面向大规模重复结构CAD模型的快速截面可视化方法

Rapid Cross-Section Visualization Method for Large-Scale CAD Model with Repeated Structure

截面可视化是揭示复杂三维CAD模型内部结构的有效方法,但目前基于面片求交的截面可视化方法计算量大,难以实现大规模CAD模型的交互可视化,为此提出一种结合面片求交和3D纹理的混合截面交互可视化方法.针对由少量基本对象按规律摆列而成的规则CAD模型-重复结构CAD模型,在预处理阶段,将所有基本对象离散成高精度3D纹理;在可视化对象选取阶段,通过截面可视化裁剪算法选择可视化对象;在截面可视化阶段,通过预估每个对象在屏幕的投影情况选择可视化方法.该方法基于中国科学院核能安全技术研究所FDS团队自主研发的超级蒙卡核模拟软件系统SuperMC进行研究,并使用全堆芯模型以及铅基反应堆模型进行测试,结果表明,该方法视觉效果接近基于面片求交的方法,同时实现了交互可视化.

Cross-section visualization is an effective way to reveal interior structure of complex CAD model.The popular facet intersection based cross-section visualization method is of dense computation, it can’t offer interactive cross-section visualization for large scale CAD model. The paper presents a hybrid crosssection visualization method combining facet intersection and 3D texture for large-scale repeated-structure CAD model, which is consisted of small number of basic objects. All basic objects are converted intohigh-resolution 3D texture during pre-processing stage; select the visual object by the visual clipping algorithm;and during the stage, determine cross-section visualization method for each object by evaluating itsprojection on screen. The presented algorithm has been researched on the SuperMC/MCAM (multi-physicscoupling analysis modeling program) developed by the FDS team of Chinese academy of science. Both HM (Hoogenboom Martin) reactor core model and ADS (accelerator driven sub-critical system) reactor model have been used for testing. The result demonstrates that the presented method can achieve similar rendering quality as facet-intersection based method, and is fast enough for interaction.