schedule_background_process;
+    };
+    
     # callback to update object's geometry info while using gizmos
     my $on_update_geometry_info = sub {
         my ($size_x, $size_y, $size_z, $scale_factor) = @_;
@@ -261,7 +313,9 @@ sub new {
         Slic3r::GUI::_3DScene::register_on_enable_action_buttons_callback($self->{canvas3D}, $enable_action_buttons);
         Slic3r::GUI::_3DScene::register_on_gizmo_scale_uniformly_callback($self->{canvas3D}, $on_gizmo_scale_uniformly);
         Slic3r::GUI::_3DScene::register_on_gizmo_rotate_callback($self->{canvas3D}, $on_gizmo_rotate);
+        Slic3r::GUI::_3DScene::register_on_gizmo_rotate_3D_callback($self->{canvas3D}, $on_gizmo_rotate_3D);
         Slic3r::GUI::_3DScene::register_on_gizmo_flatten_callback($self->{canvas3D}, $on_gizmo_flatten);
+        Slic3r::GUI::_3DScene::register_on_gizmo_flatten_3D_callback($self->{canvas3D}, $on_gizmo_flatten_3D);
         Slic3r::GUI::_3DScene::register_on_update_geometry_info_callback($self->{canvas3D}, $on_update_geometry_info);
         Slic3r::GUI::_3DScene::register_action_add_callback($self->{canvas3D}, $on_action_add);
         Slic3r::GUI::_3DScene::register_action_delete_callback($self->{canvas3D}, $on_action_delete);
diff --git a/slic3r.pl b/slic3r.pl
index 38c10a900..95427443b 100755
--- a/slic3r.pl
+++ b/slic3r.pl
@@ -109,6 +109,7 @@ if ((!@ARGV || $opt{gui}) && !$opt{no_gui} && !$opt{save} && eval "require Slic3
         $Slic3r::GUI::no_plater     = $opt{no_plater};
         $Slic3r::GUI::autosave      = $opt{autosave};
     }
+    Slic3r::GUI::set_gui_appctl();
     $gui = Slic3r::GUI->new;
     #setlocale(LC_NUMERIC, 'C');
     $gui->{mainframe}->load_config_file($_) for @{$opt{load}};
@@ -121,6 +122,9 @@ if ((!@ARGV || $opt{gui}) && !$opt{no_gui} && !$opt{save} && eval "require Slic3
 die $@ if $@ && $opt{gui};
 
 if (@ARGV) {  # slicing from command line
+    Slic3r::GUI::set_cli_appctl();
+    my $appctl = Slic3r::AppController->new();
+
     $config->validate;
     
     if ($opt{repair}) {
@@ -210,7 +214,10 @@ if (@ARGV) {  # slicing from command line
         $sprint->apply_config($config);
         
         if ($opt{export_png}) {
-            $sprint->export_png;
+            # $sprint->export_png;
+            $appctl->set_model($model);
+            $appctl->set_print($sprint->_print);
+            $appctl->print_ctl()->slice_to_png();
         } else {
             my $t0 = [gettimeofday];
             # The following call may die if the output_filename_format template substitution fails,
diff --git a/src/libslic3r/Format/3mf.cpp b/src/libslic3r/Format/3mf.cpp
index c9b4989f5..c4a0f300a 100644
--- a/src/libslic3r/Format/3mf.cpp
+++ b/src/libslic3r/Format/3mf.cpp
@@ -1284,6 +1284,9 @@ namespace Slic3r {
                 transform(1, 0) * inv_sx, transform(1, 1) * inv_sy, transform(1, 2) * inv_sz,
                 transform(2, 0) * inv_sx, transform(2, 1) * inv_sy, transform(2, 2) * inv_sz;
 
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+        Vec3d rotation = m3x3.eulerAngles(0, 1, 2);
+#else
         Eigen::AngleAxisd rotation;
         rotation.fromRotationMatrix(m3x3);
 
@@ -1292,6 +1295,7 @@ namespace Slic3r {
             return;
 
         double angle_z = (rotation.axis() == Vec3d::UnitZ()) ? rotation.angle() : -rotation.angle();
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 
 #if ENABLE_MODELINSTANCE_3D_OFFSET
         instance.set_offset(offset);
@@ -1300,7 +1304,11 @@ namespace Slic3r {
         instance.offset(1) = offset_y;
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
         instance.scaling_factor = sx;
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+        instance.set_rotation(rotation);
+#else
         instance.rotation = angle_z;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
     }
 
     bool _3MF_Importer::_handle_start_config(const char** attributes, unsigned int num_attributes)
diff --git a/src/libslic3r/Format/AMF.cpp b/src/libslic3r/Format/AMF.cpp
index 89a0eacbe..3e0eb54de 100644
--- a/src/libslic3r/Format/AMF.cpp
+++ b/src/libslic3r/Format/AMF.cpp
@@ -30,7 +30,12 @@
 // 0 : .amf, .amf.xml and .zip.amf files saved by older slic3r. No version definition in them.
 // 1 : Introduction of amf versioning. No other change in data saved into amf files.
 #if ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+// 2 : Added z component of offset
+//     Added x and y components of rotation
+#else
 // 2 : Added z component of offset.
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 const unsigned int VERSION_AMF = 2;
 #else
 const unsigned int VERSION_AMF = 1;
@@ -127,6 +132,10 @@ struct AMFParserContext
 #if ENABLE_MODELINSTANCE_3D_OFFSET
         NODE_TYPE_DELTAZ,               // amf/constellation/instance/deltaz
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+        NODE_TYPE_RX,                   // amf/constellation/instance/rx
+        NODE_TYPE_RY,                   // amf/constellation/instance/ry
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
         NODE_TYPE_RZ,                   // amf/constellation/instance/rz
         NODE_TYPE_SCALE,                // amf/constellation/instance/scale
         NODE_TYPE_METADATA,             // anywhere under amf/*/metadata
@@ -134,7 +143,11 @@ struct AMFParserContext
 
     struct Instance {
 #if ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+        Instance() : deltax_set(false), deltay_set(false), deltaz_set(false), rx_set(false), ry_set(false), rz_set(false), scale_set(false) {}
+#else
         Instance() : deltax_set(false), deltay_set(false), deltaz_set(false), rz_set(false), scale_set(false) {}
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 #else
         Instance() : deltax_set(false), deltay_set(false), rz_set(false), scale_set(false) {}
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
@@ -149,6 +162,14 @@ struct AMFParserContext
         float deltaz;
         bool  deltaz_set;
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+        // Rotation around the X axis.
+        float rx;
+        bool  rx_set;
+        // Rotation around the Y axis.
+        float ry;
+        bool  ry_set;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
         // Rotation around the Z axis.
         float rz;
         bool  rz_set;
@@ -275,6 +296,12 @@ void AMFParserContext::startElement(const char *name, const char **atts)
             else if (strcmp(name, "deltaz") == 0)
                 node_type_new = NODE_TYPE_DELTAZ;
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+            else if (strcmp(name, "rx") == 0)
+                node_type_new = NODE_TYPE_RX;
+            else if (strcmp(name, "ry") == 0)
+                node_type_new = NODE_TYPE_RY;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
             else if (strcmp(name, "rz") == 0)
                 node_type_new = NODE_TYPE_RZ;
             else if (strcmp(name, "scale") == 0)
@@ -339,7 +366,11 @@ void AMFParserContext::characters(const XML_Char *s, int len)
             if (m_path.back() == NODE_TYPE_DELTAX || 
                 m_path.back() == NODE_TYPE_DELTAY || 
                 m_path.back() == NODE_TYPE_DELTAZ || 
-                m_path.back() == NODE_TYPE_RZ || 
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+                m_path.back() == NODE_TYPE_RX ||
+                m_path.back() == NODE_TYPE_RY ||
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
+                m_path.back() == NODE_TYPE_RZ ||
                 m_path.back() == NODE_TYPE_SCALE)
 #else
             if (m_path.back() == NODE_TYPE_DELTAX || m_path.back() == NODE_TYPE_DELTAY || m_path.back() == NODE_TYPE_RZ || m_path.back() == NODE_TYPE_SCALE)
@@ -391,6 +422,20 @@ void AMFParserContext::endElement(const char * /* name */)
         m_value[0].clear();
         break;
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    case NODE_TYPE_RX:
+        assert(m_instance);
+        m_instance->rx = float(atof(m_value[0].c_str()));
+        m_instance->rx_set = true;
+        m_value[0].clear();
+        break;
+    case NODE_TYPE_RY:
+        assert(m_instance);
+        m_instance->ry = float(atof(m_value[0].c_str()));
+        m_instance->ry_set = true;
+        m_value[0].clear();
+        break;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
     case NODE_TYPE_RZ:
         assert(m_instance);
         m_instance->rz = float(atof(m_value[0].c_str()));
@@ -542,12 +587,16 @@ void AMFParserContext::endDocument()
             if (instance.deltax_set && instance.deltay_set) {
                 ModelInstance *mi = m_model.objects[object.second.idx]->add_instance();
 #if ENABLE_MODELINSTANCE_3D_OFFSET
-                mi->set_offset(Vec3d((double)instance.deltax, (double)instance.deltay, (double)instance.deltaz));
+                mi->set_offset(Vec3d(instance.deltax_set ? (double)instance.deltax : 0.0, instance.deltay_set ? (double)instance.deltay : 0.0, instance.deltaz_set ? (double)instance.deltaz : 0.0));
 #else
                 mi->offset(0) = instance.deltax;
                 mi->offset(1) = instance.deltay;
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+                mi->set_rotation(Vec3d(instance.rx_set ? (double)instance.rx : 0.0, instance.ry_set ? (double)instance.ry : 0.0, instance.rz_set ? (double)instance.rz : 0.0));
+#else
                 mi->rotation = instance.rz_set ? instance.rz : 0.f;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
                 mi->scaling_factor = instance.scale_set ? instance.scale : 1.f;
             }
     }
@@ -851,6 +900,10 @@ bool store_amf(const char *path, Model *model, Print* print, bool export_print_c
 #if ENABLE_MODELINSTANCE_3D_OFFSET
                     "      <deltaz>%lf</deltaz>\n"
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+                    "      <rx>%lf</rx>\n"
+                    "      <ry>%lf</ry>\n"
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
                     "      <rz>%lf</rz>\n"
                     "      <scale>%lf</scale>\n"
                     "    </instance>\n",
@@ -863,8 +916,15 @@ bool store_amf(const char *path, Model *model, Print* print, bool export_print_c
                     instance->offset(0),
                     instance->offset(1),
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+                    instance->get_rotation(X),
+                    instance->get_rotation(Y),
+                    instance->get_rotation(Z),
+#else
                     instance->rotation,
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
                     instance->scaling_factor);
+
                 //FIXME missing instance->scaling_factor
                 instances.append(buf);
             }
diff --git a/src/libslic3r/Format/PRUS.cpp b/src/libslic3r/Format/PRUS.cpp
index 45eb56c63..27095acef 100644
--- a/src/libslic3r/Format/PRUS.cpp
+++ b/src/libslic3r/Format/PRUS.cpp
@@ -164,7 +164,11 @@ bool load_prus(const char *path, Model *model)
             const char *zero_tag  = "<zero>";
 			const char *zero_xml  = strstr(scene_xml_data.data(), zero_tag);
             float  trafo[3][4] = { 0 };
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+            Vec3d instance_rotation = Vec3d::Zero();
+#else
             double instance_rotation = 0.;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
             double instance_scaling_factor = 1.f;
 #if ENABLE_MODELINSTANCE_3D_OFFSET
             Vec3d instance_offset = Vec3d::Zero();
@@ -197,10 +201,14 @@ bool load_prus(const char *path, Model *model)
                         instance_scaling_factor = scale[0];
                         scale[0] = scale[1] = scale[2] = 1.;
                     }
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+                    instance_rotation = Vec3d(-(double)rotation[0], -(double)rotation[1], -(double)rotation[2]);
+#else
                     if (rotation[0] == 0. && rotation[1] == 0.) {
                         instance_rotation = - rotation[2];
                         rotation[2] = 0.;
                     }
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
                     Eigen::Matrix3f mat_rot, mat_scale, mat_trafo;
                     mat_rot = Eigen::AngleAxisf(-rotation[2], Eigen::Vector3f::UnitZ()) * 
                               Eigen::AngleAxisf(-rotation[1], Eigen::Vector3f::UnitY()) *
@@ -366,8 +374,12 @@ bool load_prus(const char *path, Model *model)
                         model_object = model->add_object(name_utf8.data(), path, std::move(mesh));
                         volume = model_object->volumes.front();
                         ModelInstance *instance     = model_object->add_instance();
-                        instance->rotation          = instance_rotation;
-                        instance->scaling_factor    = instance_scaling_factor;
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+                        instance->set_rotation(instance_rotation);
+#else
+                        instance->rotation = instance_rotation;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
+                        instance->scaling_factor = instance_scaling_factor;
 #if ENABLE_MODELINSTANCE_3D_OFFSET
                         instance->set_offset(instance_offset);
 #else
diff --git a/src/libslic3r/Model.cpp b/src/libslic3r/Model.cpp
index ed705e007..2d23c69b7 100644
--- a/src/libslic3r/Model.cpp
+++ b/src/libslic3r/Model.cpp
@@ -1066,6 +1066,29 @@ size_t ModelVolume::split(unsigned int max_extruders)
     return idx;
 }
 
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+void ModelInstance::set_rotation(const Vec3d& rotation)
+{
+    set_rotation(X, rotation(0));
+    set_rotation(Y, rotation(1));
+    set_rotation(Z, rotation(2));
+}
+
+void ModelInstance::set_rotation(Axis axis, double rotation)
+{
+    static const double TWO_PI = 2.0 * (double)PI;
+    while (rotation < 0.0)
+    {
+        rotation += TWO_PI;
+    }
+    while (TWO_PI < rotation)
+    {
+        rotation -= TWO_PI;
+    }
+    m_rotation(axis) = rotation;
+}
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
+
 void ModelInstance::transform_mesh(TriangleMesh* mesh, bool dont_translate) const
 {
     mesh->transform(world_matrix(dont_translate).cast<float>());
@@ -1110,7 +1133,12 @@ Vec3d ModelInstance::transform_vector(const Vec3d& v, bool dont_translate) const
 
 void ModelInstance::transform_polygon(Polygon* polygon) const
 {
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    // CHECK_ME -> Is the following correct or it should take in account all three rotations ?
+    polygon->rotate(this->m_rotation(2));                // rotate around polygon origin
+#else
     polygon->rotate(this->rotation);                // rotate around polygon origin
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
     polygon->scale(this->scaling_factor);           // scale around polygon origin
 }
 
@@ -1126,7 +1154,15 @@ Transform3d ModelInstance::world_matrix(bool dont_translate, bool dont_rotate, b
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
 
     if (!dont_rotate)
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    {
+        m.rotate(Eigen::AngleAxisd(m_rotation(2), Vec3d::UnitZ()));
+        m.rotate(Eigen::AngleAxisd(m_rotation(1), Vec3d::UnitY()));
+        m.rotate(Eigen::AngleAxisd(m_rotation(0), Vec3d::UnitX()));
+    }
+#else
         m.rotate(Eigen::AngleAxisd(rotation, Vec3d::UnitZ()));
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 
     if (!dont_scale)
         m.scale(scaling_factor);
diff --git a/src/libslic3r/Model.hpp b/src/libslic3r/Model.hpp
index 3acf9b8d2..062efdb85 100644
--- a/src/libslic3r/Model.hpp
+++ b/src/libslic3r/Model.hpp
@@ -248,11 +248,16 @@ public:
 #if ENABLE_MODELINSTANCE_3D_OFFSET
 private:
     Vec3d m_offset;              // in unscaled coordinates
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    Vec3d m_rotation;            // Rotation around the three axes, in radians around mesh center point
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 
 public:
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
 
+#if !ENABLE_MODELINSTANCE_3D_ROTATION
     double rotation;            // Rotation around the Z axis, in radians around mesh center point
+#endif // !ENABLE_MODELINSTANCE_3D_ROTATION
     double scaling_factor;
 #if !ENABLE_MODELINSTANCE_3D_OFFSET
     Vec2d offset;              // in unscaled coordinates
@@ -271,6 +276,14 @@ public:
     void set_offset(Axis axis, double offset) { m_offset(axis) = offset; }
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
 
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    const Vec3d& get_rotation() const { return m_rotation; }
+    double get_rotation(Axis axis) const { return m_rotation(axis); }
+
+    void set_rotation(const Vec3d& rotation);
+    void set_rotation(Axis axis, double rotation);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
+
     // To be called on an external mesh
     void transform_mesh(TriangleMesh* mesh, bool dont_translate = false) const;
     // Calculate a bounding box of a transformed mesh. To be called on an external mesh.
@@ -291,9 +304,15 @@ private:
     ModelObject* object;
 
 #if ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    ModelInstance(ModelObject *object) : m_rotation(Vec3d::Zero()), scaling_factor(1), m_offset(Vec3d::Zero()), object(object), print_volume_state(PVS_Inside) {}
+    ModelInstance(ModelObject *object, const ModelInstance &other) :
+        m_rotation(other.m_rotation), scaling_factor(other.scaling_factor), m_offset(other.m_offset), object(object), print_volume_state(PVS_Inside) {}
+#else
     ModelInstance(ModelObject *object) : rotation(0), scaling_factor(1), m_offset(Vec3d::Zero()), object(object), print_volume_state(PVS_Inside) {}
     ModelInstance(ModelObject *object, const ModelInstance &other) :
         rotation(other.rotation), scaling_factor(other.scaling_factor), m_offset(other.m_offset), object(object), print_volume_state(PVS_Inside) {}
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 #else
     ModelInstance(ModelObject *object) : rotation(0), scaling_factor(1), offset(Vec2d::Zero()), object(object), print_volume_state(PVS_Inside) {}
     ModelInstance(ModelObject *object, const ModelInstance &other) :
diff --git a/src/libslic3r/ModelArrange.hpp b/src/libslic3r/ModelArrange.hpp
index 372689c39..9f983ee9f 100644
--- a/src/libslic3r/ModelArrange.hpp
+++ b/src/libslic3r/ModelArrange.hpp
@@ -292,59 +292,59 @@ protected:
     using Distance = TCoord<PointImpl>;
     using Pile = sl::Shapes<PolygonImpl>;
 
-    Packer pck_;
-    PConfig pconf_; // Placement configuration
-    double bin_area_;
-    SpatIndex rtree_;
-    SpatIndex smallsrtree_;
-    double norm_;
-    Pile merged_pile_;
-    Box pilebb_;
-    ItemGroup remaining_;
-    ItemGroup items_;
+    Packer m_pck;
+    PConfig m_pconf; // Placement configuration
+    double m_bin_area;
+    SpatIndex m_rtree;
+    SpatIndex m_smallsrtree;
+    double m_norm;
+    Pile m_merged_pile;
+    Box m_pilebb;
+    ItemGroup m_remaining;
+    ItemGroup m_items;
 public:
 
