| Technique of generating realistic graphics especially for those irregular objects is one of the most challenging, active subjects in computer graphics. Moreover, generating the realistic graphics of the explosion of virtual object is more challenging. Based on the subject named "3D Real-time Image Generation and Display", which is one of the vital research subjects of the nine fifth-year plan established by the committee of national defense science and industry, the paper firstly researches on modeling theories and methods of virtual shell explosion, then discusses the data structure for modeling on virtual shell explosion roundly, and advances the general methods and detailed implementations of simulating on shell explosion process. The primary work and remarks of the paper are:(1) The paper introduces the correlations among nodes of half-edge data structure in detail, and takes an emphasis on discussing the correlations between half-edge node and other nodes. It presents the concept called stochastic half-edge data structure, discusses the stochastic attribute and its idiographic signification in a half-edge node.(2) Based on the object prototype represented by half-edge data structure, the paper presents a method to construct fragments in explosion, which is called random-classification construction method. This method is especially satisfying when applied on two simple model of fragment, namely equality probability breaking model and uniformity prefabrication fragment model. And the paper presents the concepts about conjunctive relation and equivalent relation among facets. The paper analyses the explosion mechanism of objects and presents some reasonable assumptions about explosion, then several properties about fragment construction can be deduced.(3) The paper firstly brings forward the concepts of concealed fragment, apparent fragment. It also advances two fragment generation methods: facet equivalence method and facet set enclosing method, and realizes three practical algorithms: the first one is to make a virtual entity particulate, the second is facet equivalence algorithm, the last is seed facet set enclosing algorithm. The paper analyzes and compares the last two methods and related algorithms, researches on applying the two methods to the break process of a virtual entity.(4) The paper proposes a new data structure especially for representing three-dimension objects called half-facet data structure, which provides a firm foundation for further research on modeling of irregular objects. In this paper, the connections among all nodes are given and fourmethods of transforming half-edge data structure into half-face data structure are presented. These methods are facet cutting method, particulates contracting method, facets enveloping method and enveloping objects method. At the same time half-facet data structure can be transformed using the dual facet annihilating method.(5) The paper presents a new random-classification construction method based on half-facet data structure. The application verifies the feasibility of the methods generating fragments, 3D characteristic of fragments and the stochastic characteristic of fragments.(6) The paper advances a data structure that is suitable for the simulation of bomb explosion. The data structure is called stochastic half-edge data structure with motion characteristics. By considering the mechanics and the correlative characteristics of the explosion, the paper constructs three models corresponding to the three phases during an explosion. They are expanding model of the bomb body, bursting model of the bomb body and motion model of the fragments. According to the models, the paper gives a detailed algorithm for the whole process of the bomb explosion.(7) Based on the explosion mechanism and the stochastic characteristic of the shell, the paper advances some reasonable hypotheses and supposes that the explosion process of the shell is a Markov process, thus constitutes two explosion models of the shell: the imitation model an...
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