摘要
工程与科学计算中研究人员需要经常性地通过可视数据描述与合作者交流思想,这类数据可能类型多样、规模庞大,且存储在远程介质上。对其进行有效的可视化不能求助于传统的单机模式,而需要研究分布式的可视化软件工具。当前计算机图形硬件能力、计算机网络技术以及可视化技术飞速发展,也为分布式可视化研究提供了必要的技术保障。
针对工程与科学计算数据的大规模可视化,本文深入研究了一类分布式可视化原型系统的软件框架和核心算法。软件框架设计方面,针对协同操作的需求,重点关注分布式可视化的协同控制权管理、协同会话重建和可视化过程共享问题。核心算法方面,针对标量场,为实现大规模数据的快速可视化,实现了一类面向非结构化网格的并行元投影体绘制算法;针对矢量场,为清晰地展示特征区域的流体流动结构,实现了一类三维矢量场流动拓扑算法。
本文分析三个协同可视化模型,然后提出一个基于命令模式的分布式协阿可视化系统框架。这个框架分成两个部分。一部分是一个分布式可视化子系统,另一部分是一个称为CESC_Remote_DI协同部件。通过使用CESC_Remote_DI,实现研究人员间的协同可视化操作。针对协同可视化控制权限,本文采用主从模式,实现协同控制权的管理,并且该控制权可以在协同者之间相互传递。通过使用紧凑、智能的控制信息,协同会话的每一步操作都记录在一个文本文件中,这样可以实现远程协同会话重建。该软件框架在协同部件之间要求很小通讯的带宽;并且在协同环境下的响应速度与单机时候的响应速度几乎一样。因此所有的协同者几乎在同时能够看到高精度的、动态的3D场景。如果网络带宽允许,CESC_Remote_DI协同部件正常是和桌面视频工具一起使用,否则该协同部件和电话会议工具一起使用。
元投影体绘制算法是非结构化网格标量场绘制的典型算法。硬件加速的元投影算法存在显存和带宽的限制,这制约了它在大规模标量场可视化中的应用,因此本文选用了软件扫描的元投影体绘制算法,并通过算法的并行化提高其对大规模数据集的适用性。集成外表面提取及光栅化算法,并构造外表面图像空间坐标的A-Buffer数据结构,解决了非凸几何网格的体绘制问题。为提高并行算法的效率和可扩展性,采用静态轮转算法较好地实现了负载平衡。在网格单元扫描转换和光线段局部合成环节运用异步通讯机制,实现了较好的并行效率。
针对CFD流场可视化,本文研究一类基于关键点分类的三维矢量场流动拓扑结构抽取算法,以避免传统矢量场可视化算法(如箭头、流线或流面)画面不清晰或控制参数(如流线或流面的初始点位置)严重依赖用户经验的缺陷。引入类似FAST的关键点分类机制,本文算法可根据用户需求自动确定流场的关键点;并通过跟踪关键点附近的流线,可清晰地展示关键区域流体流动特征。针对非滑移边界问题,本文算法能通过分析流场边界的表面摩擦场的拓扑,展示绕壁面流体的流动结构。
In engineering and scientific computation, it is common for scientists to develop visual representations of ideas and data and share with each other. The types of such data may be various, the size may be huge and the store locations may be remote. Visualizing this type of data can not resort to stand-alone mode visualization system, while needing to research distributed visualization software tools. Coupled with increasing compute power and graphics capabilities, recent advancements in the computer network have offered a technical support for the development of distributed and collaborative scientific visualization tools.
This paper presents a software framework and kernel algorithms of a distributed and collaborative visualization prototype system which is developed for large scale engineering and scientific data. The design aspect of the software framework focuses on three problems: how to manage the collaborative control, how to reestablish a collaborative session and how to construct a collaborative framework of a share visualization process. In the aspect of the kernel algorithms, a parallel cell projection volume rendering algorithm for large scale unstructured scalar data and a 3D vector field flow topology extraction algorithm for vector data are developed.
In the first place, three collaborative visualization models are discussed in detail. We then present a framework for distributed and collaborative visualization. This framework contains two parts: One is a distributed visualization subsystem, and the other is a collaborative component named CESC_Remote_DI. By using CESC_Remote_DI we implement collaborative visualization operations between researchers. Collaboration control management is implemented by an adopting master-slave management method. By using compact, intelligent controlling information and recording each operation in a text file, we implement the reestablishment remote collaboration sessions. This software framework provides many advantages besides its simpleness. The bandwidth is small because only script commands are transferred between sites. The system response time is nearly the same as that of the stand-alone mode. Therefore, all remote scientists appear to be seeing the same high resolution, dynamic, and 3D scenes simultaneously. CESC_Remote_DI is normally used along with a desktop video tool if the network bandwidth permits, or along with a normal phone conference if the network bandwidth does not permit. These remote collaboration sessions can be recorded and posted onto the Web for other scientists to playback and modify.
The cell projection volume rendering method is a classic algorithm for visualizing large-scale unstructured grid data. However, it is a challenging task to run this method on graphics hardware due to the memory and bandwidth limitations. For overcoming these limitations and providing flexibility in handling various types of cells and meshes, we develop a high accuracy Parallel Software Scanned Cell Projection (PSSCP) algorithm. By constructing an A-Buffer data structure of the image space coordinate of outside faces of the volume grid, the PSSCP can handle non-convex meshes. By using the static round-robin scheme, the PSSCP can obtain a good load balance to achieve better scalability. By using an asynchronous communication strategy on the phase of scan conversion and image composition, the PSSCP obtains a good parallel efficiency.
