Cage, which is adopted as the proxy geometry, plays an important role in processing high-precision and complex models in computer animation and geometric modeling. Currently, cage generation algorithms are heavily dependent on representation and complexity of the shape, which could not be applied to various models universally. To decouple the cage generation from the representation and complexity of the shape, the paper proposes a cage generation algorithm based on visual hull in computer vision. The algorithm can generate tight and coarse cage by inverse simulation of visual hull construction procedure. The results demonstrate usability and efficiency of the proposed algorithm.