A method called the switch-back technique allows us to drastically reduce computation time of occlusion-processing based on the polygon-by-polygon silhouette light-shielding. It is also reported that further reduction of computation time can be achieved by splitting an object to some sub-models along with depth direction. However, computational cost for numerical propagation between the sub-models increases with increasing the number of sub-models. As a result, there is an optimum number of sub-models. In this paper, we propose a technique to predict the optimum number of sub-models by estimating the total computational complexity of the switch-back technique with object splitting.
High-definition computer holography based on the polygon-based method commonly uses the silhouette method to shield light behind objects for hidden surface removal. However, the light-shielding is not perfect and causes leakage light passing through many gaps between silhouette-shaped masks. Although we have proposed the principle of more rigorous technique to remove the leakage light, the technique has never been applied to the actual high-definition computer holography because of its long computation time. We propose some techniques to reduce the computation time and apply the rigorous technique to high-definition computer holography. A CGH created by the proposed method is demonstrated.