From 5aed18e8c0fdbf6e79d899c3a79ad685dc28b7c4 Mon Sep 17 00:00:00 2001
From: benoitTHEBAULT <benoit.thebault@geode-solutions.com>
Date: Thu, 12 Dec 2024 10:28:48 +0100
Subject: [PATCH] feat(Geometry): adding new tetrahedron quality metric (volume
 to edge ratio).

---
 src/geode/geometry/quality.cpp     | 23 +++++++++++++++++++++++
 src/geode/mesh/core/solid_mesh.cpp |  8 +++-----
 2 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/src/geode/geometry/quality.cpp b/src/geode/geometry/quality.cpp
index 69ffc7876..2c4ca524d 100644
--- a/src/geode/geometry/quality.cpp
+++ b/src/geode/geometry/quality.cpp
@@ -28,6 +28,7 @@
 #include <limits>
 
 #include <geode/geometry/basic_objects/tetrahedron.hpp>
+#include <geode/geometry/mensuration.hpp>
 #include <geode/geometry/vector.hpp>
 
 namespace geode
@@ -64,4 +65,26 @@ namespace geode
             constant * longest_edge_length * total_area2 / absolute_det;
         return aspect_ratio;
     }
+
+    double tetrahedron_volume_to_edge_ratio( const Tetrahedron& tetra )
+    {
+        const auto signed_volume = geode::tetrahedron_signed_volume( tetra );
+        double sq_len{ 0 };
+        const auto& vertices = tetra.vertices();
+        for( const auto v0 : geode::LRange{ 3 } )
+        {
+            const auto& point0 = vertices[v0].get();
+            for( const auto v1 : geode::LRange{ v0, 4 } )
+            {
+                const auto& point1 = vertices[v1].get();
+                for( const auto d : geode::LRange{ 3 } )
+                {
+                    const auto diff = point0.value( d ) - point1.value( d );
+                    sq_len += diff * diff;
+                }
+            }
+        }
+        const auto l_rms = std::sqrt( sq_len / 6 );
+        return 6 * std::sqrt( 2 ) * signed_volume / ( l_rms * l_rms * l_rms );
+    }
 } // namespace geode
diff --git a/src/geode/mesh/core/solid_mesh.cpp b/src/geode/mesh/core/solid_mesh.cpp
index e4f4b7fdd..2b17e6c16 100644
--- a/src/geode/mesh/core/solid_mesh.cpp
+++ b/src/geode/mesh/core/solid_mesh.cpp
@@ -412,13 +412,11 @@ namespace geode
 
     public:
         explicit Impl( SolidMesh& solid )
-            : polyhedron_around_vertex_(
-                  solid.vertex_attribute_manager()
+            : polyhedron_around_vertex_( solid.vertex_attribute_manager()
                       .template find_or_create_attribute< VariableAttribute,
                           PolyhedronVertex >(
                           "polyhedron_around_vertex", PolyhedronVertex{} ) ),
-              polyhedra_around_vertex_(
-                  solid.vertex_attribute_manager()
+              polyhedra_around_vertex_( solid.vertex_attribute_manager()
                       .template find_or_create_attribute< VariableAttribute,
                           CachedPolyhedra >(
                           POLYHEDRA_AROUND_VERTEX_NAME, CachedPolyhedra{} ) )
@@ -1260,7 +1258,7 @@ namespace geode
             {
                 facet_vertices.push_back(
                     vertices[polyhedron_facet_vertex_id( { facet, v } )
-                                 .vertex_id] );
+                            .vertex_id] );
             }
         }
         return facets_vertices;