     _ArrBase(const TBin& bin, Distance dist,
              std::function<void(unsigned)> progressind,
              std::function<bool(void)> stopcond):
-       pck_(bin, dist), bin_area_(sl::area(bin)),
-       norm_(std::sqrt(sl::area(bin)))
+       m_pck(bin, dist), m_bin_area(sl::area(bin)),
+       m_norm(std::sqrt(sl::area(bin)))
     {
-        fillConfig(pconf_);
+        fillConfig(m_pconf);
 
-        pconf_.before_packing =
+        m_pconf.before_packing =
         [this](const Pile& merged_pile,            // merged pile
                const ItemGroup& items,             // packed items
                const ItemGroup& remaining)         // future items to be packed
         {
-            items_ = items;
-            merged_pile_ = merged_pile;
-            remaining_ = remaining;
+            m_items = items;
+            m_merged_pile = merged_pile;
+            m_remaining = remaining;
 
-            pilebb_ = sl::boundingBox(merged_pile);
+            m_pilebb = sl::boundingBox(merged_pile);
 
-            rtree_.clear();
-            smallsrtree_.clear();
+            m_rtree.clear();
+            m_smallsrtree.clear();
 
             // We will treat big items (compared to the print bed) differently
             auto isBig = [this](double a) {
-                return a/bin_area_ > BIG_ITEM_TRESHOLD ;
+                return a/m_bin_area > BIG_ITEM_TRESHOLD ;
             };
 
             for(unsigned idx = 0; idx < items.size(); ++idx) {
                 Item& itm = items[idx];
-                if(isBig(itm.area())) rtree_.insert({itm.boundingBox(), idx});
-                smallsrtree_.insert({itm.boundingBox(), idx});
+                if(isBig(itm.area())) m_rtree.insert({itm.boundingBox(), idx});
+                m_smallsrtree.insert({itm.boundingBox(), idx});
             }
         };
 
-        pck_.progressIndicator(progressind);
-        pck_.stopCondition(stopcond);
+        m_pck.progressIndicator(progressind);
+        m_pck.stopCondition(stopcond);
     }
 
     template<class...Args> inline IndexedPackGroup operator()(Args&&...args) {
-        rtree_.clear();
-        return pck_.executeIndexed(std::forward<Args>(args)...);
+        m_rtree.clear();
+        return m_pck.executeIndexed(std::forward<Args>(args)...);
     }
 };
 
@@ -358,18 +358,18 @@ public:
         _ArrBase<Box>(bin, dist, progressind, stopcond)
     {
 
-        pconf_.object_function = [this, bin] (const Item &item) {
+        m_pconf.object_function = [this, bin] (const Item &item) {
 
             auto result = objfunc(bin.center(),
-                                  merged_pile_,
-                                  pilebb_,
-                                  items_,
+                                  m_merged_pile,
+                                  m_pilebb,
+                                  m_items,
                                   item,
-                                  bin_area_,
-                                  norm_,
-                                  rtree_,
-                                  smallsrtree_,
-                                  remaining_);
+                                  m_bin_area,
+                                  m_norm,
+                                  m_rtree,
+                                  m_smallsrtree,
+                                  m_remaining);
 
             double score = std::get<0>(result);
             auto& fullbb = std::get<1>(result);
@@ -381,7 +381,7 @@ public:
             return score;
         };
 
-        pck_.configure(pconf_);
+        m_pck.configure(m_pconf);
     }
 };
 
@@ -396,27 +396,27 @@ public:
                  std::function<bool(void)> stopcond):
         _ArrBase<lnCircle>(bin, dist, progressind, stopcond) {
 
-        pconf_.object_function = [this, &bin] (const Item &item) {
+        m_pconf.object_function = [this, &bin] (const Item &item) {
 
             auto result = objfunc(bin.center(),
-                                  merged_pile_,
-                                  pilebb_,
-                                  items_,
+                                  m_merged_pile,
+                                  m_pilebb,
+                                  m_items,
                                   item,
-                                  bin_area_,
-                                  norm_,
-                                  rtree_,
-                                  smallsrtree_,
-                                  remaining_);
+                                  m_bin_area,
+                                  m_norm,
+                                  m_rtree,
+                                  m_smallsrtree,
+                                  m_remaining);
 
             double score = std::get<0>(result);
 
             auto isBig = [this](const Item& itm) {
-                return itm.area()/bin_area_ > BIG_ITEM_TRESHOLD ;
+                return itm.area()/m_bin_area > BIG_ITEM_TRESHOLD ;
             };
 
             if(isBig(item)) {
-                auto mp = merged_pile_;
+                auto mp = m_merged_pile;
                 mp.push_back(item.transformedShape());
                 auto chull = sl::convexHull(mp);
                 double miss = Placer::overfit(chull, bin);
@@ -427,7 +427,7 @@ public:
             return score;
         };
 
-        pck_.configure(pconf_);
+        m_pck.configure(m_pconf);
     }
 };
 
@@ -439,25 +439,25 @@ public:
                  std::function<bool(void)> stopcond):
         _ArrBase<PolygonImpl>(bin, dist, progressind, stopcond)
     {
-        pconf_.object_function = [this, &bin] (const Item &item) {
+        m_pconf.object_function = [this, &bin] (const Item &item) {
 
             auto binbb = sl::boundingBox(bin);
             auto result = objfunc(binbb.center(),
-                                  merged_pile_,
-                                  pilebb_,
-                                  items_,
+                                  m_merged_pile,
+                                  m_pilebb,
+                                  m_items,
                                   item,
-                                  bin_area_,
-                                  norm_,
-                                  rtree_,
-                                  smallsrtree_,
-                                  remaining_);
+                                  m_bin_area,
+                                  m_norm,
+                                  m_rtree,
+                                  m_smallsrtree,
+                                  m_remaining);
             double score = std::get<0>(result);
 
             return score;
         };
 
-        pck_.configure(pconf_);
+        m_pck.configure(m_pconf);
     }
 };
 
@@ -469,22 +469,22 @@ public:
                  std::function<bool(void)> stopcond):
         _ArrBase<Box>(Box(0, 0), dist, progressind, stopcond)
     {
-        this->pconf_.object_function = [this] (const Item &item) {
+        this->m_pconf.object_function = [this] (const Item &item) {
 
             auto result = objfunc({0, 0},
-                                  merged_pile_,
-                                  pilebb_,
-                                  items_,
+                                  m_merged_pile,
+                                  m_pilebb,
+                                  m_items,
                                   item,
                                   0,
-                                  norm_,
-                                  rtree_,
-                                  smallsrtree_,
-                                  remaining_);
+                                  m_norm,
+                                  m_rtree,
+                                  m_smallsrtree,
+                                  m_remaining);
             return std::get<0>(result);
         };
 
-        this->pck_.configure(pconf_);
+        this->m_pck.configure(m_pconf);
     }
 };
 
@@ -527,14 +527,19 @@ ShapeData2D projectModelFromTop(const Slic3r::Model &model) {
 
                     // Invalid geometries would throw exceptions when arranging
                     if(item.vertexCount() > 3) {
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+                        // CHECK_ME -> is the following correct or it should take in account all three rotations ?
+                        item.rotation(objinst->get_rotation(Z));
+#else
                         item.rotation(objinst->rotation);
-                        item.translation( {
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
+                        item.translation({
 #if ENABLE_MODELINSTANCE_3D_OFFSET
-                            ClipperLib::cInt(objinst->get_offset(X) / SCALING_FACTOR),
-                            ClipperLib::cInt(objinst->get_offset(Y) / SCALING_FACTOR)
+                        ClipperLib::cInt(objinst->get_offset(X)/SCALING_FACTOR),
+                        ClipperLib::cInt(objinst->get_offset(Y)/SCALING_FACTOR)
 #else
-                            ClipperLib::cInt(objinst->offset(0)/SCALING_FACTOR),
-                            ClipperLib::cInt(objinst->offset(1)/SCALING_FACTOR)
+                        ClipperLib::cInt(objinst->offset(0)/SCALING_FACTOR),
+                        ClipperLib::cInt(objinst->offset(1)/SCALING_FACTOR)
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
                         });
                         ret.emplace_back(objinst, item);
@@ -668,18 +673,25 @@ void applyResult(
         // Get the model instance from the shapemap using the index
         ModelInstance *inst_ptr = shapemap[idx].first;
 
-        // Get the tranformation data from the item object and scale it
+        // Get the transformation data from the item object and scale it
         // appropriately
         auto off = item.translation();
         Radians rot = item.rotation();
 #if ENABLE_MODELINSTANCE_3D_OFFSET
-        Vec3d foff(off.X*SCALING_FACTOR + batch_offset, off.Y*SCALING_FACTOR, 0.0);
+        Vec3d foff(off.X*SCALING_FACTOR + batch_offset,
+                   off.Y*SCALING_FACTOR,
+                   0.0);
 #else
         Vec2d foff(off.X*SCALING_FACTOR + batch_offset, off.Y*SCALING_FACTOR);
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
 
-        // write the tranformation data into the model instance
+        // write the transformation data into the model instance
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+        // CHECK_ME -> Is the following correct ?
+        inst_ptr->set_rotation(Vec3d(0.0, 0.0, rot));
+#else
         inst_ptr->rotation = rot;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 #if ENABLE_MODELINSTANCE_3D_OFFSET
         inst_ptr->set_offset(foff);
 #else
@@ -695,7 +707,7 @@ void applyResult(
  * The arrangement considers multiple bins (aka. print beds) for placing all
  * the items provided in the model argument. If the items don't fit on one
  * print bed, the remaining will be placed onto newly created print beds.
- * The first_bin_only parameter, if set to true, disables this behaviour and
+ * The first_bin_only parameter, if set to true, disables this behavior and
  * makes sure that only one print bed is filled and the remaining items will be
  * untouched. When set to false, the items which could not fit onto the
  * print bed will be placed next to the print bed so the user should see a
@@ -741,6 +753,7 @@ bool arrange(Model &model, coordf_t min_obj_distance,
 
     IndexedPackGroup result;
 
+    // If there is no hint about the shape, we will try to guess
     if(bedhint.type == BedShapeType::WHO_KNOWS) bedhint = bedShape(bed);
 
     BoundingBox bbb(bed);
diff --git a/src/libslic3r/PrintExport.hpp b/src/libslic3r/PrintExport.hpp
index c3c59fc30..917a39e08 100644
--- a/src/libslic3r/PrintExport.hpp
+++ b/src/libslic3r/PrintExport.hpp
@@ -32,10 +32,10 @@ template<FilePrinterFormat format, class LayerFormat = void>
 class FilePrinter {
 public:
 
-    void printConfig(const Print&);
+    void print_config(const Print&);
 
     // Draw an ExPolygon which is a polygon inside a slice on the specified layer.
-    void drawPolygon(const ExPolygon& p, unsigned lyr);
+    void draw_polygon(const ExPolygon& p, unsigned lyr);
 
     // Tell the printer how many layers should it consider.
     void layers(unsigned layernum);
@@ -47,45 +47,47 @@ public:
      * specified layer number than an appropriate number of layers will be
      * allocated in the printer.
      */
-    void beginLayer(unsigned layer);
+    void begin_layer(unsigned layer);
 
     // Allocate a new layer on top of the last and switch to it.
-    void beginLayer();
+    void begin_layer();
 
     /*
      * Finish the selected layer. It means that no drawing is allowed on that
      * layer anymore. This fact can be used to prepare the file system output
      * data like png comprimation and so on.
      */
-    void finishLayer(unsigned layer);
+    void finish_layer(unsigned layer);
 
     // Finish the top layer.
-    void finishLayer();
+    void finish_layer();
 
     // Save all the layers into the file (or dir) specified in the path argument
     void save(const std::string& path);
 
     // Save only the selected layer to the file specified in path argument.
-    void saveLayer(unsigned lyr, const std::string& path);
+    void save_layer(unsigned lyr, const std::string& path);
 };
 
 template<class T = void> struct VeryFalse { static const bool value = false; };
 
 // This has to be explicitly implemented in the gui layer or a default zlib
 // based implementation is needed.
-template<class Backend> class Zipper {
+template<class Backend> class LayerWriter {
 public:
 
-    Zipper(const std::string& /*zipfile_path*/) {
+    LayerWriter(const std::string& /*zipfile_path*/) {
         static_assert(VeryFalse<Backend>::value,
-                      "No zipper implementation provided!");
+                      "No layer writer implementation provided!");
     }
 
     void next_entry(const std::string& /*fname*/) {}
 
     std::string get_name() { return ""; }
 
-    template<class T> Zipper& operator<<(const T& /*arg*/) {
+    bool is_ok() { return false; }
+
+    template<class T> LayerWriter& operator<<(const T& /*arg*/) {
         return *this;
     }
 
@@ -110,22 +112,22 @@ template<class LyrFormat> class FilePrinter<FilePrinterFormat::PNG, LyrFormat> {
 
     // We will save the compressed PNG data into stringstreams which can be done
     // in parallel. Later we can write every layer to the disk sequentially.
-    std::vector<Layer> layers_rst_;
-    Raster::Resolution res_;
-    Raster::PixelDim pxdim_;
-    const Print *print_ = nullptr;
-    double exp_time_s_ = .0, exp_time_first_s_ = .0;
+    std::vector<Layer> m_layers_rst;
+    Raster::Resolution m_res;
+    Raster::PixelDim m_pxdim;
+    const Print *m_print = nullptr;
+    double m_exp_time_s = .0, m_exp_time_first_s = .0;
 
     std::string createIniContent(const std::string& projectname) {
-        double layer_height = print_?
-                    print_->default_object_config().layer_height.getFloat() :
+        double layer_height = m_print?
+                    m_print->default_object_config().layer_height.getFloat() :
                     0.05;
 
         using std::string;
         using std::to_string;
 
-        auto expt_str = to_string(exp_time_s_);
-        auto expt_first_str = to_string(exp_time_first_s_);
+        auto expt_str = to_string(m_exp_time_s);
+        auto expt_first_str = to_string(m_exp_time_first_s);
         auto stepnum_str = to_string(static_cast<unsigned>(800*layer_height));
         auto layerh_str = to_string(layer_height);
 
@@ -153,117 +155,84 @@ public:
     inline FilePrinter(double width_mm, double height_mm,
                        unsigned width_px, unsigned height_px,
                        double exp_time, double exp_time_first):
-        res_(width_px, height_px),
-        pxdim_(width_mm/width_px, height_mm/height_px),
-        exp_time_s_(exp_time),
-        exp_time_first_s_(exp_time_first)
+        m_res(width_px, height_px),
+        m_pxdim(width_mm/width_px, height_mm/height_px),
+        m_exp_time_s(exp_time),
+        m_exp_time_first_s(exp_time_first)
     {
     }
 
     FilePrinter(const FilePrinter& ) = delete;
     FilePrinter(FilePrinter&& m):
-        layers_rst_(std::move(m.layers_rst_)),
-        res_(m.res_),
-        pxdim_(m.pxdim_) {}
+        m_layers_rst(std::move(m.m_layers_rst)),
+        m_res(m.m_res),
+        m_pxdim(m.m_pxdim) {}
 
-    inline void layers(unsigned cnt) { if(cnt > 0) layers_rst_.resize(cnt); }
-    inline unsigned layers() const { return unsigned(layers_rst_.size()); }
+    inline void layers(unsigned cnt) { if(cnt > 0) m_layers_rst.resize(cnt); }
+    inline unsigned layers() const { return unsigned(m_layers_rst.size()); }
 
-    void printConfig(const Print& printconf) { print_ = &printconf; }
+    void print_config(const Print& printconf) { m_print = &printconf; }
 
-    inline void drawPolygon(const ExPolygon& p, unsigned lyr) {
-        assert(lyr < layers_rst_.size());
-        layers_rst_[lyr].first.draw(p);
+    inline void draw_polygon(const ExPolygon& p, unsigned lyr) {
+        assert(lyr < m_layers_rst.size());
+        m_layers_rst[lyr].first.draw(p);
     }
 
-    inline void beginLayer(unsigned lyr) {
-        if(layers_rst_.size() <= lyr) layers_rst_.resize(lyr+1);
-        layers_rst_[lyr].first.reset(res_, pxdim_, ORIGIN);
+    inline void begin_layer(unsigned lyr) {
+        if(m_layers_rst.size() <= lyr) m_layers_rst.resize(lyr+1);
+        m_layers_rst[lyr].first.reset(m_res, m_pxdim, ORIGIN);
     }
 
-    inline void beginLayer() {
-        layers_rst_.emplace_back();
-        layers_rst_.front().first.reset(res_, pxdim_, ORIGIN);
+    inline void begin_layer() {
+        m_layers_rst.emplace_back();
+        m_layers_rst.front().first.reset(m_res, m_pxdim, ORIGIN);
     }
 
-    inline void finishLayer(unsigned lyr_id) {
-        assert(lyr_id < layers_rst_.size());
-        layers_rst_[lyr_id].first.save(layers_rst_[lyr_id].second,
+    inline void finish_layer(unsigned lyr_id) {
+        assert(lyr_id < m_layers_rst.size());
+        m_layers_rst[lyr_id].first.save(m_layers_rst[lyr_id].second,
                                        Raster::Compression::PNG);
-        layers_rst_[lyr_id].first.reset();
+        m_layers_rst[lyr_id].first.reset();
     }
 
-    inline void finishLayer() {
-        if(!layers_rst_.empty()) {
-            layers_rst_.back().first.save(layers_rst_.back().second,
+    inline void finish_layer() {
+        if(!m_layers_rst.empty()) {
+            m_layers_rst.back().first.save(m_layers_rst.back().second,
                                           Raster::Compression::PNG);
-            layers_rst_.back().first.reset();
+            m_layers_rst.back().first.reset();
         }
     }
 
     inline void save(const std::string& path) {
         try {
-            Zipper<LyrFormat> zipper(path);
+            LayerWriter<LyrFormat> writer(path);
 
-            std::string project = zipper.get_name();
+            std::string project = writer.get_name();
 
-            zipper.next_entry(project);
-            zipper << createIniContent(project);
+            writer.next_entry("config.ini");
+            writer << createIniContent(project);
 
