An Improved Fast Algorithm for Calculating the Gradient of Data Field
Jia Zhong, Ziming Zou · 2017
It is an important part of extracting the border in volume visualization for computing gradient feature of spatial data accurately and rapidly. The traditional method of volume visualization is to resample the data of model or observation distributing on non-uniform grids of three-dimensional Euclidean space by trilinear interpolation to uniform grids, then calculate gradient features of all grid vertex data. This paper designs an improved algorithm, based on properties of equal partial derivatives along axis after data linear interpolation, it removes a large number of repetitive calculations and redundant storage of partial derivatives, in traditional method. Finally, this paper verifies the algorithm validity with visualization experiments using the MHD simulation data to extract the magnetopause.