180 / 2023-08-31 20:17:53

Efficient Voxel Models Construction of Ore Bodies Using the Improved Winding Number Algorithm and CUDA Parallel Computing

3D modeling,ore body model,voxel models,Winding number algorithm,CUDA

3D visual modeling is one part of important application in the research area of computer vision, which is of great significance for the realistic demand, such as geological data analysis of mining, dynamic simulation of mining and so on. At present, there are many 3D ore body modeling software in China and Abroad, such as 3DMine, Dmine, Autodesk and ansy, etc. This research realizes the construction and multi-platform application of 3D ore body model through open-source software. In the application domain of mineral content estimation, the ore block model is the main method to realize the construction of three-dimensional voxel models. The basic problem of this modeling to be solved is the "Point in Polygon" in three-dimensional space, which has some relatively perfect solution in two-dimensional space, but it is still complicated to realize in three-dimensional space. For this question, an effective method is Winding number algorithm in 3D, but when calculating each addend in the accumulation process, additional means are needed, such as artificially setting the observation point to restrict the positive and negative of this value so as to obtain the correct calculation result by the direction of the observation point looking towards the geometry, which is not conducive to the automation of the modeling process. Therefore, in order to solve this problem, this paper proposed the improved Winding number algorithm in 3D with triangle network coding (Tri-Coding, namely the WNTC algorithm. The proposed WNTC algorithm uses the classic method of Delaunay triangulation network to build a stratum model, and encodes it by constraining the index order of each vertex of the triangular plane unit. In addition, programming of CUDA is used to improve the speed of 3D voxel models construction by the proposed WNTC algorithm, calculating the correct signed winding number by the normal vector of the triangle faces. By comparing the voxel modeling effect of Ray casting method and WNTC algorithm, the results show that, WNTC algorithm can improve the phenomenon of voxel loss in the middle of voxelization modeling compared with Ray casting method, and is more effective and has higher automation performance in 3D ore body modeling. In the comparison of computing efficiency between CPU and GPU, the average computing time of CUDA program on GPU for the same computing step is only 0.04% of the computing time on CPU. The speed of voxel model construction is greatly improved, and it is also less affected by the complexity of the stratum model.