From b1f151e598425dd178f554304bb1b2f8b5e50b2f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=A9bastien=20Loriot?= <sebastien.loriot@cgal.org>
Date: Thu, 7 Aug 2025 18:19:02 +0200
Subject: [PATCH 1/3] use only one specialization using FT

cannot get the specialization as an object inherits from Lazy
---
 Filtered_kernel/include/CGAL/Lazy.h | 26 +++++++++++---------------
 1 file changed, 11 insertions(+), 15 deletions(-)

diff --git a/Filtered_kernel/include/CGAL/Lazy.h b/Filtered_kernel/include/CGAL/Lazy.h
index 5d7b22ec37b..9b4041793c1 100644
--- a/Filtered_kernel/include/CGAL/Lazy.h
+++ b/Filtered_kernel/include/CGAL/Lazy.h
@@ -112,23 +112,19 @@ template<class T>inline std::enable_if_t<std::is_empty<T>::value, int> depth(T){
 
 namespace internal{
 
-  template <typename AT, typename ET, typename E2A>
-  struct Evaluate<Lazy<AT, ET, E2A>>
+template <typename ET>
+struct Evaluate<Lazy_exact_nt<ET>>
+{
+  template <typename AT, typename ET2, typename E2A>
+  void operator()(const Lazy<AT, ET2, E2A>& l)
   {
-      void operator()(const Lazy<AT, ET, E2A>& l)
-      {
-          exact(l);
-      }
+    exact(l);
+  }
+  void operator()(const Lazy_exact_nt<ET>& l)
+  {
+    exact(l);
+  }
 };
-
-  template <typename ET>
-  struct Evaluate<Lazy_exact_nt<ET>>
-  {
-      void operator()(const Lazy_exact_nt<ET>& l)
-      {
-          exact(l);
-      }
-  };
 } // internal namespace
 
 // For an iterator, exact/approx applies to the objects it points to

From fdd7c17ec1217ec9d14ec1189d5a509176ef548e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=A9bastien=20Loriot?= <sebastien.loriot@cgal.org>
Date: Thu, 7 Aug 2025 18:20:20 +0200
Subject: [PATCH 2/3] avoid large dag in centroid

---
 .../include/CGAL/Polygon_mesh_processing/measure.h            | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/measure.h b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/measure.h
index 42492891ef0..43ee6eb534f 100644
--- a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/measure.h
+++ b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/measure.h
@@ -893,6 +893,8 @@ centroid(const TriangleMesh& tmesh,
   Scale scale = k.construct_scaled_vector_3_object();
   Sum sum = k.construct_sum_of_vectors_3_object();
 
+  ::CGAL::internal::Evaluate<FT> evaluate;
+
   for(face_descriptor fd : faces(tmesh))
   {
     const Point_3_ref p = get(vpm, target(halfedge(fd, tmesh), tmesh));
@@ -903,6 +905,7 @@ centroid(const TriangleMesh& tmesh,
              vr = vector(ORIGIN, r);
     Vector_3 n = normal(p, q, r);
     volume += (scalar_product(n,vp))/FT(6);
+    evaluate(volume);
     n = scale(n, FT(1)/FT(24));
 
     Vector_3 v2 = sum(vp, vq);
@@ -913,6 +916,7 @@ centroid(const TriangleMesh& tmesh,
     v3 = sum(v3, Vector_3(square(v2.x()), square(v2.y()), square(v2.z())));
 
     centroid = sum(centroid, Vector_3(n.x() * v3.x(), n.y() * v3.y(), n.z() * v3.z()));
+    evaluate(centroid);
   }
 
   centroid = scale(centroid, FT(1)/(FT(2)*volume));

From 29e6836e9c9e6df9796b77e3672743f3f5a1f561 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=A9bastien=20Loriot?= <sebastien.loriot@cgal.org>
Date: Thu, 7 Aug 2025 18:44:34 +0200
Subject: [PATCH 3/3] we need to support all types of objects

---
 Number_types/include/CGAL/utils_classes.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Number_types/include/CGAL/utils_classes.h b/Number_types/include/CGAL/utils_classes.h
index 1b4eb95ce89..f7052a8c59a 100644
--- a/Number_types/include/CGAL/utils_classes.h
+++ b/Number_types/include/CGAL/utils_classes.h
@@ -272,7 +272,8 @@ namespace internal
 template <class NT>
 struct Evaluate
 {
-  void operator()(const NT&)
+  template <class T>
+  void operator()(const T&)
   {}
 };
 } // internal namespace