CAJ | 학술논문

从实体造型、网格划分和网格显示三大主要功能模块介绍三维有限差分前处理系统的研制。采用CSG_BRep模型进行实体造型，引入快速成形中的切片分层技术，完成复杂实体模型的三维有限差分网格的自动划分，提出了一种快速剔除实体内部完全不可见网格面（线）的消隐算法，极大的提高了网格图的绘制速度。针对网格划分产生的零星空网格的问题，采用降维思想，提出了将同一条扫描线上，交点距离小于一倍网格步长的两个交点合并为一个交点，从根本上消除了零星空网格。
종실체조형、망격화분화망격현시삼대주요공능모괴개소삼유유한차분전처리계통적연제。채용CSG_BRep모형진행실체조형，인입쾌속성형중적절편분층기술，완성복잡실체모형적삼유유한차분망격적자동화분，제출료일충쾌속척제실체내부완전불가견망격면（선）적소은산법，겁대적제고료망격도적회제속도。침대망격화분산생적령성공망격적문제，채용강유사상，제출료장동일조소묘선상，교점거리소우일배망격보장적량개교점합병위일개교점，종근본상소제료령성공망격。
The development of three dimensional pre-processor system is introduced in three aspects: 3D modeling, grid generation and grid display. CSG_Brep model is chosen to construct entities. The slicing algorithm in RP technology is employed to achieve automatic grid generation for complicated solid models. An algorithm is proposed to remove the hidden surfaces/lines fast based on the topology of orthogonal hexahedral grids, and the speed of grid display is improved significantly. As facets are created using triangulation to approximate the CAD models, there will probably be some small gaps between two entities. If the center of the grid just falls into the small gap, there will be a fluent grid. If the distance of two intersections on the same scan line is less than the grid step, the two intersections are brought into a single point to eliminate the fluent grids.