Rearrange code a little bit to make it more reusable

src/libslic3r/CutUtils.cpp

@@ -14,27 +14,6 @@ namespace Slic3r {
 
 using namespace Geometry;
 
-// Remap painting data from saved source to a cut result mesh, and set on a volume.
-static void remap_and_set_painting(ModelVolume* vol, const std::optional<TriangleSelector::SavedPainting>& saved)
-{
-    if (!saved) {
-        return;
-    }
-
-    auto remap_one = [&](const TriangleSelector::TriangleSplittingData& src_data,
-                         FacetsAnnotation& target_facets) {
-        if (src_data.bitstream.empty())
-            return;
-        auto result = TriangleSelector::remap_painting(saved->mesh.its, src_data, vol->mesh().its, translation_transform(vol->mesh().get_init_shift()));
-        if (!result.bitstream.empty())
-            target_facets.set_data(result);
-    };
-    remap_one(saved->supported, vol->supported_facets);
-    remap_one(saved->seam,      vol->seam_facets);
-    remap_one(saved->mmu,       vol->mmu_segmentation_facets);
-    remap_one(saved->fuzzy,     vol->fuzzy_skin_facets);
-}
-
 static void apply_tolerance(ModelVolume* vol)
 {
     ModelVolume::CutInfo& cut_info = vol->cut_info;
@@ -213,24 +192,24 @@ static void process_solid_part_cut(ModelVolume* volume, const Transform3d& insta
     if (attributes.has(ModelObjectCutAttribute::KeepAsParts)) {
         if (!upper_mesh.empty()) {
             add_cut_volume(upper_mesh, upper, volume, cut_matrix, "_A");
-            remap_and_set_painting(upper->volumes.back(), saved_painting);
+            upper->volumes.back()->restore_painting(saved_painting);
         }
         if (!lower_mesh.empty()) {
             add_cut_volume(lower_mesh, upper, volume, cut_matrix, "_B");
             upper->volumes.back()->cut_info.is_from_upper = false;
-            remap_and_set_painting(upper->volumes.back(), saved_painting);
+            upper->volumes.back()->restore_painting(saved_painting);
         }
         return;
     }
 
     if (attributes.has(ModelObjectCutAttribute::KeepUpper) && !upper_mesh.empty()) {
         add_cut_volume(upper_mesh, upper, volume, cut_matrix);
-        remap_and_set_painting(upper->volumes.back(), saved_painting);
+        upper->volumes.back()->restore_painting(saved_painting);
     }
 
     if (attributes.has(ModelObjectCutAttribute::KeepLower) && !lower_mesh.empty()) {
         add_cut_volume(lower_mesh, lower, volume, cut_matrix);
-        remap_and_set_painting(lower->volumes.back(), saved_painting);
+        lower->volumes.back()->restore_painting(saved_painting);
     }
 }
 

src/libslic3r/Model.cpp

@@ -1980,6 +1980,41 @@ void ModelVolume::reset_extra_facets()
     this->fuzzy_skin_facets.reset();
 }
 
+std::optional<TriangleSelector::SavedPainting> ModelVolume::save_painting() const
+{
+    if (is_any_painted() && is_model_part() && !mesh().empty()) {
+        TriangleSelector::SavedPainting sp;
+        sp.mesh      = mesh();
+        sp.supported = supported_facets.get_data();
+        sp.seam      = seam_facets.get_data();
+        sp.mmu       = mmu_segmentation_facets.get_data();
+        sp.fuzzy     = fuzzy_skin_facets.get_data();
+        return sp;
+    }
+
+    return {};
+}
+
+void ModelVolume::restore_painting(const std::optional<TriangleSelector::SavedPainting>& saved)
+{
+    if (!saved) {
+        return;
+    }
+
+    auto remap_one = [&](const TriangleSelector::TriangleSplittingData& src_data,
+                         FacetsAnnotation& target_facets) {
+        if (src_data.bitstream.empty())
+            return;
+        auto result = TriangleSelector::remap_painting(saved->mesh.its, src_data, mesh().its, Geometry::translation_transform(mesh().get_init_shift()));
+        if (!result.bitstream.empty())
+            target_facets.set_data(result);
+    };
+    remap_one(saved->supported, supported_facets);
+    remap_one(saved->seam,      seam_facets);
+    remap_one(saved->mmu,       mmu_segmentation_facets);
+    remap_one(saved->fuzzy,     fuzzy_skin_facets);
+}
+
 static void invalidate_translations(ModelObject* object, const ModelInstance* src_instance)
 {
     if (!object->origin_translation.isApprox(Vec3d::Zero()) && src_instance->get_offset().isApprox(Vec3d::Zero())) {

src/libslic3r/Model.hpp

@@ -881,20 +881,10 @@ public:
     // Save painting data before reset_extra_facets() discards it.
     // Used for replacing mesh without losing painting data.
     // Only for model parts (not modifiers/connectors).
-    std::optional<TriangleSelector::SavedPainting> save_painting() const
+    std::optional<TriangleSelector::SavedPainting> save_painting() const;
-    {
-        if (is_any_painted() && is_model_part() && !mesh().empty()) {
-            TriangleSelector::SavedPainting sp;
-            sp.mesh      = mesh();
-            sp.supported = supported_facets.get_data();
-            sp.seam      = seam_facets.get_data();
-            sp.mmu       = mmu_segmentation_facets.get_data();
-            sp.fuzzy     = fuzzy_skin_facets.get_data();
-            return sp;
-        }
     
-        return {};
+    // Remap painting data from previous saved source to this mesh
-    }
+    void restore_painting(const std::optional<TriangleSelector::SavedPainting>& saved);
 
     // BBS: quick access for volume extruders, 1 based
     mutable std::vector<int> mmuseg_extruders;