Generic subparts placed at one of the bottom corners of the world bounding box of the transformed current selected instance (#1517)

src/libslic3r/Model.cpp

@@ -819,14 +819,27 @@ TriangleMesh ModelObject::full_raw_mesh() const
 BoundingBoxf3 ModelObject::raw_bounding_box() const
 {
     BoundingBoxf3 bb;
-    for (const ModelVolume *v : this->volumes)
+#if ENABLE_GENERIC_SUBPARTS_PLACEMENT
-        if (v->is_model_part()) {
     if (this->instances.empty())
         throw std::invalid_argument("Can't call raw_bounding_box() with no instances");
 
+    const Transform3d& inst_matrix = this->instances.front()->get_transformation().get_matrix(true);
+#endif // ENABLE_GENERIC_SUBPARTS_PLACEMENT
+    for (const ModelVolume *v : this->volumes)
+        if (v->is_model_part()) {
+#if !ENABLE_GENERIC_SUBPARTS_PLACEMENT
+            if (this->instances.empty())
+                throw std::invalid_argument("Can't call raw_bounding_box() with no instances");
+#endif // !ENABLE_GENERIC_SUBPARTS_PLACEMENT
+
             TriangleMesh vol_mesh(v->mesh);
+#if ENABLE_GENERIC_SUBPARTS_PLACEMENT
+            vol_mesh.transform(inst_matrix * v->get_matrix());
+            bb.merge(vol_mesh.bounding_box());
+#else
             vol_mesh.transform(v->get_matrix());
             bb.merge(this->instances.front()->transform_mesh_bounding_box(vol_mesh, true));
+#endif // ENABLE_GENERIC_SUBPARTS_PLACEMENT
         }
     return bb;
 }
@@ -835,13 +848,21 @@ BoundingBoxf3 ModelObject::raw_bounding_box() const
 BoundingBoxf3 ModelObject::instance_bounding_box(size_t instance_idx, bool dont_translate) const
 {
     BoundingBoxf3 bb;
+#if ENABLE_GENERIC_SUBPARTS_PLACEMENT
+    const Transform3d& inst_matrix = this->instances[instance_idx]->get_transformation().get_matrix(dont_translate);
+#endif // ENABLE_GENERIC_SUBPARTS_PLACEMENT
     for (ModelVolume *v : this->volumes)
     {
         if (v->is_model_part())
         {
             TriangleMesh mesh(v->mesh);
+#if ENABLE_GENERIC_SUBPARTS_PLACEMENT
+            mesh.transform(inst_matrix * v->get_matrix());
+            bb.merge(mesh.bounding_box());
+#else
             mesh.transform(v->get_matrix());
             bb.merge(this->instances[instance_idx]->transform_mesh_bounding_box(mesh, dont_translate));
+#endif // ENABLE_GENERIC_SUBPARTS_PLACEMENT
         }
     }
     return bb;

src/libslic3r/Technologies.hpp

@@ -58,3 +58,5 @@
 #define ENABLE_NEW_EULER_ANGLES (1 && ENABLE_1_42_0_ALPHA4)
 // Added minimum threshold for click and drag movements
 #define ENABLE_MOVE_MIN_THRESHOLD (1 && ENABLE_1_42_0_ALPHA4)
+// Modified initial default placement of generic subparts
+#define ENABLE_GENERIC_SUBPARTS_PLACEMENT (1 && ENABLE_1_42_0_ALPHA4)

src/slic3r/GUI/GUI_ObjectList.cpp

@@ -895,9 +895,29 @@ void ObjectList::load_generic_subobject(const std::string& type_name, const int
     auto new_volume = (*m_objects)[obj_idx]->add_volume(mesh);
     new_volume->set_type(static_cast<ModelVolume::Type>(type));
 
+#if !ENABLE_GENERIC_SUBPARTS_PLACEMENT
     new_volume->set_offset(Vec3d(0.0, 0.0, (*m_objects)[obj_idx]->origin_translation(2) - mesh.stl.stats.min(2)));
+#endif // !ENABLE_GENERIC_SUBPARTS_PLACEMENT
     new_volume->center_geometry();
 
+#if ENABLE_GENERIC_SUBPARTS_PLACEMENT
+    const GLCanvas3D::Selection& selection = wxGetApp().plater()->canvas3D()->get_selection();
+    int instance_idx = selection.get_instance_idx();
+    if (instance_idx != -1)
+    {
+        const GLVolume* v = selection.get_volume(*selection.get_volume_idxs().begin());
+        const Transform3d& inst_m = v->get_instance_transformation().get_matrix(true);
+        TriangleMesh vol_mesh(mesh);
+        vol_mesh.transform(inst_m);
+        Vec3d vol_shift = -vol_mesh.bounding_box().center();
+        vol_mesh.translate((float)vol_shift(0), (float)vol_shift(1), (float)vol_shift(2));
+        Vec3d world_mesh_bb_size = vol_mesh.bounding_box().size();
+        BoundingBoxf3 inst_bb = (*m_objects)[obj_idx]->instance_bounding_box(instance_idx);
+        Vec3d world_target = Vec3d(inst_bb.max(0), inst_bb.min(1), inst_bb.min(2)) + 0.5 * world_mesh_bb_size;
+        new_volume->set_offset(inst_m.inverse() * (world_target - v->get_instance_offset()));
+    }
+#endif // ENABLE_GENERIC_SUBPARTS_PLACEMENT
+
     new_volume->name = name;
     // set a default extruder value, since user can't add it manually
     new_volume->config.set_key_value("extruder", new ConfigOptionInt(0));