How to make a symmetry?

I want to make a symmetry, so I made :

scale = new Vector3f(-1.0f,1.0f,1.0f);

The transformation returns a correct symmetry except that now, the normals are inverted. Is anyone knows a way to make a symmetry without normals inversion.


Maybe using the Node.setNormalsMode() method would work…

Anybody knows is there functions using symmetry points or planes in JME?