To avoid the limitation of traditional vector field algorithms, such as a cluttered display or the inconvenience to identify controlling parameter, a 3D vector field flow topology extraction algorithm is developed based on critical point analysis for CFD (Computational Fluid Dynamics) datasets. The algorithm can automatically identify the critical points in a vector field. Curves integrated from a small distance around critical points can clearly show the fluid flow features. In many CFD computations, no-slip boundary conditions are imposed on the velocity field. On these boundaries, the velocity is zero. The algorithm analyzes this special case by examining the skin friction field and shows the corresponding fluid flow feature round the wall boundary.
引文
[1] Greenberg S., Hayne S., and Rada R. Groupware for real-time drawing: a designer's guide. McGraw Hill, 1995.
[2] Bergeron D. Visualization reference models. Proceedings of IEEE Visualization 1993, IEEE Computer Society Press, 1993.
[3] Pagendarm H. G., and Post F. H. Comparative visualization - approaches and examples. Visualization in Scientific Computing, Springer-Verlag, Wien, 1995.
[4] Zhou H., Chen M., and Webster M.F. Comparative evaluation of visualization and experimental results using image comparison metrics. Proceedings of IEEE visualization 2002, IEEE Computer Society Press, 2002.
[5] Lord H. D. Improving the application development process with modular visualization environments. Computer Graphics, 1995, 29(2):10-12.
[6] Yong M., Argiro D., and Worley J. An object oriented visual programming language toolkit. Computer Graphics, 1995, 29(2): 25-28.
[7] Abram G., Treinish L. An extended dataflow architecture for data analysis and visualization. Computer Graphics, 1995,29(2): 17-21.
[8] OpenDX website. http://www.opendx.org/.
[9] Foulser D. IRIS Explorer: A framework for investigation. Computer Graphics, 1995,29(2): 13-16.
[10] Walton J. P. R. B. NAG's IRIS Explorer. Visualization handbook. Academic Press, 2003.
[11] Shalf J., Bethel E. W. The grid and future visualization system architectures. IEEE Computer Graphics and Applications, 2003, 23(2):6-9.
[12] Applegate L. M. Technology support for cooperative work: A framework for studying introduction and assimilation in organizations. Journal Organizational Computing, 1991,1:11-39.
[13] Fuchs H. Building telepresence system: Translating science fiction ideas into reality. Computer Graphics Forum, 1997, 16(3):C189-C189.
[14] Bly S. A., Harrison S. R., and Irwin S. MediaSpaces: bringing people together in a video, audio and computing environment. Communications of the ACM. 1993. 36(1):28-47.
[15] Brodlie K.W., Duce D.A., and Gallop J.R., et al. Distributed and collaborative visualization. Computer Graphics Forum, 2004. 23(2): 223-251.
[16] Haber R. B.. McNabb D. A. Visualization idioms: A conceptual model for scientific visualization systems. Visualization in Scientific Computing. IEEE Computer Society Press,1990:74-93.
[17]Wood J.D.,Wright H.,Brodlie K.W.Collaborative visualization.Proceedings of IEEE Visualization 1997,1997:253-259.
[18]The UK e-Science website,http://www.escience-grid.org.uk/index.htm.
[19]Amira website,http://www.amiravis.com/.
[20]Wemecke J.The Inventor Mentor.Programming object-oriented graphics with open inventor,Release 2,Addison-Wesley,1994.
[21]Amira and simulation output,http://www.amiravis.com/userguide30/.
[22]AVS/Express website,http://www.avs.com/software/soft_t/avsxps.html.
[23]AVS5 website,http://help.avs.com/AVS5/.
[24]李晓梅,黄朝晖,蔡勋等.并行与分布式可视化技术及应用.国防工业出版社,2001.
[25]Duce D.A.,Gallop J.R.,and Johnson I.J.,et al.Distributed cooperative visualization - the MANICORAL approach.Eurographics UK Chapter Conference 1998,University of Leeds,1998.
[26]Johnson G.Collaborative visualization 101.Computer Graphics,1998,32(2):8-11.
[27]cAVS project website,http://www.tacc.utexas.edu/cavs/.
[28]Cactus project website,http://www.cactuscode.org/.
[29]Globus website,http://www.globus.org/.
[30]Wierse A.,Lang U.,and Rühle R.Architechtures of distributed visualization systems and their enhancements.The 4th Eurographics Workshop on Visualization in Scientific Computing,Abingdon,U.K.,1993.
[31]Vircinity company website,http://www.vircinity.com/.
[32]Ensight website,http://www.ceintl.com/
[33]Ensight Gold-Collaboration.http://www.ceintl.com/products/collab.html.
[34]IDL website,http://www.rsinc.ocm/idl/.
[35]PV-Wave website,http://www.vni.com/products/wave/.
[36]Walton J.P.R.B.Get the picture-new directions in data visualization.Animation and scientific visualization:Tools and Applications.Academic Press,1993:29-36.
[37]MATLAB website,http://www.mathworks.com/products/matlab/.
[38]Trefethen A.E.,Menon V.S.,Chang C.C.,et al.MultiMATLAB:MATLAB on multiple processors.Technical report,1996.
[39]Hollingsworth J..Liu K..and Pauca E Parallel toolbox for MATLAB.Techincal report,Wake Forest Univesity,1996.
[40]OpenDX weather applications,http://www.research.ibm.com/weather/vis-
[41]/w_vis.htm.
[42]SOAP details,http://www.w3.org/TR/SOAP/.
[43]Visual3 website.Http://raphael.mit.edh/visual3/visual3.html.
