code: public static Vector3D_F64 constraint(TrifocalTensor tensor,
  										  Point2D_F64 p1, Point2D_F64 p2, Vector3D_F64 l3,
  										  Vector3D_F64 ret)
  	{
  		if( ret == null )
  			ret = new Vector3D_F64();
  
  		DMatrixRMaj sum = new DMatrixRMaj(3,3);
  
  		CommonOps_DDRM.add(p1.x,tensor.T1,sum,sum);
  		CommonOps_DDRM.add(p1.y,tensor.T2,sum,sum);
  		CommonOps_DDRM.add(tensor.T3,sum,sum);
  
  		DMatrixRMaj cross2 = GeometryMath_F64.crossMatrix(p2.x,p2.y,1,null);
  
  		DMatrixRMaj temp = new DMatrixRMaj(3,3);
  
  		CommonOps_DDRM.mult(cross2,sum,temp);
  		GeometryMath_F64.mult(temp, l3, ret);
  
  		return ret;
  	}
docs: <p>
  Trifocal tensor with point-point-line correspondence:<br>
  [p2]<sub>x</sub>(sum p1<sup>i</sup>*T<sub>i</sub>)*l3 = 0
  </p>
  
  @param tensor Trifocal tensor
  @param p1 A point in the first view.
  @param p2 A point in the second view.
  @param l3 A line in the third view.
  @return Result of applying the constraint.  With perfect inputs will be zero.