-            for(unsigned i = 0; i < layers_rst_.size(); i++) {
-                if(layers_rst_[i].second.rdbuf()->in_avail() > 0) {
+            for(unsigned i = 0; i < m_layers_rst.size(); i++) {
+                if(m_layers_rst[i].second.rdbuf()->in_avail() > 0) {
                     char lyrnum[6];
                     std::sprintf(lyrnum, "%.5d", i);
                     auto zfilename = project + lyrnum + ".png";
-                    zipper.next_entry(zfilename);
-                    zipper << layers_rst_[i].second.rdbuf();
-                    layers_rst_[i].second.str("");
+                    writer.next_entry(zfilename);
+                    writer << m_layers_rst[i].second.rdbuf();
+                    m_layers_rst[i].second.str("");
                 }
             }
 
-            zipper.close();
-        } catch(std::exception&) {
-            BOOST_LOG_TRIVIAL(error) << "Can't create zip file for layers! "
-                                     << path;
+            writer.close();
+        } catch(std::exception& e) {
+            BOOST_LOG_TRIVIAL(error) << e.what();
             return;
         }
-
-//        wxFileName filepath(path);
-
-//        wxFFileOutputStream zipfile(path);
-
-//        std::string project = filepath.GetName().ToStdString();
-
-//        if(!zipfile.IsOk()) {
-//            BOOST_LOG_TRIVIAL(error) << "Can't create zip file for layers! "
-//                                     << path;
-//            return;
-//        }
-
-//        wxZipOutputStream zipstream(zipfile);
-//        wxStdOutputStream pngstream(zipstream);
-
-//        zipstream.PutNextEntry("config.ini");
-//        pngstream << createIniContent(project);
-
-//        for(unsigned i = 0; i < layers_rst_.size(); i++) {
-//            if(layers_rst_[i].second.rdbuf()->in_avail() > 0) {
-//                char lyrnum[6];
-//                std::sprintf(lyrnum, "%.5d", i);
-//                auto zfilename = project + lyrnum + ".png";
-//                zipstream.PutNextEntry(zfilename);
-//                pngstream << layers_rst_[i].second.rdbuf();
-//                layers_rst_[i].second.str("");
-//            }
-//        }
-
-//        zipstream.Close();
-//        zipfile.Close();
     }
 
-    void saveLayer(unsigned lyr, const std::string& path) {
+    void save_layer(unsigned lyr, const std::string& path) {
         unsigned i = lyr;
-        assert(i < layers_rst_.size());
+        assert(i < m_layers_rst.size());
 
         char lyrnum[6];
         std::sprintf(lyrnum, "%.5d", lyr);
@@ -271,19 +240,19 @@ public:
 
         std::fstream out(loc, std::fstream::out | std::fstream::binary);
         if(out.good()) {
-            layers_rst_[i].first.save(out, Raster::Compression::PNG);
+            m_layers_rst[i].first.save(out, Raster::Compression::PNG);
         } else {
             BOOST_LOG_TRIVIAL(error) << "Can't create file for layer";
         }
 
         out.close();
-        layers_rst_[i].first.reset();
+        m_layers_rst[i].first.reset();
     }
 };
 
 // Let's shadow this eigen interface
-inline coord_t px(const Point& p) { return p(0); }
-inline coord_t py(const Point& p) { return p(1); }
+inline coord_t  px(const Point& p) { return p(0); }
+inline coord_t  py(const Point& p) { return p(1); }
 inline coordf_t px(const Vec2d& p) { return p(0); }
 inline coordf_t py(const Vec2d& p) { return p(1); }
 
@@ -337,7 +306,7 @@ void print_to(Print& print,
     FilePrinter<format, LayerFormat> printer(width_mm, height_mm,
                                              std::forward<Args>(args)...);
 
-    printer.printConfig(print);
+    printer.print_config(print);
 
     printer.layers(layers.size());  // Allocate space for all the layers
 
@@ -358,7 +327,7 @@ void print_to(Print& print,
     {
         LayerPtrs lrange = layers[keys[layer_id]];
 
-        printer.beginLayer(layer_id);   // Switch to the appropriate layer
+        printer.begin_layer(layer_id);   // Switch to the appropriate layer
 
         for(Layer *lp : lrange) {
             Layer& l = *lp;
@@ -379,7 +348,7 @@ void print_to(Print& print,
                     slice.translate(-px(print_bb.min) + cx,
                                     -py(print_bb.min) + cy);
 
-                    printer.drawPolygon(slice, layer_id);
+                    printer.draw_polygon(slice, layer_id);
                 }
 
             /*if(print.has_support_material() && layer_id > 0) {
@@ -392,7 +361,7 @@ void print_to(Print& print,
 
         }
 
-        printer.finishLayer(layer_id);  // Finish the layer for later saving it.
+        printer.finish_layer(layer_id);  // Finish the layer for later saving it.
 
         auto st = static_cast<int>(layer_id*80.0/layers.size());
         m.lock();
diff --git a/src/libslic3r/Rasterizer/Rasterizer.cpp b/src/libslic3r/Rasterizer/Rasterizer.cpp
index b0bf04343..3ff3e0949 100644
--- a/src/libslic3r/Rasterizer/Rasterizer.cpp
+++ b/src/libslic3r/Rasterizer/Rasterizer.cpp
@@ -37,37 +37,37 @@ public:
     using Origin = Raster::Origin;
 
 private:
-    Raster::Resolution resolution_;
-    Raster::PixelDim pxdim_;
-    TBuffer buf_;
-    TRawBuffer rbuf_;
-    TPixelRenderer pixfmt_;
-    TRawRenderer raw_renderer_;
-    TRendererAA renderer_;
-    Origin o_;
-    std::function<void(agg::path_storage&)> flipy_ = [](agg::path_storage&) {};
+    Raster::Resolution m_resolution;
+    Raster::PixelDim m_pxdim;
+    TBuffer m_buf;
+    TRawBuffer m_rbuf;
+    TPixelRenderer m_pixfmt;
+    TRawRenderer m_raw_renderer;
+    TRendererAA m_renderer;
+    Origin m_o;
+    std::function<void(agg::path_storage&)> m_flipy = [](agg::path_storage&) {};
 public:
     inline Impl(const Raster::Resolution& res, const Raster::PixelDim &pd,
                 Origin o):
-        resolution_(res), pxdim_(pd),
-        buf_(res.pixels()),
-        rbuf_(reinterpret_cast<TPixelRenderer::value_type*>(buf_.data()),
+        m_resolution(res), m_pxdim(pd),
+        m_buf(res.pixels()),
+        m_rbuf(reinterpret_cast<TPixelRenderer::value_type*>(m_buf.data()),
               res.width_px, res.height_px,
               res.width_px*TPixelRenderer::num_components),
-        pixfmt_(rbuf_),
-        raw_renderer_(pixfmt_),
-        renderer_(raw_renderer_),
-        o_(o)
+        m_pixfmt(m_rbuf),
+        m_raw_renderer(m_pixfmt),
+        m_renderer(m_raw_renderer),
+        m_o(o)
     {
-        renderer_.color(ColorWhite);
+        m_renderer.color(ColorWhite);
 
         // If we would like to play around with gamma
         // ras.gamma(agg::gamma_power(1.0));
 
         clear();
 
-        if(o_ == Origin::TOP_LEFT) flipy_ = [this](agg::path_storage& path) {
-            path.flip_y(0, resolution_.height_px);
+        if(m_o == Origin::TOP_LEFT) m_flipy = [this](agg::path_storage& path) {
+            path.flip_y(0, m_resolution.height_px);
         };
     }
 
@@ -76,35 +76,35 @@ public:
         agg::scanline_p8 scanlines;
 
         auto&& path = to_path(poly.contour);
-        flipy_(path);
+        m_flipy(path);
         ras.add_path(path);
 
         for(auto h : poly.holes) {
             auto&& holepath = to_path(h);
-            flipy_(holepath);
+            m_flipy(holepath);
             ras.add_path(holepath);
         }
 
-        agg::render_scanlines(ras, scanlines, renderer_);
+        agg::render_scanlines(ras, scanlines, m_renderer);
     }
 
     inline void clear() {
-        raw_renderer_.clear(ColorBlack);
+        m_raw_renderer.clear(ColorBlack);
     }
 
-    inline TBuffer& buffer()  { return buf_; }
+    inline TBuffer& buffer()  { return m_buf; }
 
-    inline const Raster::Resolution resolution() { return resolution_; }
+    inline const Raster::Resolution resolution() { return m_resolution; }
 
-    inline Origin origin() const /*noexcept*/ { return o_; }
+    inline Origin origin() const /*noexcept*/ { return m_o; }
 
 private:
     double getPx(const Point& p) {
-        return p(0) * SCALING_FACTOR/pxdim_.w_mm;
+        return p(0) * SCALING_FACTOR/m_pxdim.w_mm;
     }
 
     double getPy(const Point& p) {
-        return p(1) * SCALING_FACTOR/pxdim_.h_mm;
+        return p(1) * SCALING_FACTOR/m_pxdim.h_mm;
     }
 
     agg::path_storage to_path(const Polygon& poly) {
@@ -124,57 +124,57 @@ const Raster::Impl::TPixel Raster::Impl::ColorWhite = Raster::Impl::TPixel(255);
 const Raster::Impl::TPixel Raster::Impl::ColorBlack = Raster::Impl::TPixel(0);
 
 Raster::Raster(const Resolution &r, const PixelDim &pd, Origin o):
-    impl_(new Impl(r, pd, o)) {}
+    m_impl(new Impl(r, pd, o)) {}
 
 Raster::Raster() {}
 
 Raster::~Raster() {}
 
 Raster::Raster(Raster &&m):
-    impl_(std::move(m.impl_)) {}
+    m_impl(std::move(m.m_impl)) {}
 
 void Raster::reset(const Raster::Resolution &r, const Raster::PixelDim &pd)
 {
     // Free up the unnecessary memory and make sure it stays clear after
     // an exception
-    auto o = impl_? impl_->origin() : Origin::TOP_LEFT;
+    auto o = m_impl? m_impl->origin() : Origin::TOP_LEFT;
     reset(r, pd, o);
 }
 
 void Raster::reset(const Raster::Resolution &r, const Raster::PixelDim &pd,
                    Raster::Origin o)
 {
-    impl_.reset();
-    impl_.reset(new Impl(r, pd, o));
+    m_impl.reset();
+    m_impl.reset(new Impl(r, pd, o));
 }
 
 void Raster::reset()
 {
-    impl_.reset();
+    m_impl.reset();
 }
 
 Raster::Resolution Raster::resolution() const
 {
-    if(impl_) return impl_->resolution();
+    if(m_impl) return m_impl->resolution();
 
     return Resolution(0, 0);
 }
 
 void Raster::clear()
 {
-    assert(impl_);
-    impl_->clear();
+    assert(m_impl);
+    m_impl->clear();
 }
 
 void Raster::draw(const ExPolygon &poly)
 {
-    assert(impl_);
-    impl_->draw(poly);
+    assert(m_impl);
+    m_impl->draw(poly);
 }
 
 void Raster::save(std::ostream& stream, Compression comp)
 {
-    assert(impl_);
+    assert(m_impl);
     switch(comp) {
     case Compression::PNG: {
 
@@ -188,7 +188,7 @@ void Raster::save(std::ostream& stream, Compression comp)
 
         wr.write_info();
 
-        auto& b = impl_->buffer();
+        auto& b = m_impl->buffer();
         auto ptr = reinterpret_cast<png::byte*>( b.data() );
         unsigned stride =
                 sizeof(Impl::TBuffer::value_type) *  resolution().width_px;
@@ -201,12 +201,12 @@ void Raster::save(std::ostream& stream, Compression comp)
     }
     case Compression::RAW: {
         stream << "P5 "
-               << impl_->resolution().width_px << " "
-               << impl_->resolution().height_px << " "
+               << m_impl->resolution().width_px << " "
+               << m_impl->resolution().height_px << " "
                << "255 ";
 
-        stream.write(reinterpret_cast<const char*>(impl_->buffer().data()),
-                     impl_->buffer().size()*sizeof(Impl::TBuffer::value_type));
+        stream.write(reinterpret_cast<const char*>(m_impl->buffer().data()),
+                     m_impl->buffer().size()*sizeof(Impl::TBuffer::value_type));
     }
     }
 }
diff --git a/src/libslic3r/Rasterizer/Rasterizer.hpp b/src/libslic3r/Rasterizer/Rasterizer.hpp
index cbb39bc6b..b6406b770 100644
--- a/src/libslic3r/Rasterizer/Rasterizer.hpp
+++ b/src/libslic3r/Rasterizer/Rasterizer.hpp
@@ -18,7 +18,7 @@ class ExPolygon;
  */
 class Raster {
     class Impl;
-    std::unique_ptr<Impl> impl_;
+    std::unique_ptr<Impl> m_impl;
 public:
 
     /// Supported compression types
@@ -65,7 +65,7 @@ public:
 
     /**
      * Release the allocated resources. Drawing in this state ends in
-     * unspecified behaviour.
+     * unspecified behavior.
      */
     void reset();
 
diff --git a/src/libslic3r/Technologies.hpp b/src/libslic3r/Technologies.hpp
index 5c4f8617d..25e6b85e7 100644
--- a/src/libslic3r/Technologies.hpp
+++ b/src/libslic3r/Technologies.hpp
@@ -6,6 +6,10 @@
 
 // Add z coordinate to model instances' offset
 #define ENABLE_MODELINSTANCE_3D_OFFSET (1 && ENABLE_1_42_0)
+// Add double click on gizmo grabbers to reset transformation components to their default value
+#define ENABLE_GIZMOS_RESET (1 && ENABLE_1_42_0)
+// Add x and y rotation components to model instances' offset
+#define ENABLE_MODELINSTANCE_3D_ROTATION (1 && ENABLE_MODELINSTANCE_3D_OFFSET)
 
 #endif // _technologies_h_
 
diff --git a/src/slic3r/AppController.cpp b/src/slic3r/AppController.cpp
index 6728c6c00..2bb79cec1 100644
--- a/src/slic3r/AppController.cpp
+++ b/src/slic3r/AppController.cpp
@@ -18,13 +18,10 @@
 #include <Model.hpp>
 #include <Utils.hpp>
 
-#include <wx/stdstream.h>
-#include <wx/wfstream.h>
-#include <wx/zipstrm.h>
 
 namespace Slic3r {
 
-class AppControllerBoilerplate::PriData {
+class AppControllerGui::PriData {
 public:
     std::mutex m;
     std::thread::id ui_thread;
@@ -32,16 +29,16 @@ public:
     inline explicit PriData(std::thread::id uit): ui_thread(uit) {}
 };
 
-AppControllerBoilerplate::AppControllerBoilerplate()
-    :pri_data_(new PriData(std::this_thread::get_id())) {}
+AppControllerGui::AppControllerGui()
+    :m_pri_data(new PriData(std::this_thread::get_id())) {}
 
-AppControllerBoilerplate::~AppControllerBoilerplate() {
-    pri_data_.reset();
+AppControllerGui::~AppControllerGui() {
+    m_pri_data.reset();
 }
 
-bool AppControllerBoilerplate::is_main_thread() const
+bool AppControllerGui::is_main_thread() const
 {
-    return pri_data_->ui_thread == std::this_thread::get_id();
+    return m_pri_data->ui_thread == std::this_thread::get_id();
 }
 
 namespace GUI {
@@ -57,172 +54,32 @@ static const PrintStep STEP_SKIRT                       = psSkirt;
 static const PrintStep STEP_BRIM                        = psBrim;
 static const PrintStep STEP_WIPE_TOWER                  = psWipeTower;
 
-AppControllerBoilerplate::ProgresIndicatorPtr
-AppControllerBoilerplate::global_progress_indicator() {
+ProgresIndicatorPtr AppControllerGui::global_progress_indicator() {
     ProgresIndicatorPtr ret;
 
-    pri_data_->m.lock();
-    ret = global_progressind_;
-    pri_data_->m.unlock();
+    m_pri_data->m.lock();
+    ret = m_global_progressind;
+    m_pri_data->m.unlock();
 
     return ret;
 }
 
-void AppControllerBoilerplate::global_progress_indicator(
-        AppControllerBoilerplate::ProgresIndicatorPtr gpri)
+void AppControllerGui::global_progress_indicator(ProgresIndicatorPtr gpri)
 {
-    pri_data_->m.lock();
-    global_progressind_ = gpri;
-    pri_data_->m.unlock();
+    m_pri_data->m.lock();
+    m_global_progressind = gpri;
+    m_pri_data->m.unlock();
 }
 
-//void PrintController::make_skirt()
-//{
-//    assert(print_ != nullptr);
-
-//    // prerequisites
-//    for(auto obj : print_->objects) make_perimeters(obj);
-//    for(auto obj : print_->objects) infill(obj);
-//    for(auto obj : print_->objects) gen_support_material(obj);
-
-//    if(!print_->state.is_done(STEP_SKIRT)) {
-//        print_->state.set_started(STEP_SKIRT);
-//        print_->skirt.clear();
-//        if(print_->has_skirt()) print_->_make_skirt();
-
-//        print_->state.set_done(STEP_SKIRT);
-//    }
-//}
-
-//void PrintController::make_brim()
-//{
-//    assert(print_ != nullptr);
-
-//    // prerequisites
-//    for(auto obj : print_->objects) make_perimeters(obj);
-//    for(auto obj : print_->objects) infill(obj);
-//    for(auto obj : print_->objects) gen_support_material(obj);
-//    make_skirt();
-
-//    if(!print_->state.is_done(STEP_BRIM)) {
-//        print_->state.set_started(STEP_BRIM);
-
-//        // since this method must be idempotent, we clear brim paths *before*
-//        // checking whether we need to generate them
-//        print_->brim.clear();
-
-//        if(print_->config.brim_width > 0) print_->_make_brim();
-
-//        print_->state.set_done(STEP_BRIM);
-//    }
-//}
-
-//void PrintController::make_wipe_tower()
-//{
-//    assert(print_ != nullptr);
-
-//    // prerequisites
-//    for(auto obj : print_->objects) make_perimeters(obj);
-//    for(auto obj : print_->objects) infill(obj);
-//    for(auto obj : print_->objects) gen_support_material(obj);
-//    make_skirt();
-//    make_brim();
-
-//    if(!print_->state.is_done(STEP_WIPE_TOWER)) {
-//        print_->state.set_started(STEP_WIPE_TOWER);
-
-//        // since this method must be idempotent, we clear brim paths *before*
-//        // checking whether we need to generate them
-//        print_->brim.clear();
-
-//        if(print_->has_wipe_tower()) print_->_make_wipe_tower();
-
-//        print_->state.set_done(STEP_WIPE_TOWER);
-//    }
-//}
-
-//void PrintController::slice(PrintObject *pobj)
-//{
-//    assert(pobj != nullptr && print_ != nullptr);
-
-//    if(pobj->state.is_done(STEP_SLICE)) return;
-
-//    pobj->state.set_started(STEP_SLICE);
-
-//    pobj->_slice();
-
-//    auto msg = pobj->_fix_slicing_errors();
-//    if(!msg.empty()) report_issue(IssueType::WARN, msg);
-
-//    // simplify slices if required
-//    if (print_->config.resolution)
-//        pobj->_simplify_slices(scale_(print_->config.resolution));
-
-
-//    if(pobj->layers.empty())
-//        report_issue(IssueType::ERR,
-//                     L("No layers were detected. You might want to repair your "
-//                     "STL file(s) or check their size or thickness and retry")
-//                     );
-
-//    pobj->state.set_done(STEP_SLICE);
-//}
-
-//void PrintController::make_perimeters(PrintObject *pobj)
-//{
-//    assert(pobj != nullptr);
-
-//    slice(pobj);
-
-//    if (!pobj->state.is_done(STEP_PERIMETERS)) {
-//        pobj->_make_perimeters();
-//    }
-//}
-
-//void PrintController::infill(PrintObject *pobj)
-//{
-//    assert(pobj != nullptr);
-
-//    make_perimeters(pobj);
-
-//    if (!pobj->state.is_done(STEP_PREPARE_INFILL)) {
-//        pobj->state.set_started(STEP_PREPARE_INFILL);
-
-//        pobj->_prepare_infill();
-
-//        pobj->state.set_done(STEP_PREPARE_INFILL);
-//    }
-
-//    pobj->_infill();
-//}
-
-//void PrintController::gen_support_material(PrintObject *pobj)
-//{
-//    assert(pobj != nullptr);
-
-//    // prerequisites
-//    slice(pobj);
-
-//    if(!pobj->state.is_done(STEP_SUPPORTMATERIAL)) {
-//        pobj->state.set_started(STEP_SUPPORTMATERIAL);
-
-//        pobj->clear_support_layers();
-
-//        if((pobj->config.support_material || pobj->config.raft_layers > 0)
-//                && pobj->layers.size() > 1) {
-//            pobj->_generate_support_material();
-//        }
-
-//        pobj->state.set_done(STEP_SUPPORTMATERIAL);
-//    }
-//}
-
 PrintController::PngExportData
 PrintController::query_png_export_data(const DynamicPrintConfig& conf)
 {
     PngExportData ret;
 