[44] Parker S. G., Johnson C. R. SCIRun: A scientific programming environment for computational steering. Proceedings of Supercomputer 1995, Springer-Verlag, New York, 1995.
[45] Johnson C. R., Parker S., Weinstein D., et al. Component-based problem solving environments for large-scale scientific computing. Journal on Concurrency and Computation: Practice and Experience, 2002, 32(2): 1337-1349.
[46] Germain D. de St., McCorquodale J., Parker S., et al. Uintah: A massively parallel problem solving environment. The Ninth IEEE International Symposium on High Performance and Distributed Computing, 2000.
[47] Hibbard W., Dyer C. R., and Paul B. E. Display of scientific data structures for algorithm visualization. Proceedings of Visualization 1992, IEEE Computer Society Press, 1992:139-146.
[48] VisAD website. http://www.ssec.wisc.edn/-billh/visad.html.
[49] VisAD collaborations. http://www.ssec.wisc.edu/-dglo/visad-collab/.
[50] VisAD events. http://www.ssec.wisc.edu/-dglo/visad-events/.
[51 ] VTK website. //public.kitware.com/VTK/.
[52] Schroeder W. J., Martin K. M, and Lorensen W. E. The visualization toolkit: An object oriented approach to 3D graphics. Kitware, Inc., 3rd edition, 2003.
[53] VTK and CAVEs. http://www.evl.uic.edu/cavern/cavernpapers/viz98/.
[54] VTK - multi-pipe rendering. http://brighton.ncsa.uiuc.edn/-prajlich/vtk-
[55] ActorToPF/.
[56] RealVNC website. http://www.realvnc.com.
[57] TightVNC website. http://www.tightvnc.com.
[58] Brodlie K. W., Wood J. D., Boyd D. R. S. et al. Collaborative visualization using access grid. http://www.comp.leeds.ac.uk/kwb/allhands/BOF.pdf, 2002.
[59] Stegmaier S., Magallon M., and Ertl T. A generic solution for hardware-accelerated remote visualization. Joint EUROGRAPHICS-IEEE TCVG Symposium on Visualization 2002, 2002:87-94.
[60] MSN Messenger website. http://messenger.microsoft.com.
[61 ] Vizserver website. http://www.sgi.com/software/vizserver/.
[62] Using vizserver for remote medical visualization. http://
[63] www.sgi.com/features/2002/sep/manchester/.
[64] John N. W. High performance visualization in a hospital operating theatre. In Theory and Practice of Computer Graphics(TPCG2003). IEEE Computer Society Press, 2003:170-175.
[65] McCloy R. F., and John N. W. Remote visualization of patient data in the operating theatre during helpatopancreatic surgery. In Computer Assisted Radiology and Surgery(CARS2003),London,UK,2003.
[66]Humphreys G.,Houston M.,Ng R.,et al.Chromium:A stream processing framework for interactive rendering on clusters.Proceedings of SIGGRAPH 2002,ACM Press,2002:693-702.
[67]Chromium source.http://sourceforge.net/projects/chromium/.
[68]JXTA website.http://www.jxta.org/.
[69]VistaPortal website.http://www.vistaportal.com.
[70]Taylor I.,Shields M.,and Philp R.GridOneD:Peer to peer visualization using Triana:A galaxy formation test case.Proceedings of UK e-Science all hands meeting 2002,2002.
[71]WSO website.http://www.webservices.org/.
[72]Tomcat website.http://jakarta.apache.org/tomcat/index.html.
[73]WebSphere website.http://www-3.ibm.com/software/
[74]infol/websphere/index.jsp.
[75]NET website.http://www.microsoft.com/net/.
[76]gSoap website.http://www.cs.fsu.edu/engelen/soap.html.
[77]Global Grid Forum website.http://www.gridforum.org/.
[78]climateprediction.net website.http://climateprediction.net/.
[79]Stainforth D.A.,Frame D.,and Walton J.P.R.B.Visualization for public-resource climate modeling research.2003.
[80]Pang A.,Witternbrink C.K.and Goodman T.CSpray:A collaborative scientific visualization application.Proceedings of Multimedia Computing and Networking,1995.
[81]Pang A.and Smith K.Spray rendering:visualization using smart particles.Proceedings of IEEE Visualization 1993.IEEE Computer Society press,1993:302-309.
[82]Saxon E.,Wood Z.,O'Neil M.,et al.Integrated visualization of real-time environmental Data.Proceedings of Spring Conference on Computer Graphics.Bratislava,Slovakia,1997:135-143.
[83]FASTexpeditions website.http://www.nas.nasa.gov/software/FAST/FASTexpeditions/home.html.
[84]FAST website.http://www.nas.nasa.gov/software/FAST/.
[85]gViz project website.http://www.visualization.leeds.ac.uk/gViz/.
[86]ICENI project website.http://www.lesc.ic.ac.uk/iceni/index.html.
[87]Foster I.,Kesselman C.,and Nick J.,et al.The physiology of the grid:an open grid services architecture for distributed systems integration.Open Grid Service Infrastructure WG,Global Grid Forum,2002.
[88]Stanton J.,Newhouse S.,and Darlington J.Implementing a scientific visualization capability within a grid enabled component framework.Proceddings of 8th International Euro-Par Conference.volume 2400 of LNCS, Paderborn, Germany, 2002.
[89] RealityGrid project website. http://www.realitygrid.org.
[90] ICENI and RealityGrid. http://www.lesc.ic.ac.uk/projects/reality.html.
[91] Visual Beans website. http://www.acu.rl.ac.uk/VisualBeans/.
