fix(Facets): add more api around opposite facet

Author: BotellaA

include/geode/mesh/core/detail/facet_storage.hpp

@@ -43,14 +43,22 @@ namespace geode
             static constexpr auto ATTRIBUTE_NAME = "facet_vertices";
             friend class bitsery::Access;
 
+        public:
+            [[nodiscard]] bool is_opposite(
+                index_t facet_id, const VertexContainer& vertices ) const
+            {
+                const OrientedVertexCycle other_oriented_cycle{ vertices };
+                const OrientedVertexCycle oriented_cycle{ vertices_->value(
+                    facet_id ) };
+                return oriented_cycle.is_opposite( other_oriented_cycle );
+            }
+
         protected:
             FacetStorage()
-                : counter_(
-                      facet_attribute_manager_
+                : counter_( facet_attribute_manager_
                           .template find_or_create_attribute< VariableAttribute,
                               index_t >( "counter", 1u, { false, false } ) ),
-                  vertices_(
-                      facet_attribute_manager_
+                  vertices_( facet_attribute_manager_
                           .template find_or_create_attribute< VariableAttribute,
                               VertexContainer >( attribute_name(),
                               VertexContainer(),

include/geode/mesh/core/solid_edges.hpp

@@ -76,6 +76,9 @@ namespace geode
         [[nodiscard]] std::optional< index_t > edge_from_vertices(
             const std::array< index_t, 2 >& vertices ) const;
 
+        [[nodiscard]] bool is_opposite(
+            index_t edge_id, const std::array< index_t, 2 >& vertices ) const;
+
         /*!
          * Access to the manager of attributes associated with edges.
          */

include/geode/mesh/core/solid_facets.hpp

@@ -70,6 +70,9 @@ namespace geode
         [[nodiscard]] std::optional< index_t > facet_from_vertices(
             const PolyhedronFacetVertices& vertices ) const;
 
+        [[nodiscard]] bool is_opposite(
+            index_t facet_id, const PolyhedronFacetVertices& vertices ) const;
+
         /*!
          * Access to the manager of attributes associated with facets.
          */

include/geode/mesh/core/surface_edges.hpp

@@ -74,6 +74,9 @@ namespace geode
         [[nodiscard]] std::optional< index_t > edge_from_vertices(
             const std::array< index_t, 2 >& vertices ) const;
 
+        [[nodiscard]] bool is_opposite(
+            index_t edge_id, const std::array< index_t, 2 >& vertices ) const;
+
         /*!
          * Access to the manager of attributes associated with edges.
          */

src/geode/mesh/core/solid_edges.cpp

@@ -96,9 +96,7 @@ namespace geode
     }
 
     template < index_t dimension >
-    SolidEdges< dimension >::SolidEdges()
-    {
-    }
+    SolidEdges< dimension >::SolidEdges() = default;
 
     template < index_t dimension >
     SolidEdges< dimension >::~SolidEdges() = default;
@@ -132,6 +130,14 @@ namespace geode
         return impl_->find_edge( vertices );
     }
 
+    template < index_t dimension >
+    bool SolidEdges< dimension >::is_opposite(
+        index_t edge_id, const std::array< index_t, 2 >& vertices ) const
+    {
+        check_edge_id( *this, edge_id );
+        return impl_->is_opposite( edge_id, vertices );
+    }
+
     template < index_t dimension >
     void SolidEdges< dimension >::update_edge_vertices(
         absl::Span< const index_t > old2new, SolidEdgesKey )

src/geode/mesh/core/solid_facets.cpp

@@ -165,9 +165,7 @@ namespace geode
     }
 
     template < index_t dimension >
-    SolidFacets< dimension >::SolidFacets()
-    {
-    }
+    SolidFacets< dimension >::SolidFacets() = default;
 
     template < index_t dimension >
     SolidFacets< dimension >::~SolidFacets() = default;
@@ -201,6 +199,14 @@ namespace geode
         return impl_->find_facet( vertices );
     }
 
+    template < index_t dimension >
+    bool SolidFacets< dimension >::is_opposite(
+        index_t facet_id, const PolyhedronFacetVertices& vertices ) const
+    {
+        check_facet_id( *this, facet_id );
+        return impl_->is_opposite( facet_id, vertices );
+    }
+
     template < index_t dimension >
     std::vector< index_t > SolidFacets< dimension >::update_facet_vertices(
         absl::Span< const index_t > old2new, SolidFacetsKey )

src/geode/mesh/core/surface_edges.cpp

@@ -90,9 +90,7 @@ namespace geode
     };
 
     template < index_t dimension >
-    SurfaceEdges< dimension >::SurfaceEdges()
-    {
-    }
+    SurfaceEdges< dimension >::SurfaceEdges() = default;
 
     template < index_t dimension >
     SurfaceEdges< dimension >::SurfaceEdges(
@@ -185,6 +183,14 @@ namespace geode
         return impl_->find_edge( vertices );
     }
 
+    template < index_t dimension >
+    bool SurfaceEdges< dimension >::is_opposite(
+        index_t edge_id, const std::array< index_t, 2 >& vertices ) const
+    {
+        check_edge_id( *this, edge_id );
+        return impl_->is_opposite( edge_id, vertices );
+    }
+
     template < index_t dimension >
     AttributeManager& SurfaceEdges< dimension >::edge_attribute_manager() const
     {