-    auto zippath = query_destination_path("Output zip file", "*.zip", "out");
+    auto c = GUI::get_appctl();
+    auto zippath = c->query_destination_path("Output zip file", "*.zip",
+                                             "export-png",
+                                             "out");
 
     ret.zippath = zippath;
 
@@ -246,98 +103,53 @@ PrintController::query_png_export_data(const DynamicPrintConfig& conf)
     return ret;
 }
 
-void PrintController::slice(AppControllerBoilerplate::ProgresIndicatorPtr pri)
+void PrintController::slice(ProgresIndicatorPtr pri)
 {
-    auto st = pri->state();
-
-    Slic3r::trace(3, "Starting the slicing process.");
-
-    pri->update(st+20, L("Generating perimeters"));
-//    for(auto obj : print_->objects) make_perimeters(obj);
-
-    pri->update(st+60, L("Infilling layers"));
-//    for(auto obj : print_->objects) infill(obj);
-
-    pri->update(st+70, L("Generating support material"));
-//    for(auto obj : print_->objects) gen_support_material(obj);
-
-//    pri->message_fmt(L("Weight: %.1fg, Cost: %.1f"),
-//                     print_->total_weight, print_->total_cost);
-    pri->state(st+85);
-
-
-    pri->update(st+88, L("Generating skirt"));
-    make_skirt();
-
-
-    pri->update(st+90, L("Generating brim"));
-    make_brim();
-
-    pri->update(st+95, L("Generating wipe tower"));
-    make_wipe_tower();
-
-    pri->update(st+100, L("Done"));
-
-    // time to make some statistics..
+    m_print->set_status_callback([pri](int st, const std::string& msg){
+        pri->update(unsigned(st), msg);
+    });
 
-    Slic3r::trace(3, L("Slicing process finished."));
+    m_print->process();
 }
 
 void PrintController::slice()
 {
-    auto pri = global_progress_indicator();
-    if(!pri) pri = create_progress_indicator(100, L("Slicing"));
+    auto ctl = GUI::get_appctl();
+    auto pri = ctl->global_progress_indicator();
+    if(!pri) pri = ctl->create_progress_indicator(100, L("Slicing"));
     slice(pri);
 }
 
-struct wxZipper {};
-
-template<> class Zipper<wxZipper> {
-    wxFileName m_fpath;
-    wxFFileOutputStream m_zipfile;
-    wxZipOutputStream m_zipstream;
-    wxStdOutputStream m_pngstream;
+template<> class LayerWriter<Zipper> {
+    Zipper m_zip;
 public:
 
-    Zipper(const std::string& zipfile_path):
-        m_fpath(zipfile_path),
-        m_zipfile(zipfile_path),
-        m_zipstream(m_zipfile),
-        m_pngstream(m_zipstream)
-    {
-        if(!m_zipfile.IsOk())
-            throw std::runtime_error(L("Cannot create zip file."));
-    }
+    inline LayerWriter(const std::string& zipfile_path): m_zip(zipfile_path) {}
 
-    void next_entry(const std::string& fname) {
-        m_zipstream.PutNextEntry(fname);
-    }
+    inline void next_entry(const std::string& fname) { m_zip.next_entry(fname); }
 
-    std::string get_name() {
-        return m_fpath.GetName().ToStdString();
-    }
+    inline std::string get_name() const { return m_zip.get_name(); }
 
-    template<class T> Zipper& operator<<(const T& arg) {
-        m_pngstream << arg; return *this;
+    template<class T> inline LayerWriter& operator<<(const T& arg) {
+        m_zip.stream() << arg; return *this;
     }
 
-    void close() {
-        m_zipstream.Close();
-        m_zipfile.Close();
-    }
+    inline void close() { m_zip.close(); }
 };
 
 void PrintController::slice_to_png()
 {
     using Pointf3 = Vec3d;
 
+    auto ctl = GUI::get_appctl();
     auto presetbundle = GUI::get_preset_bundle();
 
     assert(presetbundle);
 
+    // FIXME: this crashes in command line mode
     auto pt = presetbundle->printers.get_selected_preset().printer_technology();
     if(pt != ptSLA) {
-        report_issue(IssueType::ERR, L("Printer technology is not SLA!"),
+        ctl->report_issue(IssueType::ERR, L("Printer technology is not SLA!"),
                      L("Error"));
         return;
     }
@@ -348,13 +160,13 @@ void PrintController::slice_to_png()
     auto exd = query_png_export_data(conf);
     if(exd.zippath.empty()) return;
 
-    Print *print = print_;
+    Print *print = m_print;
 
     try {
         print->apply_config(conf);
         print->validate();
     } catch(std::exception& e) {
-        report_issue(IssueType::ERR, e.what(), "Error");
+        ctl->report_issue(IssueType::ERR, e.what(), "Error");
         return;
     }
 
@@ -400,13 +212,13 @@ void PrintController::slice_to_png()
            << L("Width needed: ") << px(punsc) << " mm\n"
            << L("Height needed: ") << py(punsc) << " mm\n";
 
-       if(!report_issue(IssueType::WARN_Q, ss.str(), L("Warning")))  {
+       if(!ctl->report_issue(IssueType::WARN_Q, ss.str(), L("Warning")))  {
             scale_back();
             return;
        }
     }
 
-    auto pri = create_progress_indicator(
+    auto pri = ctl->create_progress_indicator(
                 200, L("Slicing to zipped png files..."));
 
     pri->on_cancel([&print](){ print->cancel(); });
@@ -415,7 +227,7 @@ void PrintController::slice_to_png()
         pri->update(0, L("Slicing..."));
         slice(pri);
     } catch (std::exception& e) {
-        report_issue(IssueType::ERR, e.what(), L("Exception occurred"));
+        ctl->report_issue(IssueType::ERR, e.what(), L("Exception occurred"));
         scale_back();
         if(print->canceled()) print->restart();
         return;
@@ -428,22 +240,23 @@ void PrintController::slice_to_png()
     });
 
     try {
-        print_to<FilePrinterFormat::PNG, wxZipper>( *print, exd.zippath,
+        print_to<FilePrinterFormat::PNG, Zipper>( *print, exd.zippath,
                     exd.width_mm, exd.height_mm,
                     exd.width_px, exd.height_px,
                     exd.exp_time_s, exd.exp_time_first_s);
 
     } catch (std::exception& e) {
-        report_issue(IssueType::ERR, e.what(), L("Exception occurred"));
+        ctl->report_issue(IssueType::ERR, e.what(), L("Exception occurred"));
     }
 
     scale_back();
     if(print->canceled()) print->restart();
+    print->set_status_default();
 }
 
 const PrintConfig &PrintController::config() const
 {
-    return print_->config();
+    return m_print->config();
 }
 
 void ProgressIndicator::message_fmt(
@@ -477,15 +290,17 @@ void AppController::arrange_model()
 {
     using Coord = libnest2d::TCoord<libnest2d::PointImpl>;
 
-    if(arranging_.load()) return;
+    auto ctl = GUI::get_appctl();
+
+    if(m_arranging.load()) return;
 
     // to prevent UI reentrancies
-    arranging_.store(true);
+    m_arranging.store(true);
 
     unsigned count = 0;
-    for(auto obj : model_->objects) count += obj->instances.size();
+    for(auto obj : m_model->objects) count += obj->instances.size();
 
-    auto pind = global_progress_indicator();
+    auto pind = ctl->global_progress_indicator();
 
     float pmax = 1.0;
 
@@ -496,7 +311,7 @@ void AppController::arrange_model()
         pind->max(count);
 
         pind->on_cancel([this](){
-            arranging_.store(false);
+            m_arranging.store(false);
         });
     }
 
@@ -517,20 +332,20 @@ void AppController::arrange_model()
         // TODO: from Sasha from GUI
         hint.type = arr::BedShapeType::WHO_KNOWS;
 
-        arr::arrange(*model_,
+        arr::arrange(*m_model,
                       min_obj_distance,
                       bed,
                       hint,
                       false, // create many piles not just one pile
-                      [this, pind, count](unsigned rem) {
+                      [this, pind, &ctl, count](unsigned rem) {
             if(pind)
                 pind->update(count - rem, L("Arranging objects..."));
 
-            process_events();
-        }, [this] () { return !arranging_.load(); });
+            ctl->process_events();
+        }, [this] () { return !m_arranging.load(); });
     } catch(std::exception& e) {
         std::cerr << e.what() << std::endl;
-        report_issue(IssueType::ERR,
+        ctl->report_issue(IssueType::ERR,
                         L("Could not arrange model objects! "
                         "Some geometries may be invalid."),
                         L("Exception occurred"));
@@ -539,13 +354,13 @@ void AppController::arrange_model()
     // Restore previous max value
     if(pind) {
         pind->max(pmax);
-        pind->update(0, arranging_.load() ? L("Arranging done.") :
+        pind->update(0, m_arranging.load() ? L("Arranging done.") :
                                             L("Arranging canceled."));
 
         pind->on_cancel(/*remove cancel function*/);
     }
 
-    arranging_.store(false);
+    m_arranging.store(false);
 }
 
 }
diff --git a/src/slic3r/AppController.hpp b/src/slic3r/AppController.hpp
index 88d1f0eca..a34e5d035 100644
--- a/src/slic3r/AppController.hpp
+++ b/src/slic3r/AppController.hpp
@@ -20,6 +20,21 @@ class PrintConfig;
 class ProgressStatusBar;
 class DynamicPrintConfig;
 
+/// A Progress indicator object smart pointer
+using ProgresIndicatorPtr = std::shared_ptr<ProgressIndicator>;
+
+using FilePath = std::string;
+using FilePathList = std::vector<FilePath>;
+
+/// Common runtime issue types
+enum class IssueType {
+    INFO,
+    WARN,
+    WARN_Q,     // Warning with a question to continue
+    ERR,
+    FATAL
+};
+
 /**
  * @brief A boilerplate class for creating application logic. It should provide
  * features as issue reporting and progress indication, etc...
@@ -32,34 +47,12 @@ class DynamicPrintConfig;
  * UI toolkit dependencies. We can implement it with any UI framework or make it
  * a cli client.
  */
-class AppControllerBoilerplate {
+class AppControllerBase {
 public:
 
-    /// A Progress indicator object smart pointer
-    using ProgresIndicatorPtr = std::shared_ptr<ProgressIndicator>;
-
-private:
-    class PriData;   // Some structure to store progress indication data
+    using Ptr = std::shared_ptr<AppControllerBase>;
 
-    // Pimpl data for thread safe progress indication features
-    std::unique_ptr<PriData> pri_data_;
-
-public:
-
-    AppControllerBoilerplate();
-    ~AppControllerBoilerplate();
-
-    using Path = std::string;
-    using PathList = std::vector<Path>;
-
-    /// Common runtime issue types
-    enum class IssueType {
-        INFO,
-        WARN,
-        WARN_Q,     // Warning with a question to continue
-        ERR,
-        FATAL
-    };
+    inline virtual ~AppControllerBase() {}
 
     /**
      * @brief Query some paths from the user.
@@ -67,25 +60,30 @@ public:
      * It should display a file chooser dialog in case of a UI application.
      * @param title Title of a possible query dialog.
      * @param extensions Recognized file extensions.
-     * @return Returns a list of paths choosed by the user.
+     * @return Returns a list of paths chosen by the user.
      */
-    PathList query_destination_paths(
+    virtual FilePathList query_destination_paths(
             const std::string& title,
-            const std::string& extensions) const;
+            const std::string& extensions,
+            const std::string& functionid = "",
+            const std::string& hint = "") const = 0;
 
     /**
      * @brief Same as query_destination_paths but works for directories only.
      */
-    PathList query_destination_dirs(
-            const std::string& title) const;
+    virtual FilePathList query_destination_dirs(
+            const std::string& title,
+            const std::string& functionid = "",
+            const std::string& hint = "") const = 0;
 
     /**
      * @brief Same as query_destination_paths but returns only one path.
      */
-    Path query_destination_path(
+    virtual FilePath query_destination_path(
             const std::string& title,
             const std::string& extensions,
-            const std::string& hint = "") const;
+            const std::string& functionid = "",
+            const std::string& hint = "") const = 0;
 
     /**
      * @brief Report an issue to the user be it fatal or recoverable.
@@ -97,12 +95,9 @@ public:
      * @param brief A very brief description. Can be used for message dialog
      * title.
      */
-    bool report_issue(IssueType issuetype,
-                      const std::string& description,
-                      const std::string& brief);
-
-    bool report_issue(IssueType issuetype,
-                      const std::string& description);
+    virtual bool report_issue(IssueType issuetype,
+                              const std::string& description,
+                              const std::string& brief) = 0;
 
     /**
      * @brief Return the global progress indicator for the current controller.
@@ -110,9 +105,9 @@ public:
      *
      * Only one thread should use the global indicator at a time.
      */
-    ProgresIndicatorPtr global_progress_indicator();
+    virtual ProgresIndicatorPtr global_progress_indicator() = 0;
 
-    void global_progress_indicator(ProgresIndicatorPtr gpri);
+    virtual void global_progress_indicator(ProgresIndicatorPtr gpri) = 0;
 
     /**
      * @brief A predicate telling the caller whether it is the thread that
@@ -122,7 +117,7 @@ public:
      * @return Return true for the same caller thread that created this
      * object and false for every other.
      */
-    bool is_main_thread() const;
+    virtual bool is_main_thread() const = 0;
 
     /**
      * @brief The frontend supports asynch execution.
@@ -138,11 +133,9 @@ public:
      * @return true if a job or method can be executed asynchronously, false
      * otherwise.
      */
-    bool supports_asynch() const;
-
-    void process_events();
+    virtual bool supports_asynch() const = 0;
 
-protected:
+    virtual void process_events() = 0;
 
     /**
      * @brief Create a new progress indicator and return a smart pointer to it.
@@ -151,36 +144,169 @@ protected:
      * @param firstmsg The message for the first subtask to be displayed.
      * @return Smart pointer to the created object.
      */
-    ProgresIndicatorPtr create_progress_indicator(
+    virtual ProgresIndicatorPtr create_progress_indicator(
             unsigned statenum,
             const std::string& title,
-            const std::string& firstmsg) const;
+            const std::string& firstmsg = "") const = 0;
+};
+
+/**
+ * @brief Implementation of AppControllerBase for the GUI app
+ */
+class AppControllerGui: public AppControllerBase {
+private:
+    class PriData;   // Some structure to store progress indication data
+
+    // Pimpl data for thread safe progress indication features
+    std::unique_ptr<PriData> m_pri_data;
+
+public:
+
+    AppControllerGui();
+
+    virtual ~AppControllerGui();
+
+    virtual FilePathList query_destination_paths(
+            const std::string& title,
+            const std::string& extensions,
+            const std::string& functionid,
+            const std::string& hint) const override;
+
+    virtual FilePathList query_destination_dirs(
+            const std::string& /*title*/,
+            const std::string& /*functionid*/,
+            const std::string& /*hint*/) const override { return {}; }
+
+    virtual FilePath query_destination_path(
+            const std::string& title,
+            const std::string& extensions,
+            const std::string& functionid,
+            const std::string& hint) const override;
+
+    virtual bool report_issue(IssueType issuetype,
+                              const std::string& description,
+                              const std::string& brief = std::string()) override;
+
+    virtual ProgresIndicatorPtr global_progress_indicator() override;
+
+    virtual void global_progress_indicator(ProgresIndicatorPtr gpri) override;
+
+    virtual bool is_main_thread() const override;
+
+    virtual bool supports_asynch() const override;
 
-    ProgresIndicatorPtr create_progress_indicator(
+    virtual void process_events() override;
+
+    virtual ProgresIndicatorPtr create_progress_indicator(
             unsigned statenum,
-            const std::string& title) const;
+            const std::string& title,
+            const std::string& firstmsg) const override;
+
+protected:
 