[92] 唐泽圣等．三维数据场可视化．清华大学出版社,1999．
[93] Blinn F. Light reflection functions for simulation of clouds and dusty surfaces. Proceedings of SIGGRAPH 1982,1982:21-29.
[94] Kajiya J. and Herzen B. Ray tracing volume densities. Proceedings of SIGGRAPH 1984, 1984: 165-174.
[95] Max N. Optical models for direct volume rendering. IEEE Transactions Visualization and Computer Graphics, 1995,1(2): 99-108.
[96] Sabella P. A rendering algorithm for visualizing 3D scalar fields. ACM SIGGRAPH Computer Graphics, 1988,22(4): 51-58.
[97] Tuy H., and Tuy L. Direct 2D display of 3D objects. IEEE Computer Graphics & Applications, 1984,4(10): 29-33.
[98] Foley J., Dam A., and Feiner S. et al. Computer Graphics: Principles and Practice. Addison-Wesley, 2nd edition, 1996.
[99] Levoy M. Display of surfaces from volume data. IEEE Computer Graphics & Applications, 1988, 8(5):29-37.
[100] Porter T., Duff T. Compositing digital images. Computer Graphics (Proceedings of. SIGGRAPH 1984), 1984: 253-259.
[101] Levoy M. Efficient ray tracing of volume data. ACM Transactions Computer Graphics, 1990,9(3):245-261.
[102] Wittenbrink C., Malzbender T., and Goss M. Opacity-weighted color interpolation for volume sampling. Symposium on Volume Visualization 1998, 1998: 135-142.
[103] Mueller K., Moller T., and Crawfis R. Splatting without the blur. Proceedings of IEEE Visualization 1999,1999: 363-371.
[104] Westover L. Footprint evaluation for volume rendering. Computer Graphics, 1990,24(4): 367-376.
[105] Westover L. Footprint evaluation for volume rendering. Proceedings of SIGGRAPH 1990, 1990: 367-376.
[106] Westover L. Interactive volume rendering. Chapel Hill Volume Visualization Workshop, 1989:9-16.
[107] Westover L. SPLATTING: A parallel feed-forward volume rendering algorithm. PhD Dissert. UNC-Chapel Hill, 1991.
[108] Machiraju R., and Yagel R. Efficient feed-forward volume rendering techniques for vector and parallel processors. Proceedings of Supercomputing 1993,1993: 699-708.
[109] Mueller K., and Yagel R. Fast perspective volume rendering with splatting by using a ray-driven approach. Proceedings of IEEE Visualization 1996, 1996:65-72.
[110] David F．Rogers．石教英,彭群生等译．计算机图形学的算法基础．北京,机械工业出版社,2002。
[111] Crawfis R., and Max N. Texture splats for 3D scalar and vector field visualization. Proceedings of IEEE Visualization 1993, 1993: 261-266.
[112] Cameron G. G., and Undrill P. E. Rendering voulumetric medical image data on a SIMD architecture computer. Proceedings of the Third Eurographics Workshop on Rendering, 1992:135-145.
[113] Lacroute P., Levoy M. Fast volume rendering using a shear-warp factorization of the viewing transformation. Computer Graphics, 1994: 451-458.
[114] Wihelms J., Gelder V. A coherent projection approach for direct volume rendering. Computer Graphics, 1991,24(5): 275-281.
[115] Hsu W. Segmented ray casting for data parallel volume rendering. Proceedings of Parallel Rendering Symposium 1993,1993: 93-98.
[116] Ma K. L. Parallel volume ray-casting for unstructured-grid data on distributed-memory architectures. Proceedings of Parallel Rendering Symposium 1995, 1995: 23-30.
[117] Ma K. L., and Crockett T. A scalable parallel cell-projection volume rendering algorithm for three-dimensional unstructured data. Proceedings of Parallel Rendering Symposium 1997,1997.
[118] Montani C., Perego R., and Scopigno R. Parallel volume visualization on a hypercube architecture. Proceedings of Volume Visualization Symposium 1992,1992:9-16.
[119] Parker S., Parker M., and Livnat Y., et al. Interactive ray tracing for volume visualization. IEEE Transactions on Visualization and Computer Graphics, 1999, 5(3): 238-250.
[120] Parker S., Shirley P., and Livnat Y., et al. Interactive ray tracing for isosurface rendering. Proceedings of IEEE Visualization 1998, 1998: 233-238.
[121] Challinger J. Scalable parallel volume raycasting for nonrectilinear computational grids. Proceedings of Parallel Rendering Symposium 1993, 1993:81-88.
[122] Nieh J.. and Levoy M. Volume rendering on scalable shared-memory MIMD architectures. Proceedings of Volume Visualization Symposium 1992, 1992: 17-24.
[ 123] Whitman S. A task adaptive parallel graphics Tenderer. Proceedings of Parallel Rendering Symposium 1993, 1993: 27-34.
[124] Corrie B., and Mackerras P. Parallel volume rendering and data coherence. Proceedings of Parallel Rendering Symposium 1993,1993: 23-26.
[125] Lacroute P. Analysis of a parallel volume rendering system based on the shear-warp factorization. IEEE Transactions of Visualization and Computer Graphics, 1996,2(3): 218-231.
[126] Amin M., Grama A., and Singh V. Fast volume rendering using an efficient scalable parallel formulation of the shear-warp algorithm. Proceedings of Parallel Rendering Symposium 1995, 1995: 7-14.
[127] Sano K., Kitajima H., and Kobayashi H., et al. Parallel processing of the shear-warp factorization with the binary-swap method on a distributed-memory multiprocessor system. Proceedings of Parallel Rendering Symposium 1997,1997.
