( 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 ( 3 )在深入探討爆炸模型的構造和實時顯示的基礎上,提出了隱式破片、顯式破片的最新概念和兩種生成破片的方法:小面片等價法和面片集封閉法,并給出了三個實用的算法:虛擬實體的微粒化算法、小面片等價算法和面片集封閉算法,并對小面片等價法和面片集封閉法及其算法進行了比較。