/// <summary>
/// Returns the unitized sum of halfedge normals around the vertex.
/// </summary>
/// <returns></returns>
public static Vec3d GetNormal <V, E, F>(this IHeVertex <V, E, F> vertex, Func <V, Vec3d> getPosition)
where V : IHeVertex <V, E, F>
where E : IHalfedge <V, E, F>
where F : IHeFace <V, E, F>
{
return(vertex.OutgoingHalfedges.Where(he => !he.IsHole).Sum(he => he.GetNormal(getPosition)).Direction);
}
/// <summary>
/// Returns the unitized sum of halfedge normals around the vertex.
/// </summary>
/// <returns></returns>
public static Vec3d GetNormal <V, E, F>(this IHeVertex <V, E, F> vertex)
where V : IHeVertex <V, E, F>, IVertex3d
where E : IHalfedge <V, E, F>
where F : IHeFace <V, E, F>
{
return(GetNormal(vertex, IVertex3dStatic <V> .GetPosition));
}
/// <summary>
/// Returns the unitized sum of halfedge normals around the vertex.
/// </summary>
/// <returns></returns>
public static Vec3d GetNormal <V, E, F>(this IHeVertex <V, E, F> vertex, Func <E, Vec3d> getNormal)
where V : IHeVertex <V, E, F>
where E : IHalfedge <V, E, F>
where F : IHeFace <V, E, F>
{
Vec3d result = vertex.OutgoingHalfedges.Sum(getNormal);
result.Unitize();
return(result);
}