[128] Molnar S., Cox M., and Ellsworth D., et al. A sorting classification of parallel rendering. IEEE Computer Graphics and Applications, 1994, 14(4): 23-32.
[129] Li P., Whitman S., and Mendoza R., et al. Prefix - A parallel splattting volume rendering system for distributed visualization. Proceedings of Parallel Rendering Symposium 1997,1997.
[130] Elvins T. Volume rendering on a distributed memory parallel computer. Proceedings of Parallel Rendering Symposium 1993,1993: 93-98.
[131] Huang J., Shareef N., and Crawfis R. et al. A parallel splatting algorithm with occlusion culling. The third Eurographics Workshop on Parallel Graphics and Visualization 2000, 2000.
[132] Silva C., Kaufman A., and Pavlakos C. PVR: High performance volume rendering. IEEE Computational Science and Engineering, 1996: 18-28.
[133] Spearey D., and Kennon S. Volume probes: interactive data exploration on arbitrary grids. Computer Graphics, 1990, 25(5): 5-12.
[134] Nielson M. Scattered data modeling. IEEE Computer Graphics and Applications, 1993,13(1): 60-70.
[135] Max N., Hanrahan P., and Crawfis R. Area and volume coherence for efficient visualization of 3D scalar functions. Computer Graphics, 1990,24(5): 27-33.
[136] Lorensen E., Cline H. Marching cubes: a high resolution 3D surface construction algorithm. Proceedings of SIGGRAPH 1987, 1987: 163-169.
[137] Leven J, Corso J, Kumar S., et al. Interactive visualization of unstructured grids using hierarchical 3D textures. Proceedings of Symposium on Volume Visualization and Graphics 2002,2002: 33-40.
[138] Williams P. Interactive splatting of nonrectilinear volumes. Proceedings of IEEE Visualization 1992,1992: 37-44.
[139] Wilhelms J., Gelder A. A coherent projection approach for direct volume rendering. Proceedings of SIGGRAPH 1991, 1991,25(4): 275-284.
[140] Shirley P., Tuchman A. A polygonal approximation to direct scalar volume rendering. ACM SIGGRAPH Computer Graphics, 1990,24(5): 63-70.
[141] Stein C., Becker B., and Max N. Sorting and hardware assisted rendering for volume visualization. Symposium on Volume Visualization 1994, 1994: 83-89.
[142] Rottger S., Kraus M., and Ertl T. Hardware-accelerated volume and isosurface rendering based on cell projection. Proceedings of IEEE Visualization 2000,2000: 109-116.
[143] Williams P. L. Visibility ordering meshed polyhedra. ACM Transactions on Graphics. 1992,11 (2): 103-125.
[144] Comba J., Klosowski J., Max N., and et al. Fast polyhedral cell sorting for interactive rendering of unstructured grids. Computer Graphics Forum, 1999, 18(3): 369-376.
[145] Silva C., Mitchell J., and Williams P. An exact interactive time visibility ordering algorithm for polyhedral cell complexes. Volume Visualization Symposium 1998,1998: 87-94.
[146] King D., Wittenbrink C., and Wolters H. An architecture for interactive tetrahedral volume rendering. International Workshop on Volume Rendering 2001,2001.
[147] Garrity M. Raytracing irregular volume data. Computer Graphics, 1990: 35-40.
[148] Uselton S. Volume rendering for computational fluid dynamics: initial results. Tech Report RNR-91-026, NASA Ames Research Center, 1991.
[149] Giertsen C. Volume visualization of sparse irregular meshes. IEEE Computer Graphics and Applications, 1992,12(2): 40-48.
[150] Yagel R., Reed D., Law A., and et al. Hardware assisted volume rendering of unstructured grids by incremental slicing. Volume Visualization Symposium 1996,1996:55-62.
[151] Westermann R., and Ertl T. Efficiently using graphics hardware in volume rendering applications. Proceedings of SIGGRAPH 1999,1999: 169-177.
[152] Bunyk P., Kaufman A., and Silva C. Simple, fast, and robust ray casting of irregular grids. Scientific Visualization, 1997: 30-36.
[153] Farias R., Mitchell J., and Silva C. ZSWEEP: an efficient and exact projection algorithm for unstructured volume rendering. ACM/IEEE Volume Visualization and Graphics Symposium 2000,2000: 91-99.
[154] Silva C., and Mitchell J. The lazy sweep ray casting algorithm for rendering irregular grids. IEEE Transactions on Visualization and Computer Graphics, 1997,3(2).
[155] Hong L., and Kaufman A. Accelerated ray-casting for curvilinear volumes. Proceedings of IEEE Visualization 1998, 1998: 247-253.
[156] Hong L., and Kaufman A. Fast projection based ray-casting algorithm for rendering curvilinear volumes. IEEE Transactions on Visualization and Computer Graphics, 1999, 5(4): 322-332.
[157] Helman J. L. and Hesselink L. Representation and display of vector field topology in fluid flow data sets. IEEE Computer, 1989, 22(8):27-36.
[158] Helman J. L. and Hesselink L. Visualizing vector field topology in fluid flows. IEEE Computer Graphics and Applications, 1991, 11(3):36-46.
[159] Laramee R. S., Weiskopf D., and Schneider J. et al. Investigating swirl and tumble flow with a comparison of visualization techniques. Proceedings IEEE Visualization 2004,2004: 51-58.
