摘要
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.
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.
出处
《江西理工大学学报》
CAS
2014年第1期34-38,共5页
Journal of Jiangxi University of Science and Technology
基金
国家自然科学基金(11172041)
江西省自然科学基金(20132BAB216019)
关键词
有限差分
前处理
网格划分
网格显示
finite difference
pre-processor
grid generation
grid display
