vcl::HasFaces Concept Reference

HasFaces concepts is satisfied when at least one of its template types is (or inherits from) a vcl::mesh::FaceContainer. It can be used both to check if a Mesh has faces, or if in a list of types there is a FaceContainer. More...

#include <vclib/concepts/mesh/containers/face_container.h>

Concept definition

template<typename... Args>
concept vcl::HasFaces =  (mesh::HasFaceContainer<Args> || ...)

Detailed Description

HasFaces concepts is satisfied when at least one of its template types is (or inherits from) a vcl::mesh::FaceContainer. It can be used both to check if a Mesh has faces, or if in a list of types there is a FaceContainer.

In the following example, a MyMesh type can be instantiated only if one of its template Args is a FaceContainer:

template <typename... Args> requires HasFaces<Args...>
class MyMesh {
    // ...
};
 
// ...
 
MyMesh<vcl::VertexContainer<MyVertex>> m1; // not ok
MyMesh<vcl::FaceContainer<MyFace>> m2; // ok
MyMesh<vcl::VertexContainer<MyVertex>, vcl::FaceContainer<MyFace>> m3; // ok

To check if a type has (inherits from) FaceContainer:

if constexpr (vcl::HasFaces<MyMeshType>) {
    // ...
}

Note

This concept does not check if a Mesh is a valid FaceMesh. To do that, use the vcl::FaceMeshConcept.