The Feature-based Visualization Based On Topological Analysis Of 3D Scalar Fields

In computer graphics, the visualization of computer graphics always has an important application in 3D scalar fields. For large and complex flow data ,whether for science research or economic requirement, Feature-based Visualization all become an activity aspect for research, and the topological simplification of 3D scalar fields is always the focus in this domain, and it is becoming a favorite focus.Feature-based Visualization is a new visualization method, which is advanced on 1990s, and developing quickly. This kind of method, which is selectable, can filter outlying data to decrease the information to be disposed and even gain the quantificational description of the extracted feature, according to visualize those meaning parts in the field. Feature is the main task of method Feature-based Visualization and it is the first-line step for feature tracking and event detecting. Its target is measurating and describing the feature of the dataset. And it can be divided into image-based feature extraction, topology-based feature extraction.Water mass analysis is always a important thesis on the ocean research. Finding a method based on religious theory, which can depart the water mass externally,accurately, automatically and effectively, is always a problem needed to explore.This paper addresses introduction of feature-based visualization technology into the research on physical oceanography; For large and complex flow data such as ocean flow field, it's nearly impossible to visualize the whole information it contains. This paper introduces a topological simplification of 3D scalar fields for extracting water mass ,and realizes the feature-based visualization. By constructing Morse-Smale complex over the important subregions to depart the water mass automatically, and proceeding by repeatedly remove a pair of critical points from the complex to realize the combination of the initial water massm,this method is based on the morse theory. This method is based on visualization technology and the Morse theory that is based on topology theory. This new method has religious academic background, and it can gain the boundaries of water masses externally, accurately and automatically. By getting rid of the unavoidable random, its result is more believable.