     // This is a global progress indicator placeholder. In the Slic3r UI it can
     // contain the progress indicator on the statusbar.
-    ProgresIndicatorPtr global_progressind_;
+    ProgresIndicatorPtr m_global_progressind;
+};
+
+class AppControllerCli: public AppControllerBase {
+
+    class CliProgress : public ProgressIndicator {
+        std::string m_msg, m_title;
+    public:
+        virtual void message(const std::string& msg) override {
+            m_msg = msg;
+        }
+
+        virtual void title(const std::string& title) override {
+            m_title = title;
+        }
+    };
+
+public:
+
+    AppControllerCli() {
+        std::cout << "Cli AppController ready..." << std::endl;
+        m_global_progressind = std::make_shared<CliProgress>();
+    }
+
+    virtual ~AppControllerCli() {}
+
+    virtual FilePathList query_destination_paths(
+            const std::string& /*title*/,
+            const std::string& /*extensions*/,
+            const std::string& /*functionid*/,
+            const std::string& /*hint*/) const override { return {}; }
+
+    virtual FilePathList query_destination_dirs(
+            const std::string& /*title*/,
+            const std::string& /*functionid*/,
+            const std::string& /*hint*/) const override { return {}; }
+
+    virtual FilePath query_destination_path(
+            const std::string& /*title*/,
+            const std::string& /*extensions*/,
+            const std::string& /*functionid*/,
+            const std::string& /*hint*/) const override { return "out.zip"; }
+
+    virtual bool report_issue(IssueType /*issuetype*/,
+                              const std::string& description,
+                              const std::string& brief) override {
+        std::cerr << brief << ": " << description << std::endl;
+        return true;
+    }
+
+    virtual ProgresIndicatorPtr global_progress_indicator() override {
+        return m_global_progressind;
+    }
+
+    virtual void global_progress_indicator(ProgresIndicatorPtr) override {}
+
+    virtual bool is_main_thread() const override { return true; }
+
+    virtual bool supports_asynch() const override { return false; }
+
+    virtual void process_events() override {}
+
+    virtual ProgresIndicatorPtr create_progress_indicator(
+            unsigned /*statenum*/,
+            const std::string& /*title*/,
+            const std::string& /*firstmsg*/) const override {
+        return std::make_shared<CliProgress>();
+    }
+
+protected:
+
+    // This is a global progress indicator placeholder. In the Slic3r UI it can
+    // contain the progress indicator on the statusbar.
+    ProgresIndicatorPtr m_global_progressind;
+};
+
+class Zipper {
+    struct Impl;
+    std::unique_ptr<Impl> m_impl;
+public:
+
+    Zipper(const std::string& zipfilepath);
+    ~Zipper();
+
+    void next_entry(const std::string& fname);
+
+    std::string get_name() const;
+
+    std::ostream& stream();
+
+    void close();
 };
 
 /**
  * @brief Implementation of the printing logic.
  */
-class PrintController: public AppControllerBoilerplate {
-    Print *print_ = nullptr;
-    std::function<void()> rempools_;
+class PrintController {
+    Print *m_print = nullptr;
+    std::function<void()> m_rempools;
 protected:
 
-    void make_skirt() {}
-    void make_brim() {}
-    void make_wipe_tower() {}
-
-    void make_perimeters(PrintObject *pobj) {}
-    void infill(PrintObject *pobj) {}
-    void gen_support_material(PrintObject *pobj) {}
-
     // Data structure with the png export input data
     struct PngExportData {
         std::string zippath;                        // output zip file
@@ -198,20 +324,14 @@ protected:
     PngExportData query_png_export_data(const DynamicPrintConfig&);
 
     // The previous export data, to pre-populate the dialog
-    PngExportData prev_expdata_;
-
-    /**
-     * @brief Slice one pront object.
-     * @param pobj The print object.
-     */
-    void slice(PrintObject *pobj);
+    PngExportData m_prev_expdata;
 
     void slice(ProgresIndicatorPtr pri);
 
 public:
 
     // Must be public for perl to use it
-    explicit inline PrintController(Print *print): print_(print) {}
+    explicit inline PrintController(Print *print): m_print(print) {}
 
     PrintController(const PrintController&) = delete;
     PrintController(PrintController&&) = delete;
@@ -238,10 +358,10 @@ public:
 /**
  * @brief Top level controller.
  */
-class AppController: public AppControllerBoilerplate {
-    Model *model_ = nullptr;
+class AppController {
+    Model *m_model = nullptr;
     PrintController::Ptr printctl;
-    std::atomic<bool> arranging_;
+    std::atomic<bool> m_arranging;
 public:
 
     /**
@@ -258,7 +378,7 @@ public:
      * @param model A raw pointer to the model object. This can be used from
      * perl.
      */
-    void set_model(Model *model) { model_ = model; }
+    void set_model(Model *model) { m_model = model; }
 
     /**
      * @brief Set the print object from perl.
diff --git a/src/slic3r/AppControllerWx.cpp b/src/slic3r/AppControllerWx.cpp
index 4d67d5f66..25cd739f3 100644
--- a/src/slic3r/AppControllerWx.cpp
+++ b/src/slic3r/AppControllerWx.cpp
@@ -1,5 +1,9 @@
 #include "AppController.hpp"
 
+#include <wx/stdstream.h>
+#include <wx/wfstream.h>
+#include <wx/zipstrm.h>
+
 #include <thread>
 #include <future>
 
@@ -21,40 +25,43 @@
 
 namespace Slic3r {
 
-bool AppControllerBoilerplate::supports_asynch() const
+bool AppControllerGui::supports_asynch() const
 {
     return true;
 }
 
-void AppControllerBoilerplate::process_events()
+void AppControllerGui::process_events()
 {
     wxYieldIfNeeded();
 }
 
-AppControllerBoilerplate::PathList
-AppControllerBoilerplate::query_destination_paths(
+FilePathList AppControllerGui::query_destination_paths(
         const std::string &title,
-        const std::string &extensions) const
+        const std::string &extensions,
+        const std::string &/*functionid*/,
+        const std::string& hint) const
 {
 
     wxFileDialog dlg(wxTheApp->GetTopWindow(), _(title) );
     dlg.SetWildcard(extensions);
 
-    dlg.ShowModal();
+    dlg.SetFilename(hint);
 
-    wxArrayString paths;
-    dlg.GetPaths(paths);
+    FilePathList ret;
 
-    PathList ret(paths.size(), "");
-    for(auto& p : paths) ret.push_back(p.ToStdString());
+    if(dlg.ShowModal() == wxID_OK) {
+        wxArrayString paths;
+        dlg.GetPaths(paths);
+        for(auto& p : paths) ret.push_back(p.ToStdString());
+    }
 
     return ret;
 }
 
-AppControllerBoilerplate::Path
-AppControllerBoilerplate::query_destination_path(
+FilePath AppControllerGui::query_destination_path(
         const std::string &title,
         const std::string &extensions,
+        const std::string &/*functionid*/,
         const std::string& hint) const
 {
     wxFileDialog dlg(wxTheApp->GetTopWindow(), _(title) );
@@ -62,16 +69,16 @@ AppControllerBoilerplate::query_destination_path(
 
     dlg.SetFilename(hint);
 
-    Path ret;
+    FilePath ret;
 
     if(dlg.ShowModal() == wxID_OK) {
-        ret = Path(dlg.GetPath());
+        ret = FilePath(dlg.GetPath());
     }
 
     return ret;
 }
 
-bool AppControllerBoilerplate::report_issue(IssueType issuetype,
+bool AppControllerGui::report_issue(IssueType issuetype,
                                  const std::string &description,
                                  const std::string &brief)
 {
@@ -89,14 +96,52 @@ bool AppControllerBoilerplate::report_issue(IssueType issuetype,
     return ret != wxCANCEL;
 }
 
-bool AppControllerBoilerplate::report_issue(
-        AppControllerBoilerplate::IssueType issuetype,
-        const std::string &description)
+wxDEFINE_EVENT(PROGRESS_STATUS_UPDATE_EVENT, wxCommandEvent);
+
+struct Zipper::Impl {
+    wxFileName fpath;
+    wxFFileOutputStream zipfile;
+    wxZipOutputStream zipstream;
+    wxStdOutputStream pngstream;
+
+    Impl(const std::string& zipfile_path):
+        fpath(zipfile_path),
+        zipfile(zipfile_path),
+        zipstream(zipfile),
+        pngstream(zipstream)
+    {
+        if(!zipfile.IsOk())
+            throw std::runtime_error(L("Cannot create zip file."));
+    }
+};
+
+Zipper::Zipper(const std::string &zipfilepath)
 {
-    return report_issue(issuetype, description, std::string());
+    m_impl.reset(new Impl(zipfilepath));
 }
 
-wxDEFINE_EVENT(PROGRESS_STATUS_UPDATE_EVENT, wxCommandEvent);
+Zipper::~Zipper() {}
+
+void Zipper::next_entry(const std::string &fname)
+{
+    m_impl->zipstream.PutNextEntry(fname);
+}
+
+std::string Zipper::get_name() const
+{
+    return m_impl->fpath.GetName().ToStdString();
+}
+
+std::ostream &Zipper::stream()
+{
+    return m_impl->pngstream;
+}
+
+void Zipper::close()
+{
+    m_impl->zipstream.Close();
+    m_impl->zipfile.Close();
+}
 
 namespace  {
 
@@ -107,26 +152,26 @@ namespace  {
 class GuiProgressIndicator:
         public ProgressIndicator, public wxEvtHandler {
 
-    wxProgressDialog gauge_;
+    wxProgressDialog m_gauge;
     using Base = ProgressIndicator;
-    wxString message_;
-    int range_; wxString title_;
-    bool is_asynch_ = false;
+    wxString m_message;
+    int m_range; wxString m_title;
+    bool m_is_asynch = false;
 
-    const int id_ = wxWindow::NewControlId();
+    const int m_id = wxWindow::NewControlId();
 
     // status update handler
     void _state( wxCommandEvent& evt) {
         unsigned st = evt.GetInt();
-        message_ = evt.GetString();
+        m_message = evt.GetString();
         _state(st);
     }
 
     // Status update implementation
     void _state( unsigned st) {
-        if(!gauge_.IsShown()) gauge_.ShowModal();
+        if(!m_gauge.IsShown()) m_gauge.ShowModal();
         Base::state(st);
-        if(!gauge_.Update(static_cast<int>(st), message_)) {
+        if(!m_gauge.Update(static_cast<int>(st), m_message)) {
             cancel();
         }
     }
@@ -134,25 +179,25 @@ class GuiProgressIndicator:
 public:
 
     /// Setting whether it will be used from the UI thread or some worker thread
-    inline void asynch(bool is) { is_asynch_ = is; }
+    inline void asynch(bool is) { m_is_asynch = is; }
 
     /// Get the mode of parallel operation.
-    inline bool asynch() const { return is_asynch_; }
+    inline bool asynch() const { return m_is_asynch; }
 
     inline GuiProgressIndicator(int range, const wxString& title,
                                 const wxString& firstmsg) :
-        gauge_(title, firstmsg, range, wxTheApp->GetTopWindow(),
+        m_gauge(title, firstmsg, range, wxTheApp->GetTopWindow(),
                wxPD_APP_MODAL | wxPD_AUTO_HIDE | wxPD_CAN_ABORT),
 
-        message_(firstmsg),
-        range_(range), title_(title)
+        m_message(firstmsg),
+        m_range(range), m_title(title)
     {
         Base::max(static_cast<float>(range));
         Base::states(static_cast<unsigned>(range));
 
         Bind(PROGRESS_STATUS_UPDATE_EVENT,
              &GuiProgressIndicator::_state,
-             this, id_);
+             this, m_id);
     }
 
     virtual void state(float val) override {
@@ -161,33 +206,32 @@ public:
 
     void state(unsigned st) {
         // send status update event
-        if(is_asynch_) {
-            auto evt = new wxCommandEvent(PROGRESS_STATUS_UPDATE_EVENT, id_);
+        if(m_is_asynch) {
+            auto evt = new wxCommandEvent(PROGRESS_STATUS_UPDATE_EVENT, m_id);
             evt->SetInt(st);
-            evt->SetString(message_);
+            evt->SetString(m_message);
             wxQueueEvent(this, evt);
         } else _state(st);
     }
 
     virtual void message(const std::string & msg) override {
-        message_ = _(msg);
+        m_message = _(msg);
     }
 
     virtual void messageFmt(const std::string& fmt, ...) {
         va_list arglist;
         va_start(arglist, fmt);
-        message_ = wxString::Format(_(fmt), arglist);
+        m_message = wxString::Format(_(fmt), arglist);
         va_end(arglist);
     }
 
     virtual void title(const std::string & title) override {
-        title_ = _(title);
+        m_title = _(title);
     }
 };
 }
 
-AppControllerBoilerplate::ProgresIndicatorPtr
-AppControllerBoilerplate::create_progress_indicator(
+ProgresIndicatorPtr AppControllerGui::create_progress_indicator(
         unsigned statenum,
         const std::string& title,
         const std::string& firstmsg) const
@@ -202,30 +246,23 @@ AppControllerBoilerplate::create_progress_indicator(
     return pri;
 }
 
-AppControllerBoilerplate::ProgresIndicatorPtr
-AppControllerBoilerplate::create_progress_indicator(
-        unsigned statenum, const std::string &title) const
-{
-    return create_progress_indicator(statenum, title, std::string());
-}
-
 namespace {
 
 class Wrapper: public ProgressIndicator, public wxEvtHandler {
-    ProgressStatusBar *sbar_;
+    ProgressStatusBar *m_sbar;
     using Base = ProgressIndicator;
-    wxString message_;
-    AppControllerBoilerplate& ctl_;
+    wxString m_message;
+    AppControllerBase& m_ctl;
 
     void showProgress(bool show = true) {
-        sbar_->show_progress(show);
+        m_sbar->show_progress(show);
     }
 
     void _state(unsigned st) {
         if( st <= ProgressIndicator::max() ) {
             Base::state(st);
-            sbar_->set_status_text(message_);
-            sbar_->set_progress(st);
+            m_sbar->set_status_text(m_message);
+            m_sbar->set_progress(st);
         }
     }
 
@@ -239,11 +276,11 @@ class Wrapper: public ProgressIndicator, public wxEvtHandler {
 public:
 
     inline Wrapper(ProgressStatusBar *sbar,
-                   AppControllerBoilerplate& ctl):
-        sbar_(sbar), ctl_(ctl)
+                   AppControllerBase& ctl):
+        m_sbar(sbar), m_ctl(ctl)
     {
-        Base::max(static_cast<float>(sbar_->get_range()));
-        Base::states(static_cast<unsigned>(sbar_->get_range()));
+        Base::max(static_cast<float>(m_sbar->get_range()));
+        Base::states(static_cast<unsigned>(m_sbar->get_range()));
 
         Bind(PROGRESS_STATUS_UPDATE_EVENT,
              &Wrapper::_state,
@@ -256,13 +293,13 @@ public:
 
     virtual void max(float val) override {
         if(val > 1.0) {
-            sbar_->set_range(static_cast<int>(val));
+            m_sbar->set_range(static_cast<int>(val));
             ProgressIndicator::max(val);
         }
     }
 
     void state(unsigned st) {
-        if(!ctl_.is_main_thread()) {
+        if(!m_ctl.is_main_thread()) {
             auto evt = new wxCommandEvent(PROGRESS_STATUS_UPDATE_EVENT, id_);
             evt->SetInt(st);
             wxQueueEvent(this, evt);
@@ -272,20 +309,20 @@ public:
     }
 
     virtual void message(const std::string & msg) override {
-        message_ = _(msg);
+        m_message = _(msg);
     }
 
     virtual void message_fmt(const std::string& fmt, ...) override {
         va_list arglist;
         va_start(arglist, fmt);
-        message_ = wxString::Format(_(fmt), arglist);
+        m_message = wxString::Format(_(fmt), arglist);
         va_end(arglist);
     }
 
     virtual void title(const std::string & /*title*/) override {}
 
     virtual void on_cancel(CancelFn fn) override {
-        sbar_->set_cancel_callback(fn);
+        m_sbar->set_cancel_callback(fn);
         Base::on_cancel(fn);
     }
 
@@ -295,7 +332,8 @@ public:
 void AppController::set_global_progress_indicator(ProgressStatusBar *prsb)
 {
     if(prsb) {
-        global_progress_indicator(std::make_shared<Wrapper>(prsb, *this));
+        auto ctl = GUI::get_appctl();
+        ctl->global_progress_indicator(std::make_shared<Wrapper>(prsb, *ctl));
     }
 }
 
diff --git a/src/slic3r/GUI/3DScene.cpp b/src/slic3r/GUI/3DScene.cpp
index e6f038042..5b830b30d 100644
--- a/src/slic3r/GUI/3DScene.cpp
+++ b/src/slic3r/GUI/3DScene.cpp
@@ -196,7 +196,11 @@ const float GLVolume::SELECTED_OUTSIDE_COLOR[4] = { 0.19f, 0.58f, 1.0f, 1.0f };
 
 GLVolume::GLVolume(float r, float g, float b, float a)
     : m_offset(Vec3d::Zero())
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    , m_rotation(Vec3d::Zero())
+#else
     , m_rotation(0.0)
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
     , m_scaling_factor(1.0)
     , m_world_matrix(Transform3f::Identity())
     , m_world_matrix_dirty(true)
@@ -255,7 +259,24 @@ void GLVolume::set_render_color()
         set_render_color(color, 4);
 }
 
-double GLVolume::get_rotation()
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+const Vec3d& GLVolume::get_rotation() const
+{
+    return m_rotation;
+}
+
+void GLVolume::set_rotation(const Vec3d& rotation)
+{
+    if (m_rotation != rotation)
+    {
+        m_rotation = rotation;
+        m_world_matrix_dirty = true;
+        m_transformed_bounding_box_dirty = true;
+        m_transformed_convex_hull_bounding_box_dirty = true;
+    }
+}
+#else
+double GLVolume::get_rotation() const
 {
     return m_rotation;
 }
@@ -270,6 +291,7 @@ void GLVolume::set_rotation(double rotation)
         m_transformed_convex_hull_bounding_box_dirty = true;
     }
 }
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 
 const Vec3d& GLVolume::get_offset() const
 {
@@ -327,7 +349,13 @@ const Transform3f& GLVolume::world_matrix() const
     {
         m_world_matrix = Transform3f::Identity();
         m_world_matrix.translate(m_offset.cast<float>());
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+        m_world_matrix.rotate(Eigen::AngleAxisf((float)m_rotation(2), Vec3f::UnitZ()));
+        m_world_matrix.rotate(Eigen::AngleAxisf((float)m_rotation(1), Vec3f::UnitY()));
+        m_world_matrix.rotate(Eigen::AngleAxisf((float)m_rotation(0), Vec3f::UnitX()));
+#else
         m_world_matrix.rotate(Eigen::AngleAxisf((float)m_rotation, Vec3f::UnitZ()));
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
         m_world_matrix.scale((float)m_scaling_factor);
         m_world_matrix_dirty = false;
     }
@@ -403,7 +431,13 @@ void GLVolume::render() const
     ::glCullFace(GL_BACK);
     ::glPushMatrix();
     ::glTranslated(m_offset(0), m_offset(1), m_offset(2));
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    ::glRotated(m_rotation(2) * 180.0 / (double)PI, 0.0, 0.0, 1.0);
+    ::glRotated(m_rotation(1) * 180.0 / (double)PI, 0.0, 1.0, 0.0);
+    ::glRotated(m_rotation(0) * 180.0 / (double)PI, 1.0, 0.0, 0.0);
+#else
     ::glRotated(m_rotation * 180.0 / (double)PI, 0.0, 0.0, 1.0);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
     ::glScaled(m_scaling_factor, m_scaling_factor, m_scaling_factor);
     if (this->indexed_vertex_array.indexed())
         this->indexed_vertex_array.render(this->tverts_range, this->qverts_range);
@@ -529,7 +563,13 @@ void GLVolume::render_VBOs(int color_id, int detection_id, int worldmatrix_id) c
 
