The Research On Virtual Repair Method For Bronze Sights And 3D Effect Display

When bronze cultural relic are unearthed,they tend to have varying degrees and shape of damage.In view of the laborious and time-consuming secondary repairs caused by manual repair,the use of computer-assisted repair has become an important measure to improve the efficiency and effectiveness of bronze artifact restorations.Because of the different types of holes in broken bronzes and the problems caused by corrosion and other reasons that lead to structural difficulties and difficult repairs,the following research was conducted on virtual repair of bronze holes based on computer technology:(1)According to the characteristics of bronze holes.Based on whether the boundary of the hole is closed or not,it is divided into a fully closed hole and an open hole,which lays a foundation for the subsequent classification and repair.(2)A method utilized to virtual repair the complex boundary hole is proposed based on the backtracking bidirectional wavefront method Firstly,the bronze cloud data are deal with triangular mesh and the boundary of hole extracted in mesh.Then,the boundary of the pseudo-hole are removed by comparing the curvature fluctuation range of the boundary point set.Secondly,the point of backtracking result is the initial point set and combine the method of vector cross product to classify the concave and convex points,which,respectively,are operated by positive and negative wavefront method before adding a new set of points until the completion.Then the least squares method is used to fit the surface to smooth the added point set and then the final patching result is obtained.The hole-filling meshes are obtained by our method interpolate the shape and have consistent mesh distribution and smooth transition with the surrounding meshes and effectively repair the cloud holes of complex boundary.(3)A novel method of virtual repair the point cloud opening-holes is proposed based on modified curve contraction flow,which aim to improve the effect of existing means.Firstly,on the basis of calculating the surface normal vector and tangent vector of the hole boundary point,the whole boundary is formed according to the feature line.Secondly,the cross-point of each boundary point is obtained by the intersection of the vertical plane of the tangent vector and the boundary,and a cross-vector is formed with the corresponding boundary point;the growth direction of the boundary point is calculated by using the weighted sum of the inward vector and the cross-vector,and the growth step is determined according to the density of the original point cloud so as to be repaired.Finally,Laplace smoothing algorithm is utilized to smooth and uniform mesh for obtaining final repairing result.The experimental results show that this method can repair opening-holes effectively.(4)Designed and developed a bronze 3D effect display website.The three-dimensional display can be quickly and efficiently achieved through mouse control,including panning,zooming,rotation and calculating geometric properties by means of human-computer interactive.The website is simple to operate and requires no other plugins,which can provide reliable technical support for subsequent digital museums.