Biography
Enrollment Date: 2012
Graduation Date：2015
Degree：M.S.
Defense Date：2015.06.02
Advisors：Yangdong Deng
Department：Institute of Microelectronics，Tsinghua University
Title of Dissertation/Thesis：Computer-aided Shadow Art and Automatic LEGO Construction of Shadow Sculptures
Abstract:
With the rapid development of computer graphics, audio-visual art has come to its full bloom. Shadow art can create amazing visual effects and is often combined with interior design or architectural decoration. The LEGO bricks, because of their infinite possibilities in 3D modeling, are called “magic plastic bricks”. This thesis aims to design algorithms for generating shadow art and building their LEGO models automatically, which can shorten the time and reduce the costs, thus are meaningful in both the aesthetic and practical sense. By analyzing the graphical law of the creation process of shadow art, this thesis presents a method of computer-generated shadow art modeling based on Shape-from-silhouette (SFS). Experiments show that the 3D models reconstructed with this method could project different shadows in two perpendicular directions. Secondly, this thesis explores the method of automatically transforming the shadow art models to 3D physical models using LEGO bricks. For any input 3D model, the automatic LEGO construction algorithm could output the bricks layout of each layer and provide users with concise visual building instructions, thus efficiency could be improved compared to a traditional trial-and-error way. In this paper, a delayed graph construction technique and a partition based top-down layout optimization flow are proposed, which could reduce the search space and improve the rate of convergence. The experiments show that compared with the best results in the literature, our LEGO algorithm has advantages in efficiency when dealing with high-resolution models. It decreased the total timing by 29% to 49% while at the same time ensuring the modeling quality.The main contribution of this thesis is that we put forward an automatic designing process of shadows art and LEGO construction for shadow sculptures. The generated shadow sculptures have quite good visual effects. Besides, the presented automatic LEGO construction algorithm has obvious efficiency advantage in processing large high-resolution models.