/// <summary>
/// Initializes a new instance of the <see cref="PrimitiveSurface" /> class.
/// </summary>
/// <param name="faces">The faces.</param>
protected PrimitiveSurface(IEnumerable <PolygonalFace> faces)
{
Type = PrimitiveSurfaceType.Unknown;
Faces = faces.ToList();
foreach (var face in faces)
{
face.BelongsToPrimitive = this;
}
Area = Faces.Sum(f => f.Area);
Vertices = Faces.SelectMany(f => f.Vertices).Distinct().ToList();
}