A depiction system for generating a real time correlated depiction of movements of a surgical tool for uses in minimally invasive surgery is described. In an embodiment the system includes a computer system, 3D surface data generation means and position data generation means for obtaining real time spatial position data of at least a part of the surgical tool. The 3D surface data generation means or the position data generation is adapted for providing surface position data of at least the target area. The computer system is programmed for determining depiction data representing a depiction of the real time relative spatial position(s) of the surgical tool onto at least a portion of the surface contour of the surface section of the minimally invasive surgery cavity.