Research And Implementation Of Flattening Method For 3D Surface Pattern For Cultural Relics

Traditional patterns have rich cultural connotations and are widely used in cultural relics.Patterns are carried on different cultural carriers.Since the surface of cultural relics is composed of irregular curved surfaces,the patterns on the surface are deformed to a certain extent.We obtain traditional patterns with more complete geometry and richer meanings is significant research.In this paper,a model segmentation method based on surface multi-features and a boundary-first conformal parameterization method for non-target texture identification are proposed to ensure the true flattening of 3D surface patterns of cultural relics.The development of the flattening system for three-dimensional surface patterns of cultural relics is conducive to the flattening of patterns,and provides a reconstruction tool for the Chinese cultural material library.The main work and innovations of this paper include:(1)According to the configuration characteristics of cultural relic models and the requirement of topological homeomorphism in the disk structure,this paper combines multiple surface features to segment the model.Firstly,the symmetry axis of the model is obtained for attitude correction,then a local coordinate system is constructed to obtain the normal phase estimated angle feature of the vertex,and the seed area is obtained by combining the average curvature feature of the vertex,and all the areas to be separated are obtained by the method of area growth.The isolated area is deleted by the method of priority search,and finally the model is segmented with all the areas to be separated.Experiments show that the segmentation method can improve the smoothness of the model boundary and the consistency of the texture,which is beneficial to the subsequent mesh parameterization work.(2)Aiming at the problem of a single boundary of the model,this paper places marked points on the model,connects the marked points in turn to form the shortest path as a combined line,and uses the combined line to form a virtual ring,and combines multiple boundaries into a single boundary at the connection between the virtual ring and boundary.For the problem of texture details at the boundary,the smoothness of the boundary is ensured by sampling the non-target texture identification and remeshing the boundary triangle.The parameterized boundary vertex coordinates are calculated according to the Cherrier scaling factor formula,and constraints can be imposed on the angle and side length to control the boundary shape,and then the internal vertex coordinates are solved according to the Laplace-Poisson and Laplace-Newman equations.Finally,the texture mapping transformation is applied to the parameterized 2D mesh model to obtain a 2D image of the surface pattern.Experimental comparisons are carried out on the segmented model data,and the method outperforms other similar parameterization methods.(3)According to the proposed business requirements and user requirements,a three-dimensional surface pattern flattening system for cultural relics is designed and implemented.The segmentation and parameterization algorithms proposed in this paper are integrated into the system and provide functions for model rendering and visual interaction.Provides custom setting of normal angle parameters and boundary angle parameters to complete model segmentation and parameterization.It serves as a platform for users to independently complete the flattening of the surface patterns of cultural relics.