     ::glPushMatrix();
     ::glTranslated(m_offset(0), m_offset(1), m_offset(2));
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    ::glRotated(m_rotation(2) * 180.0 / (double)PI, 0.0, 0.0, 1.0);
+    ::glRotated(m_rotation(1) * 180.0 / (double)PI, 0.0, 1.0, 0.0);
+    ::glRotated(m_rotation(0) * 180.0 / (double)PI, 1.0, 0.0, 0.0);
+#else
     ::glRotated(m_rotation * 180.0 / (double)PI, 0.0, 0.0, 1.0);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
     ::glScaled(m_scaling_factor, m_scaling_factor, m_scaling_factor);
 
     if (n_triangles > 0)
@@ -574,7 +614,13 @@ void GLVolume::render_legacy() const
 
     ::glPushMatrix();
     ::glTranslated(m_offset(0), m_offset(1), m_offset(2));
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    ::glRotated(m_rotation(2) * 180.0 / (double)PI, 0.0, 0.0, 1.0);
+    ::glRotated(m_rotation(1) * 180.0 / (double)PI, 0.0, 1.0, 0.0);
+    ::glRotated(m_rotation(0) * 180.0 / (double)PI, 1.0, 0.0, 0.0);
+#else
     ::glRotated(m_rotation * 180.0 / (double)PI, 0.0, 0.0, 1.0);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
     ::glScaled(m_scaling_factor, m_scaling_factor, m_scaling_factor);
 
     if (n_triangles > 0)
@@ -698,7 +744,11 @@ std::vector<int> GLVolumeCollection::load_object(
 #else
             v.set_offset(Vec3d(instance->offset(0), instance->offset(1), 0.0));
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+            v.set_rotation(instance->get_rotation());
+#else
             v.set_rotation(instance->rotation);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
             v.set_scaling_factor(instance->scaling_factor);
         }
     }
@@ -2067,12 +2117,30 @@ void _3DScene::register_on_gizmo_scale_uniformly_callback(wxGLCanvas* canvas, vo
 
 void _3DScene::register_on_gizmo_rotate_callback(wxGLCanvas* canvas, void* callback)
 {
+#if !ENABLE_MODELINSTANCE_3D_ROTATION
     s_canvas_mgr.register_on_gizmo_rotate_callback(canvas, callback);
+#endif // !ENABLE_MODELINSTANCE_3D_ROTATION
+}
+
+void _3DScene::register_on_gizmo_rotate_3D_callback(wxGLCanvas* canvas, void* callback)
+{
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    s_canvas_mgr.register_on_gizmo_rotate_3D_callback(canvas, callback);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 }
 
 void _3DScene::register_on_gizmo_flatten_callback(wxGLCanvas* canvas, void* callback)
 {
+#if !ENABLE_MODELINSTANCE_3D_ROTATION
     s_canvas_mgr.register_on_gizmo_flatten_callback(canvas, callback);
+#endif // !ENABLE_MODELINSTANCE_3D_ROTATION
+}
+
+void _3DScene::register_on_gizmo_flatten_3D_callback(wxGLCanvas* canvas, void* callback)
+{
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    s_canvas_mgr.register_on_gizmo_flatten_3D_callback(canvas, callback);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 }
 
 void _3DScene::register_on_update_geometry_info_callback(wxGLCanvas* canvas, void* callback)
diff --git a/src/slic3r/GUI/3DScene.hpp b/src/slic3r/GUI/3DScene.hpp
index f2d1c0786..8fc1661fc 100644
--- a/src/slic3r/GUI/3DScene.hpp
+++ b/src/slic3r/GUI/3DScene.hpp
@@ -256,8 +256,13 @@ public:
 private:
     // Offset of the volume to be rendered.
     Vec3d                 m_offset;
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    // Rotation around three axes of the volume to be rendered.
+    Vec3d                 m_rotation;
+#else
     // Rotation around Z axis of the volume to be rendered.
     double                m_rotation;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
     // Scale factor of the volume to be rendered.
     double                m_scaling_factor;
     // World matrix of the volume to be rendered.
@@ -327,8 +332,13 @@ public:
     // Sets render color in dependence of current state
     void set_render_color();
 
-    double get_rotation();
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    const Vec3d& get_rotation() const;
+    void set_rotation(const Vec3d& rotation);
+#else
+    double get_rotation() const;
     void set_rotation(double rotation);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 
     const Vec3d& get_offset() const;
     void set_offset(const Vec3d& offset);
@@ -558,7 +568,9 @@ public:
     static void register_on_enable_action_buttons_callback(wxGLCanvas* canvas, void* callback);
     static void register_on_gizmo_scale_uniformly_callback(wxGLCanvas* canvas, void* callback);
     static void register_on_gizmo_rotate_callback(wxGLCanvas* canvas, void* callback);
+    static void register_on_gizmo_rotate_3D_callback(wxGLCanvas* canvas, void* callback);
     static void register_on_gizmo_flatten_callback(wxGLCanvas* canvas, void* callback);
+    static void register_on_gizmo_flatten_3D_callback(wxGLCanvas* canvas, void* callback);
     static void register_on_update_geometry_info_callback(wxGLCanvas* canvas, void* callback);
 
     static void register_action_add_callback(wxGLCanvas* canvas, void* callback);
diff --git a/src/slic3r/GUI/GLCanvas3D.cpp b/src/slic3r/GUI/GLCanvas3D.cpp
index cb3250916..658e1731a 100644
--- a/src/slic3r/GUI/GLCanvas3D.cpp
+++ b/src/slic3r/GUI/GLCanvas3D.cpp
@@ -1095,6 +1095,9 @@ GLCanvas3D::Mouse::Drag::Drag()
 GLCanvas3D::Mouse::Mouse()
     : dragging(false)
     , position(DBL_MAX, DBL_MAX)
+#if ENABLE_GIZMOS_RESET
+    , ignore_up_event(false)
+#endif // ENABLE_GIZMOS_RESET
 {
 }
 
@@ -1181,9 +1184,11 @@ bool GLCanvas3D::Gizmos::init(GLCanvas3D& parent)
         return false;
     }
 
+#if !ENABLE_MODELINSTANCE_3D_ROTATION
     // temporary disable x and y grabbers
     gizmo->disable_grabber(0);
     gizmo->disable_grabber(1);
+#endif // !ENABLE_MODELINSTANCE_3D_ROTATION
 
     m_gizmos.insert(GizmosMap::value_type(Rotate, gizmo));
 
@@ -1349,6 +1354,18 @@ void GLCanvas3D::Gizmos::update(const Linef3& mouse_ray)
         curr->update(mouse_ray);
 }
 
+#if ENABLE_GIZMOS_RESET
+void GLCanvas3D::Gizmos::process_double_click()
+{
+    if (!m_enabled)
+        return;
+
+    GLGizmoBase* curr = _get_current();
+    if (curr != nullptr)
+        curr->process_double_click();
+}
+#endif // ENABLE_GIZMOS_RESET
+
 GLCanvas3D::Gizmos::EType GLCanvas3D::Gizmos::get_current_type() const
 {
     return m_current;
@@ -1421,6 +1438,35 @@ void GLCanvas3D::Gizmos::set_scale(float scale)
         reinterpret_cast<GLGizmoScale3D*>(it->second)->set_scale(scale);
 }
 
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+Vec3d GLCanvas3D::Gizmos::get_rotation() const
+{
+    if (!m_enabled)
+        return Vec3d::Zero();
+
+    GizmosMap::const_iterator it = m_gizmos.find(Rotate);
+    return (it != m_gizmos.end()) ? reinterpret_cast<GLGizmoRotate3D*>(it->second)->get_rotation() : Vec3d::Zero();
+}
+
+void GLCanvas3D::Gizmos::set_rotation(const Vec3d& rotation)
+{
+    if (!m_enabled)
+        return;
+
+    GizmosMap::const_iterator it = m_gizmos.find(Rotate);
+    if (it != m_gizmos.end())
+        reinterpret_cast<GLGizmoRotate3D*>(it->second)->set_rotation(rotation);
+}
+
+Vec3d GLCanvas3D::Gizmos::get_flattening_rotation() const
+{
+    if (!m_enabled)
+        return Vec3d::Zero();
+
+    GizmosMap::const_iterator it = m_gizmos.find(Flatten);
+    return (it != m_gizmos.end()) ? reinterpret_cast<GLGizmoFlatten*>(it->second)->get_flattening_rotation() : Vec3d::Zero();
+}
+#else
 float GLCanvas3D::Gizmos::get_angle_z() const
 {
     if (!m_enabled)
@@ -1448,6 +1494,7 @@ Vec3d GLCanvas3D::Gizmos::get_flattening_normal() const
     GizmosMap::const_iterator it = m_gizmos.find(Flatten);
     return (it != m_gizmos.end()) ? reinterpret_cast<GLGizmoFlatten*>(it->second)->get_flattening_normal() : Vec3d::Zero();
 }
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 
 void GLCanvas3D::Gizmos::set_flattening_data(const ModelObject* model_object)
 {
@@ -2385,7 +2432,11 @@ void GLCanvas3D::update_gizmos_data()
                 m_gizmos.set_position(Vec3d(model_instance->offset(0), model_instance->offset(1), 0.0));
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
                 m_gizmos.set_scale(model_instance->scaling_factor);
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+                m_gizmos.set_rotation(model_instance->get_rotation());
+#else
                 m_gizmos.set_angle_z(model_instance->rotation);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
                 m_gizmos.set_flattening_data(model_object);
             }
         }
@@ -2394,7 +2445,11 @@ void GLCanvas3D::update_gizmos_data()
     {
         m_gizmos.set_position(Vec3d::Zero());
         m_gizmos.set_scale(1.0f);
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+        m_gizmos.set_rotation(Vec3d::Zero());
+#else
         m_gizmos.set_angle_z(0.0f);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
         m_gizmos.set_flattening_data(nullptr);
     }
 }
@@ -2757,6 +2812,19 @@ void GLCanvas3D::register_on_gizmo_scale_uniformly_callback(void* callback)
         m_on_gizmo_scale_uniformly_callback.register_callback(callback);
 }
 
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+void GLCanvas3D::register_on_gizmo_rotate_3D_callback(void* callback)
+{
+    if (callback != nullptr)
+        m_on_gizmo_rotate_3D_callback.register_callback(callback);
+}
+
+void GLCanvas3D::register_on_gizmo_flatten_3D_callback(void* callback)
+{
+    if (callback != nullptr)
+        m_on_gizmo_flatten_3D_callback.register_callback(callback);
+}
+#else
 void GLCanvas3D::register_on_gizmo_rotate_callback(void* callback)
 {
     if (callback != nullptr)
@@ -2768,6 +2836,7 @@ void GLCanvas3D::register_on_gizmo_flatten_callback(void* callback)
     if (callback != nullptr)
         m_on_gizmo_flatten_callback.register_callback(callback);
 }
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 
 void GLCanvas3D::register_on_update_geometry_info_callback(void* callback)
 {
@@ -3043,6 +3112,41 @@ void GLCanvas3D::on_mouse(wxMouseEvent& evt)
         m_toolbar_action_running = true;
         m_toolbar.do_action((unsigned int)toolbar_contains_mouse);
     }
+#if ENABLE_GIZMOS_RESET
+    else if (evt.LeftDClick() && m_gizmos.grabber_contains_mouse())
+    {
+#if ENABLE_GIZMOS_RESET
+        m_mouse.ignore_up_event = true;
+#endif // ENABLE_GIZMOS_RESET
+        m_gizmos.process_double_click();
+        switch (m_gizmos.get_current_type())
+        {
+        case Gizmos::Scale:
+        {
+            m_on_gizmo_scale_uniformly_callback.call((double)m_gizmos.get_scale());
+            update_scale_values();
+            m_dirty = true;
+            break;
+        }
+        case Gizmos::Rotate:
+        {
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+            const Vec3d& rotation = m_gizmos.get_rotation();
+            m_on_gizmo_rotate_3D_callback.call(rotation(0), rotation(1), rotation(2));
+#else
+            m_on_gizmo_rotate_callback.call((double)m_gizmos.get_angle_z());
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
+            update_rotation_values();
+            m_dirty = true;
+            break;
+        }
+        default:
+        {
+            break;
+        }
+        }
+    }
+#endif // ENABLE_GIZMOS_RESET
     else if (evt.LeftDown() || evt.RightDown())
     {
         // If user pressed left or right button we first check whether this happened
@@ -3083,6 +3187,11 @@ void GLCanvas3D::on_mouse(wxMouseEvent& evt)
             m_mouse.drag.gizmo_volume_idx = _get_first_selected_volume_id(selected_object_idx);
 
             if (m_gizmos.get_current_type() == Gizmos::Flatten) {
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+                // Rotate the object so the normal points downward:
+                const Vec3d& rotation = m_gizmos.get_flattening_rotation();
+                m_on_gizmo_flatten_3D_callback.call(rotation(0), rotation(1), rotation(2));
+#else
                 // Rotate the object so the normal points downward:
                 Vec3d normal = m_gizmos.get_flattening_normal();
                 if (normal(0) != 0.0 || normal(1) != 0.0 || normal(2) != 0.0) {
@@ -3090,6 +3199,7 @@ void GLCanvas3D::on_mouse(wxMouseEvent& evt)
                     float angle = acos(clamp(-1.0, 1.0, -normal(2)));
                     m_on_gizmo_flatten_callback.call(angle, (float)axis(0), (float)axis(1), (float)axis(2));
                 }
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
             }
 
             m_dirty = true;
@@ -3272,6 +3382,15 @@ void GLCanvas3D::on_mouse(wxMouseEvent& evt)
         }
         case Gizmos::Rotate:
         {
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+            // Apply new temporary rotation
+            Vec3d rotation = m_gizmos.get_rotation();
+            for (GLVolume* v : volumes)
+            {
+                v->set_rotation(rotation);
+            }
+            update_rotation_value(rotation);
+#else
             // Apply new temporary angle_z
             float angle_z = m_gizmos.get_angle_z();
             for (GLVolume* v : volumes)
@@ -3279,6 +3398,7 @@ void GLCanvas3D::on_mouse(wxMouseEvent& evt)
                 v->set_rotation((double)angle_z);
             }
             update_rotation_value((double)angle_z, Z);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
             break;
         }
         default:
@@ -3377,12 +3497,20 @@ void GLCanvas3D::on_mouse(wxMouseEvent& evt)
         else if (evt.LeftUp() && !m_mouse.dragging && (m_hover_volume_id == -1) && !gizmos_overlay_contains_mouse && !m_gizmos.is_dragging() && !is_layers_editing_enabled())
         {
             // deselect and propagate event through callback
+#if ENABLE_GIZMOS_RESET
+            if (!m_mouse.ignore_up_event && m_picking_enabled && !m_toolbar_action_running)
+#else
             if (m_picking_enabled && !m_toolbar_action_running)
+#endif // ENABLE_GIZMOS_RESET
             {
                 deselect_volumes();
                 _on_select(-1, -1);
                 update_gizmos_data();
             }
+#if ENABLE_GIZMOS_RESET
+            else if (m_mouse.ignore_up_event)
+                m_mouse.ignore_up_event = false;
+#endif // ENABLE_GIZMOS_RESET
         }
         else if (evt.LeftUp() && m_gizmos.is_dragging())
         {
@@ -3416,14 +3544,19 @@ void GLCanvas3D::on_mouse(wxMouseEvent& evt)
             }
             case Gizmos::Rotate:
             {
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+                const Vec3d& rotation = m_gizmos.get_rotation();
+                m_on_gizmo_rotate_3D_callback.call(rotation(0), rotation(1), rotation(2));
+#else
                 m_on_gizmo_rotate_callback.call((double)m_gizmos.get_angle_z());
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
                 break;
             }
             default:
                 break;
             }
             m_gizmos.stop_dragging();
-            Slic3r::GUI::update_settings_value();
+            update_settings_value();
         }
 
         m_mouse.drag.move_volume_idx = -1;
@@ -3863,8 +3996,13 @@ void GLCanvas3D::_deregister_callbacks()
     m_on_wipe_tower_moved_callback.deregister_callback();
     m_on_enable_action_buttons_callback.deregister_callback();
     m_on_gizmo_scale_uniformly_callback.deregister_callback();
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    m_on_gizmo_rotate_3D_callback.deregister_callback();
+    m_on_gizmo_flatten_3D_callback.deregister_callback();
+#else
     m_on_gizmo_rotate_callback.deregister_callback();
     m_on_gizmo_flatten_callback.deregister_callback();
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
     m_on_update_geometry_info_callback.deregister_callback();
 
     m_action_add_callback.deregister_callback();
diff --git a/src/slic3r/GUI/GLCanvas3D.hpp b/src/slic3r/GUI/GLCanvas3D.hpp
index 528f73fc1..712ffbefc 100644
--- a/src/slic3r/GUI/GLCanvas3D.hpp
+++ b/src/slic3r/GUI/GLCanvas3D.hpp
@@ -315,6 +315,9 @@ class GLCanvas3D
         bool dragging;
         Vec2d position;
         Drag drag;
+#if ENABLE_GIZMOS_RESET
+        bool ignore_up_event;
+#endif // ENABLE_GIZMOS_RESET
 
         Mouse();
 
@@ -366,6 +369,9 @@ class GLCanvas3D
         bool overlay_contains_mouse(const GLCanvas3D& canvas, const Vec2d& mouse_pos) const;
         bool grabber_contains_mouse() const;
         void update(const Linef3& mouse_ray);
+#if ENABLE_GIZMOS_RESET
+        void process_double_click();
+#endif // ENABLE_GIZMOS_RESET
 
         EType get_current_type() const;
 
@@ -381,11 +387,20 @@ class GLCanvas3D
         float get_scale() const;
         void set_scale(float scale);
 
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+        Vec3d get_rotation() const;
+        void set_rotation(const Vec3d& rotation);
+#else
         float get_angle_z() const;
         void set_angle_z(float angle_z);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 
-        void set_flattening_data(const ModelObject* model_object);
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+        Vec3d get_flattening_rotation() const;
+#else
         Vec3d get_flattening_normal() const;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
+        void set_flattening_data(const ModelObject* model_object);
 
         void render_current_gizmo(const BoundingBoxf3& box) const;
 
