摘要
目的网格重建和编辑会产生几何特征缺失的模型,填补这些空洞具有重要的意义。为了克服复杂曲面修补中网格融合难以配准的问题,提出了环驱动球坐标结合基于曲率及法向ICP(iterative closest point)迭代配准的网格修补方法。方法首先用户查找合适的源网格面片放入空洞处周围;然后对目标网格空洞环建立B样条曲线,将带修补网格包边界置于B样条曲线上,构架环驱动球坐标,将源网格变形初步配准目标网格空洞周围领域;最后使用Laplacian光顺并基于网格曲率及法向进行ICP迭代配准,使源网格与目标网格光滑拼接融合。结果该方法能够有效修补网格空洞缺失的细节特征,并且拼接处光滑连续。结论环驱动球坐标配准避免了网格变形的包围网格笼子构造,再通过ICP迭代精确配准网格,和以往的网格修补方法相比,该方法能够很好地修补网格空洞处细节特征。
Objective Missing geometry appears during mesh reconstruction and editing; completing the holes is thus important. To complete the holes of a complex surface effectively,mesh completion based on loop-driven spherical coordinates and iterative closest point( ICP) registration with curvature and normal is presented. Method First,the user searches for a similar mesh patch and places it around the hole of the mesh. Second,the B-spline curve is utilized to fit the hole boundary of the target. The boundary loop of the source mesh is located on the B-spline. Loop-driven spherical coordinates,which map and deform the source mesh patch to match the target mesh,are then constructed. Finally,Laplacian smoothing and the ICP algorithm with curvature and normal are applied to complete the mesh completion. Two mesh parts are merged smoothly. Result Experimental results reveal the proposed algorithm's ability to retrieve a missing feature effectively and smoothly. Conclusion The loop-driven spherical coordinates prevent the application of cage meshes to deformation,and the ICP iteration can complete the registration effectively. Compared with earlier approaches,the proposed algorithm can retrieve a missing feature effectively.
引文
[1]Liepa P.Filling holes in meshes[C]//Eurographics/ACM SIGGRAPH Symposium on Geometry Processing.Aachen,Germany:ACM Press,2003:200-205.
[2]Wang J,Oliveira M M.Filling holes on locally smooth surfaces reconstructed from point clouds[J].Image and Vision Computing,2007,25(1):103-113.
[3]Branch J,Prieto F,Boulanger P.A hole-filling algorithm for triangular meshes using local radial basis function[C]//Symposium on 3D Data Processing,Visualization and Transmission.Chapel Hill,USA:IEEE Computer Society Press,2006:727-734.
[4]Chen C Y,Cheng K Y.A sharpness-dependent filter for recovering sharp features in repaired 3D mesh models[J].IEEE Transactions on Visualization and Computer Graphics,2008,14(1):200-212.
[5]Sharf A,Alexa M,Cohen-Or D.Context-based surface completion[J].ACM Transactions on Graphics,2004,23(3):878-887.
[6]Harary G,Tal A,Grinspun E.Context-based coherent surface completion[J].ACM Transactions on Graphics,2014,33(1):#5(1-12).
[7]Floater M S.Mean value coordinates[J].Computer Aided Geometric Design,2003,20(1):19-27.
[8]Floater M S,Kos G,Reimers M.Mean value coordinates in 3D[J].Computer Aided Geometric Design,2005,22(7):623-631.
[9]Langer T,Belyaev A,Seidel H P.Spherical barycentric coordinates[C]//Eurographics Symposium on Geometry Processing.New York:ACM Press,2006:81-88.
[10]Besl P J,Mckay N D.A Method for registration of 3-D shapes[J].IEEE Transactions on Pattern Analysis and Machine Intelligence,1992,14(2):239-256.
[11]Du S Y,Zheng N N,Ying S H.Affine iterative closest point algorithm for point set registration[J].Pattern Recognition Letters,2010,31(9):791-799.
[12]Xie Z X,Xu S,Li X Y.A high accuracy method for fine registration of overlapping point clouds[J].Image and Vision Computing,2010,28(4):563-570.
[13]Ju T,Schaefer S,Warren J.Mean value coordinates for closed triangular meshes[C]//Proceedings of Computer Graphics Proceedings,Annual Conference Series,ACM SIGGRAPH.New York:ACM Press,2005:561-566.
[14]Sorkine O,Lipman Y,Cohen-or D,et al.Laplacian surface editing[C]//Proceeding of Eurographics/ACM SIGGRAPH Symposium on Geometry Processing.Nice,France:ACM Press,2004:175-184
[15]Arun K S,Huang T S,Blostein S.Least squares Fitting of Two3-D Point Sets[J].IEEE Transactions on Pattern Analysis and Machine Intelligence,1987,9(5):698-700.
[16]Harary G,Tal A,Grinspun E.Feature-preserving surface completion using four points[J].Computer Graphics Forum,2014,33(5):45-54.