Robust Hollow-Out of Triangle Meshes with Signed Distance Field

• Main Authors: Hung-Hsien Chen, 陳弘憲
• Other Authors: 莊永裕
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/vd4mp6

碩士 === 國立臺灣大學 === 資訊網路與多媒體研究所 === 105 === Triangle mesh is widely used for representing 3D models. By stitching an amount of triangles, it can approximate the surface of an object. Theoretically, the more the triangles, the more accurate it would be. It is also the default input format for 3D printing. Triangle mesh only describes the surface of an object. For 3D printing, it is viewed as a solid object. However, in many circumstance, e.g. making lanterns, instruments or, as we would discuss later, piggy banks, an empty model is required. So we have to edit the original mesh. When the mesh is simple, one could manually hollow it out with CAD software. But for those more complicated models, it could be quite challenging and time-consuming. As a result, we developed a system that can automatically and robustly hollow out triangle meshes. Our program will first calculate Signed Distance Field (abbreviated as SDF) for the triangle mesh. SDF records the distance from points in 3D space to the surface of the model. The sign of the distance being positive or negative indicates the point is outside or inside the model, respectively. Then, we will apply a well-known algorithm, Marching Cubes, to regenerate the surface of the inner hole. And finally combine this inner model with the input mesh to get an empty model. In our experiments, as long as the input model follows the basic assumptions of SDF, our system can robustly generate corresponding hollow model.