@@ -501,8 +516,13 @@ class GLCanvas3D
     PerlCallback m_on_wipe_tower_moved_callback;
     PerlCallback m_on_enable_action_buttons_callback;
     PerlCallback m_on_gizmo_scale_uniformly_callback;
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    PerlCallback m_on_gizmo_rotate_3D_callback;
+    PerlCallback m_on_gizmo_flatten_3D_callback;
+#else
     PerlCallback m_on_gizmo_rotate_callback;
     PerlCallback m_on_gizmo_flatten_callback;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
     PerlCallback m_on_update_geometry_info_callback;
 
     PerlCallback m_action_add_callback;
@@ -626,8 +646,13 @@ public:
     void register_on_wipe_tower_moved_callback(void* callback);
     void register_on_enable_action_buttons_callback(void* callback);
     void register_on_gizmo_scale_uniformly_callback(void* callback);
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    void register_on_gizmo_rotate_3D_callback(void* callback);
+    void register_on_gizmo_flatten_3D_callback(void* callback);
+#else
     void register_on_gizmo_rotate_callback(void* callback);
     void register_on_gizmo_flatten_callback(void* callback);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
     void register_on_update_geometry_info_callback(void* callback);
 
     void register_action_add_callback(void* callback);
diff --git a/src/slic3r/GUI/GLCanvas3DManager.cpp b/src/slic3r/GUI/GLCanvas3DManager.cpp
index 495f49425..1ac588f6c 100644
--- a/src/slic3r/GUI/GLCanvas3DManager.cpp
+++ b/src/slic3r/GUI/GLCanvas3DManager.cpp
@@ -699,6 +699,21 @@ void GLCanvas3DManager::register_on_gizmo_scale_uniformly_callback(wxGLCanvas* c
         it->second->register_on_gizmo_scale_uniformly_callback(callback);
 }
 
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+void GLCanvas3DManager::register_on_gizmo_rotate_3D_callback(wxGLCanvas* canvas, void* callback)
+{
+    CanvasesMap::iterator it = _get_canvas(canvas);
+    if (it != m_canvases.end())
+        it->second->register_on_gizmo_rotate_3D_callback(callback);
+}
+
+void GLCanvas3DManager::register_on_gizmo_flatten_3D_callback(wxGLCanvas* canvas, void* callback)
+{
+    CanvasesMap::iterator it = _get_canvas(canvas);
+    if (it != m_canvases.end())
+        it->second->register_on_gizmo_flatten_3D_callback(callback);
+}
+#else
 void GLCanvas3DManager::register_on_gizmo_rotate_callback(wxGLCanvas* canvas, void* callback)
 {
     CanvasesMap::iterator it = _get_canvas(canvas);
@@ -712,6 +727,7 @@ void GLCanvas3DManager::register_on_gizmo_flatten_callback(wxGLCanvas* canvas, v
     if (it != m_canvases.end())
         it->second->register_on_gizmo_flatten_callback(callback);
 }
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 
 void GLCanvas3DManager::register_on_update_geometry_info_callback(wxGLCanvas* canvas, void* callback)
 {
diff --git a/src/slic3r/GUI/GLCanvas3DManager.hpp b/src/slic3r/GUI/GLCanvas3DManager.hpp
index 4922b6171..2331ec3f5 100644
--- a/src/slic3r/GUI/GLCanvas3DManager.hpp
+++ b/src/slic3r/GUI/GLCanvas3DManager.hpp
@@ -163,8 +163,13 @@ public:
     void register_on_wipe_tower_moved_callback(wxGLCanvas* canvas, void* callback);
     void register_on_enable_action_buttons_callback(wxGLCanvas* canvas, void* callback);
     void register_on_gizmo_scale_uniformly_callback(wxGLCanvas* canvas, void* callback);
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    void register_on_gizmo_rotate_3D_callback(wxGLCanvas* canvas, void* callback);
+    void register_on_gizmo_flatten_3D_callback(wxGLCanvas* canvas, void* callback);
+#else
     void register_on_gizmo_rotate_callback(wxGLCanvas* canvas, void* callback);
     void register_on_gizmo_flatten_callback(wxGLCanvas* canvas, void* callback);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
     void register_on_update_geometry_info_callback(wxGLCanvas* canvas, void* callback);
 
     void register_action_add_callback(wxGLCanvas* canvas, void* callback);
diff --git a/src/slic3r/GUI/GLGizmo.cpp b/src/slic3r/GUI/GLGizmo.cpp
index e23958c1d..f9b481a31 100644
--- a/src/slic3r/GUI/GLGizmo.cpp
+++ b/src/slic3r/GUI/GLGizmo.cpp
@@ -759,6 +759,20 @@ void GLGizmoScale3D::on_update(const Linef3& mouse_ray)
         do_scale_uniform(mouse_ray);
 }
 
+#if ENABLE_GIZMOS_RESET
+void GLGizmoScale3D::on_process_double_click()
+{
+    if ((m_hover_id == 0) || (m_hover_id == 1))
+        m_scale(0) = 1.0;
+    else if ((m_hover_id == 2) || (m_hover_id == 3))
+        m_scale(1) = 1.0;
+    else if ((m_hover_id == 4) || (m_hover_id == 5))
+        m_scale(2) = 1.0;
+    else if (m_hover_id >= 6)
+        m_scale = Vec3d::Ones();
+}
+#endif // ENABLE_GIZMOS_RESET
+
 void GLGizmoScale3D::on_render(const BoundingBoxf3& box) const
 {
     if (m_grabbers[0].dragging || m_grabbers[1].dragging)
@@ -1237,15 +1251,28 @@ void GLGizmoFlatten::on_render(const BoundingBoxf3& box) const
             ::glColor4f(0.9f, 0.9f, 0.9f, 0.5f);
 
 #if ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+        for (const InstanceData& inst : m_instances) {
+            Vec3d position = inst.position + dragged_offset;
+#else
         for (Vec3d offset : m_instances_positions) {
             offset += dragged_offset;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 #else
         for (Vec2d offset : m_instances_positions) {
             offset += to_2d(dragged_offset);
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
             ::glPushMatrix();
 #if ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+            ::glTranslated(position(0), position(1), position(2));
+            ::glRotated(inst.rotation(2) * 180.0 / (double)PI, 0.0, 0.0, 1.0);
+            ::glRotated(inst.rotation(1) * 180.0 / (double)PI, 0.0, 1.0, 0.0);
+            ::glRotated(inst.rotation(0) * 180.0 / (double)PI, 1.0, 0.0, 0.0);
+            ::glScaled(inst.scaling_factor, inst.scaling_factor, inst.scaling_factor);
+#else
             ::glTranslated(offset(0), offset(1), offset(2));
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 #else
             ::glTranslatef((GLfloat)offset(0), (GLfloat)offset(1), 0.0f);
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
@@ -1268,13 +1295,25 @@ void GLGizmoFlatten::on_render_for_picking(const BoundingBoxf3& box) const
     {
         ::glColor3f(1.0f, 1.0f, picking_color_component(i));
 #if ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+        for (const InstanceData& inst : m_instances) {
+#else
         for (const Vec3d& offset : m_instances_positions) {
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 #else
         for (const Vec2d& offset : m_instances_positions) {
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
             ::glPushMatrix();
 #if ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+            ::glTranslated(inst.position(0), inst.position(1), inst.position(2));
+            ::glRotated(inst.rotation(2) * 180.0 / (double)PI, 0.0, 0.0, 1.0);
+            ::glRotated(inst.rotation(1) * 180.0 / (double)PI, 0.0, 1.0, 0.0);
+            ::glRotated(inst.rotation(0) * 180.0 / (double)PI, 1.0, 0.0, 0.0);
+            ::glScaled(inst.scaling_factor, inst.scaling_factor, inst.scaling_factor);
+#else
             ::glTranslated(offset(0), offset(1), offset(2));
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 #else
             ::glTranslatef((GLfloat)offset(0), (GLfloat)offset(1), 0.0f);
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
@@ -1293,10 +1332,18 @@ void GLGizmoFlatten::set_flattening_data(const ModelObject* model_object)
 
     // ...and save the updated positions of the object instances:
     if (m_model_object && !m_model_object->instances.empty()) {
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+        m_instances.clear();
+#else
         m_instances_positions.clear();
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
         for (const auto* instance : m_model_object->instances)
 #if ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+            m_instances.emplace_back(instance->get_offset(), instance->get_rotation(), instance->scaling_factor);
+#else
             m_instances_positions.emplace_back(instance->get_offset());
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 #else
             m_instances_positions.emplace_back(instance->offset);
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
@@ -1312,8 +1359,10 @@ void GLGizmoFlatten::update_planes()
     for (const ModelVolume* vol : m_model_object->volumes)
         ch.merge(vol->get_convex_hull());
     ch = ch.convex_hull_3d();
+#if !ENABLE_MODELINSTANCE_3D_ROTATION
     ch.scale(m_model_object->instances.front()->scaling_factor);
     ch.rotate_z(m_model_object->instances.front()->rotation);
+#endif // !ENABLE_MODELINSTANCE_3D_ROTATION
 
     m_planes.clear();
 
@@ -1358,8 +1407,8 @@ void GLGizmoFlatten::update_planes()
         // if this is a just a very small triangle, remove it to speed up further calculations (it would be rejected anyway):
         if (m_planes.back().vertices.size() == 3 &&
                (m_planes.back().vertices[0] - m_planes.back().vertices[1]).norm() < 1.f
-            || (m_planes.back().vertices[0] - m_planes.back().vertices[2]).norm() < 1.f)
-            m_planes.pop_back();
+               || (m_planes.back().vertices[0] - m_planes.back().vertices[2]).norm() < 1.f)
+               m_planes.pop_back();
     }
 
     // Now we'll go through all the polygons, transform the points into xy plane to process them:
@@ -1462,8 +1511,10 @@ void GLGizmoFlatten::update_planes()
     m_source_data.bounding_boxes.clear();
     for (const auto& vol : m_model_object->volumes)
         m_source_data.bounding_boxes.push_back(vol->get_convex_hull().bounding_box());
+#if !ENABLE_MODELINSTANCE_3D_ROTATION
     m_source_data.scaling_factor = m_model_object->instances.front()->scaling_factor;
     m_source_data.rotation = m_model_object->instances.front()->rotation;
+#endif // !ENABLE_MODELINSTANCE_3D_ROTATION
     const float* first_vertex = m_model_object->volumes.front()->get_convex_hull().first_vertex();
     m_source_data.mesh_first_point = Vec3d((double)first_vertex[0], (double)first_vertex[1], (double)first_vertex[2]);
 }
@@ -1475,10 +1526,14 @@ bool GLGizmoFlatten::is_plane_update_necessary() const
     if (m_state != On || !m_model_object || m_model_object->instances.empty())
         return false;
 
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    if (m_model_object->volumes.size() != m_source_data.bounding_boxes.size())
+#else
     if (m_model_object->volumes.size() != m_source_data.bounding_boxes.size()
      || m_model_object->instances.front()->scaling_factor != m_source_data.scaling_factor
      || m_model_object->instances.front()->rotation != m_source_data.rotation)
-         return true;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
+        return true;
 
     // now compare the bounding boxes:
     for (unsigned int i=0; i<m_model_object->volumes.size(); ++i)
@@ -1493,11 +1548,22 @@ bool GLGizmoFlatten::is_plane_update_necessary() const
     return false;
 }
 
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+Vec3d GLGizmoFlatten::get_flattening_rotation() const
+{
+    // calculates the rotations in model space
+    Eigen::Quaterniond q;
+    Vec3d angles = q.setFromTwoVectors(m_normal, -Vec3d::UnitZ()).toRotationMatrix().eulerAngles(2, 1, 0);
+    m_normal = Vec3d::Zero();
+    return Vec3d(angles(2), angles(1), angles(0));
+}
+#else
 Vec3d GLGizmoFlatten::get_flattening_normal() const {
     Vec3d normal = m_model_object->instances.front()->world_matrix(true).matrix().block(0, 0, 3, 3).inverse() * m_normal;
     m_normal = Vec3d::Zero();
     return normal.normalized();
 }
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 
 } // namespace GUI
 } // namespace Slic3r
diff --git a/src/slic3r/GUI/GLGizmo.hpp b/src/slic3r/GUI/GLGizmo.hpp
index 2430b5af5..e0f2c73d0 100644
--- a/src/slic3r/GUI/GLGizmo.hpp
+++ b/src/slic3r/GUI/GLGizmo.hpp
@@ -94,6 +94,10 @@ public:
 
     void update(const Linef3& mouse_ray);
 
+#if ENABLE_GIZMOS_RESET
+    void process_double_click() { on_process_double_click(); }
+#endif // ENABLE_GIZMOS_RESET
+
     void render(const BoundingBoxf3& box) const { on_render(box); }
     void render_for_picking(const BoundingBoxf3& box) const { on_render_for_picking(box); }
 
@@ -106,6 +110,9 @@ protected:
     virtual void on_start_dragging(const BoundingBoxf3& box) {}
     virtual void on_stop_dragging() {}
     virtual void on_update(const Linef3& mouse_ray) = 0;
+#if ENABLE_GIZMOS_RESET
+    virtual void on_process_double_click() {}
+#endif // ENABLE_GIZMOS_RESET
     virtual void on_render(const BoundingBoxf3& box) const = 0;
     virtual void on_render_for_picking(const BoundingBoxf3& box) const = 0;
 
@@ -155,6 +162,9 @@ protected:
     virtual bool on_init();
     virtual void on_start_dragging(const BoundingBoxf3& box);
     virtual void on_update(const Linef3& mouse_ray);
+#if ENABLE_GIZMOS_RESET
+    virtual void on_process_double_click() { m_angle = 0.0; }
+#endif // ENABLE_GIZMOS_RESET
     virtual void on_render(const BoundingBoxf3& box) const;
     virtual void on_render_for_picking(const BoundingBoxf3& box) const;
 
@@ -178,6 +188,10 @@ class GLGizmoRotate3D : public GLGizmoBase
 public:
     explicit GLGizmoRotate3D(GLCanvas3D& parent);
 
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    Vec3d get_rotation() const { return Vec3d(m_gizmos[X].get_angle(), m_gizmos[Y].get_angle(), m_gizmos[Z].get_angle()); }
+    void set_rotation(const Vec3d& rotation) { m_gizmos[X].set_angle(rotation(0)); m_gizmos[Y].set_angle(rotation(1)); m_gizmos[Z].set_angle(rotation(2)); }
+#else
     double get_angle_x() const { return m_gizmos[X].get_angle(); }
     void set_angle_x(double angle) { m_gizmos[X].set_angle(angle); }
 
@@ -186,6 +200,7 @@ public:
 
     double get_angle_z() const { return m_gizmos[Z].get_angle(); }
     void set_angle_z(double angle) { m_gizmos[Z].set_angle(angle); }
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 
 protected:
     virtual bool on_init();
@@ -222,6 +237,13 @@ protected:
             g.update(mouse_ray);
         }
     }
+#if ENABLE_GIZMOS_RESET
+    virtual void on_process_double_click()
+    {
+        if (m_hover_id != -1)
+            m_gizmos[m_hover_id].process_double_click();
+    }
+#endif // ENABLE_GIZMOS_RESET
     virtual void on_render(const BoundingBoxf3& box) const;
     virtual void on_render_for_picking(const BoundingBoxf3& box) const
     {
@@ -265,6 +287,9 @@ protected:
     virtual void on_start_dragging(const BoundingBoxf3& box);
     virtual void on_stop_dragging() { m_show_starting_box = false; }
     virtual void on_update(const Linef3& mouse_ray);
+#if ENABLE_GIZMOS_RESET
+    virtual void on_process_double_click();
+#endif // ENABLE_GIZMOS_RESET
     virtual void on_render(const BoundingBoxf3& box) const;
     virtual void on_render_for_picking(const BoundingBoxf3& box) const;
 
@@ -320,8 +345,10 @@ private:
     };
     struct SourceDataSummary {
         std::vector<BoundingBoxf3> bounding_boxes; // bounding boxes of convex hulls of individual volumes
+#if !ENABLE_MODELINSTANCE_3D_ROTATION
         float scaling_factor;
         float rotation;
+#endif // !ENABLE_MODELINSTANCE_3D_ROTATION
         Vec3d mesh_first_point;
     };
 
@@ -330,7 +357,19 @@ private:
 
     std::vector<PlaneData> m_planes;
 #if ENABLE_MODELINSTANCE_3D_OFFSET
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    struct InstanceData
+    {
+        Vec3d position;
+        Vec3d rotation; 
+        double scaling_factor;
+
+        InstanceData(const Vec3d& position, const Vec3d& rotation, double scaling_factor) : position(position), rotation(rotation), scaling_factor(scaling_factor) {}
+    };
+    std::vector<InstanceData> m_instances;
+#else
     Pointf3s m_instances_positions;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 #else
     std::vector<Vec2d> m_instances_positions;
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
@@ -344,7 +383,11 @@ public:
     explicit GLGizmoFlatten(GLCanvas3D& parent);
 
     void set_flattening_data(const ModelObject* model_object);
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    Vec3d get_flattening_rotation() const;
+#else
     Vec3d get_flattening_normal() const;
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 
 protected:
     virtual bool on_init();
diff --git a/src/slic3r/GUI/GUI.cpp b/src/slic3r/GUI/GUI.cpp
index e5ed917b3..2ad155b7d 100644
--- a/src/slic3r/GUI/GUI.cpp
+++ b/src/slic3r/GUI/GUI.cpp
@@ -1,4 +1,5 @@
 #include "GUI.hpp"
+#include "../AppController.hpp"
 #include "WipeTowerDialog.hpp"
 
 #include <assert.h>
@@ -1405,4 +1406,23 @@ void desktop_open_datadir_folder()
 #endif
 }
 
+namespace {
+AppControllerPtr g_appctl;
+}
+
+AppControllerPtr get_appctl()
+{
+    return g_appctl;
+}
+
+void set_cli_appctl()
+{
+    g_appctl = std::make_shared<AppControllerCli>();
+}
+
+void set_gui_appctl()
+{
+    g_appctl = std::make_shared<AppControllerGui>();
+}
+
 } }
diff --git a/src/slic3r/GUI/GUI.hpp b/src/slic3r/GUI/GUI.hpp
index 9b2fce5b4..7f470432d 100644
--- a/src/slic3r/GUI/GUI.hpp
+++ b/src/slic3r/GUI/GUI.hpp
@@ -42,6 +42,9 @@ class TabIface;
 class PreviewIface;
 class Print;
 class GCodePreviewData;
+class AppControllerBase;
+
+using AppControllerPtr = std::shared_ptr<AppControllerBase>;
 