[160] 王康健,周迪斌,郑耀．基于纹理的高质量的曲面流场可视化[J]．计算机辅助设计与图形学学报,2008,20(1)：66-72．
[161] Wischgoll T., and Scheuermann G.Detection and visualization of closed streamlines in planar fields. IEEE Transactions on Visualization and Computer Graphics, 2001, 7(2).
[162] Wischgoll T, and Scheuermann G., and Hagen H. Tracking closed streamlines in time dependent planar flows. Proceedings of the Vision Modeling and Visualization Conference 2001,2001: 447-454.
[163] Theisel H., Weinkauf T, and Seidel H. P. et al. Grid independent detection of closed stream lines in 2D vector fields. Proceedings of the Conference on Vision Modeling and Visualization 2004,2004: 421-428.
[164] Scheuermann G., Hagen H., and Kruger H. et al. Visualization of higher order singularities in vector fields. Proceedings of IEEE Visualization 1997, 1997: 67-74.
[165] Scheuermann G., Hagen H., and Kriiger H. et al. Visualizing nonlinear vector field topology. IEEE Transactions on Visualization and Computer Graphics, 1998, 4(2): 109-116.
[166] Theisel H. Designing 2D vector fields of arbitrary topology. Computer Graphics Forum (Eurographics 2002), 2002,21(3):595-595.
[167] Sadarjoen I. A., and Post F. H. Detection, quantification, and tracking of vortices using streamline geometry. Computers and Graphics, 2000, 24(3):333-341.
[168] Tricoche X., Scheuermann G., and Hagen H. Topology-based visualization of time-dependent 2D vector fields. Proceedings of the Joint Eurographics - IEEE TCVG Symposium on Visualization, 2001: 117-126.
[169] Theisel H., and Seidel H. P. Feature flow fields. Proceedings of the Joint Eurographics - IEEE TCVG Symposium on Visualization, 2003: 141-148.
[170] Theisel H., Weinkauf T., and Hege H. C., et al. Stream line and path line oriented topology for 2D time-dependent vector fields. Proceedings of IEEE Visualization 2004, 2004: 321-328.
[171] Theisel H., Weinkauf T, and Hege H. C., et al. Topological methods for 2D time-dependent vector fields based on stream lines and path lines. IEEE Transactions on Visualization and Computer Graphics, 2005:11(4).
[172] Theisel H., Rossi C., and Seidel H. Using feature flow fields for topological comparison of vector fields. Proceedings of the Conference on Vision Modeling and Visualization 2003, 2003: 521-528.
[173] Heckel B., Weber G. H., and Hamann B. et al. Construction of vector field hierarchies. Proceedings of IEEE Visualization 1999, 1999: 19-26.
[174] Telea A., and van Wijk J. J. Simplified representation of vector fields. Proceedings of IEEE Visualization 1999,1999: 35-42.
[175] Lavin Y., Kumar B. R., and Hesselink L. Feature comparisons of vector fields using earth mover's distance. Proceedings of IEEE Visualization 1998, 1998:103-110.
[176] Rubner Y., Tomasi C., and Guibas L. J. A metric for distributions with applications to image databases. 1998.
[177] Kenwright D. N. Automatic detection of open and closed separation and attachment lines. Proceedings of IEEE Visualization 1998,1998: 151-158.
[178] Helman J. L. and Hesselink L. Surface representations of two and three dimensional fluid flow topology. Proceedings of IEEE Visualization 1990, 1990:6-13.
[179] Kenwright D. N., Henze C., and Levit C. Features extraction of separation and attachment lines. IEEE Transactions on Visualization and Computer Graphics, 1999, 5(2): 135-144.
[180] Tricoche X., Garth C., and Scheuermann G.Fast and robust extraction of separation line features. Proceedings of Seminar on Scientific Visualization 2003, Schloss Dagstuhl, 2003.
[181] Weinkauf T., Theisel H., and Hege H. C. et al. Boundary switch connectors for topological visualization of complex 3D vector fields. Proceedings of the Joint Eurographics - IEEE TCVG Symposium on Visualization, 2004: 183-192.
[182] Theisel H., Weinkauf T., Hege H.C. et al. Saddle connectors-an approach to visualizing the topological skeleton of complex 3D vector fields. Proceedings of IEEE Visualization 2003, 2003: 225-232.
[183] Sujudi D., and Haimes R. Identification of swirling flow in 3D vector fields. Technical Report AIAA Paper 95-1715, American Institute of Aeronautics and Astronautics, 1995.
[184] Haimes R., and Kenwright D. On the velocity gradient tensor and fluid feature extraction. Technical Report AIAA Paper 99-3288, American Institute of Aeronautics and Astronautics, 1999.
[185] Kenwright D. N., and Haimes R. Vortex identification-applications in aerodynamics. Proceedings of IEEE Visualization 1997, 1997: 413-416.
[186] Kenwright D. N., and Haimes R. Automatic vortex core detection. IEEE Computer Graphics and Applications, 1998,18(4):70-74.
[187] Roth M., and Peikert R. Flow visualization for turbomachinery design. Proceedings of IEEE Visualization 1996,1996: 381-384.
[188] Peikert R., and Roth M. The parallel vectors operator - a vector field visualization primitive. Proceedings of IEEE Visualization 1999, 1999: 263-270.
[189] Jeong J., and Hussain F. On the identification of a vortex. Journal of Fluid Mechanics. 1995,285:69-94.
[190] Banks D. C., and Singer B. A. Vortex tubes in turbulent flows: identification, representation, reconstruction. Proceedings of IEEE Visualization 1994, 1994:132-139.
[191] Banks D. C., and Singer B. A. A predictor-corrector technique for visualizing unsteady flow. IEEE Transactions on Visualization and Computer Graphics, 1995, 1(2): 151-163.
