Cleanup: Add check whether to remove an anonymous atttribute

Add a higher level check that can be used instead of checking whether
the attribute ID is anonymous and checking whether it has any strong
references.

3 files changed, 17 insertions, 11 deletions

diff --git a/source/blender/blenkernel/BKE_attribute_access.hh b/source/blender/blenkernel/BKE_attribute_access.hh
index ff2aebc7d10..4a1c29badb4 100644
--- a/source/blender/blenkernel/BKE_attribute_access.hh
+++ b/source/blender/blenkernel/BKE_attribute_access.hh
@@ -55,6 +55,7 @@ class AttributeIDRef {
   bool is_anonymous() const;
   StringRef name() const;
   const AnonymousAttributeID &anonymous_id() const;
+  bool should_be_kept() const;
 
   friend bool operator==(const AttributeIDRef &a, const AttributeIDRef &b);
   friend std::ostream &operator<<(std::ostream &stream, const AttributeIDRef &attribute_id);
@@ -438,6 +439,16 @@ inline const AnonymousAttributeID &AttributeIDRef::anonymous_id() const
   return *anonymous_id_;
 }
 
+/**
+ * \return True if the attribute should not be removed automatically as an optimization during
+ * processing or copying. Anonymous attributes can be removed when they no longer have any
+ * references.
+ */
+inline bool AttributeIDRef::should_be_kept() const
+{
+  return this->is_named() || BKE_anonymous_attribute_id_has_strong_references(anonymous_id_);
+}
+
 /** \} */
 
 /* -------------------------------------------------------------------- */
diff --git a/source/blender/blenkernel/intern/geometry_set.cc b/source/blender/blenkernel/intern/geometry_set.cc
index e439cc838e3..4753a9e0768 100644
--- a/source/blender/blenkernel/intern/geometry_set.cc
+++ b/source/blender/blenkernel/intern/geometry_set.cc
@@ -507,12 +507,11 @@ void GeometrySet::gather_attributes_for_propagation(
             return;
           }
         }
-        if (attribute_id.is_anonymous()) {
-          if (!BKE_anonymous_attribute_id_has_strong_references(&attribute_id.anonymous_id())) {
-            /* Don't propagate anonymous attributes that are not used anymore. */
-            return;
-          }
+
+        if (!attribute_id.should_be_kept()) {
+          return;
         }
+
         auto add_info = [&](AttributeKind *attribute_kind) {
           attribute_kind->domain = meta_data.domain;
           attribute_kind->data_type = meta_data.data_type;
diff --git a/source/blender/geometry/intern/mesh_to_curve_convert.cc b/source/blender/geometry/intern/mesh_to_curve_convert.cc
index 64b9fa5c01d..24f0b6308ba 100644
--- a/source/blender/geometry/intern/mesh_to_curve_convert.cc
+++ b/source/blender/geometry/intern/mesh_to_curve_convert.cc
@@ -78,12 +78,8 @@ static void copy_attributes_to_points(CurveEval &curve,
       continue;
     }
 
-    /* Don't copy anonymous attributes with no references anymore. */
-    if (attribute_id.is_anonymous()) {
-      const AnonymousAttributeID &anonymous_id = attribute_id.anonymous_id();
-      if (!BKE_anonymous_attribute_id_has_strong_references(&anonymous_id)) {
-        continue;
-      }
+    if (!attribute_id.should_be_kept()) {
+      continue;
     }
 
     const fn::GVArrayPtr mesh_attribute = mesh_component.attribute_try_get_for_read(