机械工程学报
機械工程學報
궤계공정학보
CHINESE JOURNAL OF MECHANICAL ENGINEERING
2014年
19期
166-174
,共9页
可视化%二阶10节点四面体%等值面抽取%关系矩阵%压缩索引结构
可視化%二階10節點四麵體%等值麵抽取%關繫矩陣%壓縮索引結構
가시화%이계10절점사면체%등치면추취%관계구진%압축색인결구
visualization%second-order 10-node tetrahedron%isosurface extraction%ralationship matrix%compressed index structure
基于二阶10节点四面体网格单元可视化过程中存在的等值面拓扑、三角等值面片结果的计算、存储及传输代价问题，提出了基于压缩索引的等值面抽取方法。为真实表现网格单元内部等值面片拓扑结构并克服其二义性，分析并简化了二阶10节点四面体单元等参插值函数，提出顶点、棱边、表面间的关系矩阵，分别在网格单元棱边、表面及体内计算提取可以表现等值面几何拓扑特征的等值点，设计了关键点匹配规则；结合三类插值点间的逻辑关系制定了令拓扑准确唯一的等值面片三角化及优化策略，设计了辅助三角化、图像优化及绘制过程的可分裂式三角面片压缩索引结构，提出了针对初始面片及优化后面片存储结构的分裂策略。试验结果证明，该方法可准确描述及确定二阶四面体网格单元内部等值面片的唯一拓扑结构，基于压缩索引结构的计算及优化分裂方法简捷有效，可适应不同的精度要求，大幅降低了计算与绘制传输中产生的代价。
基于二階10節點四麵體網格單元可視化過程中存在的等值麵拓撲、三角等值麵片結果的計算、存儲及傳輸代價問題，提齣瞭基于壓縮索引的等值麵抽取方法。為真實錶現網格單元內部等值麵片拓撲結構併剋服其二義性，分析併簡化瞭二階10節點四麵體單元等參插值函數，提齣頂點、稜邊、錶麵間的關繫矩陣，分彆在網格單元稜邊、錶麵及體內計算提取可以錶現等值麵幾何拓撲特徵的等值點，設計瞭關鍵點匹配規則；結閤三類插值點間的邏輯關繫製定瞭令拓撲準確唯一的等值麵片三角化及優化策略，設計瞭輔助三角化、圖像優化及繪製過程的可分裂式三角麵片壓縮索引結構，提齣瞭針對初始麵片及優化後麵片存儲結構的分裂策略。試驗結果證明，該方法可準確描述及確定二階四麵體網格單元內部等值麵片的唯一拓撲結構，基于壓縮索引結構的計算及優化分裂方法簡捷有效，可適應不同的精度要求，大幅降低瞭計算與繪製傳輸中產生的代價。
기우이계10절점사면체망격단원가시화과정중존재적등치면탁복、삼각등치면편결과적계산、존저급전수대개문제，제출료기우압축색인적등치면추취방법。위진실표현망격단원내부등치면편탁복결구병극복기이의성，분석병간화료이계10절점사면체단원등삼삽치함수，제출정점、릉변、표면간적관계구진，분별재망격단원릉변、표면급체내계산제취가이표현등치면궤하탁복특정적등치점，설계료관건점필배규칙；결합삼류삽치점간적라집관계제정료령탁복준학유일적등치면편삼각화급우화책략，설계료보조삼각화、도상우화급회제과정적가분렬식삼각면편압축색인결구，제출료침대초시면편급우화후면편존저결구적분렬책략。시험결과증명，해방법가준학묘술급학정이계사면체망격단원내부등치면편적유일탁복결구，기우압축색인결구적계산급우화분렬방법간첩유효，가괄응불동적정도요구，대폭강저료계산여회제전수중산생적대개。
In order to solve the problem of isosurface topologies and the cost of triangular patches computing, storage and transmission during the visualization process in second-order 10-node tetrahedrons, the isosurface extraction method based on compressed index is proposed. To reflect the real topology of the isosurface and overcome the ambiguity, the method analyzes and simplifies the parameter interpolation function of second-order 10-node tetrahedron, proposes the matrixes of relationships between vertex, surface and cube, calculates accurate contour points in edge, extracts surface and mesh key points which can performance the geometric topological characteristics of isosurface in mesh grids, designs a key point matching rule;based on the logical relationship among the three types of interpolation critical point, it develops the isosurface triangulation and optimization rules which have accurate and unique topologies,and the split-style compress index structure of triangle to triangulation, image optimization and drawing. The experiments show that the method can describe the isosurface accurately and define an unique geometry topology within second-order tetrahedral mesh grid, the calculation and splitting optimization method based compressed index structure is simple and effective, it has the adaptability to different accuracy requirements, and can reduce the cost of computation, drawing and transmission dramatically.
