public class Plane
{
public Triangle T1;
public Triangle T2;
    
public Plane(double x0, double y0, double z0,
	     double x1, double y1, double z1,
	     double x2, double y2, double z2,
	     double x3, double y3, double z3)
    {
	T1 = new Triangle(x0, y0, z0, x1, y1, z1, x2, y2, z2);
	T2 = new Triangle(x0, y0, z0, x2, y2, z2, x3, y3, z3);
    }
    
public Plane(Triangle t1, Triangle t2)
    {
	T1 = t1;
	T2 = t2;
    }
    
public Plane rot(m3x3 M)
    {
	return (new Plane(T1.rot(M), T2.rot(M)));
    }
    
public Plane tran(v3x1 off)
    {	
	return (new Plane(new Triangle(T1, off),
			  new Triangle(T2, off)));
    }
}