[192] Stegmaier S., and Ertl T. A graphics hardware-based vortex detection and visualization system. Proceedings of IEEE Visualization 2004, 2004: 195-202.
[193] Levy Y., Degani D., and Seginer A. Graphical visualization of vortical flows by means of helicity. AIAA Journal, 1990,28:1347-1352.
[194] Mahrous K., Bennett J. C., and Scheuermann G., et al. Topological segmentation in three-dimensional vector fields. IEEE Transactions on Visualization and Computer Graphics, 2004,10(2): 198-205.
[195] Mahrous K. M., Bennett J. C., and Hammann B. et al. Improving topological segmentation of three-dimensional vector fields. Proceedings of the Joint Eurographics - IEEE TCVG Symposium on Visualization, 2003: 203-212.
[196] Laramee R. S., Garth C., and Schneider J. et al. Texture-advection on stream surfaces: a novel hybrid visualization applied to CFD results. The Joint Eurographics - IEEE VGTC Symposium on Visualization, 2006, 386: 155-162.
[197] Loffelmann H., and Groller M. E. Enhancing the visualization of characteristic structures in dynamical systems. Proceedings of the 9th Eurographics Workshop on Visualization in Scientific Computing, 1998: 35-46.
[198] Wischgoll T., and Scheuermann G.Locating closed streamlines in 3D vector fields. Proceedings of the Joint Eurographics - IEEE TCVG Symposium on Visualization, 2002: 227-280.
[199] Tricoche X., Garth C., and Kindlmann G.et al. Visualization of intricate flow structures for vortex breakdown analysis. Proceedings of IEEE Visualization 2004,2004:187-194.
[200] Weinkauf T., Theisel H., and Hege H. C. et al. Topological construction and visualization of higher order 3D vector fields. Computer Graphics Forum, 2004, 23(3): 469-478.
[201 ] Mann S. and Rockwood A. Computing singularities of 3D vector fields with geometric algebra. Proceedings of IEEE Visualization 2002,2002: 283-290.
[202] Weinkauf T., Theisel H., and Hege H. C. et al. Extracting higher order critical points and topological simplification of 3D vector fields. Proceedings of IEEE Visualization 2005, 2005: 559-566.
[203] Tricoche X., Scheuermann G., and Hagen H. A topology simplification method for 2D vector fields. Proceedings of IEEE Visualization 2000,2000.
[204] Sun L., Batra R., and Shi X. et al. Topology visualization of the optical power flow through a novel c-shaped nano-aperture. Proceedings of IEEE Visualization 2004,2004: 337-344.
[205] Laramee R. S., Garth C., and Doleisch H. et al. Visual analysis and exploration of fluid flow in a cooling jacket. Proceedings IEEE Visualization 2005,2005: 623-630.
[206] Garth C., Tricoche X., and Scheuermann G.Tracking of vector field singularities in unstructured 3D time-dependent datasets. Proceedings IEEE of Visualization 2004, 2004: 329-335.
[207] Reinders F., Sadarjoen I. A., and Vrolijk B. et al. Vortex tracking and visualization in a flow past a tapered cylinder. Computer Graphics Forum, 2002,21(4): 675-682.
[208] Reinders F., Post F. H., and Spoelder H. J. W. Visualization of time-dependent data with feature tracking and event detection. The Visual Computer, 2001,17(1): 55-71.
[209] Theisel H., Shaner J., and Weinkauf T. et al. Extraction of parallel vector surfaces in 3D time-dependent fields and application to vortex core line tracking. Proceedings of IEEE Visualization 2005,2005: 631-638.
[210] Tricoche X., Wischgoll T., and Scheuermann G.et al. Topology tracking for the visualization of time-dependent two-dimensional flows. Computers & Graphics, 2002,26(2): 249-257.
[211] Kaufmann W. J., and Smarr L. L. Supercomputing and science. Scientific American Library, New York, 1993.
[212] McCormick B., DeFanti T., Brown M. Visualization in scientific computing. ACM Computer Graphics, 1987, 21(6).
[213] Grave M. PAGEIN final report. 02-1996.http://visu-www.onera.fr/pagein/.
[214] Wood J., Brodlie K. and Wright H. Visualization over the world wide web and its application to environmental data. Proceedings of IEEE Visualization 1996 Conference. ACM Press. 1996: 81-86.
[215] Brodlie K. Visualization over the world wide web. Proceedings of Scientific Visualization 1997 Conference, 1997: 23-29.
[216] Brodlie K., Lovegrove S. and Wood J. Harnessing the web for scientific visualization, computer graphics. ACM Computer Graphics, 2000, 34(1): 10-12.
[217] NCSA visBench. http://visbench.ncsa.uiuc.edu/.
[218] Heiland R. W., Baker M. P. and Tafti D. K. VisBench: a framework for remote data visualization and analysis. Proceedings ICCS, Springer-Verlag LNCS 2074, 2001:718-727.
[219] Michaels C., Bailey M. J. VizWiz: a java applet for interactive 3D scientific visualization on the web. Proceedings of the IEEE Visualization 1997 Conference, 1997.
[220] Taddei U. The VisAD tutorial. http://www.ssec.wisc.edu/-billh/tutorial/-
[221] index.html.
[222] Hibbard B. Interactively visualizing and steering computations. Proceedings of the IEEE Visualization 2000 Conference, Salt Lake City, 2000.
[223] Wylie B., Moreland K., and Fisk L. A. et al. Tetrahedral projection using vertex shaders. Proceedings of IEEE Volume Visualization and Graphics Symposium 2002, 2002: 7-12.