 #define _(s)    Slic3r::GUI::I18N::translate((s))
 
@@ -129,6 +132,10 @@ ProgressStatusBar* get_progress_status_bar();
 wxNotebook *	get_tab_panel();
 wxNotebook*		get_tab_panel();
 
+AppControllerPtr get_appctl();
+void             set_cli_appctl();
+void             set_gui_appctl();
+
 const wxColour& get_label_clr_modified();
 const wxColour& get_label_clr_sys();
 const wxColour& get_label_clr_default();
diff --git a/src/slic3r/GUI/GUI_ObjectParts.cpp b/src/slic3r/GUI/GUI_ObjectParts.cpp
index 4fc3b88c0..96483721b 100644
--- a/src/slic3r/GUI/GUI_ObjectParts.cpp
+++ b/src/slic3r/GUI/GUI_ObjectParts.cpp
@@ -1802,11 +1802,15 @@ void update_scale_values(double scaling_factor)
 
 void update_rotation_values()
 {
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    update_rotation_value((*m_objects)[m_selected_object_id]->instances.front()->get_rotation());
+#else
     auto og = get_optgroup(ogFrequentlyObjectSettings);
     auto instance = (*m_objects)[m_selected_object_id]->instances.front();
     og->set_value("rotation_x", 0);
     og->set_value("rotation_y", 0);
     og->set_value("rotation_z", int(Geometry::rad2deg(instance->rotation)));
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 }
 
 void update_rotation_value(double angle, Axis axis)
@@ -1836,6 +1840,16 @@ void update_rotation_value(double angle, Axis axis)
     og->set_value(axis_str, int(Geometry::rad2deg(angle)));
 }
 
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+void update_rotation_value(const Vec3d& rotation)
+{
+    auto og = get_optgroup(ogFrequentlyObjectSettings);
+    og->set_value("rotation_x", int(Geometry::rad2deg(rotation(0))));
+    og->set_value("rotation_y", int(Geometry::rad2deg(rotation(1))));
+    og->set_value("rotation_z", int(Geometry::rad2deg(rotation(2))));
+}
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
+
 void set_uniform_scaling(const bool uniform_scale)
 {
     g_is_uniform_scale = uniform_scale;
diff --git a/src/slic3r/GUI/GUI_ObjectParts.hpp b/src/slic3r/GUI/GUI_ObjectParts.hpp
index e66b4d1db..fdeb7a629 100644
--- a/src/slic3r/GUI/GUI_ObjectParts.hpp
+++ b/src/slic3r/GUI/GUI_ObjectParts.hpp
@@ -124,6 +124,9 @@ void update_scale_values(double scaling_factor);
 void update_rotation_values();
 // update rotation value after "gizmos"
 void update_rotation_value(double angle, Axis axis);
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+void update_rotation_value(const Vec3d& rotation);
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
 void set_uniform_scaling(const bool uniform_scale);
 
 void on_begin_drag(wxDataViewEvent &event);
diff --git a/src/slic3r/GUI/GUI_Preview.cpp b/src/slic3r/GUI/GUI_Preview.cpp
index bfc8b5623..c66d1fd1f 100644
--- a/src/slic3r/GUI/GUI_Preview.cpp
+++ b/src/slic3r/GUI/GUI_Preview.cpp
@@ -152,20 +152,20 @@ bool Preview::init(wxNotebook* notebook, DynamicPrintConfig* config, Print* prin
     bind_event_handlers();
     
     // sets colors for gcode preview extrusion roles
-    std::vector<std::string>  extrusion_roles_colors = {
-        "FFFF66", // Perimeter 
-        "FFA500", // External perimeter
-        "0000FF", // Overhang perimeter
-        "B1302A", // Internal infill
-        "D732D7", // Solid infill
-        "FF1A1A", // Top solid infill
-        "9999FF", // Bridge infill
-        "FFFFFF", // Gap fill
-        "845321", // Skirt
-        "00FF00", // Support material
-        "008000", // Support material interface
-        "B3E3AB", // Wipe tower
-        "28CC94" // Custom
+    std::vector<std::string> extrusion_roles_colors = {
+        "Perimeter", "FFFF66",
+        "External perimeter", "FFA500",
+        "Overhang perimeter", "0000FF",
+        "Internal infill", "B1302A",
+        "Solid infill", "D732D7",
+        "Top solid infill", "FF1A1A",
+        "Bridge infill", "9999FF",
+        "Gap fill", "FFFFFF",
+        "Skirt", "845321",
+        "Support material", "00FF00",
+        "Support material interface", "008000",
+        "Wipe tower", "B3E3AB",
+        "Custom", "28CC94"
     };
     m_gcode_preview_data->set_extrusion_paths_colors(extrusion_roles_colors);
 
diff --git a/src/slic3r/GUI/ProgressIndicator.hpp b/src/slic3r/GUI/ProgressIndicator.hpp
index 0cf8b4a17..280ba63ac 100644
--- a/src/slic3r/GUI/ProgressIndicator.hpp
+++ b/src/slic3r/GUI/ProgressIndicator.hpp
@@ -14,31 +14,31 @@ public:
     using CancelFn = std::function<void(void)>; // Cancel function signature.
 
 private:
-    float state_ = .0f, max_ = 1.f, step_;
-    CancelFn cancelfunc_ = [](){};
+    float m_state = .0f, m_max = 1.f, m_step;
+    CancelFn m_cancelfunc = [](){};
 
 public:
 
     inline virtual ~ProgressIndicator() {}
 
     /// Get the maximum of the progress range.
-    float max() const { return max_; }
+    float max() const { return m_max; }
 
     /// Get the current progress state
-    float state() const { return state_; }
+    float state() const { return m_state; }
 
     /// Set the maximum of the progress range
-    virtual void max(float maxval) { max_ = maxval; }
+    virtual void max(float maxval) { m_max = maxval; }
 
     /// Set the current state of the progress.
-    virtual void state(float val)  { state_ = val; }
+    virtual void state(float val)  { m_state = val; }
 
     /**
      * @brief Number of states int the progress. Can be used instead of giving a
      * maximum value.
      */
     virtual void states(unsigned statenum) {
-        step_ = max_ / statenum;
+        m_step = m_max / statenum;
     }
 
     /// Message shown on the next status update.
@@ -51,13 +51,13 @@ public:
     virtual void message_fmt(const std::string& fmt, ...);
 
     /// Set up a cancel callback for the operation if feasible.
-    virtual void on_cancel(CancelFn func = CancelFn()) { cancelfunc_ = func; }
+    virtual void on_cancel(CancelFn func = CancelFn()) { m_cancelfunc = func; }
 
     /**
      * Explicitly shut down the progress indicator and call the associated
      * callback.
      */
-    virtual void cancel() { cancelfunc_(); }
+    virtual void cancel() { m_cancelfunc(); }
 
     /// Convenience function to call message and status update in one function.
     void update(float st, const std::string& msg) {
diff --git a/src/slic3r/GUI/ProgressStatusBar.cpp b/src/slic3r/GUI/ProgressStatusBar.cpp
index 363e34cb2..0ca86084b 100644
--- a/src/slic3r/GUI/ProgressStatusBar.cpp
+++ b/src/slic3r/GUI/ProgressStatusBar.cpp
@@ -14,117 +14,117 @@ namespace Slic3r {
 ProgressStatusBar::ProgressStatusBar(wxWindow *parent, int id):
     self(new wxStatusBar(parent ? parent : GUI::get_main_frame(),
                          id == -1? wxID_ANY : id)),
-    timer_(new wxTimer(self)),
-    prog_ (new wxGauge(self,
+    m_timer(new wxTimer(self)),
+    m_prog (new wxGauge(self,
                        wxGA_HORIZONTAL,
                        100,
                        wxDefaultPosition,
                        wxDefaultSize)),
-    cancelbutton_(new wxButton(self,
+    m_cancelbutton(new wxButton(self,
                                -1,
                                "Cancel",
                                wxDefaultPosition,
                                wxDefaultSize))
 {
-    prog_->Hide();
-    cancelbutton_->Hide();
+    m_prog->Hide();
+    m_cancelbutton->Hide();
 
     self->SetFieldsCount(3);
     int w[] = {-1, 150, 155};
     self->SetStatusWidths(3, w);
 
     self->Bind(wxEVT_TIMER, [this](const wxTimerEvent&) {
-        if (prog_->IsShown()) timer_->Stop();
-        if(is_busy()) prog_->Pulse();
+        if (m_prog->IsShown()) m_timer->Stop();
+        if(is_busy()) m_prog->Pulse();
     });
 
     self->Bind(wxEVT_SIZE, [this](wxSizeEvent& event){
         wxRect rect;
         self->GetFieldRect(1, rect);
         auto offset = 0;
-        cancelbutton_->Move(rect.GetX() + offset, rect.GetY() + offset);
-        cancelbutton_->SetSize(rect.GetWidth() - offset, rect.GetHeight());
+        m_cancelbutton->Move(rect.GetX() + offset, rect.GetY() + offset);
+        m_cancelbutton->SetSize(rect.GetWidth() - offset, rect.GetHeight());
 
         self->GetFieldRect(2, rect);
-        prog_->Move(rect.GetX() + offset, rect.GetY() + offset);
-        prog_->SetSize(rect.GetWidth() - offset, rect.GetHeight());
+        m_prog->Move(rect.GetX() + offset, rect.GetY() + offset);
+        m_prog->SetSize(rect.GetWidth() - offset, rect.GetHeight());
 
         event.Skip();
     });
 
-    cancelbutton_->Bind(wxEVT_BUTTON, [this](const wxCommandEvent&) {
-        if(cancel_cb_) cancel_cb_();
+    m_cancelbutton->Bind(wxEVT_BUTTON, [this](const wxCommandEvent&) {
+        if(m_cancel_cb) m_cancel_cb();
         m_perl_cancel_callback.call();
-        cancelbutton_->Hide();
+        m_cancelbutton->Hide();
     });
 }
 
 ProgressStatusBar::~ProgressStatusBar() {
-    if(timer_->IsRunning()) timer_->Stop();
+    if(m_timer->IsRunning()) m_timer->Stop();
 }
 
 int ProgressStatusBar::get_progress() const
 {
-    return prog_->GetValue();
+    return m_prog->GetValue();
 }
 
 void ProgressStatusBar::set_progress(int val)
 {
-    if(!prog_->IsShown()) show_progress(true);
+    if(!m_prog->IsShown()) show_progress(true);
 
-    if(val == prog_->GetRange()) {
-        prog_->SetValue(0);
+    if(val == m_prog->GetRange()) {
+        m_prog->SetValue(0);
         show_progress(false);
     } else {
-        prog_->SetValue(val);
+        m_prog->SetValue(val);
     }
 }
 
 int ProgressStatusBar::get_range() const
 {
-    return prog_->GetRange();
+    return m_prog->GetRange();
 }
 
 void ProgressStatusBar::set_range(int val)
 {
-    if(val != prog_->GetRange()) {
-        prog_->SetRange(val);
+    if(val != m_prog->GetRange()) {
+        m_prog->SetRange(val);
     }
 }
 
 void ProgressStatusBar::show_progress(bool show)
 {
-    prog_->Show(show);
-    prog_->Pulse();
+    m_prog->Show(show);
+    m_prog->Pulse();
 }
 
 void ProgressStatusBar::start_busy(int rate)
 {
-    busy_ = true;
+    m_busy = true;
     show_progress(true);
-    if (!timer_->IsRunning()) {
-        timer_->Start(rate);
+    if (!m_timer->IsRunning()) {
+        m_timer->Start(rate);
     }
 }
 
 void ProgressStatusBar::stop_busy()
 {
-    timer_->Stop();
+    m_timer->Stop();
     show_progress(false);
-    prog_->SetValue(0);
-    busy_ = false;
+    m_prog->SetValue(0);
+    m_busy = false;
 }
 
 void ProgressStatusBar::set_cancel_callback(ProgressStatusBar::CancelFn ccb) {
-    cancel_cb_ = ccb;
-    if(ccb) cancelbutton_->Show();
-    else cancelbutton_->Hide();
+    m_cancel_cb = ccb;
+    if(ccb) m_cancelbutton->Show();
+    else m_cancelbutton->Hide();
 }
 
 void ProgressStatusBar::run(int rate)
 {
-    if(!timer_->IsRunning()) {
-        timer_->Start(rate);
+    if(!m_timer->IsRunning()) {
+        m_timer->Start(rate);
     }
 }
 
@@ -141,12 +141,12 @@ void ProgressStatusBar::set_status_text(const wxString& txt)
 
 void ProgressStatusBar::show_cancel_button()
 {
-    cancelbutton_->Show();
+    m_cancelbutton->Show();
 }
 
 void ProgressStatusBar::hide_cancel_button()
 {
-    cancelbutton_->Hide();
+    m_cancelbutton->Hide();
 }
 
 }
diff --git a/src/slic3r/GUI/ProgressStatusBar.hpp b/src/slic3r/GUI/ProgressStatusBar.hpp
index 7c2171a5e..57ec9ae2b 100644
--- a/src/slic3r/GUI/ProgressStatusBar.hpp
+++ b/src/slic3r/GUI/ProgressStatusBar.hpp
@@ -24,9 +24,9 @@ namespace Slic3r {
  */
 class ProgressStatusBar {
     wxStatusBar *self;      // we cheat! It should be the base class but: perl!
-    wxTimer *timer_;
-    wxGauge *prog_;
-    wxButton *cancelbutton_;
+    wxTimer *m_timer;
+    wxGauge *m_prog;
+    wxButton *m_cancelbutton;
 public:
 
     /// Cancel callback function type
@@ -42,7 +42,7 @@ public:
     void show_progress(bool);
     void start_busy(int = 100);
     void stop_busy();
-    inline bool is_busy() const { return busy_; }
+    inline bool is_busy() const { return m_busy; }
     void set_cancel_callback(CancelFn = CancelFn());
     inline void remove_cancel_callback() { set_cancel_callback(); }
     void run(int rate);
@@ -55,8 +55,8 @@ public:
 
     PerlCallback m_perl_cancel_callback;
 private:
-    bool busy_ = false;
-    CancelFn cancel_cb_;
+    bool m_busy = false;
+    CancelFn m_cancel_cb;
 };
 
 namespace GUI {
diff --git a/xs/xsp/GUI.xsp b/xs/xsp/GUI.xsp
index 22e2ff1d7..a1e3e4670 100644
--- a/xs/xsp/GUI.xsp
+++ b/xs/xsp/GUI.xsp
@@ -35,6 +35,12 @@ bool is_windows10()
 void set_wxapp(SV *ui)
     %code%{ Slic3r::GUI::set_wxapp((wxApp*)wxPli_sv_2_object(aTHX_ ui, "Wx::App")); %};
 
+void set_gui_appctl()
+    %code%{ Slic3r::GUI::set_gui_appctl(); %};
+
+void set_cli_appctl()
+    %code%{ Slic3r::GUI::set_cli_appctl(); %};
+
 void set_progress_status_bar(ProgressStatusBar *prs)
     %code%{ Slic3r::GUI::set_progress_status_bar(prs); %};
 
diff --git a/xs/xsp/GUI_3DScene.xsp b/xs/xsp/GUI_3DScene.xsp
index c3e4ba3b7..0a3d11ed6 100644
--- a/xs/xsp/GUI_3DScene.xsp
+++ b/xs/xsp/GUI_3DScene.xsp
@@ -652,6 +652,13 @@ register_on_gizmo_rotate_callback(canvas, callback)
         _3DScene::register_on_gizmo_rotate_callback((wxGLCanvas*)wxPli_sv_2_object(aTHX_ canvas, "Wx::GLCanvas"), (void*)callback);
 
 void
+register_on_gizmo_rotate_3D_callback(canvas, callback)
+        SV *canvas;
+        SV *callback;
+    CODE:
+        _3DScene::register_on_gizmo_rotate_3D_callback((wxGLCanvas*)wxPli_sv_2_object(aTHX_ canvas, "Wx::GLCanvas"), (void*)callback);
+
+void
 register_on_gizmo_flatten_callback(canvas, callback)
         SV *canvas;
         SV *callback;
@@ -659,6 +666,13 @@ register_on_gizmo_flatten_callback(canvas, callback)
         _3DScene::register_on_gizmo_flatten_callback((wxGLCanvas*)wxPli_sv_2_object(aTHX_ canvas, "Wx::GLCanvas"), (void*)callback);
 
 void
+register_on_gizmo_flatten_3D_callback(canvas, callback)
+        SV *canvas;
+        SV *callback;
+    CODE:
+        _3DScene::register_on_gizmo_flatten_3D_callback((wxGLCanvas*)wxPli_sv_2_object(aTHX_ canvas, "Wx::GLCanvas"), (void*)callback);
+
+void
 register_on_update_geometry_info_callback(canvas, callback)
         SV *canvas;
         SV *callback;
diff --git a/xs/xsp/Model.xsp b/xs/xsp/Model.xsp
index 101faf564..892ecd861 100644
--- a/xs/xsp/Model.xsp
+++ b/xs/xsp/Model.xsp
@@ -364,8 +364,13 @@ ModelMaterial::attributes()
     Ref<ModelObject> object()
         %code%{ RETVAL = THIS->get_object(); %};
 
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    double rotation()
+        %code%{ RETVAL = THIS->get_rotation(Z); %};
+#else
     double rotation()
         %code%{ RETVAL = THIS->rotation; %};
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
     double scaling_factor()
         %code%{ RETVAL = THIS->scaling_factor; %};
 #if ENABLE_MODELINSTANCE_3D_OFFSET
@@ -376,8 +381,17 @@ ModelMaterial::attributes()
         %code%{ RETVAL = &THIS->offset; %};
 #endif // ENABLE_MODELINSTANCE_3D_OFFSET
 
+#if ENABLE_MODELINSTANCE_3D_ROTATION
+    void set_rotation(double val)
+        %code%{ THIS->set_rotation(Z, val); THIS->get_object()->invalidate_bounding_box(); %};
+        
+    void set_rotations(Vec3d *rotation)
+        %code%{ THIS->set_rotation(*rotation); THIS->get_object()->invalidate_bounding_box(); %};
+        
+#else
     void set_rotation(double val)
         %code%{ THIS->rotation = val; THIS->get_object()->invalidate_bounding_box(); %};
+#endif // ENABLE_MODELINSTANCE_3D_ROTATION
     void set_scaling_factor(double val)
         %code%{ THIS->scaling_factor = val; THIS->get_object()->invalidate_bounding_box(); %};
 #if ENABLE_MODELINSTANCE_3D_OFFSET