[224] Weiler M., Kraus M., and Ertl T. Hardware-based view-independent cell projection. Proceedings of IEEE Volume Visualization and Graphics Symposium 2002,2002: 13-22.
[225] Moreland K., and Angel E. A fast high accuracy volume renderer for unstructured data. Proceedings of IEEE Symposium on Volume Visualization and Graphics, 2004:9-16
[226] Williams P. L. Parallel volume rendering finite element data. Proceedings of Computer Graphics International 1993, Lausanne, Switzerland, 1993.
[227] Uselton S. Volume rendering on curvilinear grids for CFD.AIAA Paper 94-0322, 32nd Aerospace Sciences Meeting and Exhibit, 1994.
[228] Farias R., and Silva C. Parallelizing the ZSWEEP algorithm for distributed-shared memory architectures. International Workshop on Volume Graphics, 2001: 91-99.
[229] Farias R., Bentes C., and Coelho A. et al. Work distribution for parallel ZSweep algorithm. XVI Brazilian Symposium on Computer Graphics and Image Processing, 2003: 107-114.
[230] Chen L., Fujishiro I., and Nakajima K. Parallel performance optimization of large-scale unstructured data visualization for the earth simulator. Proceedings of the Fourth Eurographics Workshop on Parallel Graphics and Visualization, 2002: 133-140.
[231] Bentley J. L. Multidimensional binary search trees used for associative searching. Communications of the ACM, 1975,18(8): 509-517.
[232] Carpenter L. The A-buffer, an antialiased hidden surface method. Computer Graphics Proceedings of SIGGRAPH 1984,1984:103-108.
[233] Cook R., Max N., and Silva C. T. et al. Image-space visibility ordering for cell projection volume rendering of unstructured data. IEEE Transactions on Visualization and Computer Graphics, 2004,10 (6).
[234] Williams P., Max N. A volume density optical model. Computer Graphics (Proceedings of the 1992 Workshop on Volume Visualization), 1992: 61-68.
[235] Williams P. L., Max N., and Stein C. M. A high accuracy volume Tenderer for unstructured data. IEEE Transactions on Visualization and Computer Graphics, 1998,4(1).
[236] Kniss J., Premoze S., and Ikits M. et al. Gaussian transfer functions for multi-field volume visualization. Proceedings of IEEE Visualization 2003, 2003:497-504.
[237] Meipner M., Guthe S., and StraPer W. Interactive lighting models and pre-integration for volume rendering on PC graphics accelerators. Proceedings of Graphics Hardware 2002,2002: 209-218.
[238] Guthe S., Rottger S., and Schrieber A. et al. High-quality unstructured volume rendering on the PC platform. Proceedings of the SIGGRAPH/Eurographics Graphics Hardware Workshop 2002, 2002: 119-125.
[239] Rottger S., Ertl T. A two-step approach for interactive pre-integrated volume rendering of unstructured grids. Proceedings of IEEE Volume Visualization and Graphics Symposium 2002,2002: 23-28.
[240] Weiler M., Kraus M., and Merz M. et al. Hardware-based ray casting for tetrahedral meshes. Proceedings of IEEE Visualization 2003, 2003: 333-340.
[241] Jackins C. L. and Tanimoto S. L. Octrees and their use in representing three-dimensional objects. Computer Graphics and Image Processing, 1980, 14(3): 249-270.
[242] Floyd R. W., Rivest R. L. Algorithm 489: the algorithm SELECT - for finding the ith smallest of n elements [M1]. Communications of ACM, 1975, 18(3): 173.
[243] de Leeuw W. C., and van Liere R. Visualization of global flow structures using multiple levels of topology. Proceedings of Data Visualization 1999, 1999:45-52.
[244] Tricoche C., Scheuermann G., and Hagen H. Continuous topology simplification of planar vector fields. Proceedings of Visualization 2001, 2001:159-166.
[245] Press W. H., et al. Numerical Recipes in C++: The Art of Scientific Computing,Second Edition.Publishing House of Electronics Industry,China,2003.
[246]Lugt H.Vortex Flow in Nature and Technology.Wiley,1972.
[247]Robinson S.K.Coherent Motions in the Turbulent Boundary Layer.Ann.Rev.Fluid Mechanics,1991,23:601-639.
[248]Portela L.M.Identification and Characterization of Vortices in the Turbulent Boundary Layer.PhD thesis,Stanford University,1997.
[249]Sahner J.,Weinkauf T.,and Hege H.C.Galilean Invariant Extraction and Iconic representation of vortex core lines.Proceedings fo the Joint Eurographics - IEEE VGTC Symposium on Visualization 2005,2005.
[250]周迪斌,王康健,解利军等。基于矢量线强化的增强型二维流场实时绘制。中国图形图象学报,录用。
[251]Dibin Zhou,Kangjian Wang,Yao Zheng.Enhanced Unsteady Flow Visualization.IMSCCS 2007,Iowa,USA.2007:292-298.
[252]Dibin Zhou,Kangjian Wang,Lijun Xie et al.A Novel Pointcloud-based Isosurface Extraction.CADGraphics2007,Beijing,China,2007:76-81.
[253]Dibin Zhou,Kangjian Wang,Lijun Xie et al.Projecting tetrahedra with a simplified basis graph.IMSCCS 2007,Iowa,USA,2007:299-304.
[254]Dibin Zhou,Kangjian Wang,Yao Zheng.High-quality Texture-based Flow Visualization on Surfaces.CADGraphics2007,Beijing,China,2007:167-172.